Effects of dietary supplemental antioxidants (selenium and vitamin C), triiodothyronine hormone and iodine on performance, nutrients retention and relative organ weights in broilers exposed to cold conditions (15 degrees C).

摘要

This study was carried out to determine the effects of antioxidants (selenium and vitamin C), triiodothyronine hormone and iodine supplements on feed intake (FI), body weight gain (BWG), feed conversion ratio, mortality, crude nutrients retention and relative organ weights of broilers exposed to cold conditioning (15 degrees C). 150 day-old Ross 308 broiler chicks were randomized into 1 control and 4 treated groups each containing 30 birds and each experimental group comprised 3 replicates of 10 birds. The experimental groups were: Group I (control group), no supplement in the diet; Group II, selenium (Se, 1 mg/kg) + iodine (I, 2 mg/kg) in the diet; Group III, Se (1 mg/kg) + triiodothyronine (T3) hormone (1 mg/kg); Group IV, vitamin C (Vit C, 250 mg/kg) +I (2 mg/kg) and Group V, Vit C (250 mg/kg) + T3 hormone (1 mg/kg). It was shown that BWG and FI of Group IV at 15-40 days were significantly better in comparison with the control group. Crude protein retentions of Groups II, IV and V were significantly higher than the control group (P<0.05). Relative heart weights were significantly increased by dietary supplementation of Vit C + T3 in Group V (P<0.05). This effect was connected with dietary T3 supplementation. Relative thyroid weights were significantly higher in the control group than in treated groups (P<0.01). In conclusion, antioxidant dietary supplements have benefits during cold conditioning in broilers. Dietary vitamin C combined to I and T3 was found to be more effective in comparison to dietary Se plus I or T3.