. " — "7—1‘ —"—‘ ‘ Thisistooertifgthatthe thesis entitled ”The Responsibilities of Artificial Breeding COOperatives for the Improvement of Dairy Cattle" presented by Delmar J. Young has been accepted towards fulfillment of the requirements for l. 3. degree in Animal Husbandry Ma or professor Date “EL”; 1958 -—— 7,—- -. - - .A --——~ - l . _- -—- —v- I'v—v—I - a .1 t.‘ n . a ‘n-’ J THE RESPONSIBILITIES OF ARTIFICIAL BREEDING COOPERATIVES FCR TEE momma: CF DAIRY CATTLE Thesis for Degree of M; S. flfiohigen State College Dolmr Jo Yong 19148 THE RESPCNSIBILITIES 0F ARTIFICIAL BREEDING COUPERATIVES PCB THE IMPROVEMENT OF DAIRY CATI‘IB By DELMAR J. YGJNG A THESIS Submitted to the School or Graduate Studies of Michigan State College of Agriculture end Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of ANIMAL HUSBANIEY 19148 KN \ \3 \ ('43:) Aclmcwledgements This writer is indebted to Professor Ronald R. Nelson, Associate in Animal Husbandry, fcr his advice and guidance in the planning and coupletion of this work. Sincere appreciation is expressed to Dr. J. F. Kendrick, Head of Dairy Herd Improvement Investigations. Bureau of Dairy Industry, Washington, D. C. for the summaries of Dairy Herd Improvement Association Records and the summaries of Artificial Breeding (imperatives in the United States. Appreciation is expressed to the Delaware Artificial Breeder's Cooperative, Inc., Newark, Delanrs, for use of breeding records of the cecpsrat ive. Sincere appreciation is expressed for the time and effort of all who helped with this study. 5.53:} 18:31 I. II. III. V. VI. TABLE OF CONTENTS Introduction Advantages of the Artificial Breeding Program The Bull Committee Source of Data Analysis of Records and Results Size of herds using Artificial Breeding Service Conception.Rate by Artificial Insemination Improvement of Dairy Cattle by Artificial Breeding The Proven Sire Type of Records for Proving and Analyzing Sires Age of Sire at Time of'Proving Factors that may Influence the Proof Sire Indexes methods of Analyzing Proven Sires The Cow'Family Influence of Sires on Cow Families Influence of Cow'Families on Sire Proofs Other Factors in Cow Family Analysis Diagranx Selecting Young Sires VII. Sounding and Proving Selected Young Sires VIII.Conclusions IX. References Page N (D 03% 3" 15 21 R3 30 52 as us as h9 51 57 c1 THE RESPCNSIBILITIES OF ARTIFICIAL BREEDING COOPERATIVES FOR THE IEPROIEMENT (F DAIRY CATTLE Introduction The expansion of artificial breeding sceperatives during the past ten years, throughout the UnitedStates has Opened a broad field of Opportunity for the application of the science of genetics in dairy cattle breeding. The artificial breeding cooperative program is the greatest dairy herd improvement dem- onstration yet devised for the mass improvement of dairy cattle in the United States. According to a report from the Bureau of Dairy Industry (6) summarizing the extent of this program through- out the United States, as of January 1, 19138, it is apparent that artificial breeding cOOperatives provide service in most of the concentrated dairy cattle areas. This report shows 963 artificial breeding scaperatives including 224,149} herds enrolled, which bred 1,194,168 cows in 19147 in 57 states. There were 1,7145 sires in artificial breeding services throughout the country. The number of cows bred in 19147 by artificial breeding was 120% over the num- ber of cows bred by this method of 19146. Approximately 13% of. the cows bred in 191.7 were registered. The extent of the artificial breeding program which began in the United States in 1938, and deveIOped during the war years to such an extent throughout the nation that the above figures are possible, proved its merit as a herd improvement program by the acceptance of dairymen in general. This picture of rapid deveIOpment 2 has changed the importance and concept of the artificial breeding cooperative as a whole. Originally, the artificial breeding co— operative was organised to centralize proven sires who had demon- strated their transmitting ability by definite progeny tests and were classified as superior sires. As this idea became generally publicised, and the coOperative program develOped in the United States as well as in private breeding herds, it created a tremendous scarcity of proven sires that were still available for service. As of January 1, l9h8, only 2h.5% of the sires used in artificial breed- ing cooperatives were proven. This leaves 75.5% as young sires or partially proven sires. Therefa'e, as this program continues to deve10p, it is an Opportune time for the animal geneticist, the agri- cultural cclleges, and the breed associations to lend their support to this program to aid these cocperatives in selecting the best possible sires from a genetic standpoint, and, to devise schemes whereby the proving of sires can be speeded up to meet this demand. Advantages of the Artificial Breeding Program Dairymen, who have used the artificial breeding program point out its many advantages as a permanent part of the dairy industry in the community. Some advantages are mentioned below: I. It provides the opportunity to use superior sires. 2. It reduces the cost of producing milk by eliminating the expense of purchasing and keeping a herd sire. 5. It provided a means of breeding cattle and eliminated losses by 5 diseases, such as Bang's disease, trichomoniasis, and granular vaginitis, all of which could be transmitted by natural service. 14. It reduced the number of offspring of arm one sire in the herd, which, if he proved of no value, would only represent a small loss and would be less likely to influence the efficiency of herd pr Odu Oti one 5. It eliminated the necessity for employees on may dairy farm to handle aged bulls. This reduced the liability of the herd owner. 6. It appealed to purebred breeders who are supporting the program for several reasons 3 to b. d. If a sire is selected from a breeder herd, it is a means of advertising. It offers a means of additional sampling of sires beyond what a breeder could afford to do himself. Example: The red factor in Holsteins. They are interested in the service as a whole because they my lease an old sire to a coOperative, and, at the same time, have this sire available to breed to old foundation females. They have access to outstanding sires used by the cooperative to supplement their own breeding program. In smaller breeding herds, it means service is available immediate- ly in case the present herd sire should go sterile before plans are made fora successor to him. 7. In case of commercial dairymen who have two breeds of cattle, they can naintain the purity of the minor breed and keep only herd sires 14 of their under breed. Example: The Holstein breeder with a few Guernsey or Jersey cows can breed them artificially. The fact that artificial insemination on a cooperative plan does fit into our scleme of dairy production, and, the fact that dairymen have accepted this movement, creates a responsibility on the part of the management of the artificial breeding oocperatives to constantly use methods of selecting sires to bring about improvement in dairy cattle. The responsibility of the coopu'ative as far as sire selection is concerned, will depend on the action of the bull selection committees. Therefore, the bull committees should be carefully selected and ther- oughly trained in the principles of genetics, and the breeding of dairy cattle, in order that they my wisely choose and develop sires for this service. The Bull Committee is The hull committees are usually appointed by the presidents of the cooperatives. The size of this ecmflttee is not limited, nor need they all be members of the cooperative. A good, well-rounded bull committee should include the following: 1. A director of the oocperative from each self-supporting Operat- ing unit to represent a single breed. 2. A representative of the state breed association for each breed in service. 5. The manager of the cooperative. 1;. A representative of tie state agricultural college, ex-officic. 5 The hull committees of most artificial breeding cooperatives today are made up as outlined above. As a specific ennple, to quote from the by-laws of The Maryland Artificial Breeders Cooperative, Inc., under Article V, Section 6, entitled "Selection of Sires", quote - “a. The Board of Directors shall name a committee of at least five members for each breed of dairy cattle serviced by the cooperative to select the bulls of a particular breed to be acquired through purchase or lease for the purpose of providing semen. (he of the members of each breed ccnmittee shall be the director-at-large for that breed and he shall be the chairman of the committee, but no other member of any such comittee is required to be a member of the Board of Directors. hbmbers of these committees shall be re- imbursed for actual expense in the performance of their duties." The breed committee chairmen of the Maryland cooperative are presidents of their respective state breed associations. This ties together the breed interests of dairy cattle in the state. Since the artificial breedixg program is on a ccmunity cr state-ride basis, it is absolutely essential that all interests work together and me the latest an! soundest concepts of dairy cattle breeding in the selection of sires for this program. At the present time, with this concerted action, there are problem that present them- selves such as various plans of animal breeding,availability of outstazrling proven sires, and sources of outstanding. young sires, which will be analysed in the thesis. The Board of Directors and bull committees of these breeding 6 oocperatives must accept the responsibilities of sire selection with an open mind and be constantly alert to the application of the fundamental principles of genetics. It must be realized that a large percentage of the men on these committees will not have scientific training in animal breeding. Their training may be limit- ed to what diey have actually observed in their on breeding program or by association with other breeders. Therefore, these men must be trained through short courses and training schools held regularly in order that they may understand the scientific approach to this problem in the selection of sires. Since: these men may not have had adequate training, a definite, simple plan of analysis must be out- lined which still be easy to understand, and, whereby they can in- terpret the probable genetic mine up of individual animals. The purpose of this thesis shall be to outline the steps in interpreting the mill: production records of the daughters of sires as a measure of the transmitting ability of a sire, and a cow family. 7 SOURCE OF DATA The data used in this thesis has_been collected frun the breed- ing records of the Delaware Artificial Breeders' Cooperative, Inc., and the production records repcrted in the Dairy Herd Improvement Association program which nuke up the breeding demonstration project of the Dairy Extension Program of the Delaware Agricultural Extension Service, University of Delaware, Newark, Delaware. This study begain in October, 19145, in order to assemble the best infomation for a long-time program of the oocperative breeding demonstration in Delaware. The problems included in this stuw are; the size of herds in the area; the breeding efficiency thd: should be expected; the improvement of dairy cattle by artificial insemina- tion; the availability and analysis of proven sires ; the methods of analysing cow families; the methods of selecting young sires 3 the methods for sampling and proving these young sires. The Delaware Artificial Breeders' C00perative, Inc. , was organ- ised April 214, 1947. The New Castle County unit of the State Co- operative operated as a county association from January l, 1912 until the organisation of the state oocperative. The New Castle County unit had 266 active members in 19147 and bred 1,972 cows during the year of 19137. . Dairy Herd Improvement Association records were collected from three breeding herds in the State of Delaware. These records were analysed to obtain information on the transmitting ability of sires and on families in these herds. (lily one of these herds was selected for analysis and discussion in this thesis. a gamma cs Rncomas mm RESUIII'S Size of Herds Using Artificial Breeding Service The question is often raised as to whether artificial breed- ing is designed for small herds for the most part, and, if the program is based entirely on dairymen who own ten cows or less. A stuw was nude in regard to this question on the records of the New Castle County unit of the Delaware Artificial Breeders COOperative, Ino., Newark, Delaware, for the year 19147, in order to compare the size of herds breeding artificially to the normal distribution of size of herds as given in the latest 11. 8. Census Report (19) in 15140. The comparison in size of herds is shown in Table l. 9__ Table l COLfl’ARISUN OF SIZE OF BIRDS USING ARTIFICIAL BREEDING TO SIZE OF EDS IN TIE COURT! OF NEW CASTLE, DELAWARE Size of: Active Members Breeding Arti- xSunInary 1939-110 U.S. Census Herds : ficially, New Castle County, :New Castle County, Delaware 3 Delaware 3 a 0.0 x o x o. s .No ,3 0.0 s o s 0.0 s e o s Mem- sTotal s Cows : Total 3 Herds :TotalsCows : Total 1: bers :Berds s Bred J_ Cows : :Herds: : Cows 0-1. m 53% 260 13% i 368 55% 815 7% 5-9 147 17% 329 17% : 170 16% 1199 11% 10-12. 31. 127: 397 20% i 221. 21% 2614.0 21% 15-19 20 8% 31g 17% I 165 15% 2728 214% 20-29 19 as Leo 23% i 103 10% 2358 21s 30 1 1 W0? 5 a 192 10% z 3% 11435 13% g... 8 w U1 U1 TOTAL 26:6 100% 1972 100% 100% 11075 100% The above table shows that 70% of the active members in the New Castle County Artificial Breeding unit, bred less than 10 can per member during the year. This includes new members, who started during the year and have not had the opportunity to breed nany cows. A high percentage of the one and two cow owners responded quickly to this service because of its convenience. However, only 30% of the total cows bred during the year were in herds of 10 cows or less. Seventy percent of the cows bred were in larger herds. The distri- bution of larger size herds corresponds very closely to the normal distribution of herds in the census report. 10 If the breeding results by artificial insemination are equal to natural service, there is automatically an approximate increase of 50% in the number of cows bred the follcwing year in the circuit. This is mostly due to an increase in the number of cows bred per herd, rather than an increase in the number of herds. This is pointed out in a national summary of the artificial breeding program reported from the Bureau of Dairy Industry (6). There were 60% more herds enrolled in 191;? over 19146, as compared to 120% increase in the number of cows bred in 19h7 over lghb. Thus the trend is for larger herds to be making no use of the artificial breeding program as it matures and becomes successful in an area. Therefore, as this program reaches its normal position in any state, there will be a gradual increase in the size of herds using the service. Concgpticn Rate by Artificial Insemination The conception rate is one of the most important factors can-- .tributing to the success of artificial insemination. A study was made at the U. 8. Bureau of Dairy Industry, Beltsville, Md., (9) on the influence of the ages of cows and bulls and the influence of the season of the year on the variation in conception rate. This study indicated that bulls had a gradual lessening of breeding efficiency with advancing age, with the exception of the 7 year old group where an unexplained decrease in services per conception were found. Young bulls were considerably more efficient when bred to virgin heifers than were bulls that were 5 years of age and over. Virgin heifers ‘required more services per conception than older cows, ll but, after the first gestation, age had little effect upon the breeding efficiency of tin cows. It was noticeable that the breed- ing efficiency was lower during the late summer than during the rest of the year. Similar studies made in Nebraska (11;) and Kentucky (10) conformed to this study at Beltsville. Another study was made in Nebraska (8) comparing the breeding efficiency of artificial insemination and natural services. This study on natural service concerning the number of services per conception has been generally used as a standard onwhich the breeding efficiency by artificial insemination may be checlmd. In this study, reports of several stations were combined to determine the average percentage of conception in a mass gro up of cattle. This study on natural service was based on calvings or pregnancy examinations of 22,681.; cows. It was found that concepticn secured by services as follows: ll‘b Service - 60.1% 14th Service - 3e% 2nd Service - 18.6% 5 or more services - 3.7% 5rd Service - 7.9% Cows became sterile - 6.5% In artificial breeding of dairy cattle, it is not practical yet for the general use of pregnancy examinations to determine the breed- ing efficiency by artificial insemination. Therefore, oocperatives use the old custun that if a cow does not can back for a repeat ser- vice, she apparently has conceived. This is called a “non return". Most studies are mede on first and second services only. Services beyond the third service become inaccurate because a cow may be bred to a bull by natural service, or sold as a non-breeder. 12 Artificial cooperatives use the term "non-return" rather than "conception” since pregnancy examinations are not given. All herds are not equal as far as the breeding efficiency is concerned. Disease conditions, general herd health and management, are the min factors to cause this variation. A study was made on the breeding results by herds in the New Castle County unit of the Delaware Artificial Breeders Cooperative, Inc., on 1,972 cars bred in 266 different herds in 19147, to determine the variations of breeding results in different herds. This study was based on the non-returns of first and second services only. The herds were grouped into 14 classes; very good; good; fair; or poor. This study included all repeat services made during the year of 19147 and the repeat services for the first 145 days in 19148. The “very good" class included herds that had 65% non-returns on first and eecondiservices. The "good“ group included herds that had 50% to 614% non-returns. The "fair” group included hard. that had be- tween 55% and 149% non-returns. The "poor" group included those herds with less than 314% non-returns. Each herd was sunmarized and classified according to Table II. lac Table II CLASSIFICATION OF BREEDING RESULTS 111 amps Classification No.0f No.cf Av.No. % of 75 of Herds Cows First Total Total Services Horde Cows 1' 65% or ma'e non-returns 1145 890 6 55 1.15 lst and 2nd services 50%-61.;% non-returns 77 751 9 29 57 1st and 2nd services 557p149% non-rettrns 16 227 114 .6 12 let an! 2nd services 511% and below, ncn- 26 1214 5 10 6 returns, lst and 2nd services This summary shows that 55% of the total active members (herds) had "very good“ results, 29% had "good" results, 6% had "fair“ results, and 10% had "pocr"results. This sash-yer”. by summarizing the breeding efficiency of the total number cf'cows bred that 145% of the cows were in the ”very good" group, 57% of the cows were in the "good“ grouP. 12% cf the cows were in the “fair” group, and 6% of the cows were in the 'poor" group. It‘is assumed that a similar variation in breeding efficiency by natural service would exist in these same herds. However, the breed- ing records in many herds are not couplete, and, therefore it is inr- probable that a futher study could be made. After this data was compiled, it was decided to compare the re- sults of each group on % of non-returns on lst service; % of non- returns on 2nd service; and the combined percentage of non-returns 114 on 1st and 2nd services with that of natural service. Table III shows this cornpar ism. Table III : Group ; % Non Returns % Non Returns % Non Returns : lst Service 2nd Service lst and 2nd 3 Services Natural Service. 1 60% 148% 56% 65% or more 11.11.!" "VG" : 77% 81% 78% 5074-65% NoR. - 'G" : 56% 58% 56% : 357wh9% 11.3. - "F" : 111% W W 311% and below 11.11. "P“ i 31% 21% 27% I Calculated from percentages given in Nebraska Study (8) es N.R. represents "Non Returns" Thelfirst two groups showed results equal to or better than that expected by natural service on the average. The two last groups, however, were mach poorer than natural service. It is noted then, that 814% of the herds and 82% of the cows had as“ good a breeding efficiency as the average by natural service. These breeding efficiency studies lave emphasized the problem of fertility in a good many dairy herds. They have created consid- erable interest among dairymen on improving the herd health, taking cooperative action in state disease control programs, and, has stim- ulated better management of the herds. Conception rates influence the number of offspring from a sire since the fertility level of a herd will determine the number of offspring that will be obtained in that herd. In new artificial breeding cooperatives, where the 15 breeding efficiency problem has been of much concern, they have resorted to the use of young unproven sires as a means to im- prove their conception rates. A part of the decrease in numbers of proven sires in service today has been caused by the breeding efficiency problem. However, as new artificial insemination techniques are developed and improvement is made in the general herd health, it will be possible to make better use of our proven sires. Improvement offlDailCattle by Artificial Breeding The results of herd improvement by artificial breeding can not as yet be neasnred as to its effect on the improvement of total herd averages. The only information available is a comparison of the daughters' records resulting from artificial insemination com- pared with the records of their respective dam. The first 120 "artificial" cows completing records in New Jersey (2) produced‘9.3% more an]: and 115‘ more butterfat than was produced by their dams during the corresponding period. A study of the re-proving cf sires by artificial insemination was made by Albrectsen (l) in New York. This stucbr included 7 proved Holstein sires used by the New York Artificial Breeders Cooperative. Each sire had 11.; or more dam and daughter comparisons. The following is a summary of the seven sires. 16 The Seven Sires by Natural Service (2 :50; d9; 11.3.2 183 daughters average 12,800 lbs. milk 5.5% 1451 lb. fat 183 dams average 11,610 lbs. mill: 5.5% 1108 lb. fat DIFFERENCE plus 1,190 lbs. milk plus h3 lb. fat The no. daughters that equaled or exceeded their dams 126 110 150 The Seven Sires by Artificial fiervice 183 daughters average 12,011 lbs. milk 3.6% 1429 lb. fat 183 dams average 11,991 lbs. mill: j.§% 1.24 lb. fat DIFFERENCE plus so lbs. milk . 1% .7 lb. m: The no. daughters that equaled or exceeded their dam e 98 109 % The 183 daughters records by artificial insemination were report- ed from ?6 different herds which introduced a more variable environp ment and a variable influence of sires previously used in these herds. The 183 dams bred artificially to these sire - - 11h had pro- duction records over 1400 lb. fat: 29 dams had over 500 lb. fat; and 5 had over 600 1b. fat. Of the 183 artificial progeny, 12h had records over boo lb. fat; 31 over 500 lb. fat; 9 over 600 lb. fat; and 1 over 700 lb. fat. 17 Albrectsen further reports that on the over-all perfornence of all sires used in the cooperative it was found as follows: Cows producing 215 lbs. fat - increase of 79 lbs. fat was obtained Cows producing 333 lbs. fat increase of bl lbs. fat was obtained Cows producing 376 lbs. fat increase of U4 lbs. fat was obtained Cows producing 1420 lbs. fat Daughters produced slightly less than dams. Cows producing 505 lbs. fat Daughters averaged L573 lbs. fat Albrectsen also reports that the average cow in New York pro- duces Q0 lbs. fat per year. Those cows on D.H.I.A. test averaged 3145 lbs. fat per year; and, all of the sires' daughters resulting from artificial insemination averaged I415 lbs. fat. A summary of D.H.I.A. proved sires in artificial breeding associations as of Januaryl, 191:7, tabulated by the Bureau of Dairy Industry (unpublished but sent to agricultural colleges throughout the 0.8.) shows that on the whole, the daughters of these proven sires exceeded their dams by 1480 lbs. milk and 27 lbs. fat. Complete information on all proved sires in artificial breeding service as of January 1, 19147, are grouped according to the butterfat range of the dams of the sires, in Table No. IV (U.S.D..L. Bureau of Dairy Industry Sumary, September 19, 19147.) l8 Table IV Butterfat production SIRES THAT Aver‘ge Production Dif- range of Sires W fer- dm °r m' pm' m m an" jpcunds) rod. a a Fat Yer—213. to. m. n... m. Tbs. n... 250*27h 1 1 0 - 5.5h1 363 6.5h0 5H5 9 75 275-299 6 6 0 7.19h 291 3.h95 55h * b5 500-32h 11 10 1 7.129 51“ 7.990 561 0 h? 325'5149 21 17 Li 8,221 538 9s059 582 ’ Mt 350-5Th 63 51 12 3.995 563 9.887 h05 *«hz 575-599 60 59 21 9.h85 389 9.9b2 h19 O 30 boo-1.2. 67 157 20 10,509 1411 10,981 1438 e 27 h25-bh9 ha 27 21 10.713 b56 10.717 Q39 9 5 1:50-1:71! Z7 21 b 12.117 1559 12 .1455 1535 ‘3 21-: 1.75-1.99 20 12 8 12.h16 1.86 12.516 1:91 o 5 500-52h 9 7 2 13.80h 508 1h.1h3 516 9 3 550:5714 2 0 2 11-14176 555 124863 1486 - 69 Total 335 238 97 Av. 10,099 to; 10,580 1430 .27 There were 97 sires in the above table that decreased production, and 238 sires that maintained or increased production. The table shows that only 71% of the 335 .1... in artificial breeding service as of January 1, 191.7 nintained or increased production, while 29% of the sires were unable to maintain the production level of the dams with which they were mated. However, the group of sires as a whole in- creased their daughters' producti on over their dams' production. It is evident that when sires are sated to dams whose production average is below 300 lbs. butterfat, there is a greater increase in the butter- fat production of the daughters over their dams. There was little difference in the amount of increase in production records of sires bred to groups of dams between 3U0 lbs. of butterfat and 1425 lbs. butterfat. 9 When sires were mated to dams that averaged over 125 lbs. butterfat, it became more difficult to show any improvement. It is evident that only a smll percentage of sires canmaintain a level of production over 1425 lbs. butterfat. There is evidence that it is difficult to find sira, who when mated to dams producing over 500 lbs. butterfat, are able to maintain or cause any increase in production in their daughters. A study was made in Delaware in preparation for this thesis to determine the improvement in production that had resulted from the opera.- tion of the New Castle County Artificial Breeding Cooperative (19142- 19117) in New Castle County, Delaware. The D.H.I.A. records as reported by the D.B.I.A. supervisors were tabulated at the Bureau of Dairy Indus- try in Washington to officially prove the first six sires used in the artificial breeding service. A sunmary of these proofs is shown in Table Vs Table V Summary of the First Six Sires Used in the Delaware Artificial Breeding Program AVERAGE H? ODUC T ION No. of No. of Dams Daughters Differences Sires Breed Pairs HIE B-I'at' BITE “at" HIE H'at No. Lbs . “Lbj. Lbs . ‘ Lbs. Lbs . Lbs L4 0e l Guernsey 11; 7,258 3141; 8,1;22 1418 01,161.; e 714 3 Holstein 35 11,825 1.86 12,972 1.86 “.11.? . co 2 g Jersey_ 2}; 8,993 399 8,886 141.17 e 792 9148 e AllBreeds 73 9,722 1401 10,756 1.61 .1,o3h . so I I 20 Table No. 5 shows that the 6 sires (including all breeds) had daughters that produced lr% more milk and 15%imore butterfat than their dams. Another point not shown in the table is that cut of 73 pairs, b5 daughters (62%) exceeded their dams in.milk:prcducticn; 51 daughters (70%) exceeded their dams in butterfat tests; 53 daughe ters (73%) exceeded their dams in total butterfat production. This study of the improvement of dairy cattle in New Castle County, Delaware (though it is small) shows that sires are being bred to cows that average h00 lbs. of butterfat, while the average pro- duction of cows cn.D.H.I.A. test is 325 lb. of butterfat. The aver- age prcduction.per cow in Delaware, according to the U.S. Census Report is l80 lbs. of butterfat per year. These results show that the artificial breeding program is in- proving the dairy cattle pcpulation. However, the records used were obtained from herds on test in which milk production was on a higher level than the average cow in the area. There is need of better feed and management practices among small dairymen and herds not on test in order that a full expression of these transmitted dairy characters will result in more efficient milk production. Since more herds on test are using the artificial breeding pro- gram, it increases the responsibility of the bull committee of an artificial breeding cooperative in.the selection of sires that will maintain or show improvement in the higher producing herds. This becomes a challenge tc»the bull committees to use the best available methods of analyzing sires and cow families to assure results in those herds already of a high producing level. 21 The Proven Sire Various tern- have been used by breed associations for sires that have not specific standards of performance. These terms have been used in breed advertising, sales promotion, pedigrees, and dairy magazines, until breeders and dairymen have associated aw term given to sires as one waning a specific standard of merit. Thus when the term "proven" sires came into use through the sire- proving program of D.H.I.A., breeders and dairymen think of the ”proven sire" as a sire of superior merit. It is disturbing to some dairymen to learn that the term "proven sire“ could be a sire having daughters of low producing ability. This tern at the present time is used in some breed advertisements meaning an A.R. sire or gold medal sire or any sire attaining the rank of superior sire within a breed. The bull committees of artificial breeding cooperatives must understand the term "proven sire". They should males every effort to inform their members ”what the true meaning of the term “proven sire“ really is. The term ”proven sire“ in D.H.I.A. is applied to a sire. when the production records of 5 or more of his unselected daughters luvs been compared with their respective dams on a uniform basis. This does not mean that the sire is valuable. The proved sire may . transmit a high, medium or low producing capacity to his daughters. We could define a "proved sire” in this way: . 'A proved sire is a sire on which we have sufficient infcmation on his unselected daughters to determine his transmitting ability. The greater the amount of information, the more accurate is his proof.” 22 This definition does not specify any particular standard. It introduces a concept of applied genetics in studying the per- formance of sires. It offers no conclusions as to the transmitting ability of a sire but encourages continuous study of the individual by additional information accumulated as more daughters complete records. 'As these daughters grow into maturity, continuous observa- tion of their offspring strengthens the evidence of transmitting ability of the sire as expressed by his proven sons and performance of his granddaughters. Type of Records for Proving and Analyzing Sires Dairy Herd Improvement Association or hard improvement registry records of the breed associations are the best records on which to base a breeding program or breeding analysis. It is recommended that herds first join a D.H.I.A. unit in order to measure the results of feeding and managemt. Then, when the herd averages approach 350 lbs. of butterfat per year, the'H.I.R. testing plan should be combined with D.H.I.A. in registered herds. Grade herds should continue on D.H.I.A. Both of these testing programs require that all animals that freshen in the herd be identified and recorded in the herd record. Thus, information is obtained on the unselected daughters of a sire as these daughters freshen. If animals are sold because of inferior merit, the record will show this fact. A D.H.I.A. and/or H.I.R. canbinaticn testing program is the most complete testing program 23 available today to which a breeder nay submit his herd. This testing program includes all animals in the herd and determines the herd average whereby the daughters of a sire can be compared with contemporary cows in the herd. - Advanced Registry or LR. testing is an evasive or simple kind of herd testing. Selected animals are tested which permits only records of the best daughters of a sire to be tested and advertised. The effi- cient performnce of the herd as a whole is not recorded, and, thus not known. D.H.I.A. records furnish valuable infamtion fordairymen and bull comittees of artificial breeding coopa'atives on which to base their analysis in selecting sires. D.H.I.A. records aid in selecting sires in these ways: i. Furnishing records of feed consumed and feed cost of producing mill: which will reflect changes of food cost, feeding levels and mill: price. 2. Furnish identification of offspring. 5. Furnish evidence to neasure not only the improvement of milk production per cow, but, furnish evidence as to the effects of breeding for more efficient milk production. 14. Furnish records on greater numbers of offspring of sires for a better analysis of transmitting ability. A close relation must exist between the artificial breeding program ani the testing program. Both are dependent on each other, Artificial breeding cooperatives must stimulate D.H.I.A. testing in herds that are 1.5 cats or more in size. It should promote owner- 2h sampler testing or sort other testing program for herds under 15 cows. Testing facilities can be furnished through their local laboratories in Operating circuits, in order that more records my be available to study the effects of the artificial breeding pro- gram and to obtain more information on thetransmitting ability of sires. Official type classification must be encouraged by artificial breeding oocperatives in order to get official type rating of founda- tion breeding stock. Type committees within artificial breeding oocperatives may be trained and used in placing an unofficial type rating on animals that will not likely be classified officially. This information on type or abnormal characteristics my be recorded and used in proved sire and cow family analysis. fie of Sire at Time of Proving Breeding dairy cattle is a,slow process. Thus, the proving of sires is limited to thenatural developmmt of the dairy cow. Bulls can be used for light service (Rice 15) at me year of age with the number of services being controlled so that not more than 10 to 15 services are allowed befoze the bull is 2 years of age, with at least an interval of one week between services. It will be nine months to eighteen months before am heifer calves are dropped. Then it will tales 3 years before these heifers can complete one lactation record. Thus, the minimum age of proving a sire is 5 years of age. In most cases by natural service, sires are 6 to 8 years of age before they are proven. 25 Statements lave been mde by many writers that artificial insemination will speed up the proving of sires. Nature still has control of the breeding of dairy cattle. Therefore, the natural processes limit the fact that sires can not likely be proven under 5' years of age. It is possible to speed up the proving of sires before they are 6 or 8 years of age by artificial insemination, and, at the same time, have more dam and daughter comparisons. If a sire is in regular use by artificial breeding cooperatives his proving by 5 years of age is not likely to happen.- Haever, if planned matings are made by artificial insemination, the minimum time for proving a sire is 5 years of age. This will be discussed at greater length later in the thesis. D.H.I.A. is the major testing program and is in the lead for providing data to prove sires. There were 33,271.; herds consisting of 886,129 cows on test on January 1, 19h8, (B.D.I.) - (5). This is 3.5% of the total cow p0pulation. There are 13% of the herds of 15 cows or more in the 0.8. on test, with the possibility of mny more on test in 19149. The number of sires being proven in the 11.8. is rapidly increas-. ing to meet the demand for proven sires. However, as yet there are not sufficient living, fertile and desirably proven sires available to meet the demand of breeder cooperatives. There were 3,820 D.H.I.a. sires proved in 19147 according to the January, 1948, Bureau of Dairy Industry DeHeIeAe News Letter Volume 214, NO. 1. 26 The story as to the number of proven sires still living after having been proven, by breeds and by ages, is shown in Table VI, which is the latest sumary compiled by the Bureau of Dairy Industry (13.0.1. ) (1.) on 725 proven sires canpiled in 191.6. Table VI NUMBER OF SIRES RBPCRTED ALIVE OR DEAD, AND THE PRODUCTION OF THEIR DAUGHTERS COMPARED WITH THAT OF THEIR DADGHTERS' DALE Status Average Production of Dau hters Sires Sires W HIE Bfit‘terTat Dc. % Tbs. r Lbs. 113s. libs. ”Vine 237 33 10.2112 14.0 1109 10.897 14-1 Mob Dad 273 38 10.070 3.9 391 9.8115 3.9 388 :3: reported 215 29 9,922 5.9 587 9,338 1.9 390 a1 or Average 725 100 10,082 3.9 595 10,202 1..0 1.07 w Number of Living Sires by Age and Breed Age Brown Red gears) Ayrshire Swiss Guernsey Holstein Jeri Dam TOTAL 3 - - - 2 1 - 3 o 1 - 6 l7 6 - 30 7 5 - 15 31 10 - 61 8 1 1 9 22 L; 1 58 9 3 3 5 15 6 - 32 lo 2 1 8 21 9 - hi 11 l 2 1; 9 5 - 19 12 l - 2 3 - - 6 l5 - - 2 l 1 - 1; 11. - - - 2 - - 2 No report - - - - A 1 - 1 TOTAL 11. 7 51 123 1.1 1 237 . 27 This summary shows that approximately one third of the bulls that have been.prwen.at the present time, are still living. Of those still living, very few bulls over 10 years of age will be available for much use by artificial insemination. Besides there are sires in the lower age group that may be culled out because of low fertility, disease conditions and‘the possibility that some*wi11 not work for artificial collection. This indicates that relatively few fertile sires will be available for artificial insemination. It is observed too, that more old Helstein bulls are living than those of other breeds. This is true in the number cf‘proven.sires active in artificial breeding oocperatives. It is evident in the preceding table that at least one third of the bulls are apparently culled out because of low production. It is probable that a high percentage of those not reported,'were sold for beef before proving because breeders at the present time, are a bit anxious to let it be known that a sire is living if‘he proves with a plus index. ' Thds table clearly illustrates that bull committees of artificial breed oocperatives, breed associations and others, must take positive action in proving sires at a younger age. They must select young sires and train.then1for use in artificial service. They must protect these young sires from disease conditions, and use the best known methods of feeding and managing the young sires to extend their fertile life for more extended use as a proven sire in.artificial breeding cooperap tives. 28 Factors that may Influence the Proof The best nethod of determining the transmitting ability of a sire, is by comparing the performance of a sire's daughters with the perfornance of their respective dams. This method is known as the dam and daughter comparison proof. The sire transmits one- half of the inheritance to each of his daughters. Therefore, by comparing the variation of a sire's daughters with the variation of the daughters' dam, an indication as to his probable trans- mitting ability is expressed for observation and may be used for a partial conclusion. This observation will not, or can not result in a definite conclusion as to the actual transmitting ability of the sire. Search should continue through the offspring of the sire's daughters, and, through eons of the original parents. The offspring of the sons and daughters will give the second generation from the original parental ratings. The basis for continuing the observation is established by the fact that in a population most characters trans- mitted by the parents will appear in first and second generations. The first expression, then, of a sire's transmitting ability will appear in his daughters. By comparing one daughter with another daughter, as well as with their respective dams, the first step in genetic analysis is made. However, the expression in the daughters can be influenced by factors other than heriditary, since the methods of measuring inheritance in dairy cattle is based on the 29 combined makeup of an endocrine system, a digestive system, and a glandular system, ami, is expressed by the production of the mammary gland (udder) which is recorded as pounds of milk and pounds of butterfat. Variation, a tool of genetic science, will occur depending on the following factors that influence production records: 1. Inheritance of milk producing characters. 2. Feeding levels - kind, amount, and quality of feed fed the daughters as compared to the dams. 5. Methods of management - managed milking, regularity of feeding, arfi handling which encourages full performance and control of the endocrine system. 14. Type of matings - outcrossing or inbreeding. 5. Economic conditions - supply and demand for milk. High milk prices encourages heavier feeding than low milk prices. 6. Growth and maturity of daughters as compared to the growth and naturity of tie dams. 7. The dams 'records completed in one herd and the daughters' records completed in another. 8. Time of freshening - daughters freshening in the fall, dams freshening in the spring, or vice versa. 9. Climatic conditions - drought seasons, wet seasons, both may influence length and quality of pasture season. 10. Herd health - disease (mastitis, Bang's disease, etc.) Selection of sires of superior transmitting ability can not be based entirely on a mathematical analysis because the above condi- 50 tione can not be given a true mathematical evaluation. However, breeders must take these factors into consideration in analyzing the production records as a basis for their selection. The breed committees of artificial breeding cooperatives must have knowledge of the influ- encing factors, plus the understanding of the fundamentals of genetics, plus a keen ability for observation, plus experience to do a good job in selecting young sires from proven sires and proven cow families. 0’ Sire Indexes The term “sire index" namely, Mount Hope Index and Equal Parent Index, was rapidly accepted by breeders of dairy cattle. They used the data in their advertisements and pedigrees of their purebred ani- mals. But, in time, they found that the indexes of sires were not com- parable in different environments, and, therefore provided little in- formticn forthe selection of sires and their mates. Breeders have largely discontinued using sire indexes in their advertisements. Credit should be given to the sire index idea for stimulating interest by breeders in the transmtting ability of sires and dams which has result- ed in greater interest in dairy cattle breeding. There are nany sire index formulas proposed, such as the Mount Hope Index; the Equal Parent or Intermediate Index; the Yapp Index; Hanson Index; the Regression Index; the New Index (16), etc. They do not fill the need in selecting breeding animals. They would be accept- able provided the environmental influences were constant. Another point is that the average breeder is unable to calculate the indexes fa' his own sires, and, therefore reverts back to actual production records of pounds of milk and pounds of butterfat. 31 The best indexes that can be used by the bull committees is the direct dam and daughter comparison using the actual milk and butterfat production records corrected to a mature equivalent. Dairymen and breeders can understand these records. The pedigree is, of course, a useful tool providing it contains all information on all individuals'within two and three generations. Pedigrees furnish the only information until females come into:milk and the daughters of sires come into production. The per- formance of the progem thus expresses the trananitting ability of the parents. The pedigree shows by record the performance of individuals in the ancestry. The pedigree thenutakes second position.in an analysis. The actual dam and daughter comparison index (11.3. ) is the best expression of transmitting ability 1: used as described by Lush and Nelson (12) of Iowa. Lush states, “Transmitting ability has to be ex- pressed with reference to some standard set of environmmtal conditions. The very same transmitting ability which would causeuan average produc- tion.cf'500 lbs. of fat under one set of conditions would just as surely lead to boo lbs. fat under another less favorable set of coalitions. It is meaningless to compare transmitting abilities unless we infer that the environmental conditions were equally favorable for the groups of animls being compared.” Thus, if environmental factors are carefully considered and appraised, the study of danland daughter comparisons can be studied with a chance of good selection. Lush (15) points out an- other factcr that is of importance. He states, "From the principles governing the accuracy of dam and daughter comparisms, it is clear that accuracy is low when the number of pairs is very small but it is also clear that accuracy does not suddenlybecome perfect when a certain 32 number is reached. Instead the accuracy increases at an ever decreasing rate as the number rises.” The damxand daughter comparison.method‘will be used from this point on in this thesis. lbthods of Analysing Proven Sires (Dam and Daughter Comparisons) The first step is to establish a standard yardstick by which pros duction records are collected and summarized on individual damnamd daughter comparisons. Since milk production is on a farm unit basis, good management practices should be considered for comparisons of records. Therefore, the following factors are suggested in summarising data: 1. Two time a day milking - this conforms to the practical operas tions of dairy farms producing mdlk with efficient utilisation of labor. 2. 305 day lactation records - D.H.I.A. records show that a calving frequency of 12 to lb months will yield a higher lifetime return over feed costs. This allows 10 months production and a 2 month dry period. 3. Frequency of calving or number of records - frequency of calving records indicate the fertility of the individual. h. Mature equimalent basis - the influence of’age is reduced‘hy correcting to a mature age. Actual records of the same ages are better. However, the records of the dam as a 2 year old will not be made during the same period as the daughter's records. 5. D.E.I.L. or HQI.R. testing records obtained from practical herd operations should be used preferably to any other records. 33 The second step of analysis is made after records are collected on five or more dam and daughter comparisons using the unselected daughters' records as they complete their lactations. When only the first five dam and daughter comparisons are coanpleted the results are indicative of transmitting ability but are not conclusive. Experience has shown that if ten or more unselected dam and daughter oanparisons are completed, the results become more conclusive. The following differences have been used as a partial guide in estimating the signi- ficance of an increase or decrease in the daughters' records of a sire when compared with the records of their respective dams: 25 lb. fat on 5 dam and daughter comparisons 20 lb. fat on 10 dam and daughter comparisons 15 1b. fat on 15 dam and daughter comparisons 10 1b. fat on 20 dam and'daughter comparisons 5 1b. fat on 25 dam and daughter comparisons In addition to this plus or minus difference, consideration should be given to the average records of both the daughters and the dam in relation to the herd average or breed average. Referring to the D.H.I.A. Proved Sire Sumary of Sherwood Forest Judge (see table VII) there is a difference of 71.; 1b. of butterfat increase in the average production of 114 daughters of Judge compared with their dams. This increase is significant. It is also observed in the proof that the dams' average production was less than the breed average and the daughters' production averaged 15 1b. of butterfat over the breed average. (Breed average, Guernsey - 2 I 305 days - 14.8. - 573 lb. 5h butterfat. This is significant because this sire raised the pro- duction records of all daughters except one, over the breed average. The third step is to determine the percentage of daughters that ‘ exceed their dams in milk production, butterfat tests, and in total butterfat production. A sire of superior transmitting ability will show 60% or more of his daughters exceeding their dams in production. An average sire who is barely able to maintain production will have I about 50% of his daughters exceeding their dams in production, and, a poor transmitting sire will have only a small percentage of his daughters that equal or exceed their dams in milk production. This step is used in comparing the production records of the dams and dau- ghters to the breed average or herd average. If the average production of the dams is over 500 lbs. of butterfat, it is unlikely that more than 50% of a sire's daughters would exceed their dams. If the daughters do recede in production, it should be observed whether their average production is above the breed average level, at the breed average level, or below the breed average. Since‘it is evident that sires in artificial breeding are being rated to dams whose average pro- ducticm is between 1400-1425 lbs. butterfat, the problem is to select sires that have demonstrated their ability to maintain or improve this production. In examining the proof of Sherwood Forest Judge - 273228, in the following table, we find the daughters' average is 145 lb. of butter- fat aver the breed average. Also, 57% of his daughters exceed their dam in milk producti on, and 71% of his daughters exceed their dams 55 in butterfat tests and 78% of his daughters exceed their dam in total butterfat. Thus, the application of the first three steps as outlined above on the proof of Judge indicates that he is a sire of superior transmitting ability. gm mo maBmUan ho mamoomm nuisance mmmmmgdn a: was mo mamoomm so: m3 omen m omw .33 NH Essen... .4555 swooped I seem eowmoovzvoz omm m3 3%. H mom mHHmoHoom 3m H3 .38 H can mommmm Km 5.: memo H 8m «83.8 is m: 3:. ooaoaornn 2 9m 86 m emu an an: mmfl. m Hmm shod .HH owsucbd mm: o.m Hon m Hmm wmmmom . Hmv Rm an: on: .H emu 383 em: 9: H32 x mmm mmmmt . 3V omm 9m fimo m mmm mono? Hm: H.m mmmm m Em makes . M3 in 9: meme m mam .338 .3: m3 Hmnm m mom «ES» a mw Rm sin 05. .H omm mmmmoo «mm 3 ammo m How. 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H mom masons a HHV mmm mi .32. m :mm 3030. mm: H.m mmmm , H mom mmmsmsom . m3 om: an: mmmm m Rm mmmmousom em: m.: 38H m Hon 882. a a: :3 m3 moms m mam :38? mo: m.: mon H mom emommo . 8: 2: H3 58 m mom e334 53 .23 .5 one .oz .95 .34 . .5. min .oz 394 K .b4 .oom when nomads: .bd R :5 .oo% when meager“ pom pom aHHa .oz 82.5 -353 .oz ham one son aHHa .oz 62.5 .353 manna mumps Samoa 802%.» .. $335 an magma .4455 HHP 0.368 T v \IIL 4655.12 so... 2: 2 8-58 I 3.8%.... 58 The 14th step in the analytical procedure is to prepare a range and arrow chart of the total butterfat production of each of the dam and daughter comparisons to illustrate or graphically present the data as a picture for comparative analysis. The Range Chart - Part A - (graphic illustration D.H.I.A. proof, Sherwood Forest Judge). The range chart illustrates the range in butter- fat production from the lowest producing dam to the highest producing dam. . It is noted that the lowest dam falls at 291; lbs. of butterfat, while the highest dam averaged 1.27 lb. butterfat. There is a group of dams falling between 300 and 550 lb. butterfat, and, another group appearing with over 1400 lb. butterfat. A few dams are scattered in the remaining intervals. The daughters' range graphed in the same manner shows the lowest daughter 's average production was 292 lb. butterfat, while the highest producing daughter averaged 148).; 1b. butterfat. However, the daughters records were not evenly spaced between the lowest and the highest re- cord. It is noted that 15 of the daughters' records fell between 586 1b. butterfat and llbh lb. butterfat. Thus, the variation of the daughters' expression is limited to a close range at a' level over breed average. The variation of the (hms' records is extended and the majority of the records are below breed average. Thus, the range comparison of varia- tion shows evidence of superior transmitting ability. The Arrow ChartA- Part B - The arrow chart in the previous graph presents the individual dam and daughter comparisons. The pairs are arranged according to the butterfat production of the clans starting with the lowest produoixg dam and following through to the highest 2") producing dam. The base of the arrow is the dam's average record and the point of the arrow represents the daughter's average record. Bars connecting the dams represent two full sisters or daughters out of the same dam. The numbers in parenthesis represent the number of records averaged. The analysis of these pairs shows that most of the daughters that have records better than their dams are all out of dams below the breed average with the exception of one comparison. Each arrow represents a definite mating of the sire with a cow. Therefore, in case of the lOth pair, the dam may not have the ability to transmit to her offspring the combination of inheritance that she expresses. If the dam trans- mitted low production, and, by chance this daughter received some factors of lav production from her sire, it would explain the abnormal low pro- duction of this daughter. Some of the characters inherited from the sire may have been covered up by the dam's characters which could re- sult in the abnormal production of this daughter. This daughter, who is so abnormal in production, raises a question as to what is the per- formnce of her particulm' cow family. This will be shown later. This graph illustrates another genetic principle. This principle is known as a ”breaking point” in production whereby the production records of a sire's daughters tend to drcp back from the dafl' production records. It is noted that the "breaking point" of this sire is between 1400-1420 lbs. butterfat. Even though the daughters' records tend to drop below the production records of the dams", they remain in close range of all daughters tested. . This D.H.I.A. proved sire summary of Sherwood Forest Judge was selected for this analysis because the production records of the dams I40 am the daughters were made on D.H.I.A. tests. The feeding and management of this herd would be considered good, average care. This as the first D.H.I.A. sire proven in the herd. All daughters that freshened were included in this proof, without amt idea of selection. Therefore, this proved sire was chosen as an example for this analysis. In the analysis of this sire, we found the following points that would lead us to believe that this sire has superior transmitting ability for a high level of production. These points are: l. 114 Pairs showed an increase of 714 lb. butterfat over the dams - (145 lb. butterfat over breed average ).. 2. Approximately 70% of his daughters exceeded their dams. 5. The range of daughters' production records was limited to a narrow range with dams' records extended over a wide range. I4. 13 of his daughters' production records were above breed average showing a uniform production regardless of the dams' production records. 5. The appearance of a definite breaking point between 1400-1420 lb. butterfat . This analysis indicates that we can expect this sire, Sherwood Forest 1 Judge, to be a herd improver, or classify him as a I'superior trans- mitting sire.". We can also reasonably expect from-this evidence that sons of this sire would receive similar inheritance to that his daughters received. Therefore, the bull committees should select sires by this analytical procedure for artificial breeding cooperatives and 141 plan to save sons by a sire of this caliber out of proven cow families as part of the responsibility that artificial breeding cooperatives have for the improvement-of dairy cattle. Another fundamental principle of genetics is knom as a heterozygous or mixed inheritance. Evidence of this principle would have appeared under the same environmental conditions beginning with a wide variation in the production records of the daughters, absence of a ”breaking point", and, an equal number of daughters falling above and below the breeddaverage. A son of a heterozygous (mixed) sire would be question- able fcr use as a herd sire. The bull committee of an artificial breed- ing oocperative should recognia this fact and expect to have as marv poor daughters from this type sire. A poor sire than, would show a decrease in production and his daughters' average production would be below the breed average. Most members of an artificial breeding oocperative's bull canmittee are capable of analyzing proven sires by this method with good assur- ance of repeatability in the daughters of the sire selected for arti- ficial inseminatim. When outstanding sires are selected, plans should be made for mating this sire to outstanding brood cows for the purpose of saving sons to be sampled and used later in the artificial breeding program. 142 THE cow anr Dairy Herd Improvement Association records compiled in the Bureau of Dairy Industry (la) in Washington, D. 0., for the proving of sires by dam and daughter comparisons are now being used in another phase of D.H.I.A. testing. When herds have been on D.H.I.A. tdst long enough to prove three sires in the herd, the hard data may be canpiled to show by generations the cow family lines that are represented. This is known as the "herd analysis phase" and lays particular emphasis on sires and female or cow families in the herd. These herd analysis tabulations indicate the productive efficiency and breeding worth of each cow am cow family in the herd. The hard analysis provides the dairymen with a diagram or blueprint of the breeding program that has been followed in the past and indicates which cow families should be perpetuated or discarded in order to improve the transmitting ability of the herd. Emphasis on the cow family, in addition to the sire proving phase, provides more information on the transmitting ability of both parents than the pedigree or pedigree index. The combined study of proven sires and cow families, together in a blueprint diagram (herd analysis diagram as shawl) shows the influence of sires on cow families and the influ- ence of cow families on sire proofs. The herd analysis blueprint is the practical application to some extent of a suggestim by Lush (l2) for the analysis of transmitting ability in dairy cattle. He suggests, ”That automatic methods of correcting for unknown environmental conditions such as comparing a bull's daughters with the average of the other contemporary cows in the herd, seem to deserve wider use than they have yet received.” 1:3 Figure II —‘ 250195 275228 flame of Sire 'Woodbine's Royalist Sherwood Forest Judge All Tested Daughs. Tested Pairs 7 10 lbs. % Lbs. Lbs. % Lbs. Milk Test Fat Milk Test Fat Av. of all Daughs. Av.Dau.from tested dams‘6855 h.8 329 8519 h.9 hl7 Av. of Dams 7776 h.h fihl 6967 h.7 329 Difference '92} e.h '12 16529 9.2 e88 Dau.that - or e dams 5 7 5 7 7 8 Family No. 1 706711 W 5888142 767752 ‘ 471;}? .e (.2)§¢'?,‘,g£37 14.7 530203 7723 (3) 736627“ 5.3 ”WET; 14.5 708600 WW “.5 /631(2%‘< (2) 717.? be 767739 (2) 5.1 We? ‘35! (3)739 14.6 Faily NO. II 693636 ms m9 290958 P”””"”fl,..—e,..——’4 )TEGE ___—-‘-\\\\£E%§§§REZ:: 558516 . 67522h (”mm .7 (27% the (hi—5997552 5.3 \nga 70852: (24) gg m 25% 5.9 r‘ Family No. III 708597 515537 ——-""“9m W< (2)155 (111.337 m 767758 - Wm M4 Tl'n herd analysis as sham is tabn from the same herd as the records for proving Sherwood Forest Judge. This diagram shows 3 cow families in the had. A large family, a medium sized family, and the beginning of another family are illustrated. Family No. 1 originated from a cow with a production record of 5,280 lb. milk, 219 1b. butterfat (21 - 505 day med. She had two daughters and one granddaughter that were its best daughters of the first sire. Family No. 2 descended frOm a cow producing 8,887 lbs. milk am his 1b. but terrat. Her daughters and granddaughters were the lower producing daughters of both sires used in the herd. A color pattern is used in the diagram to emphasize increased or decreased production. Uncanparable data is recorded in black. A de- crease in production is recorded in red, and, an increase in production is recorded in blue. Sires at the tap of the analysis are recorded in red if they decreased production. Sires that increased production are recorded in blue. Daughters of each sire are listed below his name, and, if the average fat production of the daughter is below the average of butterfat production of all tested daughters of the sire, the iden- tification of the daughter is recorded in red; if it is above the aver- age of all daughters the identification is in blue. The milk, test, and fat records of the daughter is canpared with the dam's milk,test and fat records. The records below the dam's record are recorded in red. Those above are recorded in blue. Thus, the color pattern em- phasizes cow families that are outstarxiing for high production, cow families that are mixed, and cow families that transmit low production. 145 It is noted in this herd analysis diagram that Family No. l is mostly blue, while cow Family No. 2 is mostly red. Cow Family No. 3 is not large enough to draw any conclusions from, but, with the information already expressed in that family, it would one ourage the keeping and raising of all daughters in that family. It is quite evident that we would not want a sire out of cow Family No. 2, nor would we want a son out of the poor branch of cow Family No. 1. Cow families in the herd analysis blueprint can be classified into four groups. The first group, would include families of uniform high levels of p‘oduction without reflecting the influence of sires used in the herd. These cow families show evidence of having superior trans- mitting ability. The second group would include families that show a continued in- crease in production through successive sires. These cow families show evidence of accumulating inheritance and improvement of‘transmitting ability. The third group would include families showing uneven levels of production. These cow families show evidence of heterozygous. or mixed inheritance, and, their transmitting ability is uncertain. The fourth group would include families shaving low levels of pro- duction without the influence of sires on their transmitting ability. All cow families may be classified into these groups. When study- ing different families with the knowledge of these main groups as a background, bull oomittees can develOp a keen ability in selecting out- 146 standing brood cow families to mate with herd impr over sires. Influence of Sires on Cow Families The above herd analysis clearly illustrates the influence of a sire (Sherwood Forest Judge as example) on a cow family. Comparing the daugh- ters of Sherwood Forest Judge with other individuals in Family No. 1, it is observed that their production records is considerably higher than the previous sire's daughters and the parental generation. It isiobeerved that the daughters of Judge in cow Family No. 2 are higher in production than other individuals in that family. Thus, by comparing the sires‘ daughters in each family with the previous production in the families, further evidence is obtained as to the transmitting ability of a sire. Actual comparisons of dam' and daughters' records in cow Family No.1 show that the daughters averaged 2,224 lbs. of milk and 105 lbs. butter- fat more than their dam. Also, in cow Family No. 2, there is an in- crease of 73 lb. milk and 142 lb. butterfat in the daughters' records over their respective dams. A sire with superior transmitting ability will show general im- provement in most families. A sire who has mixed transmitting ability will introduce more variations in most cow families. A poor trans- mitting sire will decrease production in most families. Influence of Cow Families on Sire Proofs The diagram on the above herd can illustrate the influence of cow families on a sire proof, and, at the same time, demonstrate that five daughter and dam coulparisons are not sufficient to base any decision 147 as to the transmitting ability of a sire. This is particularly true where sires are proven in one breeder herd. Individual cow families will not have much influence on sires proved through artificial insem- ination where dam and daughter comparisons are collected from different herds. The daughters averaged 8,876 lbs. of milk and 1415 lbs. butterfat. The dams averaged 6,652 lbs. of milk and 510 lbs. butterfat. The differ- ence is 2,221.; lbs. of milk and 103 lbs. butterfat increase. In Family No. 2 with three pairs (but we could assume five pairs) the daughters aver- age 7,1425 lbs. of milk and 595 lbs. butterfat. The dams averaged 7,552 lb. milk and 553 lbs. butterfat sharing an increase of 75 lbs. milk and 142 lbs. butterfat. Thus, in the first family, Judge would appear as a great herd improver. But, in the second family, the difference would not attract much attention to Judge as a herd improver. The daughters in the second family averaged 1,1451 lb. milk and 18 lbs. butterfat less tlrnn the daughters in Family No. l. The difference in the comparisons of these two families point out again the influence of cow families on a sire proof as explained in the previous paragraphs. These situations just described, clearly indicate that we can not base aw conclusive decisions on the amount of increase that the sire 's daughters averaged over their dams. This difference is an index, but not a decisive factor in determining the transmitting ability of a sire. Other index formulas calculated from the production records of the dams and the production records of the daughters give false evaluations of the sire, and, are of no value as a basis for selection. An example of this is clearly shown by comparing an equal parent index of Sherwood 148 Forest Judge using the two sets of comparisons as set forth above. The equal parent index in the first family would give an.index of 516 lbs. butterfat, while in the second case the equal parent index would be h37 lbs. butterfat. Other Factors in Cow Family Analysis Diagram The herd analysis diagram can include other factors essential for the improvement of dairy cattle, such as, type classification ratings, abnormal characteristics and any other factors of concern.in breeding for more efficient production. Type classification ratings added to the production records in the herd analysis diagram illustrates the transmitting ability of sires and dams for type. Careful analysis of "type" can be made with the same analytical procedure suggested for the production records. .Abnormalities such as physical deformities and lethals may be studied and removed from the herd if these abnormalities are coded and included in the herd analysis diagram. Simple factors such.as red calves in the Holstein breed can be studied and controlled‘within the herd. The herd analysis diagram.oombining the analysis of proved sires and cOW'families provides a pattern on which.the principles of genetics can be applied to reduce the probable error in selecting breeding stock of superior transmitting ability. It offers more complete information than the pedigree, the index, or a danland daughter comparison alpne. Bull committees of'the artificial breeding oocperative who are charged 'with.the reaponsibility of selecting superior transmitting sires can understand this diagram. They can observe the application of genetics £49 in a breeding program. Artificial breeding oocperatives can meet their responsibilities by encouraging record keeping whereby more information can be secured and used in selection. The herd analysis diagram does have limitations. It is limited to herds that have used a testing program five years or longer. It cannot be used in sales catalogues because of the mass of information it contains. It could be said, however, that breeders are anxious to use the herd analysis diagram in private sales because it provides greater amounts of information for sales promotion. SELECTING YOUNG SIRES Artificial insemination is reducing the number of bull calves being raised in dairy herds - that 'is with small breeder dairymen. On the other hand, young sires out of outstanding cow families and by proven sires are at a premium. The artificial breeding cooperatives must adapt a definite long- time program to deve10p a supply of young sires by outstanding proven I sires that have been analysed and used in the artificial insemination program. In addition, the herd analysis program must be developed to locate outstanding cow families to mate with the proven sires. Then a plan must be worked out to encourage breeders to develop and sample these young sires, or, the oocperative itself must make pro- visions for develoPing the young sires at the sire headquarters of the oocperative. A minimum standard of production as a basis in selecting young sires should equal or exceed the average milk or butterfat production 50 of the top ten percent of the dairy herds using the service at the present time. It is evident that the average production of the“ cows bred by sires through artificial insemination, is between 1.00- 1.25 lb. butterfat (pages 15,16,17,18,l9 of this thesis). There- fore, the base level of production on which sires are saved for artificial insemination must equal or exceed 1450 lbs. butterfat on two-time 505 day 11.3. basis. This will maintain the production level of the high producing herds using the service. Production at lower levels will tend to deteriorate the purpose of artificial insemina- tion on the oocperative plan. Selections of young sires must be based on the following speci- fications: Specifications of the Sire (parent) T. I 13.33174. proven sire with 10 or more unselected daughters average over 150 lb. butterfat - 21 - 305 day LE. basis. 2. 70% of the daughters' records should exceed their dams' records, when the dams records average less than 1425 lbs. of butterfat. 3. The production records of all daughters should exceed the breed average. 5 14. The average type classification of all daughters (2 years and Over) should equal or exceed "good‘ plus" (score 82%). 5. Be free of any breed abnormalities. - §pecificationsfiof the Dam (parent 1 1. Should be one of the highest producing daughters of her sire hav- ing the above specifications. 2. Classified "good plus" scoring 82% or higher. 51 3. Her daughters or her sons' daughters should average over breed average butterfat 21 - 505 days M.E. (D.H.I.A.) 14. Should be a member of an outstanding cow family showing a unfcrm high level of production. 5. Should have characteristics of fertility, longevity and strength. These specifications are rather severe, but, if selection committees are selecting young sires to be relatively sure of maintaining pro- duction levels of the higher producing herds who are members of the artificial breeding oocperative, they must not be too lenient. At the present time the methods. of selection has resulted in 50% of the sires raising the production over their dams. These committees must raise this probable chance of 50% to 75% or more in order to increase the supply of desirably proven sires for use in artificial breeding cooperatives. SALTLING AND PROVING SEIEQTED YOUNG SIRES The growth and development of the young selected sire is the first factor of importance. Good care and management for malnum growth is essential in developing a healthy, mature sire. Exercise, training, and controlled service before maturity will aid in maximum service and extended service as a mature proven sire. Careful training of a young sire to handle with a staff or lead rape, and, to give service by artificialcolleotion, will reduce the number of old sires that react or refuse when artificial collection is used. Therefore, the first problem of conoem to artificial breeding oocperatives after selecting young sires is to provide means for growing and training 52 young sires for maximum, dependable use as aged bulls. The second concern of the A.B. oocperative is how to sample a young sire for the quickest possible proving, in order to know what influence the sire will have toward improving the dairy cattle of the area. There are about three possible schemes which artificial'breeding oocperatives may use in sampling young sires. The first scheme would inwolve the artificial breeding oocperative by placing an Option on a.ycung sire in,a private breeder's herd. The breeder would sample the young sire and train him for artificial breeding service. An artificial breeding oocperative should make arrangements with organ- ized breeder groups, or have specific arrangements with different breeders to exchange young sires among breeders until proven or ready for artificial breeding service. The second scheme would involve the artificial breeding oocperar tive in raising young sires and using them in general artificial in- semination service. The third scheme would involve the dilution and distribution of semen from young sires to all operating units with semen from proven sires. The semen.of the young sire would be used only in tested herds on the approval of the herd owner. All of these schemes involve responsibility on the artificial breeding oocperatives in addition to the selection of sires, but, will increase their own supply of good, fertile, sound proven.sires. It is impossible to suggest any plan that could be used by all eo- operatives as each cooperative will have its own facilities and 53 relationships to work out. Statenents are made by writers and others in general conversation that it is possible to speed up the proving of sires by artificial insemination. This is true theoretically. As example, an average volume of semen collected from a sire will amount to 5 c.c. Salisbury (19h6) reported no significant difference in breeding efficiency when bull semen was diluted 1 to 100 with yolk citrate diluter. The 5 o.c.'s of raw semen would yield 500 c.c.‘s of diluted semen. Then, with one c.c. of diluted semen used to inseminate car, it is possible to breed 500 come with one service of the bull. In actual practice, this is not probable. First, let us consider the natural limitations of growth.and de- velopment of animals. A.ycung sire wi11.nct likely mature enough be- fore one year of age to provide any service. Between one and two years of age, he should be used for limited service only. By natural ser- vice in a private herd, he could be bred to 15 or 20 cows. At two years of ago, his first calves will be born. Then, from the time the heifer calves are born until they complete their first lactation on records another three years have passed. The sire is five years old by this time. A.ycung'bull in regular service with an artificial breeding cooper- ative will not likely be used before one year of age. He should be used on a limited basis between one and twoyears of age. However, he 'would be two years old before he would likely be bred to 1,000 cows by artificial insemination. It must be considered that cows are bred 5h throughout the year in order that they may freshen at different seasons to maintain a level supply of milk. Cannon 09143) (7) of Iowa reports on D.H.I.A. records in Iowa as to the intervals of V freshening. It was reported that 28.7% of the cows freshened in the winter; 20% in the‘spring; 12.2% in the summer; 29.1% in the fall. Thus, one year would elapse before 1,000 cows (explanation follows) ' would likely be bred to the young sire. According to a previous emery in this thesis, the probable neximum number of cows resulting in conception would not lihaly be over 70%. Thus 700 cows would drcp calves. Ingels of Iowa, 1956 (11) reports on a 29'year study of the Iowa .State College herd that 1,3147 calves were born in the herd during the period. The number of calves that were either born dead or died at birth amounted to 10%. About 50% of the calves born were heifers. There were 18% of the heifers born in the hard that were removed before freshening. Eleven percent of the heifer calves died before 2 months of age, and, the other 7% were removed between 19 months of age and freshening because of infertility. Out of any 700 cows that freshen, it can be expected that at least 10% of the calves were born dead. This leaves 630 living calves. The normal sex ratio (50-50) will result in 315 living heifer calves. It can be expected that 55 or 11% of these calves will die before 2 months of age, with 22 or 7% being removed after 19 months of age for infertility leaving only 258 heifers to freshen. According to the Bureau of Daily Industry D.E.I.A. letter of 55 Februany, l9h8, (5) only 3.5% of all.cows are cn.D.H.I.A.‘test in the United States. Some states have l8% of the cows on test while some other states have no cows on test. The probable number of the 258 heifers that may be tested will very in different states. However, using 5% as the probable number that will be tested, the results will be at least l0 to 12 dam and daughter comparisons of the young sire. It should be mentioned at this point that the young sire is now between 5 and 6 years of age. The third plan of distributing the diluted semen of young sires to operating circuits and inseminating cows in cooperating tested herds has considerable merit. A.young sire could be bred to l5 or more tested dams within a short period. At the end of 5 1/2 years more, possibly ten to fifteen dam and daughter comparisons could be studied. This method appears to be the most rapid of any plan or prov- ing sires. Young sires could be trained and kept free of disease, and, at the same time a breeder would not suffer a loss because of a poor sire. uh An artificial breeding oocperative would find it an unbearable ex- pense to hold any number of 2 to 5 year old sires without service until thewaere proven. The best possible plan to improve the supply of % proven sires for artificial breeding cooperatives would be to have direct contracts with breeders to sample the young sires among contract breeders, plus, the use of the young sire for antime in the sire head- quarters of the artificial breeding oocperative would limit the number of'daughters in any one herd so that a private breeder would not take the risk entirely. 56 The owner-sampler plan or increasing the number of herds on test by D.H.I.A.,E.I.R., will do more to speed up and increase the supply of proven sires than their use by artificial insemination. 57 001101113; gigs . The responsibility of artificial breeding oocperatives for the improvement of dairy cattle depends on the good judgment of the sire selection committees to deve10p, preserve and make available to all dairymen the superior germ plasm of outstanding sires. The amount of improvement of dairy cattle in a community will depend on the follow- ing fact crs : l. 3. The size of herds using the service of the oocperative. It was shown in Table 1 that about 80% of the total cows in a dairy community were in herds of ten cows or more. As example in New Castle County, Delaware, 83% of the total cows were in herds of 10 cows or more, while 70% of the total cave bred artificially were in 10 cows or more. This cmdition may be considerably different in other communities. The rate of conception by artificial insemination shall continue to control the success of the oocperative plan. Continuous studies must be made by the oocperative to compare the average breeding results of artificial insemination with the average breeding re- sults by natural service. They should be equal. This is not true in individual herds. As shown in Tables 2 and 3 in New Castle County, Delaware, 19147, there were. 814% of the herds showing re- sults equal to or better than natural service while 16% of the herds had poorer results than natural service. . Sires used in artificial breeding oocperatives are being mated to cows that average between 1400 and 1425 lbs. of fat. See pages 15, 16,17,18,19. 58 Therefore, the level on which sires are to be selected must exceed this level of production. Not all sires that are proven can maintain 1400 lbs. of fat as shown in Table 14. 14. 5. b. 7. Dairy Herd Improvement Association or Herd Improvement Registry programs are best adapted for proving sires, proving cow families, and measuring the improvement of dairy cattle by artificial in- semination. Sires are 5 to 6 years of age before a sufficient number of’daugh- ters have chleted production records, which will determine the transmitting ability of the sire. About 1/5 of the sires proven in Dairy Herd Inprovenent Associations are still living. About l/2 of those sires still living are available at the present time for service in artificial breeding oocperatives. There is need for sires to be developed and saved for artificial breed- ing service. The best method for analyzing the transmitting ability of a sire is by direct comparison of dam and daughter records. This analysis should include a study of environmental conditions, comparison of records of the dams and daughters with the breed average, percent- age of daughters exceeding their dams, variations of. records of the dams and daughters as to their rangefrom the lowest record to the highest record, and, the level of production at which a "Breaking point" appears. DeveloPment of herd analysis diagrams to determine the breeding history of the herd and the development of cow families. Cow families are classified into 14 groups, namely; families that transmit 59 a uniform high level of production; families that show a continued in- crease in production through successive sires; families that show un- even levels of production; families that show levels of production and are not influenced by sires of low transmitting ability. 8. 9. 10. ll. The herd analysis diagram combines the study of proven sire analysis and the cow family analysis. This herd analysis diagram is used to determine the influence of sires on cow families, and, the influence of cow families on the dam and daughter comparisons of a sire. The herd analysis diagram (see page 145) can include other factors such as type classification ratings, abnormal characteristics, and other hereditary characters that may be controlled or deveIOped. Young sires are selected on the basis of the analysis of proven sires and cow families as illustrated in Table II. The young sire is sired by proven sire who had demonstrated superior trans- mitting ability and out of a cow family that transmits a high level of production. Artificial breeding cooperatives should follow a program of train- ing and developing young sires for maximum and extended use as proven sires. Three plans were suggested, namely; (l) a direct contact between an artificial breeding oocperative and private breeders, (2) cc-Operatives purchase young sires and use them in regular artificial insemination service, (5) oocperatives purchase young sires and breed cows in tested herds only. 60 12. The most rapid method of proving young sires is to breed fifty 15. ill. to sixty cows in tested herds as soon as possible after the young sires become of service age. This will reduce the risk of am one breeder and make it possible to prove the sire with- in 14 1/2 and 5 1/2 years of age. It is suggested that young sires between 2 and 5 years of age be exchanged either between artificial breeding cooperatives or private breeders in order to reduce the overhead of carrying a battery of young sires until proven. Increasing the number of herds m D.H.I.A., H.I.R., or owner- sampler test plans to increase the supply of proven sires and to measure the improvement by artificial insemination. lo 2. 3. 14. 5. 6. 7. 8. 9. 10. {21 REFERENCES Albrectsen, R.A. Selection and Repeatability of Sires Used in Artificial Insemination. Journal Dairy Sci.,Vol.50,No.8,P.5914-August Bartlett, J. W. Test Tube Cows Excel in Volume of Milk Pro'd. 191414 - American Milk Review, Vol. 6 (12) Bureau of Dairy Industry Dairy Herd Improvement Assoc. News Letter 1% . VOL. 22 NO. 5 M Bureau of Dairy Industry Dairy Herd Improvement Assoc. News letter 1947 - Vol. 25 No. 6 June Bureau of Dairy Industry Dairy Herd Improvement Assoc. News letter 19148 - Vol. 214 No. 2 February Bureau of Dairy Industry Dairy Herd Inprovement Assoc. News letter 19148 - Vol. 214 No. 5 March Cannon, C.Y. and Hansen, Edi. Freshening Date Changes of Cows in Iowa Dairy Herd Improvement Association. 19145 - Jo. of An. Science 2 (2) 112-117 2 r 19 Davis, H.P. and Trimberger, Geo. W. Conception Rate in Dairy Cattle by Artifi- cial Insemination at Various Stages of Estrus. 19145 - Research Bulletin Nebraska Ag.Ex. Sta. 129 1-114 Hilder, R.A., Fohrman, 11.3., and Graves, R.R. Relation of Various Factors to Breeding Effi- ciency of Dairy Animals and to the Sex Ratio of the Offspring. 191414 - Jo.Dairy Sci. 27 (12) 981-992 H1111" FeEe, Dunnock, WeWe. Ely, Fordyce, and Morrison, HOBO Re roductive Efficiency in Dairy Cattle. l 0 - Kentucky Agric. Ex. Station Bulletin 1402 161-188. 110 12. 13. 15. 1.60 l7. l8. 19. 62 Ingels, John, and Cannon, C.Y. The Mortality of Calves in the Iowa State College Dairy Herd. 1956 - Proceedings, American Society of Animl Production, December. Lush, J.L. and Nelson, R.H. . Mdthods Available for Measuring Transmitting Ability in Sires and Dame. 19143 - (unpublished) paper presented Amer. Dairy Sci. Assoc. annual meeting - June. 140811, JQL. Animal Breeding Plans - Third Edition. Collegiate Press, Inc., Anise, Iowa. Morgan, R.F. and Davis, H.P. Influence of Age of Dairy Cattle and Season of the Year on the Sex Ratio of Calves and Services Required for Conception. 1958 - Research Bulletin Nebraska Agric. Exp. Station 104 l-l9-38. R106, VOA. Breeding and Improvement of Farm Animls. 5rd Edition - 191.12 - MoGram-Hill Book 00., N.Y. Rice, VA. A New Method for Indexing Dairy Bulls. 191411 - Journal of Dairy Sci. 27 (11) 921-936 Fertility of Bull Semen Diluted at 1:100. 1.9146 - JO. Dairy $01. VO1. 29 (1.0) OOt. UOSODOA. Farmers Bulletin NO. 19714 The Dairy Herd Improvement Assoc. Program U.S. Census Report 1940