THE EFFECT OF VAREQUYS TYPES MD {NTENSST‘QE Q? ELEC‘E‘MC LEGHW QM THE EGG ?’EG*§UCTE©N Q? FULLE‘EE anti THE EFFECT Q? LEGHT RATIONBNG OR THE EGG} FRC‘EBUCTZQN 0F F’ULLETS- Tim“: {‘M flu: Emma GE M . 5-. MK'CHEGAN STATE UN’WEESITY Charles Evans Ostrander 1960 TH 3551: l. . JI“ U L I B R A R Y Michigan State University _ ._.—-J “— THE EFFECT OF VARIOUS TYPES AND INTENSITIES OF ELECTRIC LIGHTS ON THE EGG PRODUCTION OF PULLETS and THE EFFECT OF LIGHT RATIONING ON THE EGG PRODUCTION OF PULLETS By Charles Evans Ostrander AN ABSTRACT Submitted to the College of Agriculture Michigan State University of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE DEPARTMENT OF POULTRY SCIENCE 1960 Approved ’ W ABSTRACT Poultry lighting has been used to stimulate egg pro- duction since late in the nineteenth century. Dr. E. C. Waldorf of Buffalo, New York, did some of the first record- ed research on stimulation of egg production by use of artificial light. For many years the standard recommendation has been to provide a 13 - 14 hour day, using a 40 watt bulb in a 16 inch reflector, suspended six to seven feet above the floor, for each 200 square feet of floor area. During the past few years some claims have been made that egg production could be increased by increasing the light intensity visible to the human eye or by using various newer types of luminaries. It has been thought by many poultrymen and others in the poultry field, that egg production was increased when lights were turned on during dark days. A more recent recommendation to increase egg pro- duction has been to restrict the light during the growing period and then increase the length of day by gradually in- creasing the lighting period throughout the laying period. When careful observation appeared not to substantiate some of these claims, it was decided to test them under care- fully controlled conditions. These tests were conducted 2 over a period of three years - 1957-58, 1958-59 and 1959-60. Four different types of luminaries were tested, including the R-BO, a 75 watt conical type reflectorized incandescent bulb; the "Birdseye 60," a 60 watt incandescent bulb re- flectorized in the upper half; a 40 watt fluorescent light and the conventional 40 watt bulb in a 16 inch reflector. Each test was replicated and it was found that production differences were not significant when tested by the "t" test or the coefficient of variance. No one type appeared to produce more eggs than the other when a 13% hour light period was supplied. The effect of various intensities of light on egg pro- duction was also tested. Four variations, including the regular 60 watt incandescent bulbs, 40 watt fluorescent lights, 100 watt incandescent bulbs and 15 watt red bulbs‘, were tested. Again, no significant effect on egg pro- duction was shown by any of the treatments. From this work, it appears that a 40 or 60 watt incandescent bulb for each 200 square feet of floor area is sufficient for maximum egg production. The 15 watt red bulbs give sufficient red rays for maximum stimulation if suspended 18 inches over the heads of the birds on the roosts. Turning lights on during dark days was tested by mounting photoaflectric cells in the pens to turn on the lights whenever the intensity drOpped below a certain point. 1Suspended 18 inches over the birds' heads on the roosts. While this technique gave a slight increase in egg pro- duction, it was not significant when checked by the pre- viously mentioned tests. The increase did not appear to Justify the purchase of the photo-electric cell or the cost of the extra electricity used. The photo-electric cell increased egg production 1.3 eggs per bird above the con- trols over a six months period. At three cents per egg this gives an increase of 3.9 cents per bird. The extra cost for electricity, at 2¢ per kilowatt, used during dark days was 3.7 cents per bird leaving a balance in favor of the photo-electric cell of .2 cent per bird per year not figuring the cost of the photo-electric cell or installa- tion. When checking the use of rationed light, starting at six hours per day and increasing 15 minutes per week, it was found that the controls produced 13 more eggs per bird than the light rationed birds. The controls were given a 14 hour day throughout the laying year. When checked by the "t" test and the coefficient of variance,there was found to be no significant difference. Observations from the tests were that: 1. There was no difference in production from any of the various types of luminaries used. 2. a) .There was no benefit from using in- tensities higher than those produced by a 40 watt bulb in a 16 inch reflector. b) Egg production was Just as satisfactory when 15_watt red bulbs were placed 18 inches over the birds' heads as from any other treatment used. 3. Rationing light during the growing period and laying period had no beneficial effect on egg production. From these observations it was concluded that the standard recommendation, using a 40 watt bulb in a 16 inch zéeflector, or its equivalent, for each 200 square feet of ifiloor space is as satisfactory as any other type or system c>f lighting tested. THE EFFECT OF VARIOUS TYPES AND INTENSITIES OF ELECTRIC LIGHTS ON THE EGG PRODUCTION OF PULLETS and THE EFFECT OF LIGHT RATIONING ON THE EGG PRODUCTION OF PULLETS by CHARLES EVANS OSTRANDER A THESIS Submitted to the College of Agriculture Michigan State University of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE DEPARTMENT OF POULTRY SCIENCE YEAR 1960 ACKNOWLEDGEMENTS The author wishes to express his sincere appreciation to Professor C. N. Turner of the Agricultural Engineering Department at Cornell University who has worked very closely ‘with him on this research project and to Dr. J. H. Bruckner, Iiead of the Poultry Department at Cornell University, for Iaroviding the facilities for the tests and his guidance, amivice and encouragement during the time the work was carried on. He is also indebted to Dr. H. C. Zindel, Head; IDI~. R. K. Ringer; and Dr. T. H. Coleman of the Poultry Ek31ence Department, Michigan State University, for their ccxntinued advice and guidance during the preparation of this thesis. Grateful acknowledgement is due Dr. w. D. Eaten, .Agricultural Statistician, for his help in analyzing the 'results statistically, Mrs. Carol Hall for her clerical help, J. B. Ward for the photographic work and E. H. Farmer for his assistance in arrangements. Above all, the author is indebted to his wife Gracia for her constant interest and encouragement and for her assistance in the preparation of this thesis. Finally, the author is grateful to his two daughters Linda and Marcia for their understanding and patience during the preparation of this thesis. II III IV VI VII ‘VIII IX XI TABLE OF CONTENTS Page INTRODUCTION 1 REVIE‘iv OF LITERATURE0.0.0.000...OOOOOOOOOOOOOOCO 4 OBJECTIVESOOOOOOOOOOOOOOOOOOOOO00.0.00000000000020 GELQERAL PROCEDLIREO0.0.0.0000000COOO0.0.00.00000021 TEST ICO...00.0.0000...OOOOOOOOOOOOOOOOOOOOO0.0.21 TEST II.........................................36 TEST III........................................45 TEST Iv.........................................50 TEST V..........................................56 SUMMARY.........................................7O BIBLIOGRAPHYOOOOOOOOOOOOO0.0.00.000.00.000.0000073 TABLE II III IV VI VII VIII IX LIST OF TABLES Page AREA OF PENS, NUMBER OF BIRDS, EQUIPMENT USED AND LIGHT TREATMENT FOR TEST I..................23 EFFECT OF VARIOUS LUMINARIES ON PERCENTAGE EGG PRODUCTIOEQ BY MONTHOOOOOOOO0.0.00.0000000000000029 EFFECT OF VARIOUS LUMINARIES ON NUMBER OF EGGS PER BIRD0....OOOOOOOOOOOOOCOOOCOO00.0.000000000030 INTENSITY OF LIGHT AND ITS EFFECT ON EGGS PER BIRD BY FOUR WEEK PERIODSOOOOOOOOOOOOCOOOOOOOOO.40 INTENSITY OF LIGHT AND ITS EFFECT ON FEED EFFICIENCY BY FOUR WEEK PERIODS .000000000000000042 THE EFFECT OF USING A PHOTO-ELECTRIC CELL ON EGG PRODUCTION AND FEED EFFICIENCY. . . . . . . . . . . . . . .47 THE EFFECT OF USING A PHOTO-ELECTRIC CELL ON PERCENTAGE EGG PRODUCTION BY WEEK ...............52 THE EFFECT OF USING A PHOTO-ELECTRIC CELL ON EGGS PER BIRD BY FOUR WEEK PERIODS ..............53 DISTRIBUTION OF CHICKS AT TEN WEEKS OF AGE USED IN LIGHT RATIONING TEST AND DEGREE OF RATIONING FROM 10-21 WEEKS OF AGE 0.000000000000057 I-H F“: TABLE XI XII LXIII PAGE EFFECT OF LIGHT RATION FROM 10-21 WEEKS OF AGE ON 21 WEEK BODY WEIGHTS AND ON TOTAL FEED CONSUMPTION DURING THIS PERIOD..............59 SUMMARIZED RESULTS OF RATIONED LIGHT TEST.-...-..64 EFFECT OF RATIONED LIGHT ON PERCENTAGE EGG PRODUCTION BY MONTH 000.000.000.000...00000000000066 EFFECT OF RATIONED LIGHT ON EGGS PRODUCED PER BIRD BY MONTH0......OOOOOOOOOOOOOOOO0.0.0.0006? 'u‘;.‘h-'fi.‘q:‘.._ . . ~.‘r Irv-5.. ’I'TFTfi" FIGURE II III IV VI VII VIII IX LIST OF FIGURES PAGE PEN LAYOUT AND LIGHT TREATMENTS USED IN TESTI00.0.00...OOOOOOOOOOOOOOO00.0.000000000000022 LIGHT INTENSITIES FROM LUMINARIES USED IN TEST IO...I...0.0.00.0....00...00.0.000000000000026 VARIOUS TYPES OF LUMINARIES USED IN TEST 1......27 PERCENTAGE EGG PRODUCTION FROM BIRDS WITH VARIOUS TYPES OF LUMINARIES.....................31 EFFECT OF VARIOUS LUMINARIES ON FEED EFFICIENCYO...OOOOOOOOOOOOOOOOO0.00.0.000000000032 EXPERIMENTAL DESIGN OF PENS FOR TEST II SHOWING LIGHT INTENSITIES USED..................38 'EPPECT OF VARIOUS LIGHT INTENSITIES ON PERCENTAGE EGG PRODUCTION BY WEEK...............41 EFFECT OF VARIOUS LIGHT INTENSITIES ON FEED EFFICIENCY BY FOUR WEEK PERIODS............43 MONTHLY PERCENTAGE EGG PRODUCTION FROM BIRDS IN PENS WITH AND WITHOUT A PHOTO- ELECTRIC CELL00......0.000....00......000000000048 FIGURE X XI XII )(III 11 PAGE WEEKLY PERCENTAGE EGG PRODUCTION FROM BIRDS WITH AND WITHOUT A PHOTO-ELECTRIC CELL ...........54 EXPERIMENTAL DESIGN OF PENS USED FOR REARING BIRDS FROM 10—21 WEEKS OF AGE FOR TEST v SHOWING LIGHT INTENSITY AT VARIOUS LOCATIONS WITHIN THE TWO WINDOWLESS ARTIFICIALLY LIGHTED pENs .....................................60 EXPERIMENTAL DESIGN OF PENS USED DURING THE LAYING PERIOD FOR TEST V SHOWING LIGHT INTENSITY AT VARIOUS LOCATIONS WITHIN THE WINDOWLESS, ARTIFICIALLY LIGHTED PENS.............61 EFFECT OF RATIONED LIGHT ON PERCENTAGE EGG PRODUCTION BY MONTH...00.000000000000000...000000068 INTRODUCTION The first recorded investigation of providing ar- tificial light for poultry flocks in the United States was conducted late in the nineteenth century. From this work ‘by Dr. E. C. Waldorf (1889) it was concluded that ar- ‘tificial light increased egg production and the increase ceune about because of the increased feeding period. Early 111 the twentieth century, artificial lights in pOultry kuauses became widely used to increase egg production but exren then, no one suspected that the benefit came from siLimulation of the pituitary gland. There have been many claims for various lighting Borstems, types of lights and intensities of lights during tJde past several years. Most of these claims were unfounded 'because they had not been checked and tested scientifically. Iflevertheless, many of the schemes were adopted by poultry- Inen who have used them throughout the years. For many yeara poultrymen have been using all-night lights with little or no knowledge of benefit or harm or proof of more egg pro- duction. Poultrymen have used high intensity lights but have had no proof Of the benefit from this action. Like- Wise, they have been using fluorescent bulbs, even with their high initfial costs, with no assurance of increased egg production. It has been a common practice to turn on .LM._ A .. the lights in poultry pens during dark days and some poultrymen are now using photo-electric cells to do this for them. No one had apparently checked to see if this technique was of any value or if it actually increased egg production as it was claimed. Recently, various lighting systems which were supposed to increase egg production measurably have been promoted in the popular press and by other means. Some poultrymen remodeled their poultry houses to adopt these new systems without ascertaining if the claims were founded. When poultry was a backyard or sideline enterprise, it made little difference what system of lighting was used, as far as cost was concerned. Now that poultry is a major enterprise, where flocks may consist of thousands of birds, lighting is becoming a major cost. It is not uncommon to- day to find electric bills varying from $100 per month to several hundred dollars per month on poultry farms. With figures of this magnitude, it is important that the money spent bring maximum returns. If high intensities will in- crease egg production, the extra cost can then be Justified; but if no benefit is obtained, this practice should be dis- couraged. This is also true of various types of lights and lighting systems. Due to some of the unfounded claims for various lighting schemes, it was decided to test some of the light- ing practices scientifically in order to obtain the facts. Several tests were designed to check various types of 3 lights for poultry houses and various intensities of light to find the effect on egg production. Plans were also made to check the profitability of turning on lights during dark days. Further tests were designed to check systems of lighting, particularly the rationing of light, to see if they had an effect on egg production. These tests were con- ducted over a three year period and consisted of large enough flocks to be of practical significance. Each test was replicated to increase its validity and value. The tests were set up to measure egg production, feed per dozen eggs, mortality and in some instances egg size and cost of operation. REVIEW OF LITERATURE There were a few people who foresaw the benefit from artificial light to increase egg production in poultry even back in the eighteen hundreds. The first recorded work in the United States was done by Dr. E. C. Waldorf in 1889 at Buffalo, New York, as reported by The Reliable Poultry Journal Publishing Company (1920). Dr. Waldorf was a practicing physician and a student of natural sciences. He found that if lights were turned on at uneXpected moments, the chickens were disturbed. He devised an automatic time- trip and patented it as the "Waldorf Chronometric Adjuster”. The light that Dr. Waldorf used was produced from gas. He used four 100 candle power Argand brass burners. These were suspended from the ceiling one foot from the outside edge of the building and five feet from the floor. Each burner was equipped with a reflector that reflected the light down and to the back of the house. The lights were turned on at 3:30 A.M. and off at 7:30 A.M. and then turned on again at 5:00 P.M. and off at 8:00 P.M. allowing a 16% hour day. Dr. Waldorf and other early workers with ar- tificial light thought the benefit therefrom to be the re- sult of increased exercise and increased intake of feed and water. J. P. Jordan (1920) made the following statement. "What if you had to go to bed at half past three or.four o'clock on a winter afternoon, your food all digested by ten or eleven o'clock, and then you had to huddle yourself up as best you could until 7:30 or 8:00 before you could see to eat again? You, too, would become discouraged with life, contract all diseases born of weakness and fail to produce your share of the interests of life which you other- wise produce if you were given the opportunity." Professor James E. Rice (1920) stated that we could- overlight laying hens and cause them to lay so heavily they would break down. He indicated that 12-14 hours of light is best and safe. "If light is provided so hens have more than a 14 hour day, it is dangerous to their well-being.” Professor Rice published elaborate colored graphs in 1918 showing the time of lighting laying hens and the production from various lighting periods. Results from one of the first practical tests in the field were published by the Reliable Poultry Journal Pub- lishing Company in 1920 on a flock of.420 Single Comb White Leghorns at the Hillcrest Farm, Orchard Park, New York. They showed that lighted birds laid at the rate of 51.2 per- cent and the unlighted birds laid at the rate of 17.7 per- cent from January 10 through February 10. J. E. Daugherty (1927) stated that lights should not be used for breeders. He further claimed that it would be of little value to bring the birds off the roosts on cold mornings without food and water. Daugherty indicated that a 100 watt bulb in a commercial reflector gave better re- sults with more intensity than using two 50 watt bulbs in homemade reflectors. Professor R. T. Parkhurst, of England (1930), report- ed that May hatched pullets laid 3% more eggs when lighted than when not lighted. He indicated the most important factor was that the largest production came when eggs were highest in price, thereby increasing total income. Pro- fessor Parkhurst is credited with saying that lighting was "not primarily a method of increasing egg production but changing the season of production to a time when eggs are highest in price." Elizabeth Whetham (1933) reported that the change in ration of light was probably more important than the absolute amount. She indicated that the effect of all-night lights or long periods of light wears off. Back in 1933, Whetham suggested the possibility of stepping up the length of light periods but never repOrted doing it. Whetham suggested that low producers (inherently) received more effect from light than high producers. Whetham also suggested that we may find other spectral rays more effec- tive than those from electric lights. Experimental work in 1941 by Roberts and Carver con- cluded that 13 hours of light satisfies Optimum require- ments for egg production. Egg production is stimulated by the stimulation of the pituitary gland. Sturkie (1954) reporting work by Benoit (1937 and 1950) stated that irradiation of the head and eyes stimulates the pituitary, but when the head and eyes are covered and other parts of the body irradiated, the hypOphysis is not stimulated. When the eyes are enucleated and light is introduced only through the orbit by way of a quartz rod, the pituitary is stimulated. The hypOphysis can also be stimulated by irradiating the head even when the Optic nerves are cut and also by stimulating directly the hypothalamus and hypOphysis with light. Ultraviolet and other ray_: Hughes 23 31. (1925) eXposed hens, on vitamin D deficient diets, to ultraviolet rays and received four times as many eggs in five months from these hens as from the groups of hens not exposed to ultraviolet rays. On the other hand, Mussehl and Yung (1942) exposed hens to ultra- violet rays and obtained the same number of eggs as when conventional fish oils were used in the ration. G. E. Kable and F. E. Fox (1928) of the Oregon State Experiment Station reported that using carbon arc lights, supplemented with a 50 watt incandescent lamp, increased egg production and decreased mortality. The control pen had two 50 watt incandescent lamps. Mortality under the arc lamps was 10.4% and mortality under the control lamps was 26.6% during a five month period. They also reported better shell strength under the arc lights. The cost of electricity for the arc operation was $11.25 and $14.40 for the arc carbons, for a total of $26.65 over a six month period compared to $2.75 for the two 50 watt Mazda lamps. They did not report the production obtained. Barrott, Schoenleber, and Campbell reported in 1951 that light is generally thought of as being radiation which is visible to the human eye (light waves of 4000 - 8000 Angstrom units).1 Below 4000 Angstrom units are the ultra; violet waves which are not visible. These waves kill bacteria, produce sun burn and fluoresce certain material. 1. Bactericidal 2000 - 2800 Angstrom units 2. Erythemal or Suntan 2800 - 3200 Angstrom units 3. Black light 3200 - 3800 Angstrom units Vitamin D is activated by the erythemal band 2 which peaks at 2967 Angstrom units. In a five year test, Barrott £3 21. (1951) expoSed hens to ultraviolet rays and obtained 10% to 19% more eggs than from the controls (not exposed). The controls received no daylight or ultraviolet rays but did receive artificial light consisting of 12 foot candles2 under 40 watt white 1Angstrom unit is a measure of light waves. One Angstrom unit is one ten thousandth of a micron. 2A foot candle, as described by T. E. Hienton, D. E. Wiant and O. A. Brown, in Electricit and A ricultural En ineerin , is "the unit of illuminatIon equal to ilIumina- tion of a surface one square foot in area on which there is a uniformly distributed flux of one lumen, or the illumina- tion produced at a surface all points of which are at a distance of one foot from a uniform point source of one candle.” The new candle is defined as, "one sixteenth of the intensity of one square centimeter of a black body radiator at the temperature of the solidification of plat- inum (2046° Calvin)." fluorescent lights for a 14 hour day (They did not report if this fluorescent light gave any red rays). A 15 watt filament light burned continuously in the pens with the exposed birds. All birds had adequate vitamin D in the ration. Additional vitamin D in ration gave no increase in egg production. Exposure to rays longer than ultraviolet but shorter than visible rays gave no increase in egg pro- duction. They concluded that ultraviolet rays peaking at 2537 Angstrom units gave stimulatory effects on egg pro- duction. Intensity of light: Bissonnette (1931), working with starlings, showed tJaat rate of acceleration of spermatogenic activity in- <2reased with intensity of light to a certain point. He sniowed that 10 watts gave the least activity with an in- <3rease up to 40 watts. He received no increase above 40 ‘watts. 0n the other hand, Whetham (1933) indicated that light ration was more important than intensity. Nichols, Gallenbach and Murphy (1944) showed no difference in pro- churtion with intensity from 0.5 to 38 foot candles. They fouxni some evidence of a very intense light causing more tqmnxble from pick-outs. These men also reported no re- lation between light and egg weight and no relation between liefirt and mortality. Barrott and Pringle (1951) tested the effect of light intensity on growing chicks. They tested intensities from -J- foot candle to 24 foot candles and concluded that any- 10 thing above one foot candle was not necessary for good growth. They reported less growth when 12 - 24 foot candles were used. In their tests they also used white, red, blue and green light and found no differences in growth rate attributable to color of lights. Rider (1938) suggested that rearing chickens in dark- ness did not delay sexual maturity. Tomhave (1954) reported that maturity and production are separate processes and that intensity of light during the growing period had little effect on later production. Dobie gt 31. (1946) tested intensities from 1.0 foot candle to 31.3 foot candles at the feeders and found no increase in production from the use of intensities above 1.0 foot candle. They also found no difference in pro- duction between birds receiving light from ultraviolet, ruby red, and red fluorescent lights. These workers found no increase in production when more than 13 hours of light was provided but they did conclude that at least 13 hours of light was required for optimum egg production. Bissonnette (1933) found that low intensity red light gave just as much stimulation for egg production as high intensity white light. He did not report stimulation from low intensity green or violet light, however. Sunlamps were less effective than incandescent lamps. Skaller §£_§l; found that the threshold of light in- tensity to maintain production is below one foot candle over the feeders. 11 Platt (1953) showed that 15 watt red lights 18 inches over the heads of the birds gave egg production equal to that secured from the use of 40 watt bulbs over the work area and much better than that secured when no lights were 3 over the center of the used. The lights were 4 feet o.c. perches. There was no more than 36 inches from any light to the perch. These pens were lighted from 8 P.M. to mid- night, from 8 P.M. to 4 A.M. and from 6 P.M. to 6 A.M. A fourth group was lighted with 60 watt incandescent lights with one bulb for each 200 square feet, from 3 A.M. to sun- rise. The birds in the control pen received no supple- mentary light. The results obtained by Platt were as follows: WHITE LIGHT 3 A.M.-daylight No Art. RED LIGHT light 4—8 P.M. BEE-4 A.M. GENE-6 A.M. Percent Production September 56.9 64.3 61.9 63.3 62.7 Artificial light started on 10/5 October 61.7 68.3 69.8 74.8 70.5 November 53.2 66.6 72.4 68.8 64.0 December 50.2 63.3 73.3 70.7 57.6 January 39.2 54.5 67.5 57.8 59.5 February 34.3 53.7 64.8 58.3 59.4 AVERAGE £9.2 61.8 68.3 65:4 6573""" Platt concluded that if red light is used, it must be dim for if it is too intense, the birds leave the roost. Then 3On Center (from the center of one to the center of the next one). 12 they are too far from the light source to absorb red rays and no stimulation of the pituitary gland takes place. He also concluded that eight hours of stimulation gave best results. With less than this amount, production decreased and above this there was no benefit. Four hours of red light gave results equivalent to those obtained with a 14 hour day using incandescent light. Jensen and Matson (1957) reported that continuous light on chicks produced chicks with eyeballs 38% larger than those of chicks receiving only 12 hours of light. Lighting chicks and its effect on egg production: Mueller 33 a1. (1951) showed growth to 8 weeks of age was most rapid in chicks exposed to atmospheric conditions outside the hover. Chicks given constant levels of light (12 hours daily) made up the difference in weight by 12 weeks of age. This agreed with results by Clegg and San- ford (1951) who used lights that were on for 6 hours and off for 6 hours, on 12 hours and off 12 hours, and on 2 hours and off 2 hours. The test where 2 hours on and 2 hours off was used gave by far the best growth, with 6 hours on and 6 hours off being next best. They concluded the in- creased growth was from extra feeding periods and not from light stimulation. Barrott and Pringle (1951) observed that 12 hours of light and 12 hours of dark gave 71% of the growth obtained from 1 hour of light and 3 hours of dark. Three hours of light and 3 hours of dark gave 87% of the growth obtained 13 from 1 hour of light and 3 hours of dark. They concluded that the number of feeding periods was important but not the only factor affecting efficiency. Jordan (1920) found that if feeding periods were too close, chicks did not feed fully each period. He concluded that feed periods should be timed so that the crop is emptied between each successive period and the feed period needs to be only long enough for the bird to fill the crOp again. The dark period should not be so long that the chick becomes excessively hungry be- tween feedings. Tomhave (1954) reported that production from birds that had been lighted as chicks did not differ from that of those that had not been lighted. The lighted birds matured more slowly and laid less small eggs. The non-lighted birds produced more eggs below 22 ounces per dozen but did eventually lay eggs of the same size as those produced by the lighted birds. Hutt, Lamoreaux and Goodwin (1955) showed that keep- ing chicks on constant artificial light produced some false layers. They indicated that breaking the light period, by providing only daylight, for one month before maturity pre- vented the false layer condition. Carson, Junnila and Bacon (1958) used a series of red, green, gold and blue fluorescent lights, no lights and 24 hours of 60 watt incandescent plus daylight, on growing chicks to check the effect on egg production. They found no significant difference in mortality due to light type 14 or light period. All night lights, regardless of color, stimulated the birds so treated to such an extent that they reached sexual maturity before those receiving only daylight. There was no difference between the effects from colored lights and incandescent lights as far as egg production was concerned. Twenty watt colored lights were used in all cases except where 40 watt red bulbs were used. The lights were located at the ceiling over the work area. The chicks were started on September 9th. At 10% weeks of age, they were lighted by 60 watt incandescent bulbs until the start of the 15th week. These lights were on 24 hours per day. At the 15th week, they were then put on the various treat- ments and left until March 6th. They were then returned to continuous lighting with 60 watt incandescent bulbs. These workers reported no significant difference in pro- duction after production figures were adjusted for delay in maturity. The conclusion was that there was no adverse or stimulating effect from any of the treatments. Length of light period and effect on egg production: A. H. Sykes (1956) reported that sexual maturity was not affected by absolute length of day but that egg pro- duction was affected by absolute length of day and by changes in length of day. He indicated that the effects from decreasing day length were more serious the later the change occurred in the laying year. Sykes housed birds at 12 weeks of age in pens receiving 6 hours of light per day. From time to time he transferred some of these birds to 15 pens that were receiving only natural light. He also took birds from the pens receiving only natural light and put them in the pens with six hours of light. The birds in natural light produced much better than the birds with six hours of light. The birds which were moved to the longer hours of light (natural) increased in production within two weeks and production was maintained. The birds moved from natural light to the six hour pens dropped in production by the end of the second week. There were also differences in birds as to how they were affected. The birds changed early in the laying period were not affected as much as those moved later in the laying period. The last group moved to six hours of light on August 14 went into a molt. Platt (1955) showed that pullets restricted to 8 hours of light matured more slowly than pullets in natural light, The birds on restricted light were given a 14 hour day at 7 months of age. They increased in production rapidly when lighted, and produced much heavier than the natural lighted birds which were lighted from 2 A.M. to daybreak at 35 weeks of age. The 8 hour treated pullets reached 89.4% production aIter lighting and the controls never went above 72.4%. Egg weight was equal at 40 weeks of age. Hutchinson and Taylor (1957) concluded that a change in light is more vital to egg production than a change in season or a change in temperature. They reared one group of birds on 12 hours of light and one group on 23% hours of light both at a uniform temperature of 64-65°F. Part of 16 group two had light reduced gradually to 12 hours starting two months after maturity. This was carried out over 8 weeks of gradual reduction, until 12 hours of light was reached. It was reported that these birds molted as a re- sult of the light reduction. Temperatures were changed to assimilate the autumn season. The egg production was affected adversely in the pens receiving 24 hours of light, when the temperature was lowered. Byerly (1957) found that changes in temperature affect- ed production as much or more than changes in light. He found that pullets maturing at different times are affected differently by lighting. Byerly suggested there are drastic differences in individuals in their response to minimal length of day and to an increase in length of day. Bastian and Zarrow (1955) showed that light and en- forced wakefulness delayed the ovulation of the first follicle of a clutch. Ragab and Assem (1953) found that increases in tem- perature offset stimulation by increase in light to a point that production decreased. They concluded that control of heat is as important as, or more so than, control of light. Hall (1946) showed that by restricting red rays, pro- duction was inhibited. He checked restricted feeding vs. restricted feeding and lighting vs. a control. To restrict all red rays, he used a Corning H. R. Lantern Blue B glass filter with a 60 watt bulb. The light-restricted birds molted quickly and all at once while the other birds molted 17 over a long period of time. Flash lighting: Nightall (1955) reported that Blount compared 1500 watts of light for 20 seconds, at four hourly intervals, between 3 and 6 A.M. with a treatment of 75 watts for 4 hours. The flash system was uneconomical because of in- stallation costs, even though slightly higher production was obtained. A test at the University of Nottingham School of Agriculture conducted by Nightall (1953-54) checked the pro- duction of birds receiving 40, 60 and 100 watts of light for 20 seconds at 2 A.M., 3:25 A.M. and 4:50 A.M. against the production of a control pen of birds which was unlighted. Nightall concluded that 100 watts was impractical as 60 watts produced the maximum production. Production was re- corded as follows: Control 71.1% 60 watt 78.5% 40 watt 68.9% 100 watt 77.8% Sicer (1956) reported that 1000 watts over the roosts for 30 seconds during the night gave equal results to 60 watts from 4 A.M. to daylight even though the birds didn't leave the roosts. He stated that heavy wiring and fusing was necessary when using high wattage. Other lighting tests: Wilson and Abplanalp (1954) indicated that the minimum amount of light necessary to sustain egg production has not 18 been established. They reported that reducing the hours of light to less than 14 hours reduced production regardless of the method used. In four out of five cases, intermittent light gave better production than continuous light. Home with a high rate of production were less affected by light changes than were low producers. Production under short photo-periods was not prOportionate to the amount of light given. Hens were more susceptible to light changes than pullets. Warren and Scott (1936) found they could change the laying period so that it came at night rather than during the day by darkening the pens during the day and lighting them at night. H. M. Simons, Jr. (1955) reported that a two platoon system could be used for layers. To accomplish this there is one work area with two roosting areas which are smaller. With this system, one group rests while the other is work- ing and laying. He reported an average of 70% production in each group. To get 13 or 14 hours of light the group roosting must be lighted l to 2 hours. Current work with lightinggsystems: Considerable work has been done in the past few years and is being currently carried on with different lighting systems. Professor King (1958) at Alabama has reported on re- sults with "Stimulighting". His results indicated very significant increases in production of birds subjected to 19 this system. Skoglund at New Hampshire is also carrying on similar work, but his results have been less spectacular than King's. Ralston Purina Company and Kimber Farms have also been working with restricted lighting during the growing period. They both showed best production results when chicks were restricted to 6 or 8 hours of light during the growing period and placed on 14 hours of light at maturity. Heisdorf and Nelson have been using a step-down, step-up lighting system. In this program, they start the chicks on long lighting periods and gradually reduce this period to maturity. The light is then increased throughout the . laying period. They reported increased production from this system of lighting. OBJECTIVES The objective of this research was to find the bene- ficial application of artificial lighting for commercial poultry farms. To do this, research was set up in five different categories to check various phases of lighting. TEST I was set up to test the hypothesis that equal egg production will be obtained from birds on commercial poultry farms by using various types of luminaries. TEST II was conducted to test the hypothesis that maximum egg production can be obtained without using high light intensities in the laying pens. The purpose of TEST III and IV was to test the hypothesis that it is not necessary to turn lights on, in the laying pens, during dark days if rec- ommended window areas are provided. TEST V was inaugurated to test the hypothesis that egg production will be increased by providing a short day growing period and gradually increasing the light during the laying period. GENERAL PROCEDURE Each test will be reported in its entirety including procedure, results, and discussion before reporting the next test. This is done due to the different nature of each test. All of the tests were conducted at Cornell University on their research farms or on farms leased for research purposes. Single Comb White Leghorns were used in each test. The tests were conducted during the years of 1957-58, 1958-59 and 1959-60. EXPERIMENTAL TEST I EFFECT OF VARIOUS LUMINARIE ON EGG PRODUCTION Procedure: Test I was carried on during the year 1957-58. This test was conducted in a barn on one of the leased farms (Figure 1). Due to the layout of the pens, it was impossible to have each treatment placed in identical pens. One rep- licate of each treatment was placed in each section with replicates of each other treatment (Table I)(Figure I). Pens I, II, III, V, VI, IIIand Ix were used in this test. All treatments were replicated except treatment VI(The 40 watt bulb in a 16 inch reflector). All pens were divided 22 Single Story E III VI Down ( 40 watt ) 40 watt reflectors IX ”p N S Fluorescent 3'30 2 600 feet2 500 feet A m V Down E W II Fluorescent 3 VIII Up “ 60 watt Birdseye 60 ;‘ "Birdseye 60" 500 feet? COURT YARD 600 feet2 Iv Down (Photo-cell) I so watt 75 watt G E R-3O VII Up 2 40 watt 600 feet 900 feet2 Connecting Passage General layout of Hertel Barn. Only that part of the barn used for this test is shown. This is not to scale but shows the general layout of pens used and pen area and type of luminary used in each pen. Pen Layout and Light Treatments Used in Test I FIGURE I Ind. 23 cps: me on m .m.o see: oo as has umpuam «Hasbahw epr o: uncomopcuOcH upoaooamog spa and: and} on use: 04 pcoomohosam HHoouOHogm see: 04 accomopcuqu see: 0; accomouosam ass: op coo ass -csAHm. .sHessHaw use: ma on m .m.o 3&3 mo waxy > see HHH com . coHesoHHdom + N on m on w on m on mfipooz m hJHddEEpo A mmfl w on m om N on N ow nsoom meaaooz m seHesaaou s mmH m on m om m o: M 0m m on m om spawn gags—om poem WOES no .02 epmoz Hope: momma powwow H sass aoH possesses ssmHH sec com: ocosmHsvm .ncHHm no 909552 «scum Ho «0&4 H mqmdg msH maH 00m mNH maH com cam cam OHN cash so .oz com Com 00m com com 900 000 000 or.“ CG” 5 “0&4 HHH> pee HH com - eoHesoHHdoe * HH see H sod - eoHscoHHdom a .HH aHHHs HH> H> +> >H + HHH *HH .02 com 24 by solid partitions but they were not all of equal size; therefore, the birds of one replicate were put in pens of one size and the other replicate in pens of another size. As this building was not insulated it was felt that each pen should be filled to capacity at three square feet per bird. This, of course, made unequal numbers of birds in the replicates of each setup. All reports are on a per hen or a percentage basis so the slight variation in numbers of birds per pen should not affect the results of the test. On October fourteenth, 1330 Single Comb White Leghorn pullets made up of 1120 surplus Random Sample birds 22 weeks of age plus 210 Cornell strain birds of equal age were ran- domly selected. The birds were divided as shown in Table I. All of the birds were fed a commercial all mash lay- ing ration(l6_percent protein) They were hand fed every morning, and a record kept of the amount of mash fed to each pen. The mash troughs were wooden V type, on legs, about 15 inches from the floor. The caretakers were in- structed not to fill the troughs over one half full in order to prevent wastage. The birds were watered with automatic water fountains located across the house in the front half of the pen. These were protected from freezing by heating cables. Each pen had at least two fountains (Table I). Litter used in the pens consisted of chopped straw which matted badly due to the poor ventilation in the pens. The pens had to be partially cleaned several times during the winter because of dampness and packing. During the coldest 25 part of the winter, the birds were fed five pounds of all mash pellets per 100 birds every afternoon at 3:30 P.M. Oyster shells were available, at all times, in each pen. Ventilation consisted of the flue system using the windows for inlets which proved to be unsatisfactory. The lighting schedule was set to give the birds a 13% hour day. To keep this uniform, the time clocks were set to turn the lights on at 5:30 A.M. and off at 8:00 A.M. They were turned on again at 4 P.M. and off at 7 P.M. The caretakers were instructed to clean all bulbs each week to prevent dust from decreasing the intensity of light from any one fixture. Burned out bulbs were replaced immediatekm The intensity of light was measured in each pen using a General Electric light meter of the type used to measure intensities of city street lights. The intensity was measured directly under the lights and at various points in the pens including the corners and roosts. The in- tensities ranged from less than 0.4 foot candle to 11 foot candles. The highest reading was directly under the light (Figure II). The R-301 (Figure 111) had a very high in- tensity ”hot spot" directly under the lamp and dropped off very sharply, a short distance from the lamp where it closely approached the intensity of a standard 60 watt bulb without a reflector. The fluorescent lamp also produced considerably more intensity directly under the lamp, than 1 G.E. R-30 is a conical type reflectorized lamp. CMHHES FOOT ll. 10... 9L__ 75 W Reflector Flood 8 _ All readings taken on a horizontal plane six feet 7 below center of bulb 6 1 40 W Standard Cool 5__ White Fluorescent (Readings taken at center and ends of tube) 4_ 60 W Birdseye Direct A//’ 3 2A.. 60 W Standard / 1... I l ! l l l l 0 l 2 4 5 6 '7 FEET FROM CENTER Light Intensities From Luminaries Used in Test I FIGURE II 26 27 HHH EDEN H pass 5 some 8533 Ho 35 338s rum? 7: 0mm.) mm_d Mo poommm AHOHHcoov .ioomonceocH upw3 on ...... admonoaosa 3s: on 7.-.- .. A m v 0 gene H .|.nr...l. 338 0 an II I .. //. \\../../. 333 ms ems \ ../ ........... \ \\ / ../ ./ / \\. \ / .. \ Z / /\ \ / / III \\\ rlulllnlr //\\\\ // x / . .. / /... . . u\\ .1]: .._x. a\\ \\x V. \\ /.\ H Emma mm as 0 LA m m 8 uotzanpomg queoxeg Ln ‘0 in O on bu O (D Pounds Feed.per Dozen Eggs 32 TEST I 5.8 5.6 5.4 5.0 4.8 4.5 .\ / .°)./ ___R-30 / '. - - -Birdseye 6O 4-4 . \ / :7 -.-.-.40 Watt Fluorescent 4.2 .§/ :. ......40 Watt Ingggdggient .. .//.- 4.0 '. 3" Effect of Various Luminaries on Feed Efficiency Total light day(daylight+artificia1 light) equals 13.5 hours OL—h—J—A——l————L Oct Nov. Dec. Jan. Feb. Mar. FIGURE V k»! \hl averaged 64 percent egg production and the controls (40 watt incandescent) averaged 63.1 percent egg production. Feed efficiency varied little between treatments (Figure V). Although there was no great difference in egg pro- duction from any of the treatments, birds in the pens with the R-30 luminaries were consistently below the others. Figure IV shows that egg production from birds on all four treatments was extremely close throughout the test. The results were analyzed statistically with the help of Dr. W. D. Baten, Agricultural Statistician, using the "t" test and coefficient of variance test. The results were not statistically significant. Discussion: Many claims have been made by service people and poultrymen that various types of lights in the poultry house increase egg production. This test, using "G.E. R-30", "Birdseye 60", 40 watt fluorescent bulbs and standard 40 watt incandescent bulbs, failed to show any significant difference in egg production from any of the treatments. The pens containing the R-3O bulbs, which was the highest wattage of any type used, had the lowest egg production. In one field test, where this bulb was used, egg production was lower than in the controlled test reported. When the R-3O was used in the field test, the light fixtures were a considerable distance from the roosts. Several times birds were observed on the roosts long after the lights were turn- ed on. It was postulated that the "spot" effect of the 34 light failed to light the roost area sufficiently, thereby not stimulating the birds remaining on the roost. The fluorescent lights have the disadvantage of high installation cost but normally the bulbs have a long life. Contrary to many claims, Operation cost for fluorescent lights is no lower than for other types of lights on a watt for watt basis. It is very important, if fluorescent lights are used, to use a type that produces red rays equal to incandescent lights. The pink bulb produces the largest number of red rays and these red rays are the ones shown to stimulate the pituitary gland in chickens thus inducing egg production. While the light from fluorescent bulbs is more intense, there are no more red rays produced, watt for watt, than from incandescent bulbs. In fact, there are fewer red rays from some types of fluorescent lights than from in- candescent lamps. The ”Birdseye 60" bulb has an advantage in that no reflector is required while another advantage is that dust settling on the bulb does not seem to impair its effective- ness because the upper half of the bulb is reflectorized. The "Birdseye 60" also has a low temperature filament there- by giving it longer life than an ordinary bulb. It is rated for 2000 hours compared to 750 hours for an ordinary bulb. Even though the test showed no outstanding advantage in favor of it, the "Birdseye 60" did give a slight advantage in egg production. Due to this reason, and its other ad- vantages, the "Birdseye 60" appeared very favorable in the test. 35 The 40 watt bulb plus a 16 inch reflector produced results equal to thoSe secured with any other type of light. The problem encountered, in the field, is that most poultry- men will not keep reflectors on the bulbs. This procedure cuts efficiency and requires a higher wattage bulb to get equal results, thus increasing operating cost. When bulbs become dirty, the efficiency drOps rapidly. From this test, it appears that any type of luminary will produce satisfactory egg production if maintained in good condition. The main prerequisite is to use the type of luminary that is economical to install and to operate and one that requires low maintenance costs. TEST II EFFECT OF VARIOUS INTENSITIES OF LIGHT ON EGG PRODUCTION Procedure: In this test, emphasis was placed on light intensity and its effect on egg production. The test was started October 1, 1959, using 1300 mature Single Comb White Leg- horn pullets of the Cornell Strain. They were randomly selected and housed in pens I, II, III, V, VI, VII, IX and x at the Old Cornell Poultry Research Farm placing 130 pullets in each pen measuring 20' by 20 feet. The pens were separated by solid partitions and had glass fronts facing south and were partially insulated. The birds were fed a commercial all mash laying ration(l6 percent proteinx free choice, and were allowed 45 feet of feeder space per 100 birds. During the cold part of the winter the birds were fed six pounds of all mash pellets in the litter in an effort to activate them and to help stir the litter. These pellets were fed at 3:30 P.M. each day. Each pen was equipped with one trough- type water fountain four feet in length which had an .emersion type water heater. The water pipes were protected from freezing by heating cables. Every pen also contained a hopper of oyster shells. Twenty-five open front nests 37 were located in each pen. The Ventilation consisted of the natural system using windows for inlets and flues for ex- hausts. The lighting systems tested included 60 watt in- candescent without reflectors, 40 watt fluorescent, 100 watt incandescent without reflectors and 15 watt incandes- cent red bulbs placed over the roosts. Each lighting set- up was replicated (Figure VI). The lights were controlled by time clocks to provide a 14 hour day. The clocks were set to turn the lights on at 5 A.M. and off at 8 A.M., then on again at 4 P.M. and off at 7 P.M. Each pen had two light fixtures 10 feet 0.0. placed equal distance between the front of the house and the perches, located at the back, except for the pens on the red light treatment. In this treatment,four 15 watt red bulbs were placed above the heads of the birds, as they sat on the roosts 5 feet 0.0. (Figure VI). Egg production and feed consumption records were recorded. Egg production records were computed weekly on a percentage basis and number of eggs per bird basis, while feed per dozen eggs was computed for each four week period. Mortality records were kept and recorded. The birds were all vaccinated for Newcastle disease, Infectious Bronchitis and Fowl Pox in accordance with the recommendations of the Cornell Poultry Pathology Department Results: While it is alleged by many peOple, that high light 38 a H» BEE m 3 p8: 83333 $3» HH «use a8 neon. Ho flHIeoa 338mm 383 > 2 Z HHH HH H ® 84 H H H mHm H mm. -m 8: H c. .m 3.. Umx x NM.H mm. mmom mbom x . WIH J x H I do N HHS mspmwocm wcmommm mrqm 3 tucooc . - man «.3 9H ness; mH SWN s .m yo me. H. m o Rmm .m mm.H m.em3 so m.w we.” mm. m mo. mmo. mmOo mo. f DU 8 8 H H H H um a3 H A.M. 8...... 80 WW H H om.m m.m am. Name 24.. 84m; 1...“ RH or. 8. mm. o . SA a. H IMH OH H H m H m HI m H H HHHS HHS H> I H H M W. H M. .m H H pom cm 0 o m 0 cm acmmmths N o “H e ommH 3mm: 03% H o AME.“ WW S . 3H: 3% . News ammo? as me pass: H mm. mm 1% emm W? m H fiHmH m .H Swims H Tm H- H 0mm 05 moMH no. no. no. m m 23 H 93 H t H H H O J Nmom OMm mmom I Rm «NH m. om. R. m e .m . . 2. H H n .mfi m. _ Wm. H Hm H HH EH onm H mm. W E G intensities will increase egg production, this claim was not proven in this test (Table IV, Figure VII). In fact, the two treatments with the highest light intensity, the fluorescent and the 100 watt, had the lowest egg production. This reduction in number of eggs cannot be explained, as there is no evidence to prove that bright light inhibits egg production. Egg production was consistently higher from the birds receiving light from the 15 watt red bulbs and the 60 watt bulbs than from those birds receiving the high intensity treatments. From this test, it would appear that high light in- tensities are not needed for maximum egg production. Feed efficiency varied between 4.1 pounds per dozen eggs in the red light pens to 4.5 pounds per dozen eggs in the 60 watt pens (Table V, Figure VIII). Mortality ranged from 2.25 percent in the 100 watt pens to 8.05 percent in the 60 watt control pens. This mortality was not excessive, in fact, it is below average. The results of this test showed no significant differences when analyzed statistically. It was concluded that all types of lights used gave equal results, that there is no benefit from using in- tensities of light higher than that obtained from a 60 watt incandescent bulb and that the 15 watt red bulbs over the roosts gave as good results as any other treatment. Discussion: For many years, there has been disagreement in the 1+0 m«.« mozm mo.« H3233. TS 0.3 98 .25 s .25. 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However, no scientific work reveals an advantage for light intensities above one foot candle at the feeder level. Several ref- » erences are cited in the review of literature but none showed any advantage for high light intensity. This test confirmed results of other investigations, in which no egg production increases resulted when high intensities were used. For some reason, the high intensity pens in this test produced slightly fewer eggs than the low intensity pens. There is no explanation for this as no work has been reported showing lower egg production from high intensities. The 15 watt red lights over the roosts were as satisfactory as the control treatment and more satisfactory than either the fluorescent or 100 watt treatment. If these 15 watt red lights are used, the bulbs must be no farther than 15 to 20 inches from the heads of the birds or the red rays may never reach the bird. The results of this test would indicate that there is no scientific Justification for having high light intensity in the poultry house. TEST III EFFECT OF TURNING LIGHTS ON DURING DARK DAYS ON EGG PRODUCTION Procedure: Many poultrymen believe that they must turn the electric lights on inside of their poultry houses during dark days to obtain maximum production. It was decided to check on the practicability of this practice. Test III was a preliminary test. At the particular time that it was to be run, facilities were not available to replicate the test. Nevertheless, the test was carried on to see if there would be a noticable difference in production between birds in a pen where a photo-electric cell was used compared to those in a control pen. Pens IV and VII (Figure I) were used for Test III because they were comparable in size and layout. Three hundred Single Comb White Leghorn pullets, of the same heredity as used in Test I, were housed in each pen on October 14, 1957. The photo-electric cell was placed be- hind one of the front windows in the feed room and was ad- Justed to turn on the lights when the light intensity reached a point where the caretaker ordinarily turned on the lights. This was adjusted by painting the glass red in front of the cell and then scraping it until the lights turned on at the intensity desired. This method proved 46 to be satisfactory. These birds were fed and cared for in the same manner as the birds in Test I. The lights in pens IV and VII con- sisted of five 40 watt incandescent bulbs without reflect- ors. These lights were on time clocks set in a similar manner as those in Test I, except that the photo-electric cell by-passed the clock during the day and turned on the lights when the cell was activated and called for light. Results: Even though many poultry authorities claim production will be increased by turning on the lights in the pens during dark days, results of this test did not bear out this contention. The test did show slightly increased egg production from the birds in the pen containing the photo-electric cell (Table VI, Figure IX). However, this slight increase was not statistically significant. Although no records were obtained on increased use of electricity, it was post- ulated that the use of the photo-electric cell was uneconom- ical. Feed efficiency of birds appeared to be consistently better in the photo-electric cell pen but again the differ- ence was not significant (Table VI). At no time, was there a great difference in egg pro- duction between treatment and control birds but feed efficiency varied considerably during January and February. The control pen was colder than the photo-electric cell pen 47 TABLE VI TEST III The Effect of Using a Photo-Electric Cell on Egg ProductIon andJFeed Efficiency PHOTO-CELL NO PHOTO-CELL 'PE?E§nt Pounds APercent Pounds Month Prod. Feed/Doz. Eggs Prod. Feed/Doz.Eggs October 45.0 6.4 46.0 6.5 November 67.7 4.1 68.9 4.1 December 65.3 4.4 61.7 5.1 'anuary 61.9 4.5 :0 5 5.5 February 47.4 4.8 42.0 6.4 March 51.3 4.5* 48.5 5.8 April 60.0 64.4 May 61.0 64.0 June 59.0 64.5 Average 57.6 56.7 *Feed records discontinued after this date. 4 NH ”$5me 053. max fun: ohm: .93“ o 63.. o 000 3.52 . woo _ _ _ _ _ _ _ _ .IIIIIIJ o usage: . \\\1// .x. / \\ / / 8 . II: III .5 2. H00 ovogm IIIII 0m HHmu UHHHUmeaosoea a peOHHHH saw 44H: mcom CH mUHHa Bonn COHpodpohm mmm mwmpcmouom zHcHuoz om. HHH emme uotqonpoad 883 queomeg 49 which may have accounted for the poorer feed conversion. Discussion: Little significance is attached to this test. It was monaof a trial than a test, due to the fact that the treat- ments were not replicated. However, the trial did give some indication of what might be eXpected. Practically no difference in egg production was shown between birds in the control pen and birds in the pen with the photo-electric cell. No record was kept of extra current used when the cell turned on the lights during the day. TEST IV EFFECT OF TURNING LIGHTS ON DURING DARK DAYS ON EGG PRODUCTION Procedure: Since no replicate had been possible in Test III, it was decided to repeat the test using replicate pens. On October 1, 1959, two hundred and sixty Single Comb White Leghorn pullets of the Cornell Strain were divided randomly into two pens of 130 birds each. The set- up was similar to that given for Test II except for the lighting treatment. The birds were placed in pen IV and VI at the Old Cornell Poultry Research Farm (Figure VI). They were both given 14 hours of light, controlled by time clocks. The clocks were set to turn on at 5 A.M. and off at 8 A.M. and then on again at 4 P.M. and off at‘7 P.M. In addition to this, these pens were equipped with a photo- electric cell to turn the lights on during dark days. Both pens were controlled by one cell which was adjustable for intensity. This cell was placed in the center of pen IV. It was adjusted to turn the lights on when the intensity in the pen reached a point where the caretaker would ordinarily turn on the lights had he adjusted the lighting himself. When intensity dropped below this point, the lights turned on and when it went above this point, the lights turned off. Management and pen arrangement were similar to that 51 as described in Test II. The control pens were pen II and pen IX (60 watt incandescent). Egg production was recorded daily and computed weekly for number of eggs per bird and the percentage egg production. Feed consumption was records ed and feed per dozen eggs was computed for each four week period. Results: As in Test III, egg production of the birds in the pens provided with photo-electric cells was approximately the same as that of birds in the control pens (Table VII and VIII, Figure X). The results were analyzed statistical- ly and were found to be not significant. In this test, a watt hour meter was attached to the photo-electric cell pens to measure the electric power used. The photo-electric cell pens used 335 kilowatts of electric- ity while the control pens (60 watt used 92 kilowatts). On the average, birds in the photo-electric cell pens pro- duced 1.3 more eggs per bird than birds in the control pens. Calculated at three cents per egg, this production gives an increased income of three and nine tenths cents per bird. The extra electricity used calculated at two cents per kilowatt, increased the electricity cost by three and seven tenths cents per bird leaving a net increase of two tenths cent per bird in the photo-electric cell equipped pens as compared to the control pens. This figure was calculated without including the cost of the control unit or the installation. TABLE VII TEST IV The Effect of Using a Photo-Electric Cell on Percentage Egg Production by week Photo Cell No Photo Cell Week Pen IV Pen VI Pen II Pen IX 73 71 57 77 2 72 73 65 79 3 75 72 7O 8O 4 75 78 67 81 5 74 74 7O 77 6 7O 69 68 75 7 67 69 66 62 8 67 66 64 63 9 64 63 62 64 10 62 64 62 63 ll 66 66 62 62 12 61 64 59 60 l} 62 62 59 62 14 63 65 59 6O 15 63 61 58 59 16 58 62 57 6O 17 59 59 55 61 18 57 59 58 61 19 52 57 56 64 2O 48 54 54 62 21 46 56 53 61 Ave. 63.6 65.0 61.0 66.0 Ave. of Reps. 54.3 53.5 TABLE VIII TEST IV The Effect of Using a Photo-Electric Cell on Eggs Per Bird by 4-Week Peribds 53 Photo-Cell No Photo-Cell Period IV VIlen numbers II Ix O-4 20.6 20.5 18.7 22.1 4-8 19.3 19.3 18.7 19.4 8-12 17.6 17.9 16.9 17.3 12-16 17.2 17.5 16.1 16.5 16-20 15.1 16.1 15.4 17.2 2lst. Week 3.2 3.8 3.6 4.3 TOTAL 93.0 95.1 89.4 97.3 Ave. of RepS. 9400 9303 Hm 54 ad ma NH oa ma 4H ma ma x mmaon HA OH m w w x8: HHoo owppocamuoeonm m enczpwx new nufix mama nH mvafla anm Gogoudepm wmm ommpnooammjwwxmoB HHoo oaonm oz I u n : fiHoQIOQOQm.Jl. " ll ’1 I, om ow uotqonpomd amended It was concluded from this test, that the use of a photo-electric cell was not economically sound nor would it be economical to use lights in the pens on dark days. Discussion: This test did not substantiate claims that increased egg production was a result of providing lights in the lay- ing pens on dark days. There were enough dark days when the photo-electric cell turned on the lights to use 335 kilowatt hours of electricity compared to 92 kilowatt hours used in the control pen. The benefit appears to be more of a psychological effect on the poultrymen than a benefit to the hens. Egg production of the birds in pens equipped with a photo-electric cell was increased only slightly as com- pared to that of birds in the control pens. The additional egg production was not enough to pay for the extra electric- ity used, the cost of the photo-electric cell and the installation of the cell. On the basis of the results from Test III and IV the installation of photo-electric cells in poultry houses cannot be recommended. TEST V THE EFFECT OF LIGHT RATIONING DURING THE GROWING PERIOD AND LAYING PERIOD ON EGG PRODUCTION Procedure: This test was conducted to determine the importance of the amount of light during the growing period and during the laying period on laying performance. Five hundred and ten pullet chicks were started on March 27, 1958. Three hundred and twelve of these were surplus Leghorn type chicks from the Western New York Ran- dom Sample test and the remaining 198 were purchased from a commercial hatchery. The chicks were randomly divided so that each treatment had the same number of each strain of surplus random sample birds and that, likewise, each test had equal numbers of commercial birds (Table IX). These 510 chicks were brooded in a conventional permanent brooder house under normal conditions until ten weeks of age. No lights were used during this period except for attraction lights under the hovers and the natural daylight from the windows. During the brooding period (1-8 weeks) the chicks were fed a commercial all mash chick starter and from 8-21 weeks the pullets were fed a commercial all mash growing TABLE IX Distribution of Chicks at 10 Weeks ongge Used In Light RationinggTest and Degree 0 Rationing from 10-21 Weeks of Age. Strain‘* 6 Hours Light Natural Natural Number Per Day Light Light 1 33 33 33 2 33 33 33 3 5 5 5 4 11 12 13 5 6 5 5 6 8 9 8 7 7 8 8 8 6 5 5 9 5 4 4 10 7 7 8 11 8 10 8 12 4 4 4 13 _21_ ii— _2.5__ 170 170 170 * Strains 1 and 2 were commercial strains: strains 3-13 were Random Sample extras. 58 ration. Fresh feed was added daily. The birds were all vaccinated for Newcastle Disease and Infectious Bronchitis according to recommendations of the Cornell Poultry Pathology Department. On June 6, 1958, at ten weeks of age the treatments were started. The pullets were weighed before being placed in their respective experimental quarters (Table X). At this time, 170 pullets were placed in two windowless pens and given six hours of light per day, from 6 A.M. to 12 noon. The other 340 pullets remained in naturally lighted pens until maturity (21 weeks of age). The windowless pens were ventilated by exhaust fans and air inlets, which were both covered and baffled, to prevent light entrance. All chores were done between 6 A.M. and 12 noon so the doors would not be opened during the dark period. No one was allowed in these pens during the dark period from 12 noon to 6 A.M. The pen arrangement and light intensities are shown (Figure XI). On August 22, 1958, the birds (85 per pen minus mortality losses) were placed in six windowless pens on another farm (Figure XII). At this time two more pens (170 pullets) were cut back to 6 hours of light per day (6 A.M. to 12 noon). The other two pens (170 pullets) were now given 14 hours of light per day. There were new four pens (340 pullets) on 6 hours of light and two pens (170 pullets) on a 14 hour day. This provided for a replicate of each treatment. Each pen was provided with two 40 watt TABLE X TEST V 59 Effect of Light Rationing From lO-2l Weeks of Age on 21 Week B6d Wei hts and on Total Feed ConsumptIon DfirIngTEIs PerIoa. Initial Body Treatment Weight at 10 Weeks (lbs.) 21 Weeks Body Weight(1bs.) Total Pounds Feed Consumption From 10-21 Weeks of Age 6 hours of light 1.82 Natural Light 1.84 Natural Light 1.84 3.23 3.38 3.40 13.75 13.91 14.17 6O HN mmncHh 2mm e883 8:38.32 23285.3 95 23 :33: 20383 33.5 2 $285 2mm amuse... > 58. sou 0&4 mo 233 8-3 sob 88m 85391 n8 8% 20E .8 waste Hmscmeflog 8088505 3...; 8 8 93.3.33 0 “U q I A n a . at H flllllllllll Flew II II .Kfleflm) MT “*1. W H H _ _ UV ) ll'llll 3 |)1-H\| 32m mm ushm mm «seem mm 35 we moamom 3 4on m .H s 3 as find sea and 23: oz 2.99.12 Heep; H832 1.322 Vhflflmmh GOflpflfihfl snow Nmuq< ammm 61 HHN $50?“ scam smegma 522023." 483222;; 23 :2»? 93383 8025 em 3383 Emma 830% a pm: .3 scram was?“ 2111.396 88 mama .8 c933 ASSESS All :0 Baillie .OH lilo .OHIIIVIAFIJO .OH IIIVAIJO .OHIIIX):© .OHIV HHH com H> com > com >H 8% HH com Hawk engages mm. a. a. a.fl m. «.H a. m. mm.” mm. H.H mm. ; m.a H.“ m.H o.N a.H w.H O O O O O 0 NA w H m4 ¥ 44 .. . W.H m4.a 4.~ fi.H fi.H \ m H m N a H mN.H N o.~ N.H m N H.H m.fl m m A.H m.H ~.fl A.H m.~ .uw e .e e 0 \ON 0 0 Mo 0 O ”O @N _ ~.H fi.H 0.” mm. H.H H.H N.H o.a ma. m.H mm.H mm. m. m. m. E... m. .1. m. 2. an 2.1m. m. 51 62 bulbs. Light intensity readings were made in various areas in each pen (Figure XII). The birds in pens I, II, IV and V were given six hours of light per day and pens III and VI were given 14 hours of light per day. Pens I and IV were replicates, pens II and V were replicates and pens III and VI were replicates. Starting August 22, 1958, pens I, II, IV and V were lighted from 6 A.M. until 12 noon. One week later and every week thereafter throughout the test, the lighting period was increased by an additional 15 minutes over the preceding week. The addition was always made at the end of the light- ing period with the 6 A.M. starting time kept constant. Pens III and VI remained on 14 hours of light throughout the laying year (12 months). Each pen was provided with four round hanging feeders with an 18 inch base and two "Johnson Cup" type water fountains which were equipped to prevent freeze-ups. Each pen had 15 nests of the regular open front type. Oyster shell was provided in a wall feeder and the birds were fed a commercial all mash laying ration.a6 percent). Eggs were gathered four times daily. Each time that the eggs were gathered, the hanging feeders were shaken so the feed would come down properly. Each afternoon, during cold weather, four pounds of layer mash pellets were fed in the litter to activate the birds to stir the litter. The litter remained in good condition all winter. These pens were insulated in the ceiling but this insulation did not prevent low tem- 63 peratures in these pens several times. The egg production and feed consumption were cal- culated monthly. Eggs were weighed November 11, December 16 and December 30 to see if the various lighting programs had any effect on egg size. Mortality figures were also recorded and computed. Results: Test V was conducted to determine the effect on age at sexual maturity, egg production, egg size and feed efficiency of rationing light in different amounts during the growing and laying period. Birds in one of the control pens produced the first. egg. However, eggs were produced from birds in two of the other pens before the birds in the second control pen started to lay (Table XI). The birds in Pen IV took the longest to start producing eggs while the birds in its rep- licate (pen I) were one of the first groups tested to start producing eggs. The birds in the control pens with 14 hours of light increased in production much more rapidly than the birds in either of the other treatments (Table XII, Table XIII, Figure XIII). There was little difference in average body weights of birds between treatments. Weights ranged from 3.0 pounds per bird in treatment five to 3.43 pounds per bird in treat- ments three and four. Birds receiving treatment two and treatment five, were the lightest. These were the birds that were reared with six hours of light from 10 weeks until 64- Jomo meg NONO no.2. Memo JoNO Gadfiofivokm #Gmohofi #3.... 32 .22 38 52... use as 85 22 to same woe. mud and and as «2 323.82 8.5: 333 93 28 Ram 4.2m gm 9% smomhd mém Tam 3mm TR TR 8% 2133\va Baum 5 H.om p.5m m.~m «.mm ~.om m.om Awm\aH\Hva2wHo= mmo .ooe o.m a.2 m.2 m.a 2.4 o.: ommo .Noo too soon .22 a.ooa 5.4a Hoa OHH a.aa o.mm .ox: ma.am coho too some .26 aa\w . afi\m «\m a\w ”who Hm\m _ mH\m moo soon“ no open 33 some £55 3! some on? .33 some .52 33 some .52. 52 fl 3.. .92 o 3.. .92 o .92 .2 m7. 5.2 o 3.. .92 o own .2 .3: .8. 23.. find u~m.m mo~.m *na.m am4.m *NN.m *mm.m Ammansosv omo mo .ox: Hm so pnmwo: .o>< Amo.qa xaa.ma *NH.2H amm.qa am~.ma «oo.ma A.ox: Hmuoavoufio too soon ogwwaaoa .osn o oewaaaon” onwaaaan .ot: o o:mwa»oo .oxs Hus.oxz 0H cornea modicum marge .3de 33 he; “33 133 1.84 .133 Rob - 232 .95 Ha > >H HHH HH H owooeoz com .oooo onus; ooooaoom no moaooom oooanoasom H> a > .- 3 es. Tocofioofioom Hx mama. 65 21 weeks of age. Eggs were weighed on November 11, December 12 and December 30 and showed little difference in egg size be- tween treatments (Table XI). The control group took an early lead in egg pro- duction and the other pens never caught up. All of these groups produced well, averaging from 241.} eggs per bird to 264.5 eggs per bird (Table XI). It was concluded,from the results of this test, that restricting light during the growing period and gradually increasing it throughout the laying period did not increase egg production but, rather, inhibited production somewhat. The control birds, reared in daylight and provided a 14 hour day during the laying year, produced the most eggs. However, the differences proved to be statistically not significant. Discussion: The light rationing test conducted did not sub- stantiate the claims, made in the pOpular press, showing considerably higher egg production by rationing light. Birds in all of the pens produced very satisfactorily. The lowest pen produced an average of 241 eggs per bird and the highest pen produced at an average of 264 eggs per bird. The only advantage, in favor of the control birds, was that they Jumped into an early lead, This situation occurred in September, October and November when eggs were highest in price, thereby giving these birds a larger advantage than 66 TABLE XII Effect of Bationed Light on Percentage Egg Production’bygfi6nth Month PERCENT EGG PRODUCTION Pen 1* Pen I1# Pen III+ Pen Iv* Pen v? Pen v1+ September 21 ll 50 10 25 52 October 54 61 79 6O 57 85 November 67 75 84 79 72 84 December 65 73 82 79 65 73 January 75 76 81 79 69 71 February 83 83 78 8O 79 69 March 84 83 74 79 81 68 April 82 79 75 79 77 71 May 73 76 71 74 73 70 June .73 74 69 72 71 68 July 67 68 63 68 68 64 August 63 62 56 64 61 58 Ave. Percent Production 67.3 68.4 71.8 68.6 66.5 69.4 Ave. of Rep. 68 67.5 70.6 *Pens I and IV were reared in daylight and cut to 6 hours of light at 21 weeks of age. Starting the 22nd. week their light period was increased 15 minutes each week throughout the laying year. #Pen II and V were provided 6 hours of light per day from 10 through 21 weeks of age. Starting the 22nd. week their light was increased 15 minutes each week throughout the laying year. +Pen III and VI were reared in daylight and were provided a 14 hour day from the 22nd. week throughout the laying year. All pens were windowless and birds received only artificial light. 67 TABLE XIII Effect of Rationed Light on Eggs Produced Per Bird by Month Month Pen I Pen II Pen III Pen IV Pen V PenWVI September 6.2 3.4 15.2 2.9 7.4 15.2 October 16.8 18.8 24.8 18.3 17.4 26.2 November 20.6 22.7 26.3 23.7 21.5 25.3 December 20.2 22.9 26.2 24.6 20.1 22.4 January 23.3 23.6 25.1 24.5 21.5 22.1 February 23.7 23.0 21.7 22.5 22.0 19.0 March 25.9 25.6 22.9 24.4 25.1 21.0 April 24.4 23.7 22.4 23.3 22.7 21.0 May 22.7 23.7 22.1 22.8 22.5 21.7 June 21.7 22.3 20.6 21.5 21.3 20.4 July 21.1 21.1 19.4 21.0 21.0 19.8 August 19.6 19.1 17.5 19.9 18.8 18.0 TOTAL 246.2 249.9 264.5 249.4 241.3 252.1 Ave. of Reps. 247.8 245.6 258.3 *Pen I and IV were reared in daylight and cut to 6 hours of light at 21 weeks of age. Starting the 22nd. week their light period was increased 15 minutes each week throughout the laying year. ” #Pen II and V were provided 6 hours of light per day from 10 through 21 weeks of age. Starting the 22nd. week their light was increased 15 minutes each week throughout the laying year. +Pen III and VI were reared in daylight and were provided a 14 hour day from the 22nd. week throughout the laying year. All pens were windowless and birds received only artificial light. Peroert. Production 68 9O 80 -" '\ 7o / \.\.,./-~.\ so / '. \.\ .. 50 -. 4o - 3O Sept. Nov. Jan. Mar. May July cm Lighting Lighting During 10-21 weeks Laying eriod . . . . 6 hours per day 6 hours + 15 minutes weekly NatuFal 6 hours + IS MTfifiEEE" weekly .-.-.-. N’aflu a1 11‘: houTS'TDe‘I'" tray Effect of Rationed Light on Percentage Egg ProductIBn by HBnth FIGURE XIII 69 indicated by egg production alone. By the time that the birds in the other pens caught up in production, egg prices ‘ had dropped. No advantage could be attributed to the light rationing nor did the birds mature faster or lay larger eggs in the light rationed pens. Little difference in mor- tality occurred between any of the treatments. Results from this test would indicate that a 14 hour day is sufficient for maximum egg production. To keep the day constant, it is probably best to provide part of the light at each end of the day. Test I: 1. Test II: 1. SUMMARY Egg production appeared to be equal where birds were exposed to any of the types of luminaries tested. It was concluded that the most practical luminary to use of those tested is the one that is the most economical to install and to Operate and one that requires the least maintenance. The cost of installing fluorescent lights does not Justify their use. The cost of the bulb and the extra electricity used, does not Justify the use of the 75 watt R-BOO The results and costs were approximately equal for the 40 watt bulb in a 16 inch reflector, the "Birdseye 60" and the 15 watt red bulbs; therefore, any one of these systems of lighting should be equally satisfactory. There appeared to be no difference in egg pro- duction attributable to any of the treatments Tests III 1. Test V: l. 71 tested. There was no benefit shown from using lights that produced higher intensities than obtained from a 40 watt bulb in a 16 inch relfector for each 200 square feet of floor space when placed over the work area. Fifteen watt red bulbs placed 18 inches above the birds' heads on the roosts gave egg production equal to any treatment used. and IV: There was no benefit shown from using a photo- electric cell to turn on the lights during dark days in these tests. The birds in the control pens laid as well as those in the pens controlled by a photo-electric cell. The cost of the photo-electric cell, its installa- tion and the cost of the extra electricity used could not be Justified by additional egg pro- duction. No benefit was shown from rationing light during the growing or laying period in this test. Egg production was slightly higher from birds on 72 the control treatment in which the birds were grown in daylight and provided a 14 hour day after maturity. This difference was not significant. Light rationing did not increase egg size. Age at date of first egg was not affected by light rationing. Age at time of fifty percent egg production was retarded by restricting light in this test. Mortality was approximately the same regardless of treatment. BIBLIOGRAPHY Barrott, H. G., and E. M. Pringle, 1951. Effect of Light on Early Growth. Journal of Nutrition. 45:265-74. Barrott, H. G., L. G. Schoenleber and L. E. Campbell, 1951. Effect of Ultraviolet on Egg Production. Poultry Science. 30:409-416. Bastian, J. W. and M. X. Zarrow, 1955. A New Hypothesis for the Asynchronous Ovulatory Cycle of the Domestic Hen. Poultry Science. 34:776-87. Bissonnette, T. H., 1931. Effect of Light of Different Intensities on Testis Activity. Physiology Zoology. 4:542-74. Bissonnette, T. H., 1933. 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Unpublished Personal Communications. Sturkie, P.D., 1954. Avian Physiology. Comstock Pub- lishing Associates, Ithaca, New York. P. 319. U) ykes, A. R., 1956. Short Day Length and Egg Production in the Fowl. Journal of Agricultural Science. 47:429-54. Tomhave, A. E., 1954. Influence of Artificial Lights During Rearing on the Egg Production of October Hatch- ed New Hampshires. Poultry Science. 33:725-29. Warren, D. C.,and H. M. Scott, 1936. Influence of Light on Ovulation in the Fowl. Journal of Experimental Zoology. 74:137-56. Whetham, E. 0., 1933. Factors Modifying Egg Production with Special Reference to Seasonal Changes. Journal of Agricultural Science. 23:383-418. \J (D Wilson, W. 0., and H. Abplanalp, 1954. Intermittent Light Stimuli in Egg Production Poultry Science. ‘t.__ _ -1- ‘1“ L? f z; .‘_--.- * 1’74 HUN? use. 3. ....