• Korean Journal of Poultry Science
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• v.21 no.4
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• pp.257-266
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• 1994

Three protein feeding systems for egg-type pullets involving conventional step-down protein 18-15-12%), step-up protein(12-15-18%) and single-stage low protein (13-13-13%) with an iso-energy level of 2,900 ME kcal /kg were compared to examine the effect on pullet growth and subsequent laying performance. During the growing period, pullets subjected to the step-up and single-stage low protein feeding systems were lighter in body weight and consumed less feed and netabolizable energy than those on the conventional step-down protein feeding system(P<0.05). 3ut the pullets on the step-up protein diet consumed more protein, and those on the single-stage low protein diet consumed less protein than those on the step-down protein diet(P<0.05). Also, he feed cost was less in pullets on the single-stage low protein diet than in those on the other systems(P<0.05). During the laying period, sexual maturity was later in hens reared on the step-up and single-stage low protein diets than in those on the step-down protein diet(P<0.05), however, average hen-day egg production and egg weight were not significantly affected by the protein feeding systems in the growing period. Daily feed intake and feed required per egg were significantly reduced in hens on the single-stage low protein diet compared to those on conventional protein feeding system(P<0.05). It was concluded that the 13% single-stage low protein feeding system produced smaller pullets with less feed, energy, protein, and feed cost during the growing period, and hens reared on that system consumed less feed during the laying period without any impairment of production compared to the conventional rearing system.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.657-664
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• 1997

432 Babcock ISA white leghorn pullets reared for 8 weeks on a standard managemental conditions were exposed to feed/nutrient and light restrictions from 9 to 20 weeks of age. Four feeding regimes i. e. 100, 85 or 70 percent of the recommended allowance and low energy (2,500 Kcal/kg) low protein (13% CP) ration were fed each in the three light regimes i. e. (A) Natural day light starting from 13.24 hr/day at 8 weeks of age and ending 10.41 hr/day at the end of 20 weeks; (B) Constant 11 hr/day light and (C) starting with 13 hr/day at 8 weeks and decreasing @ 20 min/week till 20 weeks of age. At the age of 20 weeks all the birds were shifted to separate cages under uniform lighting feeding and management. During the 21st week light was increased to 12 hr a day and thereafter with an increase of 30 min per week, increased to 16 hr a day at the age of 29 weeks. From 20 weeks onward till 72 week age, all the birds were offered commercial layer rations ad libitum, prepared according to climatic conditions. The results of the study revealed that birds reared under natural and constant light had higher weights than decreasing light, yet they could not out perform during production period. The effect of feed and nutrient restriction, on the other hand, was found significant during rearing as well as production period. The birds exposed to higher level of feed and those exposed to nutrient restriction were lighter in weight. The 100% fed birds laid their first egg at an early age. However, those reared on 85% of the recommendation excelled all other groups in terms of produced number of eggs, egg mass, hen housed and hen day production and net returns.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.11a
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• pp.97-98
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• 2003

This experiment was conducted to investigate the effect of restricted feeding to pullet on growth and laying Performance, egg qualify and endocrine Profile in brown layers. 1,080 brown-layer chicks divided to three diet treatments, conventional diet and two restricted diets, for 70 weeks. Conventional diets(C) was formulated by NRC recommendation, and one of restricted diet started from seven to seventeen week of age(T1), and another started from twelve to seventeen(T2) with adjusted eighty percentage amount of conventional diet. Body weight decreased with starting restriction of feeding comparing to the C(P＜0.05), but reached to similar weight in all treatments at twenty week regardless restriction. All of birds started to lay egg around 1,400 to 1,450gram of body weight though the age was in order of C, T2 and T1. Overall e99 Production was the highest in T1 (P＜0.05) and there were not difference in C and T2. Average egg weight also showed similar to the tendency of egg production. Feed intake was higher in T1 during maximum production(P＜0.05), but there were not difference in all treatments after the peak. Overall feed conversion ratio improved in T1 compared to C and T1(p＜0.05). Restriction feeding in rearing period could be beneficial to improve egg productivity and to decrease feed cost.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.343-354
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• 2008

The objective of this study was to investigate the effect of restricted feeding to pullet on growth and endocrine profile in layers(Isa brown). One thousand eighty brown-layer chicks were divided into three treatments; conventional feeding(ad libitum) and two restricted feedings(80% of conventional diet) for 70 weeks. One of restricted feeding started from seven to seventeen weeks of age, and the other started from twelve to seventeen weeks of age. Diets were formulated by NRC(1994) recommendation. Body weight and feed intake were measured every two weeks, and body composition and organ weight analyzed every week in rearing period and every eight weeks in laying period. Blood was collected at weighing body weight and was analyzed for the concentration of insulin-like growth factor-Ⅰand estradiol. Body weight and feed intake decreased as restriction of feeding begins comparing to ad libitum group(P<0.05), but reached to similar body weight and feed intake at 20 wk of age regardless of restriction. There were no significant differences in development of digestive tract and attached organs among the treatment groups. During rearing period, however, they were slightly higher in restricted group which was low in body weight. In terms of body composition, fat contents of restricted group were significantly lower(P<0.05) than that of ad libitum group around 1,000 grams of body weight. High concentration of IGF-Ⅰwas observed.