Crescimento e deposio de nutrientes nos rgos de frangos de corte de duas linhagens comerciais

Abstract

This work was carried out with the objective of studying the growth profile and the nutrients deposition on organs (heart, liver, gizzard, intestine and proventricle) of male and female broiler chickens from Ross and Cobb lineages. It was used 1,920 chicks at the age of one day placed in experimental shed boxes on the floor. The experimental design was completely randomized in a 2 × 2 factorial model composed of 2 sexes (mates and females) and two strains with 4 repetitions of 120 broilers each. The broilers were fed formulated diets to supply the nutrient requirements according to each breeding phase. After 24 hours of fasting, the broilers were weighed and slaughtered (1 to 56 days) every week. The weight and components of the organs (water, ash, protein and fat) were weekly obtained, with parameters estimated by the equation of Gompertz and the growth rates were determined by the derived of the equations. There was no influence of the strains on the deposition of nutrients on the heart. Ross chicks were more precocious on growth and on the deposition of water and ashes in the liver, therefore it presents a greater metabolic activity in digestion and nutrient synthesis. Cobb strain was more precocious in the development of the intestine and the growth and deposition of nutrients on the proventricle. Males are more precocious than females on the growth rate and on the protein, fat and water deposition in the gizzard.