Two trials were conducted to study the effect of multi-steps phase-feeding (PF) program on growth performance of broiler chickens from 1 to 24 and 1 to 39 d of age. The control group was the nutrient recommendation of Aviagen (2019) with a three-step PF program (1-10, 11-24 and 25-39 d of age). In the first trial, the control group was compared with an eight-step PF program (PF8), and in the se...

abstract in this study 36 holstein bulls (initial bw of 345±61 kg) were randomly assigned to 6 dietary treatments, following a 3×2 factorial arrangement, with 3 concentrate level of fish oil (0, 1 and 2.1% of dm) and 2 levels of alfalfa hay versus corn silage (10 and 20 % of alfalfa hay forage) to investigate the effects of fish oil supplementation and ratio of alfalfa hay and corn silage in di...

this study was conducted to investigate the effects of different levels of zinc sulfate and chromium picolinate on the performance, immune response and meat quality of japanese quails under heat stress condition. the birds (n = 540; 7-d-old) were randomly assigned to 9 treatment groups consisting of 3 replicates of 20 birds each in a 3 × 3 factorial arrangement of treatments [zinc (0, 40, 80 mg...

this experiment was conducted using 172 male lambs of ghezel and mehraban breeds for two periods of 60 and 80 days. two systems of fattening were studied. the first group of lambs entered feedlot boxes immediately after weaning (spring) but the second group being fed on pasture, entered the experiment approximately 4 months later (autumn). fattening periods were 60 and 80 days. the average wean...

the aim of this study was to evaluate the effects of three lighting programs on immune system and performance of broiler chickens. a total of 288 seven day-old male broiler chicks (ross-308) were randomly distributed between three treatments. each group was housed in the separated room with eight pen and 12-birds per pen. the management conditions were similar for all treatments throughout the ...

this experiment was conducted to evaluate the effect of different levels of crude protein and threonine on performance, carcass characteristics and immune system of broiler chickens during starter (7-24) and grower (25-42) periods. a total of 288 male broiler chicks of ross 308 strain were used in a completely randomized design with factorial arrangement (2×4) with three replicates in each trea...

In a 42-d experiment, 576 one-day-old Vencobb 308 broiler chicks were used to investigate the effects of lecithin extract (0.5 g/kg), choline chloride 60% (1 g/kg) and Bio choline (1 g/kg) in diets of moderate and high energy in a 4 × 2 factorial arrangement on performance and certain physiological traits in broiler chickens. The inclusion of Bio choline and lecithin extract in the diet signifi...

This study was conducted to investigate the effects of different levels of zinc sulfate and chromium picolinate on the performance, immune response and meat quality of Japanese quails under heat stress condition. The birds (n = 540; 7-d-old) were randomly assigned to 9 treatment groups consisting of 3 replicates of 20 birds each in a 3 × 3 factorial arrangement of treatments [zinc (0, 40, 80 mg...

this study was performed to determine the effect of copper on growth performance, blood metabolites and claw health in young holstein bulls in a humid area in north of iran. one hundred and two young holstein bulls (initial body weight= 377.3±17.1 kg) were randomly allocated to two treatments in a completely randomized design for 56 days. the treatment groups received: (1) the basal diet of no ...