ABSTRACT
The variation in cloacal temperature, body weight loss and expression of the 70 kDa heat shock protein (Hsp70) in three naked neck broiler genotypes during heat stress were studied. Twelve birds of each genotype (Na/Na, Na/na and na/na) were reared to market weight (approximately 2.1kg) at thermoneutral temperature. Six birds from each group served as controls and the remaining six underwent gradual heat stress (from 28oC to 36oC). Cloacal temperature and body weight were measured before and after exposure to heat. Liver samples were collected and Hsp70 levels were quantified using western blotting with monoclonal anti-chicken Hsp70 antibody. Heterozygous (Na/na) birds had a significantly lower cloacal temperature variation and less body weight loss during heat stress than the other genotypes. There was no significant difference in the Hsp70 levels among the genotypes. Heterozygous birds (Na/na) appeared to have a slight advantage over the other genotypes during gradual heat stress, perhaps because of a heterotic effect
Subject(s)
Animals , Genes , Heat Stress Disorders , Poultry , ProteinsABSTRACT
1. Diets containing different amounts of an amino acid mixture were tested in terms of egg production and layings by Ceratitis capitata. The amino acid composition of the diet was identical to that of casein. The other components of the diet were: 1.0g agar, 0.8g of saalt mixture, 0.8 g of a vitamin mixture, 1.6g corn oil, 0.2g Tween 80,05 ml propionic acid, 90 ml distilled water and 0.5 ml of a 20% alcohol solution of nipagin. Diets containing 0.4, 0.8, 1.3, 1.6 and 2.0g of an amino acid mixture per 100 ml diet and an amino acid-free control diet were used. The diets were made isocaloric by adding 12.4, 12.0, 11.6, 11.2 and 10.8g sucrose, respectively. 2. The diet containing 1.2g amino acids proved to be the best, leading to 6.84 egg layings per female per day and to production of 7.72 eggs per female per day