THE INFLUENCE OF GENOTYPE, NUTRITION AND SEX ON CHEMICAL COMPOSITION OF MUSCLES IN BROILER CHICKENS

Adela Marcu, I. Vacaru-Opriş, A. Marcu, Lucia Dănăilă, Gabi Dumitrescu, Marioara Nicula, B. Kelciov

Abstract
In this paper was studied the influence of sex and nutrition on the meat chemical composition of breast, thighs and drumsticks, at different broiler genotypes. The biological material was represented by broilers: "Cobb-500" (Lc), "Hybro PN+"(L1 with variants V1, V2, V3) and "Hubbard F15" (L2 with variants V1, V2, V3), reared 42 days in identical microclimate conditions.The recipes of compound feed used had different levels of energy and protein: standard at Lc, L1V1 and L2V1; with 10% higher at L1V2 and L2V2; with 10% lower at L1V3 and L2V3. After slaughter, from each batch and variant were taken 10 carcasses (five per sex) and was determined the chemical composition of meat (water, dry matter, protein, lipids and ash), using STAS methods. For analysis of variance was used Mann Whitney test. The lipids content in meat showed the biggest variation between muscles analyzed, with minimum values in the breast and maximum values in thighs. In all cases, it was found that, males had a lower quantity of lipids and a higher quantity of proteins, compared to females.The results showed that the sex had significant influence on the lipids content from thighs and breast. The statistical differences between the three variants in the L1 and L2 batches, support the claim that the content of protein and lipids in the examined muscles was influenced by protein-energy levels of the feeding. The genotype has influenced content of proteins and lipids from breast, with statistical differences (p≤0.05) between Lc and L2.

Key words: broiler chicken, chemical composition of muscle, genotype, nutrition, sex