engleski

Effect of commercial mixtures on the quality of chicken carcasses and meat

This research was carried out on broilers of Ross 308 provenience. Broilers were divided into two groups and fed with mixtures of commercial composition ; starter and finisher diets that contained 22% and 20% of crude proteins, respectively. The 1st control group was fed with starter diets containing 2.5% of sunflower oil, 30% of soybean cake and 6% of fish flour, while the 2nd experimental group received starter diets with 3% of sunflower oil and 40% of soybean cake, without any fish flour. In the finisher diets, 1st chicken group got 3% of sunflower oil, 27.5% of soybean cake and 4% of fish flour, while the 2nd group had 4% of sunflower oil and 34.5% of soybean cake, also without fish flour. After 42 days of fattening, chickens were slaughtered and their carcasses were cut into main parts. Chickens of experimental group had lower values of live weight and carcass weight, but higher percentage of breasts and drumsticks with thighs. However, these differences were not statistically significant (P>0.05). The contents of proteins, fats and ashes in breast muscles were also not statistically different (P>0.05). Analysis of the amino acids content in breast muscles indicated no statistically significant differences between the two groups (P>0.05). Analysis of fatty acids profile in the lipids of breast muscles showed that the 1st group had statistically significant (P<0.01) higher percentage of palmitic acid (C 16:0) and significantly (P<0.05) higher percentage of docosahexaenoic acid (DHA, C22:6n3), when compared to the 2nd group. Furthermore, in comparison to the 2nd group, there were statistically significant (P<0.05) lower percentage of eicosenoic acid (C 20:1) and highly significant (P<0.01) higher percentage of linoleic acid (LA, C 18:2n6) and a-linolenic acid (α LNA, C18:3n3) observed in the 1st group. Higher percentage of palmitic and docosahexaenoic fatty acids in breast meat of the 1st group can be explained as a consequence of adding higher amounts of fish flour to diets. The PUFA n-6 / PUFA n-3 ratio was more favorable in meat of the 1st group than of the 2nd group. Although EPA and DHA were not present in diets given to the 2nd group, their occurrence in small amounts in breast muscles leads to a conclusion that they were produced in the biosynthesis process through chain elongation of α -linolenic acid. these research results support the idea of changing the fatty acids profile and enriching the chicken meat by adding of foodstuffs rich in PUFA n-3 to chicken diets.

chicken ; feeding ; carcass quality ; fatty acids ; amino acids

nije evidentirano