- - - Department of Animal Science, Ferdowsi University of Mashhad, International Branch, Mashhad, Iran.
- - - Department of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.

This experiment was conducted to study the effects of nucleotide supplementation on induced ascites and its effects on growth performance, blood metabolites, and expression of hypoxia-inducible factor ۱α (HIF-۱α) mRNA in Ross ۳۰۸ broiler chickens. A total of ۶۷۲ one-day-old Ross ۳۰۸ broiler chicks were allocated to eight treatments with two levels of common salt in drinking water (۰ and ۲ g/lit) and four dietary supplemental levels of nucleotides (۰, ۰.۵, ۱, and ۲ g/kg diet). Each treatment was included ۷ replicates of ۱۲ birds each. The experimental design was completely randomized in a factorial arrangement. In this study, ۰.۲% salt in drinking water induced ascites, decreased body weight (BW), and increased mortality, right ventricle (RV) weight as well as RV to total ventricles ratio (P < ۰.۰۵). Results showed that nucleotide levels of ۰.۰۵ and ۰.۱% significantly decreased RV weight and blood triiodothyronine (T۳) concentration on ۴۲ d. Interaction effects between salt and nucleotide supplement revealed that ۰.۱% nucleotide level in the salt group significantly reduced blood T۳ concentration in comparison with non-nucleotide supplemented and normal water group. Feed intake, weight gain, feed conversion ratio, carcass characteristics, and the expression of HIF-۱α mRNA in heart of broilers were not significantly affected by excess salt, nucleotide supplement, and their interaction. It was concluded that ۰.۵ g/kg dietary nucleotide supplementation decreased the ascites parameter of the RV/BW ratio in broiler chickens.

Ascites, Nucleotide, Broiler chicken, Gene expression