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Feed Consumption of Egg Strain Pullets at Onset of Lay
Feed Consumption of Egg Strain Pullets at Onset of Lay YISHENG BAI and MILTON L. SXJNDE Departments of Nutritional and Poultry Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706 (Received for publication June 7, 1990)
1991 Poultry Science 70:766-769 INTRODUCTION
It was suspected that strains of commercial egg-type pullets differed in feed consumption when they were coming into egg production. In addition, reports differ regarding feed consumption patterns of pullets prior to and after the first oviposition. In the first of experiments, Foster (1968) reported a decrease in feed consumption from 13 to 2 days prior to the first egg, and the lowest feed intake was on the 2 days before the first egg. In the second experiment, he noticed that feed consumption decreased starting from 18 days prior to the first oviposition, but the data after onset of production were not collected. In a study of feed consumption and calcium intake associated with the pullet's first egg, Meyer et al. (1970) found that feed consumption definitely decreased as pullets approached their first oviposition, and the lowest feed consumption took place on the day after the first egg. Scott and Balnave (1989) reported a noticeable drop in feed intake at sexual maturity. But Sloan and Harms (1989) reported an increase in feed intake on the first day of oviposition compared with the average of the 5 previous days. The purpose of the current experiment was to
determine the feed consumption patterns of egg type pullets near the date of the first egg. MATERIALS AND METHODS
Commercial egg-type pullets (April hatch) were obtained from a commercial breeder and raised in cages. At 18 wk, 264 pullets (66 per strain) were randomly selected and placed into individual laying cages. The experiment was divided into 4-wk periods and was conducted from 19 to 30 wk of age. A corn and soybean meal diet (Table 1) was fed to all birds, and daily individual feed intakes were recorded throughout the experimental period. Starting at 19 wk of age, 15 h of artificial light were provided daily. Individual egg production was recorded daily and is expressed as percentage of hen-day egg production. Egg weights were obtained from consecutive 2-day collections at 25 and 30 wk of age. Body weights were obtained at the end of 18 and 30 wk. Feed consumption data (during 10 days prior to and 10 days after the first oviposition) were sorted and calculated according to each individual pullet's egg production record for each strain and for the combination of the four strains. Repeated Measures Analysis of Vari-
766
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ABSTRACT An experiment was conducted to investigate the performance of four strains of commercial egg type pullets (A, B, C, and D) from 19 to 30 wk of age. The feed consumption differences during this period as well as feed consumption patterns 10 days prior to and after the first oviposition were of special interest Two hundred and sixty-four birds (66 birds per strain) were fed a diet formulated to contain 2,750 kcal/kg ME, 17% CP, and 3.4% calcium. Results show that the average age to the first egg and percentage of hen-day egg production were not significantly different among the four strains of birds. However, egg weights of Strain A and C birds were significantly heavier than those of the Strain B and D birds. The birds from Strains B and D had significantly lower body weight than Strain A birds at the end of 18 wk, but body weights were not significantly different at the end of 30 wk. Feed intake per bird per day of pullets from Strains A and C was generally higher than that of those from Strains B and D in the first and second 4-wk period. Some of the consumption differences were significant. Feed intake in the third period (27 to 30 wk) was similar for the four strains of birds. Although different strains showed different feed consumption patterns around the first oviposition, all strains showed a drop on the day of the first oviposition. When the strains were combined, feed consumption was lower on that day than during the 8 days prior to the first oviposition. (Key words: pullet, strain, feed consumption, oviposition, performance)
767
FEED CONSUMPTION PATTERNS IN EGG STRAIN PULLETS TABLE 1. Feed composition Ingredient
TABLE 2. Body weight (g) of four strains of pullets at 18 and 30 wk of age
Percentage 58.22 25.80 3.00 1.58 7.70 2.13 .07 1.00 .50
Corn Soybean meal (44% CP) Alfalfa meal (17% CP) Dicalcium phosphate Limestone Lard Methionine Premix1 Salt
Calculated analysis ME, kcal/kg CP, % Ca, % Available P, % Met and Cys, % Lys, %
2,750.00 17.00 3.40 .43 .63 .93
ance of the SAS Institute (1985) was used to test differences in feed intake patterns during this period; 10 days before the first egg; or the day of the first egg plus following 10 days. The rest of data were subjected to an analysis of variance, using the General Linear Models procedure of the SAS Institute (1985). All means were separated for significance by the Least Significant Difference method. Percentage of hen-day egg production was transformed using an arc sine transformation (arc sine square root of percentage of hen-day egg production). However, only the percentage values are reported for ease of data interpretation (SAS Institute, 1985). The statistical significance was P<.05. RESULTS AND DISCUSSION
At 18 wk of age, body weights of pullets from Strain A were significantly heavier than those from Strains B and D, and those from Strain C were intermediate (Table 2). However, at the end of the experiment (30 wk), body weights of birds from the four strains were similar. This shows that although strains may have similar weights at maximum egg production, genetic differences still exist in their growth patterns. Percentage of hen-day egg production for the three periods, and pullet
18 wk
30 wk
A B C D Pooled SEM
U22a l,169 b U01ab l,172 b 15.5
1,673 1,658 1,663 1,666 19.9
a,b Values within the same column with no common superscript are significantly different (P<05).
ages at the first egg were similar among the four strains of birds (Table 3). Strain A pullets produced significantly heavier eggs than Strains B or D at 25 wk of age. By the end of the experiment (30 wk), the birds from Strains A and C laid significantly heavier eggs than those from Strains B and D (Table 4). Except for the lighter body weights at 18 wk of age, other parameters measured are within the range recommended by the breeding company management guide (Shaver Poultry Breeding Farms Limited, 1985). From 19 to 22 wk, the birds from Strains A and C consumed significantly more feed than those from Strain B (Table 5). Pullets from Strain C consumed significantly more feed than those from Strain D. Li Period 2 (23 to 26 wk), feed intake of the birds from Strains B and D was significantly less than those from Strain A, but there were no differences between Strain A and C birds. There was no significant difference in feed intake for the four strains of birds from 27 to 30 wk. It cannot be concluded that the lower feed intake of birds of Strains B and D was due to lower body weight at 18 wk of age or smaller egg size than Strain A and C birds. There were no differences in feed intake and body weight among the four strains of birds at 30 wk of age, and egg weight differences still existed. Another year-long project using the same strains showed that the egg weight was constantly lower for Strains B and D compared with that of Strains A and C, regardless of body weight or feed intake (data not shown). This indicated that the egg weight difference between Strains A and C and Strains B and D was due to genetic selection. The average feed consumption patterns of the four strains of pullets 10 days prior to and 10 days after the first oviposition are shown in
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
'Vitamin and trace mineral premix ^provide per Y1UU111U UUU \XVSX U l U l C i a i pit r_ "iet; vitamin A, 12,000 IU; vitamin ' • D - 3 , •1,500 kilogram of"diet; IU; vitamin E,!, 25 mg; vitamin K, 1 mg; choline, 396 mg; lg; biotin, .11 mg; paiuuuiciw; auiu, 2.86 x.ou iug; niacin, 3.63 mg; pantothenic acid, mg; riboflavin, 3 me: mg; foliacin. foliacin, .45 me: mg; Mn. Mn, 41.33 me: mg; Zn, Zn. 32.21 mg.
Strain
768
BAI AND SUNDE TABLE 3. Percentage of hen-day egg production and age at the first egg of four strains of pullets 23 to 26 wk
19 to 22 wk
Strain
27 to 30 wk
Age at first egg
93.3 92.8 91.2 93.5 1.5
(day) 153.3 155.5 153.1 154.2 1.2
(m<\ A B C D Pooled SEM
12.0 8.4 11.6 11.2 1.5
75.8 74.9 76.4 72.8 2.5
TABLE 4. Egg weight (g) of four strains of pullets at 25 and 30 wk of age 25 wk
30 wk
54.1* 52.1 b
58.4a 56. l b 57.6a 54.6C .5
•ftff*' 51.8° .4
a_c
Values within the same column with no common superscript are significantly different (P<05).
Figure 1. Feed intake of the pullets from Strain A dropped beginning 1 day prior to the onset of lay, and the lowest feed intake was on the day after the first egg. For the pullets from Strain B, feed intake dropped beginning 3 days prior to the first oviposition, and the day of the first egg and the following day were the lowest. The pullets from Strain C consumed the same amount of feed on the 2 days before and the day of the first egg, which were lower than the feed intake of the previous 4 days. Feed intake of pullets from Strain D began dropping 5 days prior to the first oviposition, and the lowest feed intake was on the day of the first egg. Feed intake during these 21 days fluctuated considerably from day to day, and by different strains, but there was a general pattern that increases prior to, decreases on,
TABLE 5. Feed consumption (grams per bird per day) of four strains of pullets in different periods Strain
19 to 23 wk
A B C D Pooled SEM
85* 81 e 86a 83* 1.0
23 to 26 wk a
106 102b 104ab 101b 1.2
27 to 30 wk 112 110 111 108 1.2
Values within the same column with no common superscript are significantly different (P<05).
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
Strain A B C D Pooled SEM
and then increases after the first egg. This finding somewhat agrees with Foster's (1968) report mat Brown Leghorn and Sussex pullets also showed different variation in feed consumption patterns around the first oviposition. There was evidence that the four strains of pullets had different feed intake patterns across the time (P<.01) during 10 days prior to and after the first oviposition. Although feed intake varied considerably, evidence was weak for difference in feed intake patterns 10 days prior to the first egg (P=.07). As for the feed intake patterns on the day of the first egg and the following 10 days, however, evidence was strong for an overall linear increase (P<01) and for an interceptor difference (P<01) with Strain C lower than Strains A, B, and D (P<.01, Figure 1). The average feed consumption pattern of the 264 pullets (as an egg-type breed) 10 days prior to and 10 days after the first oviposition is shown in Figure 2. Feed intake of the pullets dropped on the day of the first egg, which confirms the observations made by Foster (1968), Meyer et al. (1970), and Scott and Balnave (1989). However, the drop in feed intake was not as large as those reported by the above authors. In the present experiment, one would need to go back to Day 8 to find a day with lower feed consumption than the day of the first egg. Averages of feed intake 5 days
FEED CONSUMPTION PATTERNS IN EGG STRAIN PULUETS
769
Strain A Strain B Strain C 100
.*•
p v^
Strain D X.
**- P
M M
-10-9
-8-7-6-5-4-3-2-101234567
9 10
Days
FIGURE 2. Average daily feed intake of four strains of commercial egg pullets during 10 days prior to and after the first egg (Day 0).
before first egg, 5 days following the first egg, and at onset of lay are 92, 90, and 94 g per bird per day, respectively, by Sloan and Harms' (1989) calculation. Sloan and Harms (1989) reported that average feed consumption on the day of the first egg was 80 g, which was 6 g higher than that during the 5 days prior to and 4 g lower than that during the 5 days after the first egg. Combining the reported data and the present results, it was concluded mat egg strain pullets show a feed intake drop at onset of lay, but the extent of the decreases was different among strains. There is no known scientific reason for the drop in feed consumption around the day of the first oviposition at this time. The possible explanation for this drop must be due to the hormonal changes that occur during this critical period in a pullet's life, or the disturbance made by the development of the first egg, or the physical disruptiveness caused by the laying of the first egg.
ACKNOWLEDGMENT
The authors wish to thank the Shaver Poultry Breeding Farms Limited for partial support of this project. REFERENCES Foster, W. H., 1968. A fall in food consumption immediately prior to first egg. Br. Poult Sci. 47: 367-369. Meyer, G. B., S. W. Babcock, and M. L. Sunde, 1970. Decreased feed consumption and increased calcium intake associated with pullet's first egg. Poultry Sci. 49:1164-1169. SAS Institute, 1985. SAS® User's Guide: Statistics, Version 5 Edition. SAS Institute, Inc., Cary, NC. Scott, T. A., and D. Balnave, 1989. Self-selection feeding for pullets, part II. Poult Int (Dec.):22-26. Sloan, D. R., and R. H. Harms, 1989. Feed consumption patterns in Leghorn pullets at the onset of lay. Poultry Sci. 68(Suppl.):135.(Abstr.) Shaver Poultry Breeding Farms Limited, 1985. Shaver Starcross 288A Commercial Management Guide. Cambridge, Ontario, Canada.
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
FIGURE 1. Daily feed intake of four strains of commercial egg pullets during 10 days prior to and after the first egg (Day 0).
1991 Poultry Science 70:766-769 INTRODUCTION
It was suspected that strains of commercial egg-type pullets differed in feed consumption when they were coming into egg production. In addition, reports differ regarding feed consumption patterns of pullets prior to and after the first oviposition. In the first of experiments, Foster (1968) reported a decrease in feed consumption from 13 to 2 days prior to the first egg, and the lowest feed intake was on the 2 days before the first egg. In the second experiment, he noticed that feed consumption decreased starting from 18 days prior to the first oviposition, but the data after onset of production were not collected. In a study of feed consumption and calcium intake associated with the pullet's first egg, Meyer et al. (1970) found that feed consumption definitely decreased as pullets approached their first oviposition, and the lowest feed consumption took place on the day after the first egg. Scott and Balnave (1989) reported a noticeable drop in feed intake at sexual maturity. But Sloan and Harms (1989) reported an increase in feed intake on the first day of oviposition compared with the average of the 5 previous days. The purpose of the current experiment was to
determine the feed consumption patterns of egg type pullets near the date of the first egg. MATERIALS AND METHODS
Commercial egg-type pullets (April hatch) were obtained from a commercial breeder and raised in cages. At 18 wk, 264 pullets (66 per strain) were randomly selected and placed into individual laying cages. The experiment was divided into 4-wk periods and was conducted from 19 to 30 wk of age. A corn and soybean meal diet (Table 1) was fed to all birds, and daily individual feed intakes were recorded throughout the experimental period. Starting at 19 wk of age, 15 h of artificial light were provided daily. Individual egg production was recorded daily and is expressed as percentage of hen-day egg production. Egg weights were obtained from consecutive 2-day collections at 25 and 30 wk of age. Body weights were obtained at the end of 18 and 30 wk. Feed consumption data (during 10 days prior to and 10 days after the first oviposition) were sorted and calculated according to each individual pullet's egg production record for each strain and for the combination of the four strains. Repeated Measures Analysis of Vari-
766
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
ABSTRACT An experiment was conducted to investigate the performance of four strains of commercial egg type pullets (A, B, C, and D) from 19 to 30 wk of age. The feed consumption differences during this period as well as feed consumption patterns 10 days prior to and after the first oviposition were of special interest Two hundred and sixty-four birds (66 birds per strain) were fed a diet formulated to contain 2,750 kcal/kg ME, 17% CP, and 3.4% calcium. Results show that the average age to the first egg and percentage of hen-day egg production were not significantly different among the four strains of birds. However, egg weights of Strain A and C birds were significantly heavier than those of the Strain B and D birds. The birds from Strains B and D had significantly lower body weight than Strain A birds at the end of 18 wk, but body weights were not significantly different at the end of 30 wk. Feed intake per bird per day of pullets from Strains A and C was generally higher than that of those from Strains B and D in the first and second 4-wk period. Some of the consumption differences were significant. Feed intake in the third period (27 to 30 wk) was similar for the four strains of birds. Although different strains showed different feed consumption patterns around the first oviposition, all strains showed a drop on the day of the first oviposition. When the strains were combined, feed consumption was lower on that day than during the 8 days prior to the first oviposition. (Key words: pullet, strain, feed consumption, oviposition, performance)
767
FEED CONSUMPTION PATTERNS IN EGG STRAIN PULLETS TABLE 1. Feed composition Ingredient
TABLE 2. Body weight (g) of four strains of pullets at 18 and 30 wk of age
Percentage 58.22 25.80 3.00 1.58 7.70 2.13 .07 1.00 .50
Corn Soybean meal (44% CP) Alfalfa meal (17% CP) Dicalcium phosphate Limestone Lard Methionine Premix1 Salt
Calculated analysis ME, kcal/kg CP, % Ca, % Available P, % Met and Cys, % Lys, %
2,750.00 17.00 3.40 .43 .63 .93
ance of the SAS Institute (1985) was used to test differences in feed intake patterns during this period; 10 days before the first egg; or the day of the first egg plus following 10 days. The rest of data were subjected to an analysis of variance, using the General Linear Models procedure of the SAS Institute (1985). All means were separated for significance by the Least Significant Difference method. Percentage of hen-day egg production was transformed using an arc sine transformation (arc sine square root of percentage of hen-day egg production). However, only the percentage values are reported for ease of data interpretation (SAS Institute, 1985). The statistical significance was P<.05. RESULTS AND DISCUSSION
At 18 wk of age, body weights of pullets from Strain A were significantly heavier than those from Strains B and D, and those from Strain C were intermediate (Table 2). However, at the end of the experiment (30 wk), body weights of birds from the four strains were similar. This shows that although strains may have similar weights at maximum egg production, genetic differences still exist in their growth patterns. Percentage of hen-day egg production for the three periods, and pullet
18 wk
30 wk
A B C D Pooled SEM
U22a l,169 b U01ab l,172 b 15.5
1,673 1,658 1,663 1,666 19.9
a,b Values within the same column with no common superscript are significantly different (P<05).
ages at the first egg were similar among the four strains of birds (Table 3). Strain A pullets produced significantly heavier eggs than Strains B or D at 25 wk of age. By the end of the experiment (30 wk), the birds from Strains A and C laid significantly heavier eggs than those from Strains B and D (Table 4). Except for the lighter body weights at 18 wk of age, other parameters measured are within the range recommended by the breeding company management guide (Shaver Poultry Breeding Farms Limited, 1985). From 19 to 22 wk, the birds from Strains A and C consumed significantly more feed than those from Strain B (Table 5). Pullets from Strain C consumed significantly more feed than those from Strain D. Li Period 2 (23 to 26 wk), feed intake of the birds from Strains B and D was significantly less than those from Strain A, but there were no differences between Strain A and C birds. There was no significant difference in feed intake for the four strains of birds from 27 to 30 wk. It cannot be concluded that the lower feed intake of birds of Strains B and D was due to lower body weight at 18 wk of age or smaller egg size than Strain A and C birds. There were no differences in feed intake and body weight among the four strains of birds at 30 wk of age, and egg weight differences still existed. Another year-long project using the same strains showed that the egg weight was constantly lower for Strains B and D compared with that of Strains A and C, regardless of body weight or feed intake (data not shown). This indicated that the egg weight difference between Strains A and C and Strains B and D was due to genetic selection. The average feed consumption patterns of the four strains of pullets 10 days prior to and 10 days after the first oviposition are shown in
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
'Vitamin and trace mineral premix ^provide per Y1UU111U UUU \XVSX U l U l C i a i pit r_ "iet; vitamin A, 12,000 IU; vitamin ' • D - 3 , •1,500 kilogram of"diet; IU; vitamin E,!, 25 mg; vitamin K, 1 mg; choline, 396 mg; lg; biotin, .11 mg; paiuuuiciw; auiu, 2.86 x.ou iug; niacin, 3.63 mg; pantothenic acid, mg; riboflavin, 3 me: mg; foliacin. foliacin, .45 me: mg; Mn. Mn, 41.33 me: mg; Zn, Zn. 32.21 mg.
Strain
768
BAI AND SUNDE TABLE 3. Percentage of hen-day egg production and age at the first egg of four strains of pullets 23 to 26 wk
19 to 22 wk
Strain
27 to 30 wk
Age at first egg
93.3 92.8 91.2 93.5 1.5
(day) 153.3 155.5 153.1 154.2 1.2
(m<\ A B C D Pooled SEM
12.0 8.4 11.6 11.2 1.5
75.8 74.9 76.4 72.8 2.5
TABLE 4. Egg weight (g) of four strains of pullets at 25 and 30 wk of age 25 wk
30 wk
54.1* 52.1 b
58.4a 56. l b 57.6a 54.6C .5
•ftff*' 51.8° .4
a_c
Values within the same column with no common superscript are significantly different (P<05).
Figure 1. Feed intake of the pullets from Strain A dropped beginning 1 day prior to the onset of lay, and the lowest feed intake was on the day after the first egg. For the pullets from Strain B, feed intake dropped beginning 3 days prior to the first oviposition, and the day of the first egg and the following day were the lowest. The pullets from Strain C consumed the same amount of feed on the 2 days before and the day of the first egg, which were lower than the feed intake of the previous 4 days. Feed intake of pullets from Strain D began dropping 5 days prior to the first oviposition, and the lowest feed intake was on the day of the first egg. Feed intake during these 21 days fluctuated considerably from day to day, and by different strains, but there was a general pattern that increases prior to, decreases on,
TABLE 5. Feed consumption (grams per bird per day) of four strains of pullets in different periods Strain
19 to 23 wk
A B C D Pooled SEM
85* 81 e 86a 83* 1.0
23 to 26 wk a
106 102b 104ab 101b 1.2
27 to 30 wk 112 110 111 108 1.2
Values within the same column with no common superscript are significantly different (P<05).
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
Strain A B C D Pooled SEM
and then increases after the first egg. This finding somewhat agrees with Foster's (1968) report mat Brown Leghorn and Sussex pullets also showed different variation in feed consumption patterns around the first oviposition. There was evidence that the four strains of pullets had different feed intake patterns across the time (P<.01) during 10 days prior to and after the first oviposition. Although feed intake varied considerably, evidence was weak for difference in feed intake patterns 10 days prior to the first egg (P=.07). As for the feed intake patterns on the day of the first egg and the following 10 days, however, evidence was strong for an overall linear increase (P<01) and for an interceptor difference (P<01) with Strain C lower than Strains A, B, and D (P<.01, Figure 1). The average feed consumption pattern of the 264 pullets (as an egg-type breed) 10 days prior to and 10 days after the first oviposition is shown in Figure 2. Feed intake of the pullets dropped on the day of the first egg, which confirms the observations made by Foster (1968), Meyer et al. (1970), and Scott and Balnave (1989). However, the drop in feed intake was not as large as those reported by the above authors. In the present experiment, one would need to go back to Day 8 to find a day with lower feed consumption than the day of the first egg. Averages of feed intake 5 days
FEED CONSUMPTION PATTERNS IN EGG STRAIN PULUETS
769
Strain A Strain B Strain C 100
.*•
p v^
Strain D X.
**- P
M M
-10-9
-8-7-6-5-4-3-2-101234567
9 10
Days
FIGURE 2. Average daily feed intake of four strains of commercial egg pullets during 10 days prior to and after the first egg (Day 0).
before first egg, 5 days following the first egg, and at onset of lay are 92, 90, and 94 g per bird per day, respectively, by Sloan and Harms' (1989) calculation. Sloan and Harms (1989) reported that average feed consumption on the day of the first egg was 80 g, which was 6 g higher than that during the 5 days prior to and 4 g lower than that during the 5 days after the first egg. Combining the reported data and the present results, it was concluded mat egg strain pullets show a feed intake drop at onset of lay, but the extent of the decreases was different among strains. There is no known scientific reason for the drop in feed consumption around the day of the first oviposition at this time. The possible explanation for this drop must be due to the hormonal changes that occur during this critical period in a pullet's life, or the disturbance made by the development of the first egg, or the physical disruptiveness caused by the laying of the first egg.
ACKNOWLEDGMENT
The authors wish to thank the Shaver Poultry Breeding Farms Limited for partial support of this project. REFERENCES Foster, W. H., 1968. A fall in food consumption immediately prior to first egg. Br. Poult Sci. 47: 367-369. Meyer, G. B., S. W. Babcock, and M. L. Sunde, 1970. Decreased feed consumption and increased calcium intake associated with pullet's first egg. Poultry Sci. 49:1164-1169. SAS Institute, 1985. SAS® User's Guide: Statistics, Version 5 Edition. SAS Institute, Inc., Cary, NC. Scott, T. A., and D. Balnave, 1989. Self-selection feeding for pullets, part II. Poult Int (Dec.):22-26. Sloan, D. R., and R. H. Harms, 1989. Feed consumption patterns in Leghorn pullets at the onset of lay. Poultry Sci. 68(Suppl.):135.(Abstr.) Shaver Poultry Breeding Farms Limited, 1985. Shaver Starcross 288A Commercial Management Guide. Cambridge, Ontario, Canada.
Downloaded from http://ps.oxfordjournals.org/ by guest on May 4, 2015
FIGURE 1. Daily feed intake of four strains of commercial egg pullets during 10 days prior to and after the first egg (Day 0).