Comparison of the growth performances and carcass characteristics of three commercial broiler chicks in Iran in different nutritional condition

An investigation was carried out to evaluate growth performance and carcass characteristics of three commercial broiler strain ( A, B, C ), during four husbandry period in randomized complete block design with three treatment include stains and four block based on nutrition program include four phasing diets, high energy and high protein diets, pellet from diets and low energy and low protein diets. Husbandry conditions including environmental and managmental factors, were the same for three strains during each experimental periods.
The traits under consideration were daily body weight gain, daily feed intake, feed conversion ratio, means of live body weight, index of production, livability, carcass percentage, percent of breast, thigh and abdominal fat in end of 42th days of age. Statistical analysis of performance criteria showed that difference of daily weight gain in 42 days among of strain was significant and B had highest and C had lowest means of daily weight gain (P