Directory UMM :Data Elmu:jurnal:A:Animal Feed Science and Technology:Vol85.Issue3-4.Jun2000:
Animal Feed Science and Technology
85 (2000) 171±181
The use of step-down and modi®ed constant
protein feeding systems in developing
pullets reared in hot climates
Ahmed S. Hussein*
Department of Animal Production, Faculty of Agricultural Sciences, United Arab Emirates University,
P.O. Box 17555, Al-Ain, United Arab Emirates
Received 20 October 1999; received in revised form 16 February 2000; accepted 13 April 2000
Abstract
The effect of using varied levels of dietary protein with high energy levels in rearing diets on
pullet development and on subsequent layer performance in hot climates, was studied using 160
Lohmann White Leghorn pullets. Five replicate groups of 16 pullets, 1 day of age were randomly
assigned to each of two series of rearing diets. Pullets in both treatments were fed a 190 g crude
protein (CP)/kg starter diet in the ®rst week. Dietary protein level series used during Weeks 2±6, 7±
14, and 15±18 were 190, 160, and 135 g CP/kg, respectively, for the decreasing protein series
treatments and 160, 160, and 135 g CP/kg, respectively, for the semi-constant series. Energy level
used during the rearing period in all diets was 12.55 MJ AME/kg. Pullets were reared under a
natural cyclic hot temperature ranging as low as 278C measured at 07:00 hours and as high as 348C
measured at 13:00 hours. At the beginning of Week 19, pullets were transferred to laying cages and
fed two isocaloric layer diets for 20 weeks. Diet 1 used 190 g CP/kg and 4 g methionine/kg and Diet
2 used 160 g CP/kg and 3.4 g methionine/kg. Each diet was fed to half of the pullets within each
rearing treatment program. During the rearing period, body weight of pullets in both treatment
programs was similar, as was feed intake during Weeks 7±14 and 15±18. However, pullets fed diets
with 160 g CP/kg had signi®cantly (p
85 (2000) 171±181
The use of step-down and modi®ed constant
protein feeding systems in developing
pullets reared in hot climates
Ahmed S. Hussein*
Department of Animal Production, Faculty of Agricultural Sciences, United Arab Emirates University,
P.O. Box 17555, Al-Ain, United Arab Emirates
Received 20 October 1999; received in revised form 16 February 2000; accepted 13 April 2000
Abstract
The effect of using varied levels of dietary protein with high energy levels in rearing diets on
pullet development and on subsequent layer performance in hot climates, was studied using 160
Lohmann White Leghorn pullets. Five replicate groups of 16 pullets, 1 day of age were randomly
assigned to each of two series of rearing diets. Pullets in both treatments were fed a 190 g crude
protein (CP)/kg starter diet in the ®rst week. Dietary protein level series used during Weeks 2±6, 7±
14, and 15±18 were 190, 160, and 135 g CP/kg, respectively, for the decreasing protein series
treatments and 160, 160, and 135 g CP/kg, respectively, for the semi-constant series. Energy level
used during the rearing period in all diets was 12.55 MJ AME/kg. Pullets were reared under a
natural cyclic hot temperature ranging as low as 278C measured at 07:00 hours and as high as 348C
measured at 13:00 hours. At the beginning of Week 19, pullets were transferred to laying cages and
fed two isocaloric layer diets for 20 weeks. Diet 1 used 190 g CP/kg and 4 g methionine/kg and Diet
2 used 160 g CP/kg and 3.4 g methionine/kg. Each diet was fed to half of the pullets within each
rearing treatment program. During the rearing period, body weight of pullets in both treatment
programs was similar, as was feed intake during Weeks 7±14 and 15±18. However, pullets fed diets
with 160 g CP/kg had signi®cantly (p