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Intermittent Watering and Feeding Programs for White Leghorn Layers1
Intermittent Watering and Feeding Programs for White Leghorn Layers1 R. J. S P I L L E R , 2 R. W . DORMINEY 3 AND G. H . ARSCOTT
Department of Poultry Science, Oregon State University, Corvallis, Oregon 97331 (Received for publication January 28, 1976)
POULTRY SCIENCE 55: 1871-1881, 1976
REVIEW OF LITERATURE
I
NTERMITTENT watering of White Leghorn (W.L.) layers has consistently resulted in improved feed efficiency (Maxwell and Lyle, 1957; Hill, 1969; and Hill and Richards, 1969.), but effects on egg production are less clear. Maxwell and Lyle (1957), who provided three 15-minute watering periods per day, and Wilson et al. (1965), providing two 2-hour periods per day, reported increased egg production in the intermittently watered hens. Hill (1969) and Hill and Richards (1969) pro-
1. Technical Paper No. 4073. Oregon Agricultural Experiment Station. This paper was developed in part from a thesis submitted by R. J. Spiller, a Chester M. Wilcox Memorial Scholarship recipient (1971-73), to the Graduate School, Oregon State University in partial fulfillment of the requirements for the Ph.D. degree. 2. Present Address: Chilson's Management Controls, Modesto, California 95351. 3. Deceased. Prior to his death he was a member of the Department of Poultry Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061.
vided water for five 15-minute and five 25minute periods per day and found that intermittent watering had no effect on egg production when initiated at 93 weeks of age and on the 169th day of lay, respectively. However, when intermittent watering was initiated at 41 weeks of age and on the first day of lay, respectively, hen-day egg production was reduced. Salverson (1959) and Knight (1970) reported no adverse effects from intermittent watering when they provided water for 15 minutes in a 60-minute period, for 30 minutes in a 120-minute period, or for six 30-minute periods per day. Wilson et al. (1965), reported reduced egg production from the intermittently watered layers when one 2-hour watering period per day was provided. Intermittent watering has also been shown to affect fecal dry matter content, internal egg quality and the cleanliness of waterers. Maxwell and Lyle (1957), provided hens three 15-minute watering periods per day, and Wilson et al. (1965), provided one 2-hour watering period per day, and found that intermittent
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ABSTRACT Three experiments were conducted to determine the effects of intermittent watering on White Leghorn layers. In addition in Exp. 2 the performance of layers subjected to intermittent feeding was also compared with the performance of control and intermittently watered layers. Providing hens two 1-hour or three 15-minute watering periods per day, after 5 months of lay on an ad lib. watering program, reduced egg production, feed per hen-day and weight gain, but had no effect on average egg weight (Exp. 1). When the three 15-minute watering periods were initiated prior to laying (Exp. 3), there was no effect on egg production, egg specific gravity or Haugh units; however, feed per hen-day, per egg, and per gram of egg, and average egg weight were reduced by 5.0, 11.0, 0.1, and 2.6 g., respectively. Providing five 15-minute watering periods per day had no effect on egg production, average egg weight or mortality. However, in two comparisons with controls (Exp. 2 & 3), feed per hen-day, per egg, and per gram of egg were reduced by 0.3 and 3.0, 7.7 and 9.0, and 0.14 and 0.17 g., respectively. Scheduling one 15-minute watering period each hour had no effect on egg production, feed intake or weight gain. Providing layers two 2-hour feeding periods per day significantly reduced feed consumption and weight gain, but had no significant effect on average egg weight or on egg production as compared to controls with feed and water ad lib. Haugh unit scores were higher when compared to the intermittent water treatments.
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R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
MATERIALS AND METHODS Three experiments were conducted during the years 1971-1974. The following common
4. Mettler gram scale, Model P-1000 (Mettler Scale Co., San Francisco, Cal.).
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The primary objective of this study was to investigate the effect of various intermittent watering regimes. In addition, intermittent watering programs were compared with an intermittent feeding program similar to that employed by Patel and McGinnis (1970) and McGinnis and Patel (1971).
procedures apply to all three experiments. Birds were housed in cages, three birds to a 43.2 x 43.2 cm. cage. Water troughs were made from 4.88 m. lengths of 2.54 cm. PVC plastic pipe which had been cut lengthwise. Solenoid valves and time clocks were used to regulate water flow. All birds were individually weighed at the beginning and the end of the experiment. All production records were maintained by 28day periods. Feed consumption was determined by weighing back feed on the morning of the first day of each 28-day period. In Exp. 1 and 2, average egg weight was determined by individually weighing all eggs laid during the last 3 days of each 28-day period. For Exp. 3, all eggs laid during the middle 3 days of each 28-day period were weighed. Eggs were weighed to the nearest one-tenth gram. 4 Egg mass (grams of egg produced/ replicate) was calculated by multiplying the 3-day sample average egg weight times the number of eggs laid for the 28-day period. Egg size was determined by classifying the eggs according to individual weight in the following categories: (1) Jumbo, 70.9 g. and up; (2) Extra Large, 63.8 to 70.8 g.; (3) Large, 56.7 to 63.7 g.; (4) Medium, 49.6 to 56.6 g.; (5) Small, 42.5 to 49.5 g.; and (6) Peewee, 42.4 g. and below. Percentages were calculated from the number of eggs included in each size category. Specific gravity and albumen quality were studied in Exp. 1 and 2. Specific gravity was determined by the procedure described by Arscott and Bernier (1961), using aqueous salt solutions scaled from 1.052 to 1.104 in increments of 0.004. After eggs from the 3-day sample had been dipped in the specific gravity solutions and individually weighed, they were broken on a table designed for examining egg quality. The albumen height
watering increased the dry matter content of the feces. Wilson et al. (1965) reported, with one 2-hour watering period per day, a Haugh unit improvement of 5.4 in albumen quality of eggs laid by intermittently watered hens. Salverson (1959), Hill (1969) and Knight (1970) found that the water troughs of intermittently watered layers were easier to keep clean. The results of intermittent feeding of W.L. layers have been inconsistent. Patel and McGinnis (1970) and McGinnis and Patel (1971) provided hens two 2-hour feeding periods per day and reported a 9 to 16% reduction in feed intake, weight gain and egg size but no adverse effect on egg production. Polin and Wolford (1972) found that layers provided two 1.5-hour feeding periods, two 2-hour feeding periods or one 4-hour feeding period per day laid at a significantly lower rate than the control group. Providing two 2.5-hour feeding periods had no significant effect on production. Harrison (1972) when reducing feeding time to two 2-hour feeding periods per day, observed a reduction in feed intake with little effect on egg production. Johnston et al. (1973) observed a 2.5, 1.1 and 1.3% reduction in egg production when layers were provided two 2-hour feeding periods per day through three lay cycles, respectively. Patel and McGinnis (1970), Polin and Wolford (1972), Johnston et al. (1973) and Harrison (1972) have all observed some reduction in average egg weight when employing intermittent feeding programs.
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INTERMITTENT WATERING AND FEEDING PROGRAMS
5. Manufactured by B. C. Ames Co., Waltham, Mass. 6. Designed by A. W. Brant and K. H. Norris. 7. The W.L. hens were the progeny of a rotational strain cross involving three distinct lines maintained at the Oregon Agricultural Experiment Station.
TABLE 1.—Composition of experimental diets Ingredients
Exp. 1
Exp. 2
Exp. 3
Corn, ground yellow 67.65 Fat, animal' 1.00 Fish meal (70% protein) — Meat & bone meal (50% protein) — Soybean meal (44% protein) 20.00 Alfalfa meal (20% 3.00 protein) Limestone flour 5.60 Oyster shell — Dicalcium phosphate 2.00 Salt, iodized 0.50 Vitamin-trace mineral mix # 2 2 0.25 Calculated Analyses Crude protein (%) 15.83 Methionine (%) 0.27 M.E. (kcal./kg.) 2895.00 kcal, / kg.: % protein 182.90
72.00
72.65
—
—
%
3.00
—
— 5.00
13.75
12.62
3.00 2.50 3.00
2.50 3.08 2.50
2.00 0.50
1.00 0.40
0.25
0.25
15.47 0.29 2924.00 189.00
15.32 0.26 2912.00 190.10
1 Fancy tallow stabilized with G-16 (Griffith Lab., Chicago, Illinois) which is composed of butylated hydroxytoluene, 14%; propyl gallate, 5%; proplyeneglycol, 2%; monoglyceride citrate, 35%; and vegetable oil, 36%. 2 Contributes/kg. of ration the following: Vit. A, 3,300 I.U.; Vit. D, 1,100 I.C.U.; riboflavin, 2.2 mg.; d-pantothenic acid, 5.5 mg.; niacin, 16.5 mg.: choline, 95.4 mg.; Vit. B12, 4.4 mg.; Vit. E, 1.10 I.U.; Vit. K, 0.25 mg.; Mn, 59.9 mg.; Fe, 20.1 mg.; Cu, 1.98 mg.; Co, 0.10 mg.; I 2 , 1.2 mg.; Zn, 27.5mg.;BHT, 125 mg.
3 was fed ad lib. and provided five 15-minute watering periods per day at 8:00 a.m., 11:30 a.m., 3:00 p.m., 6:30 p.m. and 10:00 p.m. Group 4 was provided water as per Group 1 and had access to feed from 8:00 a.m. to 10:00 a.m. and 3:00 p.m. to 5:00 p.m. Intermittent feeding was accomplished by manually removing the lids covering the feed troughs. All production records were maintained for ten 28-day periods, beginning when the pullets were 24 weeks of age and laying at a rate of 45%.
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was measured with a micrometer. 3 Haugh units were calculated on an Egg Quality Slide Rule, 6 using albumen height and egg weight. Data collected from all experiments were submitted to an analysis of variance and Duncan's new multiple range test (Steel and Torrie, 1960). Since the pullets utilized in Exp. 2 had been subjected to various treatments in the brooder house; data from this experiment were analyzed by means of a three factor analysis of variance. In Exp. 1, 126 Oregon State University W.L. hens 7 which had been in lay for approximately 5 months, were subjected to one of three treatments. Group 1, the control, had water in the free-flow water troughs concurrently with light (7:30 a.m. to 10:30 p.m.). Group 2, were provided two 1-hour watering periods daily (8:30-9:30 a.m., and 5:30-6:30 p.m.). Group 3 had access to water during three 15-minute periods daily at 8:00 a.m., 1:30 p.m. and 6:30 p.m. Feed for the three treatments was available ad libitum. All production records were maintained for a preliminary and five experimental 28-day periods. All hens received a ration calculated to contain 15.83% crude protein (C.P.) and 2895 kcal. M.E./kg. (Table 1). The 145 O.S.U. W.L. pullets utilized in Exp. 2 were subjected to one of four different treatments. These pullets were housed at 20 weeks of age and provided light from 7:45 a.m. to 12:00 midnight. All birds were fed a diet containing 15.47% C.P. and 2924 kcal. of M.E./kg. (Table 1). Group 1, the control, was fed ad lib. with water available concurrently with light. Group 2 was fed ad lib. and was provided a 15-minute watering period each hour from 8:00 a.m. to 11:00 p.m. Group
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R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
TABLE 2.—Performance of hens subjected to intermittent watering—Exp. V
Group
2
Avg. hen-day egg prod.
% l3 2
4
35
58.4a 51.8b 48.7b
Weight gain
Feed/ hen-day
Avg. egg wt.
8109.8a 16.0a 15.3a
g114.1a 100.9a 101.4a
g62.2a 62.5a 63.1a
Feed/ g. egg g3.19a 3.12a 3.30a
Feed/ egg g195.4a 194.8a 208.0a
Mort.
% 4.76a 2.44a 4.76a
'Values with differing lowercase superscripts are significantly different (P < .05). Each group consisted of 14 replicates of three birds each. 'Group 1 served as the control. "Group 2 had access to water from 8:30-9:30 A.M. and 5:30-6:30 P.M. 'Group 3 had access to water for 15-minute periods at 8:00 A.M., 1:30 P.M., and 6:30 P.M. 2
1. Providing water for two 1-hour or three 15-minute periods per day after five months of lay on ad lib. water resulted in a significant decline (P < .05) in hen-day egg production. Egg production of birds provided two 1-hour watering periods declined sharply during the first 28-day period (Fig. 1), but then increased each succeeding period until it nearly equalled that of the control during the fourth 28-day period. When access to water was limited to three 15-minute periods per day, egg production declined for the first two 28-day periods, but then climbed to nearly equal that of the controls by the fourth 28-day period.
Control Two 1-Hour periods per day Three 15 Min. perVods per day
RESULTS AND DISCUSSION Prelim.
Experiment 1. The performance of these hens is summarized in Table 2 and Figure 8. Provided gratuitously by Skylane Farms, Woodburn, Oregon and Babcock Industries, Ithaca, New York for which appreciation is expressed.
2 28-DAY
3 PERIOD
FIG. 1. Egg production curve of hens subjected to intermittent watering during a preliminary 28-day period, and during five, 28-day experimental periods—Exp. 1.
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The 144 Babcock B-300 pullets 8 utilized in Exp. 3 were subjected to one of four treatments. Group 1, the control, was provided water concurrent with light (8:00 a.m. to 12:15 a.m.); Group 2 had access to water for 15 minutes each hour from 8:15 a.m. to 11:15 p.m.; Group 3 had access to water during five 15-minute periods per day at 3.5 hour intervals (8:15 a.m., 11:45 a.m., 3:15 p.m., 6:45 p.m. and 10:15 p.m.). Group 4 had access to water during three 15-minute watering periods daily at 5.5 hour intervals (8:15 a.m., 1:45 p.m., and 6:45 p.m.). All treatments were fed a ration containing 15.32% C.P. and 2912 kcal. of M.E./kg. (Table 1). Feed was available ad lib. All production records were maintained for nine 28-day periods beginning when the pullets were 24 weeks of age and laying at a rate of 38% production. A limited number of fecal samples (ca 20 paired collections) were collected in Exp. 3 for dry matter determination on circular pans, 31.8 cm. in diameter, suspended beneath the cages for a 24 hour period. The collection pans.were then placed in a drying oven at 102° C. for 36 hours.
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The egg production of some three-bird replicates in the restricted groups was unaffected while others dropped to below 20%, with many hens going into a molt. On the other hand, no adverse effect on egg production was reported by Maxwell and Lyle (1957) when they alternated 6 week durations of water ad lib, and three 15-minute periods daily. Strain differences could possibly account for the dissimilarity in results.
TABLE 3.—Specific gravity of eggs from intermittently watered hens—Exp. V Group 2
Prelim.
1
l3
1.0850a 1.0835a 1.0833a
1.0806a 1.0810a 1.0808a
2
4
V
Specific Gravity by periods 3 2 1.0768b 1.0805a 1.0794a
1.0791b 1.0783b 1.0813a
4
5
1.0777b 1.0782b 1.0812a
1.0773a 1.0786a 1.0806a
'Values with differing lowercase superscripts are significantly different (P < .05). Each group consisted of two replicates of 21 birds each. 'Group 1 served as the control. "Group 2 had access to water from 8:30-9:30 A.M. and 5:30-6:30 P.M. 5 Group 3 had access to water for 15-minute periods at 8:00 A.M., 1:30 P.M. and 6:30 P.M. 2
TABLE 4.—Albumen quality
Group 2 l 2
3
4
35
Prelim.
1
83.4a 82.7a 83.7a
81.9a 81.5a 82.2a
of eggs from
iIntermittently watered hens—Exp. 1'
Haugh Units by periods 3 2 81.0a 81.1a 82.4a
81.0B 83.4AB 86.3A
4
5
76.0B 78.5AB 81.0A
74.4b 78.2ab 79.9a
'Values with differing uppercase superscripts are significantly different (P < .01); different lowercase superscripts indicate significance at P < .05. 2 Each group consisted of 14 replicates of three birds each. 3 Group 1 served as the control. "Group 2 had access to water from 8:30-9:30 A.M. and 5:30-6:30 P.M. "Group 3 had access to water for 15-minute periods at 8:00 A.M., 1:30 P.M. and 6:30 P.M.
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Differences in the average weight gained during the 20 week experimental period were not statistically significant, due to the inconsistent response of the hens to intermittent watering. However, the control hens gained an average of 110 g. while the two intermittently watered groups gained only 16.0 and 15.3 g. Average feed intake per hen-day was 114.1, 100.9, and 101.4 g. for the control, and for those with two 1-hour and three 15-minute periods, respectively. Thus, the two intermittent watering regimes resulted in feed savings
of 11.6 and 11.1%, respectively. Hens provided two 1-hour watering periods daily consumed 0.6 and 0.07 g. less feed per egg and per gram of egg, respectively, than did the control group, even though their hen-day egg production was 6.6% lower. No significant differences in average egg weight and mortality were observed. Significant differences in both internal and external quality were observed in Exp. 1. The specific gravity determinations are shown in Table 3. Eggs from both intermittently watered groups had significantly higher values (P < .05) than the control (Group 1) during period 2. Hens provided with three 15-minute watering periods daily (Group 3) laid eggs with higher specific gravity during the third and fourth 28-day periods. Albumen quality values are summarized in Table 4 and show that the group with three 15-minute periods laid eggs of significantly superior albumen quality during the third, fourth, and fifth 28-day periods.
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R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
TABLE 5.—Performance of White Leghorn pullets subjected to intermittent watering or feeding—Exp. 2'
Wilson et al. (1965) observed a 5.4 Haugh unit increase in albumen quality when hens were limited to one 2-hour watering period per day. In this study, intermittently watered hens laid eggs with better interior and exterior quality. However, it was not possible to determine if the improvement in interior and exterior egg quality was due to intermittent watering, or the hens molting and subsequently returning to production. Because the significantly higher Haugh unit and specific gravity values of eggs laid by intermittently watered hens were observed concurrently with the period of time that molted hens were returning to production (third, fourth and fifth 4-week periods), it is not possible to attribute the improvements in quality to intermittent watering per se. as will be noted in Exp. 2. Experiment 2. The performance of pullets subjected to intermittent watering or feeding is summarized in Table 5. The intermittent feeding of O. S. U. W. L. pullets for two 2-hour periods daily tended to reduce their hen-day
Mort. % 11.1a ll.la 13.9a 19.5a Feed/ g. egg8 g2.69a 2.67a 2.55b 2.76a
egg production in comparison with the control group (70.5 vs. 66.7%). Patel and McGinnis (1970) observed no decline in egg production when limiting feeding time in a manner similar to that used in this study. Polin and Wolford (1972), however, observed that hens given two 2-hour meals daily laid 8% fewer eggs. Hen-day egg production of 70.5, 74.6 and 73.4% was recorded for the control, and the groups with water 15-minutes each hour, and five 15-minute watering periods, respectively. These differences were not statistically significant. Hens receiving 15-minutes of water each hour laid significantly heavier (P < .05) eggs (Table 5) than the control and the group with two 2-hour feeding periods. Average egg weight for the control and those with five 15-minute watering periods was 60.7 and 61.5 g., respectively. These values show that intermittent watering in this study did not have an adverse effect on average egg weight. Also in comparison with the control, average egg weight was not altered by intermittent feeding. Patel and McGinnis (1970) and Polin and
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Hen-day Avg. egg Wt. egg prod.3 wt.4 gain5 % g. g. Control 70.5ab 60.7b 699a 15-min. H 2 0/hr. 74.6a 63.1a 698a 15-min. H 2 0 (five times/day) 73.4ab 61.5ab 544b Two, 2-hr. feedings 66.7b 61.0b 498b Egg/ Feed/ Feed/ Treatment hen-day hen-day6 egg7 gggControl 42.29a 114.4a 162.7ab 15-min. H 2 0/hr. 46.78a 124.0a 167.4a 15-min. H 2 0 (five times/day) 44.80a 114.1ab 115.0b Two, 2-hr. feedings 40.27a 109.7b 166.6a 1 Values with differing lowercase superscripts are significantly different (P < .05). 2 Each treatment consisted of 12 replicates of three birds each. 3 Avg. of hen-day egg production for the ten 28-day periods. 4 Avg. of egg wt. for the ten 28-day periods. 'Avg. wt. gained per pullet during the 40-week experiment. 6 Total feed consumed/total number of hen-days for the 40-week experiment. 'Total feed consumed/total number of eggs laid during the 40-week experiment. 8 Total feed consumed/total g. of egg for the 40-week experiment. Treatment2
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INTERMITTENT WATERING AND FEEDING PROGRAMS
TABLE 6.—Effects
provided water 15-minutes each hour consumed 10 g. more feed per hen-day, laid heavier eggs (63.1 vs. 60.7 g.) and produced at a higher rate (74.6 vs. 70.5%) than did the control. Although not statistically significant, the five 15-minute watering periods and the intermittent feeding groups consumed 0.3 and 4.7 g., respectively, less feed per hen day than did the control group. Significant differences (P < .05) in feed conversion were observed in Exp. 2 (Table 5). Layers provided five 15-minute watering periods required 7.7, 12.7, and 11.6 g. less feed to produce an egg than the control, the 15-minutes water per hour and the intermittently fed groups, respectively. Providing five 15-minute watering periods resulted in significantly less (P < .05) feed consumed (0.14, 0.12 and 0.21 g., respectively) to produce a gram of egg than the other treatments. Hill (1969) utilizing a similar watering regime, also observed an improvement in feed efficiency. Table 6 summarizes the effects of treatment on distribution of egg size. Layers provided water for 15-minutes each hour tended to lay fewer medium and large eggs, and more extra-large and jumbo eggs. This finding corresponds with the significantly heavier average egg weight observed with this treatment. Upon periodic observation, it was noted that all intermittently watered birds first satisfied their thirst when the solenoid valve opened, and then began to actively consume feed. One of the advantages claimed for
of intermittent watering and feeding programs on egg size distribution—Exp. 2' Egg size
Treatment2
Peewee & small
Medium
Large
Extra-large
%
%
%
%
%
25.04a 34.68a
4.24a 8.06a
30.53a 26.75a (P < .05).
2.07a 2.80a
Control 4.04a 20.05ab 46.64a 15-min. H 2 0/hr. 1.33a 15.04b 40.91a 15-min. H 2 0 (five times/day) 1.33a 20.70ab 45.38a Two, 2-hr. feedings 1.71a 22.51a 46.24a 'Values with differing lowercase superscripts are significantly different 2 Each treatment consisted of 12 replicates of three birds each.
Jumbo
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Wolford (1972) observed lower egg weight when hens were provided with two 2-hour feeding periods per day; however, Harrison (1972) utilizing the same feeding regime, observed no difference in egg weight. Layers provided with two 2-hour feeding periods or five 15-minute watering periods gained significantly less weight (P < .05) during the 40-week lay period than the control or those with 15-minutes water per hour. This would indicate that a greater percentage of the feed consumed by the intermittently watered (five 15-minute periods per day) pullets was converted into eggs rather than weight gain. Mortality for the four treatments was not significantly different. However, mortality for the intermittently fed layers reached 19.5%. The high mortality for this group reduced the cumulative hen-housed egg production to 55.7%. The other three treatments all laid above 66% on a hen-housed basis. There were no statistically significant differences in egg mass produced, however, the groups provided water 15-minutes each hour or five times daily, respectively, produced 10 and 5.9% more egg mass per hen-day than did the control group (Table 5). These differences resulted from the higher hen-day egg production and average egg weight observed in both intermittently watered groups. Intermittent watering did not result in a significant reduction in feed intake in this experiment. On the contrary, those pullets
1878
R. J. SPILLER, R. W .
TABLE 7.—Specific gravity of eggs from intermittent water and feeding programs—Exp.
Treatment 2 Control 15-min. H 2 0 / h r . 15-min. H 2 0 (five times/day) Two, 2-hr. feedings
DORMINEY AND G. H .
2
Sp. Gr. Pd. 1 Pd. 5 Pd. 9 1.0816A 1.0801 A 1.0786A 1.0826A 1.0802A 1.0777A 1.0835A 1.0816A 1.0783A 1.0812A 1.0818A 1.0807A
1 Values with differing uppercase superscripts are significantly different (P < .01). 2 Each treatment consisted of 12 replicates of three birds each.
TABLE 8.—Haugh units of eggs from intermittent watering and feeding programs—Exp 2' Haugh Units Treatment 2 PdTl PdT~5 Pd79" Controls 84.7A 82.4A 76.5AB 15-min. H 2 0 / h r . 83.1A 80.6A 73.8B 15-min. H 2 0 (five times/day) 82.2A 79.4A 72.3B Two, 2-hr. feedings 83.3A 82.7A 78.6A 1 Values with differing uppercase superscripts are significantly different (P < .01). 2
Each treatment consisted of 12 replicates of three birds each.
findings would suggest that the significant effects observed in Exp. 1 (Tables 3 and 4) were due to hens molting and subsequently returning to production rather than the intermittent watering treatments. Experiment 3. The performance of the intermittently watered Babcock B-300 pullets is presented in Table 9. Pullets provided with three 15-minute watering periods per day gained significantly less (P < .05) weight during 36 weeks of lay than did all other treatments. When water was available for 15-minute periods each hour or five times daily, gains were not different from the control. This is contrary to the results observed in Exp. 2 (Table 5). The conflicting findings may be explained on the basis of strain differences. Differences in hen-day egg production were not significant; however, all three intermittently watered groups laid at a higher rate than the control. In both Exp. 2 and 3, pullets provided five 15-minute watering periods laid at a numerically higher rate than the controls. Hill (1969) reported a slight reduction in hen-day egg production when pullets were provided five 15-minute watering periods per day when initiated at 21 weeks of age. Strain differences may again account for the dissimilarity of results. Differences could also be explained by water trough length. In this study (Exp. 1-3), the water traveled only 216 cm. (85") before reaching the last cage in each row. Under commercial conditions where troughs may be 91.4 m. (300') or more in length, the duration of the watering periods might have to be extended to insure that the last cage in each row received an adequate supply of water. The differences on the effects of providing three 15-minute watering periods per day between Exp. 1 and 3 can best be explained by noting the time of initiation of the watering programs. In Exp. 1, the watering program began in the middle of the lay cycle resulting
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automatic feeders is that the movement of the chain or auger promotes consumption. Perhaps in this experiment, the water flow, activated each hour served the same function as the automatic feeder, causing an increased feed intake and ultimately a significantly higher average egg weight. No significant differences were observed for specific gravity (Table 7). There were no significant Haugh unit differences for the intermittently watered layers and the controls at any period (Table 8). This also was the case for the intermittently fed birds except for the 9th period where a significantly higher value (P < .01) was noted when compared with the restricted water treatments. This difference could possibly be due to the fact that the intermittently watered groups were laying at a higher rate than the intermittently fed group (74.6 and 73.4 vs. 66.7%). These
ARSCOTT
INTERMITTENT WATERING AND FEEDING PROGRAMS
1879
TABLE 9.—Performance of White Leghorn pullets subjected to intermittent watering—Exp. 3' Treatment2 Control 15-min. H 2 0/hr. 15-min. H 2 0 (five times/day) 15-min. H 2 0 (three times/day) Treatment
Hen-day egg prod.3 % 74.8a 76.1a 77.7a 77.9a Egg/ hen-day5
Avg. egg wt. g. 57.2a 56.7a 57.1a 54.6b Feed/ hen-day6
Wt. gain4 g. 623a 663a 628a 524b Feed/ egg7
§•
§•
8-
Mort. % 0.0b ll.la 2.8b 0.0b Feed/ g. egg8 §•
in a significant decline in egg production, and an apparent force molt in some hens. In Exp. 3, the watering program was initiated prior to the onset of production, apparently allowing the pullets time to adapt to the watering regime. The most mortality, 11.1%, occurred in the group having water available 15-minutes each hour. Although this level proved significantly different, it is not excessively high. No mortality occurred in the control and three 15minute watering periods groups. The group provided three 15-minute watering periods per day consumed significantly less feed per hen-day than did the control and water 15 minutes each hour groups. The group provided five and three 15 minute watering periods daily consumed 97.3% and 95.5%, respectively, as much feed as the group with with water 15-minutes each hour, which consumed the same amount of feed per hen-day as did the control. Differences in feed consumed per egg were not statistically significant. The intermittently watered groups (15-minutes water each hour, five and
2.60a 2.57a 2.43a 2.50a
three 15-minute periods) required 98.6, 93.9 and 92.6% as much feed as the controls to produce an egg. These same groups required 98.8, 93.5 and 96.2% as much feed, respectively, as the control group to produce a gram of egg. The pullets provided five 15-minute 62
_
i
• i - i
—I
1
1
1
h
1
I
iJ^S^"
6
60
_ "-' 56 . „ m
s
54
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/
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h
52 UJ 50 _ > 48 -
-*
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58
o
/
M '
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Control
— - Three I5-Min. periods /day
1
1
_ -
A—A O—O
\?
-
A—A 1 1
Five 15-Min. periods /day I5-Min. period each hour i
i
i
I
i
I
3 4 5 6 7 28-DAY PERIOD
FIG. 2. Average egg weights of intermittently watered hens during nine 28-day experimental periods—Exp. 3.
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Control 42.8a Ilia 148a 15-min. H 2 0/hr. 43.1a 111a 146a 15-min. H 2 0 (five times/day) 44.4a 108ab 139a 15-min. H 2 0 (three times/day) 42.6a 106b 137a •Values with differing lowercase superscripts are significantly different (P < .05). 2 Each group contained two replicates of 18 birds each. 'Total number of eggs laid/total number of hen-days for the 36-week experiment. 4 Avg. wt. gained per hen during the 36-week experiment. 5 Total g. of egg produced/total number of hen-days for the 36-week experiment. 6 Total feed consumed/total number of hen-days for the 36-week experiment. 7 Total feed consumed/total number of eggs laid during the 36-week experiment. 8 Total feed consumed/total g. of eggs for the 36-week experiment.
1880
R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
TABLE 10.—Egg size distribution of Babcock B-300 layers as affected by intermittent watering—Exp. 3' Egg Size Treatment2
Peewee & small
Medium
Large
Extra-large
%
%
%
%
Control 8.61a 38.49a 9.82a 42.70a 15-min. H 2 0/hr. 12.55a 31.63a 6.95a 48.44a 15-min. H 2 0 (five times/day) 9.46a 36.44a 42.48a 11.63a 15-min. H 2 0 (three times/day) 20.26a 41.46a 31.25b 6.91a 'Values with differing lowercase superscripts are significantly different (P < .05). 2 Each treatment consisted of two replicates of 18 birds each.
The egg size distribution is shown in Table 10. Pullets watered three times daily laid significantly fewer large eggs and tended to lay more peewee, small and medium eggs, and fewer extra-large eggs. The other two intermittent watering regimes did not alter egg size distribution.
% 0.40a 0.44a 0.00a 0.14a
There were no significant differences in the moisture content of the fecal samples. The average dry matter content of the feces from the control, and the three or five 15minute watering periods was 28.5, 29.0 and 24.2%, respectively. Since the laying facilities were not temperature controlled, the birds were exposed to temperatures in excess of 26.7° C. on many occasions. Periodically maximum ambient temperatures in excess of 32.2° C. were recorded. However, at no time did the intermittently watered layers appear to be more heat stressed than the control group. REFERENCES Arscott, G. H., and P. E. Bernier, 1961. Application of specific gravity to the determination of eggshell thickness. In: Agricultural Science Laboratory Excercises for High School Students. Agricultural Science No. 2. School of Agriculture, Oregon State University. Harrison, P. C , 1972. Two feeding periods best in limiting time feeding. Poultry Digest, 31: 148. Hill, A. T., 1969. Phase watering for laying stock. Can. Poultry Rev. 93: 38. Hill, A. T., and J. F. Richards, 1969. Consequences of limiting cage layer watering time. Poultry Sci. 48: 1819. Johnston, G. W., M. H. Swanson and C. A. Salverson, 1973. Feed restriction through three lay cycles. Poultry Institute Proceedings, Univ. Cal. Agric. Ext. pp. 8-13. Knight, H. F., 1970. Controlled water systems for cages. Poultry Digest, 29: 84-85.
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watering periods per day tended to produce eggs more efficiently, concurring with the findings in Exp. 2. A significant difference (P < .05) was observed in average egg weight. Figure 2 shows the average egg weights of the control and intermittently watered groups for each 4-week period. Pullets provided three 15minute watering periods per day consistently laid significantly (P < .05) smaller eggs than did birds in the other three treatments. The reduction in average egg weight in the first five periods is undesirable because of the large number of peewee, small and medium eggs. However, a reduction in egg size may be desirable after the sixth period when a larger percentage of the eggs laid are large, extra-large and jumbo. Producers selling to a wholesaler, receiving little or no premium for extra-large over large and only a small premium for jumbos, may benefit economically from reductions in the numbers of extra-large and jumbo eggs, and in feed intake as a result of this intermittent watering regime.
Jumbo
INTERMITTENT WATERING AND FEEDING PROGRAMS
Maxwell, B. J., and J. B. Lyle, 1957. Restricted water for wet dropping prevention. Poultry Sci. 36: 921922. McGinnis,J.,and P. R. Patel, 1971. Time-limit feeding. Poultry Digest, 33: 253. Patel, P. R., and J. McGinnis, 1970. Effect of restricting feeding time on feed consumption, egg production, and body weight gain of Leghorn pullets. Poultry Sci. 49: 1425. Polin, D., and J. H. Wolford, 1972. The effect of
1881
meal-eating on egg production and body weight of White Leghorn chickens. Poultry Sci. 51:1109-1118. Salverson, C. A., 1959. Water restriction for layers. Pacific Poultryman, 65(21): 58-59. Steel, R. G. D., and J. H. Torrie, 1960. Principles and Procedures of Statistics. McGraw Hill Co. Inc., New York, New York. Wilson, H. R., C. F. Wright, R. W. Dorminey and I. E. Jones, 1965. Water restriction for caged layers. Sunshine State Agri. Res. Rep. 10(4): 11.
SARDUL S. GURAYA AND R. K. CHALANA
Department of Zoology, College of Basic Sciences & Humanities, Punjab Agricultural University, Punjab, India (Received for publication January 29, 1976)
ABSTRACT A histochemical study has been made of seasonal fluctuations in the follicular atresia and interstitial gland tissue with the ovarian cycles of the house sparrow (Passer domesticus). The atresia of primordial oocytes forms the predominant feature of the quiescentwinter ovary. The building up of interstitial gland tissue of thecal origin, which precedes the breeding activity, is closely related to the atresia of previtellogenic follicles of variable sizes. Interstitial gland cells which accumulate lipid droplets consisting of cholesterol, and/or its esters, triglycerides and some phospholipids, are the steroid secretors. The possible functional significance of different-sized follicular atresia in relation to follicular growth and breeding activity is discussed. POULTRY SCIENCE 55: 1881-1885, 1976
INTRODUCTION
A
S in other vertebrates (Guraya, 1973), follicular atresia also forms a conspicuous feature of the avian ovary, which has been distinguished into different types depending upon the stepwise size gradation at which the follicles become atretic (Kern, 1972; Erpino, 1973). But the physiological significance of different-sized atretic follicles is poorly understood during the reproductive cycle. Using histological and histochemical techniques, the present study on the ovary of house sparrow (Passer domesticus) was undertaken to determine the nature of relationships between the follicular growth and atresia and building up of interstitial gland tissue throughout the year. The results of
this study will form the basis for future experimental studies on the induction of follicular atresia and possible secretory role of atretic follicles. In the previous studies, very little attention has been paid to the atresia of primordial follicles, which is also investigated here. MATERIAL AND METHODS Three to five female specimens of house sparrows were collected at weekly intervals throughout the year. The fixatives used for the histochemistry of lipids included formaldehyde-calcium and weak Bouin's solution. After fixation, the material was postchromed in dichromate-calcium and embedded in gelatin. Frozen gelatin sections were
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Histochemical Observations on the Seasonal Fluctuations in the Follicular Atresia and Interstitial Gland Tissue in the House Sparrow Ovary
Department of Poultry Science, Oregon State University, Corvallis, Oregon 97331 (Received for publication January 28, 1976)
POULTRY SCIENCE 55: 1871-1881, 1976
REVIEW OF LITERATURE
I
NTERMITTENT watering of White Leghorn (W.L.) layers has consistently resulted in improved feed efficiency (Maxwell and Lyle, 1957; Hill, 1969; and Hill and Richards, 1969.), but effects on egg production are less clear. Maxwell and Lyle (1957), who provided three 15-minute watering periods per day, and Wilson et al. (1965), providing two 2-hour periods per day, reported increased egg production in the intermittently watered hens. Hill (1969) and Hill and Richards (1969) pro-
1. Technical Paper No. 4073. Oregon Agricultural Experiment Station. This paper was developed in part from a thesis submitted by R. J. Spiller, a Chester M. Wilcox Memorial Scholarship recipient (1971-73), to the Graduate School, Oregon State University in partial fulfillment of the requirements for the Ph.D. degree. 2. Present Address: Chilson's Management Controls, Modesto, California 95351. 3. Deceased. Prior to his death he was a member of the Department of Poultry Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061.
vided water for five 15-minute and five 25minute periods per day and found that intermittent watering had no effect on egg production when initiated at 93 weeks of age and on the 169th day of lay, respectively. However, when intermittent watering was initiated at 41 weeks of age and on the first day of lay, respectively, hen-day egg production was reduced. Salverson (1959) and Knight (1970) reported no adverse effects from intermittent watering when they provided water for 15 minutes in a 60-minute period, for 30 minutes in a 120-minute period, or for six 30-minute periods per day. Wilson et al. (1965), reported reduced egg production from the intermittently watered layers when one 2-hour watering period per day was provided. Intermittent watering has also been shown to affect fecal dry matter content, internal egg quality and the cleanliness of waterers. Maxwell and Lyle (1957), provided hens three 15-minute watering periods per day, and Wilson et al. (1965), provided one 2-hour watering period per day, and found that intermittent
1871
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ABSTRACT Three experiments were conducted to determine the effects of intermittent watering on White Leghorn layers. In addition in Exp. 2 the performance of layers subjected to intermittent feeding was also compared with the performance of control and intermittently watered layers. Providing hens two 1-hour or three 15-minute watering periods per day, after 5 months of lay on an ad lib. watering program, reduced egg production, feed per hen-day and weight gain, but had no effect on average egg weight (Exp. 1). When the three 15-minute watering periods were initiated prior to laying (Exp. 3), there was no effect on egg production, egg specific gravity or Haugh units; however, feed per hen-day, per egg, and per gram of egg, and average egg weight were reduced by 5.0, 11.0, 0.1, and 2.6 g., respectively. Providing five 15-minute watering periods per day had no effect on egg production, average egg weight or mortality. However, in two comparisons with controls (Exp. 2 & 3), feed per hen-day, per egg, and per gram of egg were reduced by 0.3 and 3.0, 7.7 and 9.0, and 0.14 and 0.17 g., respectively. Scheduling one 15-minute watering period each hour had no effect on egg production, feed intake or weight gain. Providing layers two 2-hour feeding periods per day significantly reduced feed consumption and weight gain, but had no significant effect on average egg weight or on egg production as compared to controls with feed and water ad lib. Haugh unit scores were higher when compared to the intermittent water treatments.
1872
R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
MATERIALS AND METHODS Three experiments were conducted during the years 1971-1974. The following common
4. Mettler gram scale, Model P-1000 (Mettler Scale Co., San Francisco, Cal.).
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The primary objective of this study was to investigate the effect of various intermittent watering regimes. In addition, intermittent watering programs were compared with an intermittent feeding program similar to that employed by Patel and McGinnis (1970) and McGinnis and Patel (1971).
procedures apply to all three experiments. Birds were housed in cages, three birds to a 43.2 x 43.2 cm. cage. Water troughs were made from 4.88 m. lengths of 2.54 cm. PVC plastic pipe which had been cut lengthwise. Solenoid valves and time clocks were used to regulate water flow. All birds were individually weighed at the beginning and the end of the experiment. All production records were maintained by 28day periods. Feed consumption was determined by weighing back feed on the morning of the first day of each 28-day period. In Exp. 1 and 2, average egg weight was determined by individually weighing all eggs laid during the last 3 days of each 28-day period. For Exp. 3, all eggs laid during the middle 3 days of each 28-day period were weighed. Eggs were weighed to the nearest one-tenth gram. 4 Egg mass (grams of egg produced/ replicate) was calculated by multiplying the 3-day sample average egg weight times the number of eggs laid for the 28-day period. Egg size was determined by classifying the eggs according to individual weight in the following categories: (1) Jumbo, 70.9 g. and up; (2) Extra Large, 63.8 to 70.8 g.; (3) Large, 56.7 to 63.7 g.; (4) Medium, 49.6 to 56.6 g.; (5) Small, 42.5 to 49.5 g.; and (6) Peewee, 42.4 g. and below. Percentages were calculated from the number of eggs included in each size category. Specific gravity and albumen quality were studied in Exp. 1 and 2. Specific gravity was determined by the procedure described by Arscott and Bernier (1961), using aqueous salt solutions scaled from 1.052 to 1.104 in increments of 0.004. After eggs from the 3-day sample had been dipped in the specific gravity solutions and individually weighed, they were broken on a table designed for examining egg quality. The albumen height
watering increased the dry matter content of the feces. Wilson et al. (1965) reported, with one 2-hour watering period per day, a Haugh unit improvement of 5.4 in albumen quality of eggs laid by intermittently watered hens. Salverson (1959), Hill (1969) and Knight (1970) found that the water troughs of intermittently watered layers were easier to keep clean. The results of intermittent feeding of W.L. layers have been inconsistent. Patel and McGinnis (1970) and McGinnis and Patel (1971) provided hens two 2-hour feeding periods per day and reported a 9 to 16% reduction in feed intake, weight gain and egg size but no adverse effect on egg production. Polin and Wolford (1972) found that layers provided two 1.5-hour feeding periods, two 2-hour feeding periods or one 4-hour feeding period per day laid at a significantly lower rate than the control group. Providing two 2.5-hour feeding periods had no significant effect on production. Harrison (1972) when reducing feeding time to two 2-hour feeding periods per day, observed a reduction in feed intake with little effect on egg production. Johnston et al. (1973) observed a 2.5, 1.1 and 1.3% reduction in egg production when layers were provided two 2-hour feeding periods per day through three lay cycles, respectively. Patel and McGinnis (1970), Polin and Wolford (1972), Johnston et al. (1973) and Harrison (1972) have all observed some reduction in average egg weight when employing intermittent feeding programs.
1873
INTERMITTENT WATERING AND FEEDING PROGRAMS
5. Manufactured by B. C. Ames Co., Waltham, Mass. 6. Designed by A. W. Brant and K. H. Norris. 7. The W.L. hens were the progeny of a rotational strain cross involving three distinct lines maintained at the Oregon Agricultural Experiment Station.
TABLE 1.—Composition of experimental diets Ingredients
Exp. 1
Exp. 2
Exp. 3
Corn, ground yellow 67.65 Fat, animal' 1.00 Fish meal (70% protein) — Meat & bone meal (50% protein) — Soybean meal (44% protein) 20.00 Alfalfa meal (20% 3.00 protein) Limestone flour 5.60 Oyster shell — Dicalcium phosphate 2.00 Salt, iodized 0.50 Vitamin-trace mineral mix # 2 2 0.25 Calculated Analyses Crude protein (%) 15.83 Methionine (%) 0.27 M.E. (kcal./kg.) 2895.00 kcal, / kg.: % protein 182.90
72.00
72.65
—
—
%
3.00
—
— 5.00
13.75
12.62
3.00 2.50 3.00
2.50 3.08 2.50
2.00 0.50
1.00 0.40
0.25
0.25
15.47 0.29 2924.00 189.00
15.32 0.26 2912.00 190.10
1 Fancy tallow stabilized with G-16 (Griffith Lab., Chicago, Illinois) which is composed of butylated hydroxytoluene, 14%; propyl gallate, 5%; proplyeneglycol, 2%; monoglyceride citrate, 35%; and vegetable oil, 36%. 2 Contributes/kg. of ration the following: Vit. A, 3,300 I.U.; Vit. D, 1,100 I.C.U.; riboflavin, 2.2 mg.; d-pantothenic acid, 5.5 mg.; niacin, 16.5 mg.: choline, 95.4 mg.; Vit. B12, 4.4 mg.; Vit. E, 1.10 I.U.; Vit. K, 0.25 mg.; Mn, 59.9 mg.; Fe, 20.1 mg.; Cu, 1.98 mg.; Co, 0.10 mg.; I 2 , 1.2 mg.; Zn, 27.5mg.;BHT, 125 mg.
3 was fed ad lib. and provided five 15-minute watering periods per day at 8:00 a.m., 11:30 a.m., 3:00 p.m., 6:30 p.m. and 10:00 p.m. Group 4 was provided water as per Group 1 and had access to feed from 8:00 a.m. to 10:00 a.m. and 3:00 p.m. to 5:00 p.m. Intermittent feeding was accomplished by manually removing the lids covering the feed troughs. All production records were maintained for ten 28-day periods, beginning when the pullets were 24 weeks of age and laying at a rate of 45%.
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was measured with a micrometer. 3 Haugh units were calculated on an Egg Quality Slide Rule, 6 using albumen height and egg weight. Data collected from all experiments were submitted to an analysis of variance and Duncan's new multiple range test (Steel and Torrie, 1960). Since the pullets utilized in Exp. 2 had been subjected to various treatments in the brooder house; data from this experiment were analyzed by means of a three factor analysis of variance. In Exp. 1, 126 Oregon State University W.L. hens 7 which had been in lay for approximately 5 months, were subjected to one of three treatments. Group 1, the control, had water in the free-flow water troughs concurrently with light (7:30 a.m. to 10:30 p.m.). Group 2, were provided two 1-hour watering periods daily (8:30-9:30 a.m., and 5:30-6:30 p.m.). Group 3 had access to water during three 15-minute periods daily at 8:00 a.m., 1:30 p.m. and 6:30 p.m. Feed for the three treatments was available ad libitum. All production records were maintained for a preliminary and five experimental 28-day periods. All hens received a ration calculated to contain 15.83% crude protein (C.P.) and 2895 kcal. M.E./kg. (Table 1). The 145 O.S.U. W.L. pullets utilized in Exp. 2 were subjected to one of four different treatments. These pullets were housed at 20 weeks of age and provided light from 7:45 a.m. to 12:00 midnight. All birds were fed a diet containing 15.47% C.P. and 2924 kcal. of M.E./kg. (Table 1). Group 1, the control, was fed ad lib. with water available concurrently with light. Group 2 was fed ad lib. and was provided a 15-minute watering period each hour from 8:00 a.m. to 11:00 p.m. Group
1874
R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
TABLE 2.—Performance of hens subjected to intermittent watering—Exp. V
Group
2
Avg. hen-day egg prod.
% l3 2
4
35
58.4a 51.8b 48.7b
Weight gain
Feed/ hen-day
Avg. egg wt.
8109.8a 16.0a 15.3a
g114.1a 100.9a 101.4a
g62.2a 62.5a 63.1a
Feed/ g. egg g3.19a 3.12a 3.30a
Feed/ egg g195.4a 194.8a 208.0a
Mort.
% 4.76a 2.44a 4.76a
'Values with differing lowercase superscripts are significantly different (P < .05). Each group consisted of 14 replicates of three birds each. 'Group 1 served as the control. "Group 2 had access to water from 8:30-9:30 A.M. and 5:30-6:30 P.M. 'Group 3 had access to water for 15-minute periods at 8:00 A.M., 1:30 P.M., and 6:30 P.M. 2
1. Providing water for two 1-hour or three 15-minute periods per day after five months of lay on ad lib. water resulted in a significant decline (P < .05) in hen-day egg production. Egg production of birds provided two 1-hour watering periods declined sharply during the first 28-day period (Fig. 1), but then increased each succeeding period until it nearly equalled that of the control during the fourth 28-day period. When access to water was limited to three 15-minute periods per day, egg production declined for the first two 28-day periods, but then climbed to nearly equal that of the controls by the fourth 28-day period.
Control Two 1-Hour periods per day Three 15 Min. perVods per day
RESULTS AND DISCUSSION Prelim.
Experiment 1. The performance of these hens is summarized in Table 2 and Figure 8. Provided gratuitously by Skylane Farms, Woodburn, Oregon and Babcock Industries, Ithaca, New York for which appreciation is expressed.
2 28-DAY
3 PERIOD
FIG. 1. Egg production curve of hens subjected to intermittent watering during a preliminary 28-day period, and during five, 28-day experimental periods—Exp. 1.
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The 144 Babcock B-300 pullets 8 utilized in Exp. 3 were subjected to one of four treatments. Group 1, the control, was provided water concurrent with light (8:00 a.m. to 12:15 a.m.); Group 2 had access to water for 15 minutes each hour from 8:15 a.m. to 11:15 p.m.; Group 3 had access to water during five 15-minute periods per day at 3.5 hour intervals (8:15 a.m., 11:45 a.m., 3:15 p.m., 6:45 p.m. and 10:15 p.m.). Group 4 had access to water during three 15-minute watering periods daily at 5.5 hour intervals (8:15 a.m., 1:45 p.m., and 6:45 p.m.). All treatments were fed a ration containing 15.32% C.P. and 2912 kcal. of M.E./kg. (Table 1). Feed was available ad lib. All production records were maintained for nine 28-day periods beginning when the pullets were 24 weeks of age and laying at a rate of 38% production. A limited number of fecal samples (ca 20 paired collections) were collected in Exp. 3 for dry matter determination on circular pans, 31.8 cm. in diameter, suspended beneath the cages for a 24 hour period. The collection pans.were then placed in a drying oven at 102° C. for 36 hours.
1875
INTERMITTENT WATERING AND FEEDING PROGRAMS
The egg production of some three-bird replicates in the restricted groups was unaffected while others dropped to below 20%, with many hens going into a molt. On the other hand, no adverse effect on egg production was reported by Maxwell and Lyle (1957) when they alternated 6 week durations of water ad lib, and three 15-minute periods daily. Strain differences could possibly account for the dissimilarity in results.
TABLE 3.—Specific gravity of eggs from intermittently watered hens—Exp. V Group 2
Prelim.
1
l3
1.0850a 1.0835a 1.0833a
1.0806a 1.0810a 1.0808a
2
4
V
Specific Gravity by periods 3 2 1.0768b 1.0805a 1.0794a
1.0791b 1.0783b 1.0813a
4
5
1.0777b 1.0782b 1.0812a
1.0773a 1.0786a 1.0806a
'Values with differing lowercase superscripts are significantly different (P < .05). Each group consisted of two replicates of 21 birds each. 'Group 1 served as the control. "Group 2 had access to water from 8:30-9:30 A.M. and 5:30-6:30 P.M. 5 Group 3 had access to water for 15-minute periods at 8:00 A.M., 1:30 P.M. and 6:30 P.M. 2
TABLE 4.—Albumen quality
Group 2 l 2
3
4
35
Prelim.
1
83.4a 82.7a 83.7a
81.9a 81.5a 82.2a
of eggs from
iIntermittently watered hens—Exp. 1'
Haugh Units by periods 3 2 81.0a 81.1a 82.4a
81.0B 83.4AB 86.3A
4
5
76.0B 78.5AB 81.0A
74.4b 78.2ab 79.9a
'Values with differing uppercase superscripts are significantly different (P < .01); different lowercase superscripts indicate significance at P < .05. 2 Each group consisted of 14 replicates of three birds each. 3 Group 1 served as the control. "Group 2 had access to water from 8:30-9:30 A.M. and 5:30-6:30 P.M. "Group 3 had access to water for 15-minute periods at 8:00 A.M., 1:30 P.M. and 6:30 P.M.
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Differences in the average weight gained during the 20 week experimental period were not statistically significant, due to the inconsistent response of the hens to intermittent watering. However, the control hens gained an average of 110 g. while the two intermittently watered groups gained only 16.0 and 15.3 g. Average feed intake per hen-day was 114.1, 100.9, and 101.4 g. for the control, and for those with two 1-hour and three 15-minute periods, respectively. Thus, the two intermittent watering regimes resulted in feed savings
of 11.6 and 11.1%, respectively. Hens provided two 1-hour watering periods daily consumed 0.6 and 0.07 g. less feed per egg and per gram of egg, respectively, than did the control group, even though their hen-day egg production was 6.6% lower. No significant differences in average egg weight and mortality were observed. Significant differences in both internal and external quality were observed in Exp. 1. The specific gravity determinations are shown in Table 3. Eggs from both intermittently watered groups had significantly higher values (P < .05) than the control (Group 1) during period 2. Hens provided with three 15-minute watering periods daily (Group 3) laid eggs with higher specific gravity during the third and fourth 28-day periods. Albumen quality values are summarized in Table 4 and show that the group with three 15-minute periods laid eggs of significantly superior albumen quality during the third, fourth, and fifth 28-day periods.
1876
R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
TABLE 5.—Performance of White Leghorn pullets subjected to intermittent watering or feeding—Exp. 2'
Wilson et al. (1965) observed a 5.4 Haugh unit increase in albumen quality when hens were limited to one 2-hour watering period per day. In this study, intermittently watered hens laid eggs with better interior and exterior quality. However, it was not possible to determine if the improvement in interior and exterior egg quality was due to intermittent watering, or the hens molting and subsequently returning to production. Because the significantly higher Haugh unit and specific gravity values of eggs laid by intermittently watered hens were observed concurrently with the period of time that molted hens were returning to production (third, fourth and fifth 4-week periods), it is not possible to attribute the improvements in quality to intermittent watering per se. as will be noted in Exp. 2. Experiment 2. The performance of pullets subjected to intermittent watering or feeding is summarized in Table 5. The intermittent feeding of O. S. U. W. L. pullets for two 2-hour periods daily tended to reduce their hen-day
Mort. % 11.1a ll.la 13.9a 19.5a Feed/ g. egg8 g2.69a 2.67a 2.55b 2.76a
egg production in comparison with the control group (70.5 vs. 66.7%). Patel and McGinnis (1970) observed no decline in egg production when limiting feeding time in a manner similar to that used in this study. Polin and Wolford (1972), however, observed that hens given two 2-hour meals daily laid 8% fewer eggs. Hen-day egg production of 70.5, 74.6 and 73.4% was recorded for the control, and the groups with water 15-minutes each hour, and five 15-minute watering periods, respectively. These differences were not statistically significant. Hens receiving 15-minutes of water each hour laid significantly heavier (P < .05) eggs (Table 5) than the control and the group with two 2-hour feeding periods. Average egg weight for the control and those with five 15-minute watering periods was 60.7 and 61.5 g., respectively. These values show that intermittent watering in this study did not have an adverse effect on average egg weight. Also in comparison with the control, average egg weight was not altered by intermittent feeding. Patel and McGinnis (1970) and Polin and
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Hen-day Avg. egg Wt. egg prod.3 wt.4 gain5 % g. g. Control 70.5ab 60.7b 699a 15-min. H 2 0/hr. 74.6a 63.1a 698a 15-min. H 2 0 (five times/day) 73.4ab 61.5ab 544b Two, 2-hr. feedings 66.7b 61.0b 498b Egg/ Feed/ Feed/ Treatment hen-day hen-day6 egg7 gggControl 42.29a 114.4a 162.7ab 15-min. H 2 0/hr. 46.78a 124.0a 167.4a 15-min. H 2 0 (five times/day) 44.80a 114.1ab 115.0b Two, 2-hr. feedings 40.27a 109.7b 166.6a 1 Values with differing lowercase superscripts are significantly different (P < .05). 2 Each treatment consisted of 12 replicates of three birds each. 3 Avg. of hen-day egg production for the ten 28-day periods. 4 Avg. of egg wt. for the ten 28-day periods. 'Avg. wt. gained per pullet during the 40-week experiment. 6 Total feed consumed/total number of hen-days for the 40-week experiment. 'Total feed consumed/total number of eggs laid during the 40-week experiment. 8 Total feed consumed/total g. of egg for the 40-week experiment. Treatment2
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INTERMITTENT WATERING AND FEEDING PROGRAMS
TABLE 6.—Effects
provided water 15-minutes each hour consumed 10 g. more feed per hen-day, laid heavier eggs (63.1 vs. 60.7 g.) and produced at a higher rate (74.6 vs. 70.5%) than did the control. Although not statistically significant, the five 15-minute watering periods and the intermittent feeding groups consumed 0.3 and 4.7 g., respectively, less feed per hen day than did the control group. Significant differences (P < .05) in feed conversion were observed in Exp. 2 (Table 5). Layers provided five 15-minute watering periods required 7.7, 12.7, and 11.6 g. less feed to produce an egg than the control, the 15-minutes water per hour and the intermittently fed groups, respectively. Providing five 15-minute watering periods resulted in significantly less (P < .05) feed consumed (0.14, 0.12 and 0.21 g., respectively) to produce a gram of egg than the other treatments. Hill (1969) utilizing a similar watering regime, also observed an improvement in feed efficiency. Table 6 summarizes the effects of treatment on distribution of egg size. Layers provided water for 15-minutes each hour tended to lay fewer medium and large eggs, and more extra-large and jumbo eggs. This finding corresponds with the significantly heavier average egg weight observed with this treatment. Upon periodic observation, it was noted that all intermittently watered birds first satisfied their thirst when the solenoid valve opened, and then began to actively consume feed. One of the advantages claimed for
of intermittent watering and feeding programs on egg size distribution—Exp. 2' Egg size
Treatment2
Peewee & small
Medium
Large
Extra-large
%
%
%
%
%
25.04a 34.68a
4.24a 8.06a
30.53a 26.75a (P < .05).
2.07a 2.80a
Control 4.04a 20.05ab 46.64a 15-min. H 2 0/hr. 1.33a 15.04b 40.91a 15-min. H 2 0 (five times/day) 1.33a 20.70ab 45.38a Two, 2-hr. feedings 1.71a 22.51a 46.24a 'Values with differing lowercase superscripts are significantly different 2 Each treatment consisted of 12 replicates of three birds each.
Jumbo
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Wolford (1972) observed lower egg weight when hens were provided with two 2-hour feeding periods per day; however, Harrison (1972) utilizing the same feeding regime, observed no difference in egg weight. Layers provided with two 2-hour feeding periods or five 15-minute watering periods gained significantly less weight (P < .05) during the 40-week lay period than the control or those with 15-minutes water per hour. This would indicate that a greater percentage of the feed consumed by the intermittently watered (five 15-minute periods per day) pullets was converted into eggs rather than weight gain. Mortality for the four treatments was not significantly different. However, mortality for the intermittently fed layers reached 19.5%. The high mortality for this group reduced the cumulative hen-housed egg production to 55.7%. The other three treatments all laid above 66% on a hen-housed basis. There were no statistically significant differences in egg mass produced, however, the groups provided water 15-minutes each hour or five times daily, respectively, produced 10 and 5.9% more egg mass per hen-day than did the control group (Table 5). These differences resulted from the higher hen-day egg production and average egg weight observed in both intermittently watered groups. Intermittent watering did not result in a significant reduction in feed intake in this experiment. On the contrary, those pullets
1878
R. J. SPILLER, R. W .
TABLE 7.—Specific gravity of eggs from intermittent water and feeding programs—Exp.
Treatment 2 Control 15-min. H 2 0 / h r . 15-min. H 2 0 (five times/day) Two, 2-hr. feedings
DORMINEY AND G. H .
2
Sp. Gr. Pd. 1 Pd. 5 Pd. 9 1.0816A 1.0801 A 1.0786A 1.0826A 1.0802A 1.0777A 1.0835A 1.0816A 1.0783A 1.0812A 1.0818A 1.0807A
1 Values with differing uppercase superscripts are significantly different (P < .01). 2 Each treatment consisted of 12 replicates of three birds each.
TABLE 8.—Haugh units of eggs from intermittent watering and feeding programs—Exp 2' Haugh Units Treatment 2 PdTl PdT~5 Pd79" Controls 84.7A 82.4A 76.5AB 15-min. H 2 0 / h r . 83.1A 80.6A 73.8B 15-min. H 2 0 (five times/day) 82.2A 79.4A 72.3B Two, 2-hr. feedings 83.3A 82.7A 78.6A 1 Values with differing uppercase superscripts are significantly different (P < .01). 2
Each treatment consisted of 12 replicates of three birds each.
findings would suggest that the significant effects observed in Exp. 1 (Tables 3 and 4) were due to hens molting and subsequently returning to production rather than the intermittent watering treatments. Experiment 3. The performance of the intermittently watered Babcock B-300 pullets is presented in Table 9. Pullets provided with three 15-minute watering periods per day gained significantly less (P < .05) weight during 36 weeks of lay than did all other treatments. When water was available for 15-minute periods each hour or five times daily, gains were not different from the control. This is contrary to the results observed in Exp. 2 (Table 5). The conflicting findings may be explained on the basis of strain differences. Differences in hen-day egg production were not significant; however, all three intermittently watered groups laid at a higher rate than the control. In both Exp. 2 and 3, pullets provided five 15-minute watering periods laid at a numerically higher rate than the controls. Hill (1969) reported a slight reduction in hen-day egg production when pullets were provided five 15-minute watering periods per day when initiated at 21 weeks of age. Strain differences may again account for the dissimilarity of results. Differences could also be explained by water trough length. In this study (Exp. 1-3), the water traveled only 216 cm. (85") before reaching the last cage in each row. Under commercial conditions where troughs may be 91.4 m. (300') or more in length, the duration of the watering periods might have to be extended to insure that the last cage in each row received an adequate supply of water. The differences on the effects of providing three 15-minute watering periods per day between Exp. 1 and 3 can best be explained by noting the time of initiation of the watering programs. In Exp. 1, the watering program began in the middle of the lay cycle resulting
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automatic feeders is that the movement of the chain or auger promotes consumption. Perhaps in this experiment, the water flow, activated each hour served the same function as the automatic feeder, causing an increased feed intake and ultimately a significantly higher average egg weight. No significant differences were observed for specific gravity (Table 7). There were no significant Haugh unit differences for the intermittently watered layers and the controls at any period (Table 8). This also was the case for the intermittently fed birds except for the 9th period where a significantly higher value (P < .01) was noted when compared with the restricted water treatments. This difference could possibly be due to the fact that the intermittently watered groups were laying at a higher rate than the intermittently fed group (74.6 and 73.4 vs. 66.7%). These
ARSCOTT
INTERMITTENT WATERING AND FEEDING PROGRAMS
1879
TABLE 9.—Performance of White Leghorn pullets subjected to intermittent watering—Exp. 3' Treatment2 Control 15-min. H 2 0/hr. 15-min. H 2 0 (five times/day) 15-min. H 2 0 (three times/day) Treatment
Hen-day egg prod.3 % 74.8a 76.1a 77.7a 77.9a Egg/ hen-day5
Avg. egg wt. g. 57.2a 56.7a 57.1a 54.6b Feed/ hen-day6
Wt. gain4 g. 623a 663a 628a 524b Feed/ egg7
§•
§•
8-
Mort. % 0.0b ll.la 2.8b 0.0b Feed/ g. egg8 §•
in a significant decline in egg production, and an apparent force molt in some hens. In Exp. 3, the watering program was initiated prior to the onset of production, apparently allowing the pullets time to adapt to the watering regime. The most mortality, 11.1%, occurred in the group having water available 15-minutes each hour. Although this level proved significantly different, it is not excessively high. No mortality occurred in the control and three 15minute watering periods groups. The group provided three 15-minute watering periods per day consumed significantly less feed per hen-day than did the control and water 15 minutes each hour groups. The group provided five and three 15 minute watering periods daily consumed 97.3% and 95.5%, respectively, as much feed as the group with with water 15-minutes each hour, which consumed the same amount of feed per hen-day as did the control. Differences in feed consumed per egg were not statistically significant. The intermittently watered groups (15-minutes water each hour, five and
2.60a 2.57a 2.43a 2.50a
three 15-minute periods) required 98.6, 93.9 and 92.6% as much feed as the controls to produce an egg. These same groups required 98.8, 93.5 and 96.2% as much feed, respectively, as the control group to produce a gram of egg. The pullets provided five 15-minute 62
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— - Three I5-Min. periods /day
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Five 15-Min. periods /day I5-Min. period each hour i
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3 4 5 6 7 28-DAY PERIOD
FIG. 2. Average egg weights of intermittently watered hens during nine 28-day experimental periods—Exp. 3.
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Control 42.8a Ilia 148a 15-min. H 2 0/hr. 43.1a 111a 146a 15-min. H 2 0 (five times/day) 44.4a 108ab 139a 15-min. H 2 0 (three times/day) 42.6a 106b 137a •Values with differing lowercase superscripts are significantly different (P < .05). 2 Each group contained two replicates of 18 birds each. 'Total number of eggs laid/total number of hen-days for the 36-week experiment. 4 Avg. wt. gained per hen during the 36-week experiment. 5 Total g. of egg produced/total number of hen-days for the 36-week experiment. 6 Total feed consumed/total number of hen-days for the 36-week experiment. 7 Total feed consumed/total number of eggs laid during the 36-week experiment. 8 Total feed consumed/total g. of eggs for the 36-week experiment.
1880
R. J. SPILLER, R. W. DORMINEY AND G. H. ARSCOTT
TABLE 10.—Egg size distribution of Babcock B-300 layers as affected by intermittent watering—Exp. 3' Egg Size Treatment2
Peewee & small
Medium
Large
Extra-large
%
%
%
%
Control 8.61a 38.49a 9.82a 42.70a 15-min. H 2 0/hr. 12.55a 31.63a 6.95a 48.44a 15-min. H 2 0 (five times/day) 9.46a 36.44a 42.48a 11.63a 15-min. H 2 0 (three times/day) 20.26a 41.46a 31.25b 6.91a 'Values with differing lowercase superscripts are significantly different (P < .05). 2 Each treatment consisted of two replicates of 18 birds each.
The egg size distribution is shown in Table 10. Pullets watered three times daily laid significantly fewer large eggs and tended to lay more peewee, small and medium eggs, and fewer extra-large eggs. The other two intermittent watering regimes did not alter egg size distribution.
% 0.40a 0.44a 0.00a 0.14a
There were no significant differences in the moisture content of the fecal samples. The average dry matter content of the feces from the control, and the three or five 15minute watering periods was 28.5, 29.0 and 24.2%, respectively. Since the laying facilities were not temperature controlled, the birds were exposed to temperatures in excess of 26.7° C. on many occasions. Periodically maximum ambient temperatures in excess of 32.2° C. were recorded. However, at no time did the intermittently watered layers appear to be more heat stressed than the control group. REFERENCES Arscott, G. H., and P. E. Bernier, 1961. Application of specific gravity to the determination of eggshell thickness. In: Agricultural Science Laboratory Excercises for High School Students. Agricultural Science No. 2. School of Agriculture, Oregon State University. Harrison, P. C , 1972. Two feeding periods best in limiting time feeding. Poultry Digest, 31: 148. Hill, A. T., 1969. Phase watering for laying stock. Can. Poultry Rev. 93: 38. Hill, A. T., and J. F. Richards, 1969. Consequences of limiting cage layer watering time. Poultry Sci. 48: 1819. Johnston, G. W., M. H. Swanson and C. A. Salverson, 1973. Feed restriction through three lay cycles. Poultry Institute Proceedings, Univ. Cal. Agric. Ext. pp. 8-13. Knight, H. F., 1970. Controlled water systems for cages. Poultry Digest, 29: 84-85.
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watering periods per day tended to produce eggs more efficiently, concurring with the findings in Exp. 2. A significant difference (P < .05) was observed in average egg weight. Figure 2 shows the average egg weights of the control and intermittently watered groups for each 4-week period. Pullets provided three 15minute watering periods per day consistently laid significantly (P < .05) smaller eggs than did birds in the other three treatments. The reduction in average egg weight in the first five periods is undesirable because of the large number of peewee, small and medium eggs. However, a reduction in egg size may be desirable after the sixth period when a larger percentage of the eggs laid are large, extra-large and jumbo. Producers selling to a wholesaler, receiving little or no premium for extra-large over large and only a small premium for jumbos, may benefit economically from reductions in the numbers of extra-large and jumbo eggs, and in feed intake as a result of this intermittent watering regime.
Jumbo
INTERMITTENT WATERING AND FEEDING PROGRAMS
Maxwell, B. J., and J. B. Lyle, 1957. Restricted water for wet dropping prevention. Poultry Sci. 36: 921922. McGinnis,J.,and P. R. Patel, 1971. Time-limit feeding. Poultry Digest, 33: 253. Patel, P. R., and J. McGinnis, 1970. Effect of restricting feeding time on feed consumption, egg production, and body weight gain of Leghorn pullets. Poultry Sci. 49: 1425. Polin, D., and J. H. Wolford, 1972. The effect of
1881
meal-eating on egg production and body weight of White Leghorn chickens. Poultry Sci. 51:1109-1118. Salverson, C. A., 1959. Water restriction for layers. Pacific Poultryman, 65(21): 58-59. Steel, R. G. D., and J. H. Torrie, 1960. Principles and Procedures of Statistics. McGraw Hill Co. Inc., New York, New York. Wilson, H. R., C. F. Wright, R. W. Dorminey and I. E. Jones, 1965. Water restriction for caged layers. Sunshine State Agri. Res. Rep. 10(4): 11.
SARDUL S. GURAYA AND R. K. CHALANA
Department of Zoology, College of Basic Sciences & Humanities, Punjab Agricultural University, Punjab, India (Received for publication January 29, 1976)
ABSTRACT A histochemical study has been made of seasonal fluctuations in the follicular atresia and interstitial gland tissue with the ovarian cycles of the house sparrow (Passer domesticus). The atresia of primordial oocytes forms the predominant feature of the quiescentwinter ovary. The building up of interstitial gland tissue of thecal origin, which precedes the breeding activity, is closely related to the atresia of previtellogenic follicles of variable sizes. Interstitial gland cells which accumulate lipid droplets consisting of cholesterol, and/or its esters, triglycerides and some phospholipids, are the steroid secretors. The possible functional significance of different-sized follicular atresia in relation to follicular growth and breeding activity is discussed. POULTRY SCIENCE 55: 1881-1885, 1976
INTRODUCTION
A
S in other vertebrates (Guraya, 1973), follicular atresia also forms a conspicuous feature of the avian ovary, which has been distinguished into different types depending upon the stepwise size gradation at which the follicles become atretic (Kern, 1972; Erpino, 1973). But the physiological significance of different-sized atretic follicles is poorly understood during the reproductive cycle. Using histological and histochemical techniques, the present study on the ovary of house sparrow (Passer domesticus) was undertaken to determine the nature of relationships between the follicular growth and atresia and building up of interstitial gland tissue throughout the year. The results of
this study will form the basis for future experimental studies on the induction of follicular atresia and possible secretory role of atretic follicles. In the previous studies, very little attention has been paid to the atresia of primordial follicles, which is also investigated here. MATERIAL AND METHODS Three to five female specimens of house sparrows were collected at weekly intervals throughout the year. The fixatives used for the histochemistry of lipids included formaldehyde-calcium and weak Bouin's solution. After fixation, the material was postchromed in dichromate-calcium and embedded in gelatin. Frozen gelatin sections were
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Histochemical Observations on the Seasonal Fluctuations in the Follicular Atresia and Interstitial Gland Tissue in the House Sparrow Ovary