THE. INFLUENCE OF STORAGE 0N HATCHABIUTY 0F RINGNECK PHEASANT EGGS . Thesis for the Degree of M. S. MICHIGAN STATE. UNIVERSITY DAVID ALLEN DORN 1976 IIIIII H3 I I III I R” I IIII 31293011 4 5 I III III FEB a r 1996, ABSTRACT THE INFLUENCE OF STORAGE 0N HATCHABILITY or RINGNECK PHEASANT EGGS BY David Allen Dorn An attempt was made to determine if there was any effect of storage on hatchability. Beginning on May 2h, l973 through October 23, 1973 (for 2h weeks), a total of 20,000 (twenty thousand) ringneck pheasant eggs (Phasianus colchicus) were gathered, stored and set every two weeks. Results of the hatches were analyzed as to (a) the effect of storage on hatchability and (b) the influence of storage on mortality of the embryo during the three critical periods of incubation. The analysis of storage on hatchability revealed a significant decline in hatchability commencing on the tenth day of storage. This revelation parallels the results obtained by other researchers investi- gating domestic poultry Species. The examination of the relationship of storage to critical stages of mortality revealed some degree of significance, but insufficient proof to inculpate storage as a critical factor. However, on closer examination, mortality was more prevalent in the initial critical stage of incubation than the other two critical stages. THE INFLUENCE OF STORAGE 0N HATCHABILITY 0F RINGNECK PHEASANT EGGS BY David Allen Dorn A THESIS Submitted to Michigan State University in partial fulfillment of the requirements ' for the degree of MASTER OF SCIENCE Department of Poultry Science l976 ACKNOWLEDGMENTS The author is indebted to the Wildlife Division of the Michigan Department of Natural Resources for the utilization of the pheasant put-take facilities to carry out this endeavor. Appreciation is extended to the personnel at the breeder-hatchery unit in Mason, Michigan for their assistance in compiling the raw data. A special note of appreciation is extended to Drs. Charles Sheppard and Cal Flegal of the Poultry Science Department for their careful guid- ance and consultation. Their expertise was available not only during the completion of this manuscript but throughout the pursuit of my Master's degree. The author extends thanks to Dr. Larry Dawson of the Food Science Department for his valuable criticism and comments. To Dr. Howard Zindel, Chairman of the Poultry Science Department, sincere thanks is extended for his advice and consideration during this period. Finally, the author is indebted to his wife, Hazel, and son, David II, for their understanding and encouragement during this time of study. Also, Special thanks to my wife for her typing of this work which helped to bring this effort to a successful conclusion. TABLE OF CONTENTS LIST OF TABLES AND FIGURES . . . . . . . . INTRODUCTION . . . . . OBJECTIVES . . . . . LITERATURE REVIEW . Temperature . . . Humidity . . . . . Storage effects on Pretreatments METHODOLOGY . Collection of Data . Analysis of Data . RESULTS AND DISCUSSION the embryo . . . . Effects of Storage on Hatchability . . Effects of Storage CONCLUSIONS . . . . . . LITERATURE CITED . . . on Stage of Embryonic Mortality . WPW l2 l2 in I7 I7 25 as A7 Table IO. ii. l2. 13. lh. '5. l6. I7. l8. ‘9. LIST OF TABLES AND FIGURES Composition of breeder diet . . . . . . . . . . . . . Guide for incubation of pheasant eggs Percent hatch of total eggs set versus percent hatch of fertile eggs . . . . . . . . . . . . . . . . . . . . Percent hatch by day of storage of all eggs set during trial 0 O O O O O O O O O O O O O O O O O O O O O O 0 Average hatchability of ten hatches throughout treatment perIOd O O O O O O O O O O O O O O O O O O O O O O C 0 0 Analysis of variance for data taken from Table A . . . . Dunnett's T test of influence of storage on hatch (Day l control) 0 C O O O O O O O O C C O O O O O O O O O O O 0 Comparison of l-lh day storage versus l-iO day storage . . The effects of hatchability on pheasant chick cost . . . Percentage of infertile eggs during trial period . The influence of storage on stage of death in hatch #2 . The influence of storage on stage of death in hatch #3 . The influence of storage on stage of death in hatch #h . The influence of storage on stage of death in hatch #5 . . The influence of storage on stage of death in hatch #6 . . The influence of storage on stage of death in hatch #7 . The influence of storage on stage of death in hatch #8 . The influence of storage on stage of death in hatch #9 . Chi-square analysis of pooled embryonic mortality during Page . . 15 I6 19 20 2| . 23 2h . 26 27 . . 29 . 30 . 3i . 32 . 33 . 3h . 35 . 36 . 37 . 38 eight hatch period . . . . . . . . . . . . . . . . . . . . V 20. Percentage of embryonic mortality affected by stage and day of storage . . . . . . . . . . . . . . . . . . . . . . . ho 21. Analysis of variance of data in Table 20 . . . . . . . . . . hi 22. Orthogonal contrast from analysis of variance derived from Table 2] O O O O I O O O 0 O O O O O O O O O O O O O O O I 0 AZ Figure 1. Average relationship of percent hatchability to length Of storage . . . . . . . . . . . . . . . . . . . . . . . . 22 2-7. Illustrations of three critical stages of embryonic mortality a o o o o o o o o o o o o o o o o o o o o o o o “3"LES INTRODUCTION This research developed as a result of action taken in part by the Michigan State Poultry Science Department and the Michigan Department of Natural Resources. Initially the poultry science personnel had become involved in pedigreeing Chinese Ringneck Pheasants (Phasianus colchicus torquatus) in order to improve egg production under totally confined conditions using proven techniques employed by the domestic poultry industry. Also during this period, the Wildlife Division of the Department of Natural Resources was exploring alternatives to increase the dwin- dling native pheasant population at a time when hunter numbers were escalating and hunter success and satisfaction was on the wane. The current trend of vast farm ownership, less crOp diversification and the ever expanding encroachment of urban Sprawl did not hold a very bright prOSpect for sustaining present pheasant populations. In order to combat this situation, it was proposed that the state of Michigan initiate a put-take pheasant project. The program was explained in Pheasant Stocking Proposal Section 36 Act l33 Public Acts of l97l. Included were three main objectives: l. Substantially increase pheasant hunting on designated state game and recreation areas 2. Increase the annual harvest by l00,000 or more 3. Provide increased hunter satisfaction 2 The legislature approved the measure and granted funds for a hatchery and a rearing unit with plans of a l00,000 bird release in l973 and l974 and eXpanded to 200,000 by l975. The limitation of funds caused the rearing facilities to be limited in its capacity for handling weekly hatches. Thus, it was decided to initiate a bi-weekly hatching schedule with the first hatch scheduled for March, 1973 and the final hatch for October, l973. This gave rise to the need of storing eggs for 1A days prior to incubation. It is with this background information that the research was recom- mended by Drs. Charles Sheppard and Cal Flegal of the Michigan State Poultry Extension. Many researchers have investigated the length of storage of eggs on domestic poultry and concluded that the profitable level of holding eggs prior to setting was l0 days or less. Gowe et al., (1965) was able to significantly improve hatchability by use of artificial means such as flushing settable chicken eggs with nitrogen and encasing them in plastic. However, very little substantial material was available concerning the effect of storage on game bird hatchability. Consequently, the decision was made to investigate the role of storage on pheasant eggs to determine if there were any deleterious effects. It was also suggested that we examine the stage of death of the embryo to ascertain if there was a relationship to storage. Romanoff et. al., (l93h) had observed at least two and possibly three periods in which the embryo is likely to eXpire. These are classified as critical periods and under normal development usually occur on or near the hth, l2th, and 23rd day of incubation. OBJECTIVES What, if any, are the effects of storage on the hatchability of ringneck pheasant eggs? Is there any significant difference in the distribution of embry- onic mortality during the various stages of incubation due to storage? What is the influence of storage on costs? LITERATURE REVIEW Temperature ”Due to the physical limitations of the hatching egg, prolonged storage leads to teratological (abnormal) conditions,“ Romanoff et al., (1938). The successful storage of hatching eggs is highly dependent on the environmental temperature of the storage area. Asmundson and Mclleath (1939) reported that the holding of turkey hatching eggs at 69° F (21° C) for the first two days following oviposition need not be detrimental to hatching potential provided the eggs are subsequently stored at 55° F (12.7° c). Farnsworth (1962) discovered that delayed refrigeration at 55.A° F (130 C) resulted in less apparent fertility after nine days of storage. Eggs refrigerated the same day of lay produced a higher percentage of marketable chicks than eggs with delayed refrigeration. Funk (1934) has recorded a gradual decline in hatchability as it is likely to occur at an environmental temperature of A50 to 600 F (7.20 to 15.50 C) for a period of 31 days. The percentage of fertile chicken eggs hatched ranged from 76.2% (0-7 days), 7h% (8-lh days), 32% (22-28 days), and 0% (29-31 days). Olson and Haynes et al., (l9h8) suggested that at an optimum range of 50° to 55° F (100 to 12.80 C), hatch of eggs stored for one week favored the higher temperature and subsequently the lower temperature enhanced hatchability of eggs held 5 longer than one week. Proudfoot et al., (196A) reported a temperature and storage interaction of similar nature. It is apparent from these findings that the first requirement for successful storage of hatching eggs is maintenance of an optimum range of temperature. However, the temperature should be kept below a point at which embryo deveIOpment commences. This point has been called ”physiological zero.“ This threshold for chicken eggs was established by Edwards et al., (l902) between 68° and 700 F (200 and 210 C), but more recent research work by Funk and Biellier (l9hh) established that it is several degrees higher. North (1972) Commercial Chicken Produc- tion Manual, records the threshold at 75° F (21+o c). However, he asserts that the embryo in a freshly laid egg is slightly cold blooded, therefore one may alter its environmental temperature above or below the threshold area several times before the embryo is completely killed. Romanoff (l93h) accentuated the importance of optimal temperature as it inhibits the diffusion of water from the albumen into the yolk. Hender- son (l9h2) reported that the more mobile the yolk was, the less hatch- ability. He also found that yolk mobility increased with pre-incubation age. Humidity Moisture held within the contents of the egg is continually lost by evaporation due to the porosity of the shell. (If the shell is highly porous, substantial amounts of H20 loss occurs over a short period of storage.) The rate of evaporation is governed in part by the relative humidity of the air surrounding the egg: when the humid- ity is low, evaporation of the egg contents is more rapid; when it is high, evaporation is less rapid. Funk and Forward (1951) concluded 6 that a relative humidity of 80 to 88 percent resulted in higher hatch- ability than did the lower humidities (58 to 62 percent). North et al., (1972) maintains the relative humidity of the air in the holding room should be 75 to 80 percent. Carter and Freeman (1969) suggested that Proudfoot found that eggs stored for three weeks at 75 to 80 percent relative humidity tended to hatch somewhat better than eggs stored at the lower humidities. Storage Effects on the Embryo Kosin (1956) found that it can be tentatively assumed in fertile turkey eggs, at time of oviposition, there is considerable variability in the degree of embryonic deveIOpment. It is assumed that turkey eggs of high hatching potential contain blastoderms in more advanced stages of development than do eggs of lower hatching potential. The report of Bernier et al., (1951) suggested that the mean blastoderm size of the egg is an individual hen characteristic and appears to support the premise of an optimal stage for withstanding the effects of post-ovi- posital cooling and storage. Becker and Spencer (196A) suggested that C02 gaseous exchange between the environment and the content of the egg was one of the factors affecting the embryonic viability of turkey eggs stored over a long period. Landauer (I967) reported that Kaufman dis- covered that after prolonged storage embryonic mortality was eSpecially high in early stages of incubation. The researcher also found: I. Hatching was delayed. 2. Initiation of development was retarded. 3. The water was increased in the yolk and decreased in the albumen. Body size of the 7 to 1h day embryo was considerably reduced, but the 7 relative growth rate was higher during the last two weeks of incubation in embryos of stored eggs than those in the control group. Boca (1862), as quoted by Lippencott (1933), observed that a blastoderm of 27 days of age at the time of setting frequently developed for a short period of time, then died. Storage of eggs also appears to affect the body weights of chickens eight to nine weeks old. According to Becker (1960) in four experiments using meat type chickens, the body weights of chickens hatched from eggs stored for at least two weeks before incubation were significantly lower than the body weight of chickens from eggs stored less than one week. Pretreatments l. Preheating Becker and Bearse (1958) found that chicken eggs that had been stored three to four weeks profited most by preheating. Kosin (1956) subjected chicken and turkey eggs to daily warming to simulate outdoor temperature fluctuations and also to a single warming period (two to five hours) at 99 3/h° F (37.50 C) followed by storage at 55° F (11.50 C), and reported that the hatchability of both was improved, eSpecially that of turkey eggs. That pre-warming treatment of eggs to be stored for one week does not enhance hatchability has been shown by McConachie et al., (1960). It appeared that a constant temperature of 53° F (15.50 5) without preheating was superior for short terms of storage. However he postu- lated that this difference may have been due to the different breeds involved. 2. Freezing Funk et al., (1950) discovered when eggs are held at or below the freezing point for longer than two days, hatchability deteriorates progressively, but brief exposure to very low temperatures may be tolerated without damage. Eggs from genetically different stocks of fowl may, according to Olsen (l9h8), vary in the degree of damage done by storage for three to five days at 320 F (O0 C). 3. Turning Funk and Forward (I951) asserted that turning is beneficial when eggs are held longer than one week. These conclusions are supported by the findings of Proudfoot (1966) who reported that turning improved hatchability significantly in eggs held for more than two weeks. Turn- ing aids in centralizing yolk position, thus preventing adhesion to the inner shell membrane. A. Artificial Storage Methods Landauer (1967) reported that as early as 1738 deReamur suggested the use of mutton fat for dipping eggs to prolong storage life. When the eggs were to be incubated, the fat was removed with warm water. More recently other methods have been devised for sealing the shells of hatching eggs to aid in the preservation of interior quality. Becker (196A) and Proudfoot (1966) reported that encasing hatching eggs in plastic during storage enhanced hatchability, being more advantageous if storage time was prolonged and a high pre-incubation temperature (22.20 C) was prevalent. Gordon and Siegel (1966) stored pedigree eggs enclosed in Cryovafl for one to four weeks and determined that hatchability of fertile eggs could be improved by airtight packaging. The type of permeability film was examined by Proudfoot (1966) who 9 reported that a lower permeability film was more effective in improving hatchability than a high permeability film. Gowe et al., (l965) and Proudfoot (1966) compared storage of eggs for 19 to 2A days in Cryovac with nitrogen and Cryovac with air. The storage life in the nitrogen atmOSphere resulted in a 15% higher hatch. Bowman (1966) examined these two regimes and found that the hatch- abilities were not significantly different. However, he found chick quality was markedly better with the nitrogen packing treatment. Al- though some inconsistency exists among reports, there is strong evidence that if hatching eggs are to be stored for longer than three weeks in Cryovac-enclosed packing, hatchability can be improved by flushing the storage area with nitrogen gas. One theory behing these pretreatments is their ability to inhibit the loss of a proper gaseous environment for storage. Although an optimum gaseous environment has not been established, researchers have presented limited evidence as to the effects of carbon dioxide and oxygen (main gaseous components) on storage life of hatching eggs. Proudfoot (1966) demonstrated that high levels of carbon dioxide had no detrimental effect with eggs stored for one week or less but severly depressed the hatchability of eggs stored for longer periods. However, a low level of C02 is necessary to prevent a sharp rise in the pH of the albumen (Romanoff and Romanoff, l9h9). Sadler (l95h) advanced the theory that one possible role of carbon dioxide during early embryonic deveIOpment was to aid in retarding the dissolution of the chalazaferous membrane which proteces the embryo during the first 72 to 96 hours of incubation from contact with the thin inner albumen. Spencer et al., (1968) demonstrated that the pre-incubation packaging of eggs tended 10 to stabilize carbon dioxide in the albumen after two days resulting in a more optimum prolonged storage. However, Kosin and Konishl (1973), in examining the C02 storage interaction, found that the carbon dioxide concentration in the egg albumen was not a major factor for maintaining the inherent capacity of the egg to hatch following pre-lncubation storage. Oxygen requirements for storage have not been determined. How- ever, Proudfoot (1965) presented evidence that indicates oxygen tended to stabilize at the A percent level after four days of storage in the nitrogen flushing technique. His work was supported by Spencer and Swartwood (1968). Although some inconsistencies exist, it becomes apparent that low levels of carbon dioxide and oxygen contained within plastic enclosures flushed in nitrogen provide optimum conditions for extended storage of hatching eggs. North (1972) advanced the theory that after a few hours in lines cases, moisture escaping from the eggs raised the humidity. This, in turn, aided in slowing further egg evaporation. This method resulted in prolonging the hatching quality of the eggs and significantly in- creased hatchability. A recent report by Kosin (l973) tends to support this hypotheses. 5. Storage of Eggs Small End Up Rezzler (l97h) presented research by Proudfoot showing that hatch- ability could be increased by storing eggs small end up and not turned, then turning them to the traditional small end down position at time of traying. The reason being that the yolk tends to rise to the small end during storage and settles back to the central position during incubation. This position by the yolk in relation to the albumen affords the dormant ll embryo with greater protection from dehydration, temperature change and adhesion to the inner shell membrane. METHODOLOGY Collection of Data Beginning on May 2A, 1973 through October 23, 1973, data were accumulated (for 2h consecutive weeks) on pheasant eggs which were gathered, stored and set every two weeks. The results of the sub- sequent hatches were recorded as to (a) effect of storage on hatch- ability and (b) the influence of storage on mortality of the embryo during incubation. The eggs originated from 1800 pheasant breeders which were subject to similar conditions except for a variation in light treatment. They were housed in five ho x 50 ft. (12.2 x 15.25 m) light controlled pens, and given feed and water 2g libitum (Table l). The lighting scheme consisted of a 1h hour light period and a 10 hour dark period with a light intensity of one-half to one foot candle at bird level. The eggs were gathered daily at 8:00 a.m., 11:00 a.m., 2:00 p.m., and A:OO p.m., seven days a week. They were collected in egg flats and placed small end down. Each flat was recorded as to pen and date. The eggs were moved to the hatchery room where they were gradually cooled to prevent undue shock to the embryo, keeping in mind that the embryo had already undergone several hours of incubation and is a living organism sensitive to sudden extremes in temperature. They were then tranSported to the storage area which consisted of a 10 x 20 ft. (3.05 x 6.1 m) cooler controlled by an industrial refrigeration unit. 12 13 Although the eggs were not graded according to size; checks, cracks, and extreme dirties were discarded while other eggs were hand sanded to remove possible contaminants. The environmental storage conditions included: A. 50-55° F (9.9-12.l° c) B. 70-75% humidity C. Turning the eggs approximately 45° once daily After the eggs were accumulated during the fourteen day collecting period, they were removed from the cooler to the hatchery room and placed in the incubator trays. All eggs gathered on one day were set in the same tray. This gave rise to IA trays, which is the capacity of the Jamesway 252-8 incubator. The trays of eggs were left outside the incubators over night to assist the viable organism in a gradual warming process to prevent the shock of 1000 F (37.70 c) incubator temperature directly from the storage environment. The next morning the trays were randomly placed in the incubators. The eggs were hatch under conditions established by the temperature, humidity and ventilation guide of the Jamesway manufacturers (shown in Table 2). 0n the let day of incubation, the eggs were transferred into baskets for the final stages of hatching. The pheasant chicks were taken off after 2h days of incubation and recorded as to the correSpond- ing day set. All other eggs were broken out on the 25th day and examined macroscopically to determine if the eggs were infertile, or if growth had been initiated, or at what stage the embryo expired. The terms or “critical stages” of incubation were separated into three groups: I. lst stage - 2h hours-8 days 2. 2nd stage - 9-17 days 3. 3rd stage - 18-2h days 1h Each stage is characterized by at least one distinguishable trait which will be indicated by illustrations (Labisky and Opsahl, 1958) in the Results and Discussion. Analyses of Data Data were analyzed by the use of analysis of variance to test for any significant effect of storage on percent hatchability. To determine at what point the storage length factor became significant, the Dunnett's T Test was employed. The stage of death versus length of storage was examined by use of chi-square analysis. An orthogonal test was arranged to ascertain any difference between the three critical stages of embryonic mortality. 15 Table 1. Composition of breeder diet Ingredient Percent of diet Corn 29.7 Ground oats 25.h0 Bran 3.6 Meat 5 bone scrap 2.5 Soybean oil meal (h9%) 29.0 Delactosed whey 2.5 Dicalcium phOSphate 2.1 Calcium carbonate “.3 A to Z vitamin concentrate .5 Salt .h 100.00 Protein 19.0 Fat 2.85 Fiber 5.22 Calcium 2.AO Phosphorus .69 Methionine .3A Methionine 6 cystine .70 Metabolizeable energy, Cal/lb. 1150 l6 Lozoumzneoumnnuc_ amoumuo_mcmm NmN .060: Law conga comum__uco> ocm >u_v_E:: .ocaumcooth EoLw cox—wkbe umzmcxo coco op_3 no.3 n.3a um: oom OH omm on p.303 .mop. 0mm um n.3n uoz 0;“ v_oc Ou omzmcxo coco 0mm mocomoc >u_o_E:; cog: mc_;ubm; mc_.:a .>a_e_e=; v.0; op smaOco >_co mum—muco> mc_coao :e\_ ob :m\_ mc_cooo :w\_ mc_cooo :m\_ Cu nomo_u .mucmum mc_ icoum; cos; oom 0» o: oo cu a. zo__m ocm cow 0“ a: >u_p_E:; mc_cn Lummcmcu coum< com 0mm-on 0mm-o~m owe oe\m mm mc_;opm: 0mm A>ma eCNNV tocmcmtu emote o:\m mm commcmcu 0» >mp cum— ooo_ >mp su~_ op >66 pcm coo. >mp pen 0» >mp um— mc_uuom umamsxm ocaumLmank n.3m um: ocaumcanmh n_:m >Lo mmmo ucmmmoca mo co_umn:uc_ Lo» ou_:u .N o_nmh RESULTS AND DISCUSSION Effects of Storage on Hatchability Hatchability of pheasant eggs can be described by at least two different methods: 1. Number of chicks hatched as a percentage of all eggs set 2. Number of chicks hatched as a percentage of fertile eggs set It has been observed by this researcher that in order to obtain a more accurate appraisal of hatching analysis, it was necessary to pre- sent the hatching data as a percentage of all eggs set. It is very difficult to determine fertility of pheasant eggs with any degree of reliability by the candling method. The normal color of the pheasant egg ranges from all hues of brown to shades of olive drab, thus pre- cluding any effective candling to determine fertility. Consequently, fertility had to be ascertained during the breakout of all eggs follow- ing 25 days of incubation, giving rise to the distinct possibility of failing to distinguish between a definite appearance of a blastoderm or a massive breakdown in the components of the egg. This can be more fully appreciated by understanding the total time lapse for a 1“ day old egg before incubation would be as much as ho days, including incubation time. This finding is in agreement with Landauer (1967) who, working with chicken eggs, I'found the extent to which prolonged storage interfers with development may exceed the figure reported in the literature since a gradually increasing 17 18 proportion of eggs will never start development and hence be likely classified as infertile.” Although all data pertaining to hatchability will be reported as percentage of all eggs set, Table 3 shows the per- centage comparison of the two different methods over a ten hatch period. Table A shows the percentage hatch of all eggs set for the total period under consideration. Upon observation, the reader will note a fluctuation in the over-all hatching percentage during the trial. The author postulates a possible attribution to the procedure of exempting males from a pre-lighted treatment, thus causing infertility. However, as the light treatment program for the pen progressed, the shortcoming was over come with more satisfactory fertility results ultimately lead- ing to a better percentage hatch. The average hatching percentages of the ten hatches during the trial are detailed in Table 5 and Figure 1, showing an approximate decline of over 17% during the trial, with the sharpest drop occurring between the 10th and lAth day. To ascertain the presence of any significant statistical effect of storage on hatchability, an analysis of variance (Snedecor, 1968) was employed. The results are summarized in Table 6. There was suf- ficient evidence to conclude that a significant difference does exist in the mean reSponse of the treatment groups. To determine at what point storage became statistically signifi- cant, Dunnett's T test was used (Dunnett, 196A). This sensitive statistical tool was employed to test the mean of the control versus the mean of each experimental group. The control group was the eggs stored for only one day. The results in Table 7 show that the 19 .Ao_n_m_> acoan_o>oo OcV co_umn:uc_ mo m>mp :u coumm umc_ELouop >__mu_ooomoLomz« a.mn n._m mom mmm_ o— w.mw mm.o~ amo_ mm:_ m :._m _m.om mow_ .mmm m w.mn mm._m _Nmp mmdm N om.on mm.mm mm__ o:_~ w ma.m~ _m.mw .mwp mmmm m ~N.NN d_.mm m_m_ woom J mime a.m.m mmf mwom m m.on um._w mwm_ m_nm N m._n _.mm :mm. :mmm _ mmmu #o__ucou mmmw _muo» mxu_;u uom mmmm .02 zoom: noun: ucoocom Loam: Hampton _ou0F .mu0k mama «o__ucow mo Loom; ucoocoa mamco> uom mmmm .nuou we soup; acoucom .m o_nmh 20 mo_mE mc_u;m__uoca unecumz xoo_m vm_o>oom¥ m m z u k < : mm.:m N¢..~ m._m om.oo o~.:m Nm.mo m_.mm mo.mm ~.~o m~.eo ammca>< .mqmw dqmm mqu. WIMN quw “dam. mqmm. mqmw. mamN. mqu. _ o.mm m.mw m.:m 4.:m m.mm m.mw m.mo ~.Nm m.on a.mo N M.Ka 0.0“ m.e~ m.mm m.mm «.mo :.No ~.~e a.mo a.mk m m.mo 0.0“ a.mm m._N a.mo m.0~ o.~m a.mm m.mo ~.~o : m.mm 0.0m ~.om m.:~ _.oo a.mo ~.ow o.m: 0.0m ~.on m nu ode 3.: 5i mam 5mm «Jo 9mm 0.? 53 13 w m we... oi .93 as «23 Q: 3m 3m 3m :2 N w. ~.mm m.m~ m.Nm m.mm m..@ m.@@ ~.om m._m m.~w m..@ m m w.mm ..mm ~.mm m.mm a.ma o.ao ~.mm ~._m m.mm m.~m m ,% _.em _.eo m.eo m.mm m.mm a.mo ~.~m o.am m.mm ~.mo o. e.Nm A.m~ a.mm _.me _._m a.mo a.mm a.mm m.~m ~.om ._ ~.~m ~.mm m.o~ a.me m.mm o.ao a.me ~.wm e._o o.am N. m.um m.mm m.om _.m: N.m: ~.¢m m.:: m._m a.mm m.:m m— w.m~ a.mo a.mm m.~e a.:: ~.mm m.me m.ma a.mm m._o a. a.o. m m n w m a m N _ ucoeumock .mmcu mc_c:v “on name __m mo ommLOHm mo >mp >3 Loam; acoucom .: o_amp 21 Table 5. Average hatchability of ten hatches throughout treatment period Days in Storage Average Percent Hatch \nrw 10 11 12 13 1A 69.91 66.83 63.67 67.15 65.6 65.6 62.8 62.3 60.19 59.15 57.2 55.87 5A.66 52.03 22 m o < m o h m z _ m > < a 4— m_ N. __ o. m m N m m J m N _ com m SJ .am/fi mm mm Km /_$/ p.00/ 00 m.~miw.~e m.mm .mwio. /$ mo 93/ _. a.mm ox ommcoum mo sumac. cu >u___nm;uumz acoocoa mo a_;mco_um_oc ommco>< ._ ocam_u H 3 l V H l N 3 3 H 3 d 23 Table 6. Analysis of variance for data taken from Table A Degrees of Sum of Mean Source Freedom Squares Square F-Value * Hatch 9 .65367 .0726 25.03 * Day 13 .30897 .0238 8.21 Error 117 .33606 .0029 *Significant at P< .Ol 2A Table 7. Dunnett's T test of influence of storage on hatch (Day 1 = control) Number of Days of Storage T Statistic 2 -.108679 3 1.26158 4 -.IOSA9S 5 1.35151; 6 .956882 7 1.70208 8 ' 1.88708 9 2.76311 a 10 3.22528 ab 11 A.05312 ab 12 A.60607 ab 13 5.11366 ab 1A 6.2056 ab a denotes significant difference at P41.05 b denotes significant difference at PeL.Ol 25 influence of storage on hatch for days 9-1A (P .05) and lO-lA (P .01) were different when compared to the control. The results of this experiment parallel those found by Woodard and Morzenti (1975), who investigated the effects of storage on percent hatch of pheasant and other game birds, which indicated a significant decline in the hatchability of pheasants eSpecially after a 13 day storage period. The economic effects of storage can be shown by comparing the cost of a l-IA day hatch period versus a 1-10 day hatch period (Table 8). Table 9 shows an approximate 3%.loss in salable chicks during the 10 hatch period. Expanding this difference to include the entire hatch- ing season, utilizing all available data for the year, indicates a higher cost of chicks for the l-lA day storage period. Table 9 also shows the variations in cost to produce a chick when the two groups of eggs have the same cost but different hatchabilities. Over the total hatch period a difference of l.7¢ per chick is found. Therefore, It can be stated that the greater the percentage hatched, the lower the cost per chick. Increased income from 1-10 day storage period can be shown as follows: Assume: 60¢ sale price per chick Given: 3,118 chicks (65,A92-62,37A) .60 $1,870.80 In addition, given cost difference per chick: .017 x62:35A(l-1A day storage) $1, 0 O 3 Calculation shows: $1,870.80 1,060.36 $2,93l.l Increafied lncom me from 1- -'Od. day storage over t e tota? hatch pero 26 a.mm mmm.o_ mm~.~_ n.om nmm.e_ mom.a~ a.muoe a aim: my... mum... gum... mm... 2 m.- mam Nam m.o~ ewe. mwa_ m 0.:N :wu. wmn. m.o~ mow. mmmu m ~.Ne m_~_ ~_m_ ~._m .Nm. mmam A m.mm omw mos. a.mm mm__ o:_~ m a.me m_~_ mum. m.mo .mm_ mme m ~.om _m~_ ~a_~ _.~m m_~_ moan a m.~m _e__ _o~N m.~m mme_ mmom m a.mw Nm__ _Am_ m._o mam. m_N~ N a.mm mmm_ m~_~ _.mm :mm_ ammw _ gape: mxu_;u pom Loam: mxu_;o 6mm Loam: acoucom mmmu ucoocod mmmm msmo o_-_ msaa a.-. ommeoum >mv o_n_ msmco> ommcoum >mp d_i_ mo com_LmQEoQ .m o_amh 27 >meu_nco oco mumoo mcmuocoqom mo.m “umou mmo ute_n Lea ammo om mo cowuuzpoLa a ossmmo .pcmn Loo aw ovumou cavemen 053mm<~ Ammo—V Lucoz EOLm pouamvu mEou_ uncu— MNM. m~_. Nae.mm omwm_~._~w oo.ooe oo.oom.~_ oe.e_m.m m a... . _.mmm w nmm.mo_ oem. mm_. amm.~m om.w_~._~m oo.ooe oo.oom.~. oo.m_m.w m cm.” . _.mom m nmm.mc_ museum; xu_co Loo umoo .mHOF voguHm; xo_co Loo umOu mmm vacuum; mxo_zo o_no_mm consaz mumou .oHOP Amo_cu m. x oo.m~mv >Lo>__oo mmc_umcoao >LoLUHm: umoo mam momcoaxm mmmo coNOp Loo ounce pom coNOp consaz pom mmmu consaz N Axmmv m>mo a.-. Axoov “sea a.-. u a < m o h m E0 _ a. umou xu_;u ucmmmoca co >u___nmzoum; mo muoommo och .m 0.26» 28 Effects of Storage on Stage of Embryonic Mortality The second area under investigation was to link storage to the mortality of the pheasant embryo either prior to or during the incu- bation phase. Embryonic mortality may be due to any abnormal condition within the egg or its environment. Prolonged storage has been indicted as a key factor in the failure of the egg to commence incubation (Romanoff, 1938). Another factor to be considered was the relationship of storage and mortality in the latter stages of incubation. It was necessary to eliminate two of the ten hatches due to the inability to collect sufficient data. The treatment required the eight remaining hatches to be segmented with regard to mortality as follows: 1. Infertility or very early dead 2. Stage I of development 3. Stage 2 of development A. Stage 3 of deve10pment Figures 2 through 7 illustrate the various stages. The eggs classified as infertile showed little or no distinct deve10pment, and due to their inability to incubate, they were not statistically analyzed (Table 10). The three critical stages were analyzed using the chi-square method (Mendenhall, 1971) to determine whether storage had any effect on embryonic mortality. Only two hatches (the second and the fifth) were found to be significant; therefore, it is concluded that the data do not present sufficient evidence to inculpate storage as a major link in various stages of embryonic mortality. Further evidence was demonstrated by chi-square analysis encom- passing all eight hatches (Tables 11 through 18). Table 19 corrobo- rates the results proven by inSpection of individual hatches. The comumnauc_ mo m>ov am Loumo co_uoc_meo u_ooumoLumz« 29 .m.n_ mNN mm~_ _ mm.m_ mmu _:m_ N mmw_ NmN «mm. m mm.m_ mmm mmm. : m~.o~ 0mm Ram. m mo.m_ ~m~ me. m ~m.o~ 00m .43. n mn.m_ Now mm:_ m :99 EN 3.: m .m._~ m_m mm:_ o— mm._~ m_m mmq— __ 0:.mm ::m on:. N— mo.m~ 0mm o_m_ m— am.m~ no: mmmp :— o__ucomc_ o__ucomc_ “om mmmu ommcoum c_ m>mo acmocom wo consaz mo topazz «vo_coa _m_cu mc_cap ammo o—_ucomc_ mo omwucoucom .o. o_nmh m.m>.mcm economu.;o mc.m: >u...nmn0ca mo .o>o. .o. um ucmo.m.cm.m« «8.8... .wé ...m m am... 2 m9: 2 _ N 0:. m 2.2 : 2.2 a... N ...m m om... m. mm.m. m. m mm.m m m:.N. w. mn.m. o. J mm... m. mN.o. _. Nm.m~ aN m EN. 8 8.2 m. 3.3 3 m w mm.m. N. wm.m. NN mm.mN NN N .W m. 8.2 N 3;: m. 8.2 N... m m... mm.m. 0N mm.m. m. mm.mN 0N m .W NN.N. N. 0:.N. o. .m.mN mN 0. a .~.N. m mo.m. w. mN.NN RN .. :n.o. o MN.m. MN No.MN ON N. #5.0. .. MN.m. m. No.MN MN m. N.... m. mw.m. ON mm.mN m. 4. touuoaxm po>comno touuoexu vo>comno vouooexw po>comno ucosuooch m>mo :Nim. «>6: N.am m>mo wt. Nfi gone: c. gamut mo ommum co ommLOum mo ouco:.mc. och ... o.nmh 31 m.m>.mcm economi.;o mc.m: >u...nmnoLo mo .o>o. mo. um ucmu.m.cm.m uozx «SEN Nx mm.m m min m mad m . wm.m o. mm.m 5 Nu... N. N +3.0. :. mm.m. N. Rd. m. m mad o. mN.m. o. 053 m. a a... .2 mm... m ii. m. m 4:.0. N. mm.m. .. mm.m. w. 0 mm 3.3 m. 8;: i an: S N H mm... .. No6. m. mad. MN m m mmé : 2.9 2 Sum. N. m m mm... m 3... N. i.m. N. o. a mod N 3.2 N. 3.2 m. : m..m m :m.m .. .m... .. N. 9.2 N 3.2 2 2.2 .... m. mm... N. No.m. .N mm.w. :. :. vouoooxw oo>comno vouooaxm co>cmmno vouooaxm vm>comno ucoeumuch msmo a~-w. msao N_-m msao w-— m% Loam; c. sumac mo ammum co ommeoum mo cocoa—me. och .N. o.nmh 32 m.m>.mcm ccmaomu.;u mc.m: >u...amn0ca No .o>o. mo. um ucmo.m.cm.m uozm «2.3 u Nx mNN m 8.2 N 3.2 S _ Nm.m m mm.m : mo.ON 0N N No.4 m o..w m .m.N. N. m m:.N w m.... N. 0:.MN NN J m:.N m m.... c. 0:.MN NN m m..m N 0N.N m o..m. m. m Mw S... m 86 o. 8.2 o. N m 8A N 9.... m. 3.: N. m m... Nm.m N w:.N. m m..mN .m m We. Nw.w m .o.m. o. om.NN :m o. a N:.: m mm.w m mm.m. m. .. NN.¢ N 00.0. N. N...N m. N. 36 6 mod : em... N. m. Nod .. mod .. ...mé. N. ... vouuoaxm vo>comno touuoaxN vo>comno vouuoaxm po>comno acoeumoch m>mo :Num. m>me N.um m>mo mu. :% zone; c. suave mo omega :0 omocoum mo ouco:.mc. och .m. o.nm# 33 m.m>.mcm a.maomu.;o mc.m: Nu...nmnoca mo .o>o. .0. am acmu.w.cm.m# «mN.e. u «x Nm.N : Na.~ m ma.m. N. . ...m. 0. Nm.m N 00.:N 0N N .w.N. m m0.m m m.mN mN m m:.m m m..: . m.N. mN 4 ..0 0 .N.N . N... m. m N0.N N. mm.m . 0...: N. 0 m... .o.N w ...m N 92 N. N m N0.N .. mm.m . 0.... m. w m am... m N? N Na. ... m m. ...N N. .2 m ...... a o. a wN... m. .0.m m N.0N 0. .. :m.m .. mN.m m N.m. N. N. ...m. m. .m.m : 00.:N :N m. N.N. 0. .#.m 0 :.NN :N 4. vouuonxu vo>comn0 vouuoaxu vo>comao pouuoaxu vo>comn0 ucoeumoch mNma :N-m. .Nma N.-m .Nmo m-. mk noun; c. gamut mo woman :0 omMLOHm mo ouco:.mc. 05k .J. 0.0mh 3A m.m>.mcm economu.;u 0c.m: >u...0mnoca mo .o>o. 00. um ucmu.w.cm.m uozs «mm.MN x 00.0 m m..0 : :N.m m . Nm.0 N 0:.0 N mm.m m N mm.m .. 00.0 m Nm.N 0 m 0N.N 0 N..N N ...0 0 a 00.0 .. 0N.0 N 00.0 0 m NN.0. .. 0m.m N m..0 0. 0 W 00.0 m NN.m m. 00.N m N .w ON.N o. N..N 0 ...0 m 0 mm NN.0. 0 00.:. m. mm.N. m. m .M Nm.m. m. :0.N. m. 0N.0. m 0. a .N.0. 0. N:.N. 0. 00.:. N. .. :N.NN NN 0...N 0N 00.0. oN N. J:.m. ON ...0. m. ::.m. ON 0. m~.N.. m. 0o.0. w. m0.m. o. a. vouuooxm uo>comno vouuoaxu vo>com00 vouooqu no>cum00 acoeuooch “Nae a~-m. a.ma N.-m .Nma 0-. 0% guum; c. gumov mo woman no «mucoum No ouco:..c. och. .m. c.0mh 3S m.m>.mcm ocmavmi.;o mc_m: >0...0maoca 0o .o>o. mo. um acmo.m.cm.m 002* «m0.Nm u Nx NN.N o. 00.0 N 0m.m o. . :N.0 m 00.: N 00.0 0 N m..m 0 00.0 M. Na... N m m..m m. 00.0 a N0... .. a :N.0 m 00.: 0 mo.0. 0 m 0a.N. N. mm.m 0 0..0. m. 0 m. 0:... N. o0.0 .. 00.4. N. N .m m0.o. o. o..0 0 m0.:. N. 0 mm 0a.N. m. mm.m 0 0..0. m. m .m 8.2 N 2.0 : 8.... m. o. a m0.m .. Nm.N N NN.N. N. .. .0.N. m 00.0 .. o0.0. m. N. m..m m 00.0 N No... 0. m. 00.0 : 0..m N am.0 o. :. touuoqxw 00>Lomno touuooxm 00>Lomno vuuuooxu 00>Lomno ucoeumock m>mo :Nu0. msma N.-N m>ma 0n. Nk Loam; c. sumac mo omMNm co ommLOum No ouco:.wc. ask .0. 0.0mk 36 m.m>.mcm ocmzvmu.:u 0c.m: >0...0maoca mo .o>o. 00. um “coo...c0.m uozk emm.:N n x 00.0 m 0m.m 0 no.0 m . om.N 0 N0.: 0 N0.0 0 N NN.0 m :0.m m 00.0 N m 00.: : mm.m : N0.: 0 : 0m.m : 00.m m 00.0 N m :0.0 o. 00.0 N 0N.0 0 0 m. mm.0 0 00.: . 0..0 N N .W NN..... +1 0.0.0 N. 0N.0. .. 0 Wu: mm... m. 00.N 0 NN.0. 0 0 m .0... m. :0.N 0 m.... 0. 0. .a NN.:. 0 0:.0 0 0N.m. 0N .. mm... N. 00.N 0 NN.0. N N. 0N.0. m. .m.0. 0. MN.:. 0. m. 00.:. m. :N.0 0 00.0. 0. :. touuoaxu vo>L0mao vauuoaxu vo>LOmno vauooaxm vo>comno acosuaoch mNmo :Nu0. m>mo N.u0 m>mo 0n. 0% Luau; :. cuoov 00 «mean so ommcon mo ou:o=.mc. och .N. 0.00h 37 m.m>.oco ocmaomu.co 0c.m: Nu...cmcoLq mo .o>o. mo. 00 acou.u.:0.m 002% emm.0N u Nx mN.. N 0... o 0o.N m . NON. o 0:. . m0. . N .m.m m Nm.N . N..: : m 00.N m 00.N m 00.: m : Nm.0 : 0..: 0 m.N 0 m .0.m 0 NN.m m N0.0 m 0 ”w NNN m EN 0 N... : N m N00 N N:.: N NmN o. 0 m .o.N N 00.: : 00.0 0 0 .m 00.0 : 00.N N 00.N .. o. a N0.0 m .:.: : N0.N 0 .. .m.0 o. 0..: N m.N 0 N. N:.m 0 0N.0 0 mN... m. m. N0.o. 0 oN.N .. .0.N. :. :. vouuonxm vo>comco bouuoaxm no>eomco vouuoaxu 0o>comco ucosuooch m>oo :Ni0. mNoo N.u0 «>00 0:. 0% cuumc c. canon 00 omoum co omocoum mo ouco:.mc. och .0. o.coh 38 m.m>.ocm ocoaomn.cu 0c.m: >0...cmcoLQ No .o>o. 00. um acoo...c0.m 002* ....N0m.Nm u N.. ..0: .: ..N: 0: 0.00 ON . :.00 m0 N.:0 :: 0M.MN 00 N :..0 00 N.00 :0 :..0 MN M 0.00 00 0.00 N0 .NN 0N : 0.N0 00 :..0 N0 .m0 00 0 0.00 00 N.00 00 N.N0 N0 0 0.0N m0 :.:N 00 0.00. 00 N ...N 00 N.00 00 N.:0 00 0 0.00 N0 ..:0 N0 0.M.. 0.. 0 0.N0 0N N..0 0N 0.00. N.. 0. 00..0 0N No.00 00 M.00. 0.. .. 0..00 00 M.00 00 0.0.. :.. N. 0.00 00 0.00 :0 N.0M. N:. M. :.M0 00 0..0 M0. 0.MN. 0.. :. vouquXN 0o>comco wouooaxm 0o>comco wouooaxm vo>comco ommLOHm M omoum N omoum . ommum c. m>00 00.Loa couoc uc0.o 0c.c:0 >0..oucos u.co>cch 0o.ooa mo m.m>.mcm ocoaomu.c0 .0. o.cmh 39 null hypothesis of independence of storage time and stage of death indicates that the data to not present sufficient evidence to indicate that the length of storage was directly linked to stage of death. Table 20 establishes the fact that the first stage of death had over A0% of the total embryonic mortality. When subjected to an analysis of variance, a significant difference was computed (Table 21). To pinpoint the difference, orthogonal contrasts were applied. Table 22 indicates a significant difference between stage 1 and stages 2 and 3 (combined), but no difference was detected between stages 2 and 3. Embryonic mortality during stages 2 and 3 may be due to other ex- ternal factors (hereditary and management) or to internal environmental factors such as temperature, humidity, and/or air movement in the incu- bator. This is in agreement with Sitman and Ablanalp et al., (1971) who investigated the effect of extended storage on quail, chicken, and turkey eggs. A0 N0.0N :.0N N.0: ommco>< 0%: E: 31.0% .33 0.0N N.0M 0.:: . 0.0N 0.:N 0.0: N 0.N0 0..M 0.0M M N.0M 0.0N 0.0m : 0..m ..0N 0.N: 0 N.0M 0.0N N.0M 0 ..mm 0..m 00.0m N :0.:m ..0N 0.NM 0 0.0m 0.0M N.00 0 :.0N 0.0N N.N: o. 0.0N 0..M 0.N: .. 0.0N N.Nm N.0M N. N0w0N 0.0N 00.0: M. N..0N 0.0M 0.NM :. mxmo :Nu0. mNoo N.u0 m>o0 0-0.30: :N ommcoum c. m>m0 ommLONm mo m>o0 0cm omoum >0 wouuowmo >0..~ucos u.co>Lch mo omoucoocom .0N o.coh A1 Table 21. Analysis of variance for data in Table 20 Degrees of Sum of Mean Source Freedom Squares Square F-Value Treatment 2 1061.32 1061.3 37.91* Error 39 1091.2A 27.98 *Significant at Pxfi.01 mmacf. 83: 3.3. an EBEé: o2»? #2 mm: .9 L .m> a .~> u «a m>mu :mum. m ommum muoo. . mamgw> mzmgu> mu u m _1_no u .u m>mv ~_1m N ommum ~u um: No L Ans + ~>V1 _>~ u .o msau :~-m_ .m.~m » m>au 5.1m m a N r _o n u _1_1~ n .u mzmeo> mamuo> .U N m>mv muo _ ommum mo:_m>au mco_um_:u_mu oucotcoaovc_ unmeucou $0 ummuucoU mc0m_emasou o:_m>uu LOm away On m_mu0u co_uq_gumoo .chmOsuLo acoEumoLu mo acomu_mmoou ozu Lo; mumuk .N o_nmh scum vo>_eov oucm_gm> mo m_m>_aco scum anagucou _mcomosugo .NN o_nmh 43 Figure 2 Stage l 6 days: Pigmented region of eyes about 2 millimeters in diameter; limb buds appearing as distinct projections from body; cerebral hemiSpheres (forebrain) and midbrain lobes very prominent. Figure 3 Stage l 7 days: Pigmented region of eyes about A millimeters in diameter; limb buds showing no visible digitation; midbrain lobes still prominent; Upper mandible appearing as a slight protuberance. Figure h 4h Stage 2 lh-IS days: Figure 5 Embryo appearing on its left side. Pipping tooth should be fairly discernible. Feathering on the top of the head, auditory openings and upper margins of the eyes. Scales on legs and feet barely visible. Stage 2 l6-l7 days: Embryo shown in circular position. notice total separation of toes but no webbing. Feathering is increased to cover entire head (around eyes) but not fully developed. Aper- tures of eyes are assuming proportions near normal for newly hatched chick. Chick also has begun its rotation to the long axis of the egg. Scales on feet and legs are readily discernible. 45 Figure 6 Stage 3 l8 days: Feathering on the embryo is well advanced. Eyelids closed, eyes now appearing normal in relation to head of chick; development of webbing between toes evident. Right foot touching head and left foot touching lateral aSpect of head. Right wing starting to press over head; head commencing to rotate to the right. Figure 7 Stage 3 2h days: Pipping of shell partially completed. However, it is observed that the embryo failed in freeing himself and eventually succumbed to exertion and finally expired. CONCLUSIONS From this research, the following becomes apparent: l. Prolonged storage does play a significant role in the hatch- ability of ringneck pheasant eggs. Ten days approaches the maximum limit before setting eggs. 2. The influence of storage on embryonic mortality is more prevalent in the initial critical period than the other two stages. 3. The l-lO day storage results in lower cost per chick and a greater number of chicks; therefore, increased income. #6 LITERATURE CITED LITERATURE CITED Asmundson, V. S., and Mclleath, I939. Some factors affecting hatch- ability of eggs. Poultry Sci. l8: I56. Becker, W. A., I960. The storage of hatching eggs and the post hatch- ing body weights of chickens. Poultry Sci. 39: 588-590. Becker, W. A., and C. E. Bearse, I958. Pre-incubation, warming, and hatchability of chicken eggs. Poultry Sci. 37: 8hh-9h8. Becker, w. A., J. V. Spencer, and J. L. Swartwood, I964. The pre- incubation storage of turkey eggs in a closed environment. Poultry Sci. #3: 1526-153“. Bernier, as quoted by Landauer, l95l. Micromelia VII, overdominant recessive lethal in the domestic foul. Records of Genetic Soc. of Am. 66. Boca, as quoted by Lippencott, I933. The effect of age and holding temperature on hatch of turkey and chicken eggs. Am. Sci. #9. Bowman, J. C., I966. Storage of hatching eggs. Br. Poultry Sci. 7: 2l9-225. Carter and Freeman, I969. The fertility and hatchability of the hen's egg. Br. Egg Markt. Board. Dunnett, C. W., l96h. Biometrics 20: k82-h9l. Edwards, C L., I902. The physiological zero and the index of deve10p- ment for the egg for domestic fowl. Am. J. of Physi. 6: 35l-397. Farnsworth, G. H., and D. C. Warren, I962. Effect of age and turning on hatchability of eggs. Poultry Sci. hi: I6h2-I6h3. Funk, E. H., I939. Factors influencing hatchability in the domestic fowl. Mo. Agr. Exp. Sta. Bull. 3AI. Funk, E. N.. and H. V. Bellier, I9hh. The minimum temperature for embryonic development in the domestic fowl. Poultry Sci. 23: 538-590. Funk, E. N.. and J. Forward, I95I. Effect of humidity and turning of eggs before incubation on hatching results. No. Agr. Exp. Sta. Bull. 559. “7 #8 Gordon, C. 0., and H. S. Siegel, l966. Storage of pedigreed hatching eggs in Cryovac. Poultry Sci. #5: l369-l37l. Gowe, R. 5., l965. 0n the hatchability of chicken eggs stored in plastic bags flushed with nitrogen gas. Poultry Sci. Ah: h92-h95. Henderson, L., l9h2. Hatching ability of poultry part III. Mich. Agr. Exp. Sta. Qtr. Bull. 25: l5I-I56. Kaufman, as reported by Landauer, I967. The hatchability of chicken eggs as influence by environment and heredity. S3. Kosin, I. L., I956. Studies on pre-incubation warming of chicken and turkey eggs. Poultry Sci. 35: I38h-I392. Kosin, I. L., and T. Konishl, l973. Pre-incubation storage conditions and their effect on the subsequent livability of chicken embryos: exogenous C02, plastic bags, and extended holding periods as factors. Poultry Sci. 52: 296-30l. Labisky, R. F., and J. F. Opsahl, I958. A guide to aging of pheasant embryos. Nat. Hist. Survey Div., State of III. Biolo. Notes, 39. Landauer, N.. I967. The hatchability of chicken eggs as influenced by environment and heredity. p. 50. McConachie, J. D., F. N. Jerome, and W. F. Pepper, I960. The effect of pre-incubation treatments on the hatchability of chicken eggs. Poultry Sci. 39: 886-889. Mendenhall, W., l97I. Introduction to Probability and Statistics. 3rd ed., Duxbury Press, Belmont, Calif., p 2h0. North, M. 0., I972. Commercial Chicken Production Manual. pp 8l-I00. Olson, N. W., and S. K. Haynes, I998. The effect of different holding temperatures on the hatchability of hen's eggs. Poultry Sci. 27: #20-926. Proudfoot, F. 0., I965. The effect of film permeability and concen- tration of nitrogen, oxygen and helium gases on hatching eggs stored in polyethylene and Cryovac bags. Poultry Sci. Ah: 636-6hh. I96h. The effect of plastic packaging and other treatments on hatching eggs. Can. Jr. Animal Sci. Ah: 87-95. I966. The use of sealed Cryovac and polyethylene case liners with and without nitrogen gas for the preservation of hatching eggs. Poultry Sci. #5: l05-l08. Public Acts of l97l Section 26 Act l33. Pheasant Stocking Proposal: 3 Rezzler, Poultry Digest. March I97h: l27. ‘19 Rolf and Sokol, I969. Statistical Tables. Romanoff, A. L., l93h-l938. Studygof Artificial Incubation of Game Birds. Cornell Univ. Agr. Exp. Sta.: I0. Romanoff, A. L., and A. J. Romanoff, I9h9. The Avian Egg. Wiley: New York. Sadler, W. W., I95h. Incubation factors affecting hatchability of poultry eggs. Poultry Sci. 33: 33. Sittman, K., H. Ablanalp, and C. F. Meyrdick, l97l. Extended storage of quail, chicken, and turkey eggs. Poultry Sci. 50: 687. Snedecor, G. W., and W. G. Cochran, I968. Statistical Methods. 6th ed., Iowa State Univ. Press, Ames, Iowa. Spencer, J. V.. J. L. Swartwood, and W. A. Becker, I968. Controlled atmOSphere storage of chicken hatching eggs. Poultry Sci. A8: Abstract. Warren, 0. C., H. A. Roff, and E. Long, I965. Hatchability of eggs stored in plastic lined egg cases. Poultry Sci. Ah: l278-1280. Woodard, A. E., and A. Morzenti, I975. Effect of turning and age of egg on hatchability in the pheasant, chuckar, and Japanese quail. Poultry Sci. 5h: l708-l7l0. Mill‘il'lllllllllills