Articles | Volume 59, issue 3
Original study
12 Jul 2016
Original study |  | 12 Jul 2016

Difference in fatty acid composition and related nutritional indices of meat between two lines of slow-growing chickens slaughtered at different ages

Teodora Popova, Maya Ignatova, Evgeni Petkov, and Nikola Stanišić

Abstract. The fatty acid profile and the related indices of the nutritional quality of breast and thigh muscles were studied in two lines of chickens – La Belle (LB) and White Plymouth Rock (WPR) – slaughtered at the age of 9 and 18 weeks. The fatty acid profile was more affected by the age than the line of the birds; however, the influence of both differed between the breast and thigh. The content of total saturated fatty acids (SFAs) increased in the thigh (P <  0.01), while that of the monounsaturated fatty acids (MUFAs) decreased with age in both muscles (P <  0.001). This corresponded to the significant decrease in C18:1 in the older chickens and the lower desaturase activity (P <  0.001). The contents of C20:4n-6, C22:5n-3 and C22:6n-3 and the total amount of polyunsaturated fatty acids (PUFAs) in breast were higher (P < 0.001) at the age of 18 weeks. A similar pattern in the individual and total PUFA was observed in the thighs. The effect of line was more visible in the breast, leading to a lower C14:0 content and C20:5n-3 and a higher C18:0 content in the WPR chickens (P <  0.001), corresponding to the higher elongase and thioesterase indices in these birds. Both atherogenic (AI) and thrombogenic (TI) indices were lowered, while the ratio of hypocholesterolemic ∕ hypercholesterolemic fatty acids (h ∕ H) and polyunsaturated ∕ saturated fatty acids (P ∕ S) increased in the breast of the birds at 18 weeks. In breast and thigh meat, the ratio of n-6 ∕ n-3 PUFA decreased in the older chickens (P <  0.001).

Short summary
Fatty acids and nutritional indices in meat were studied in La Belle and White Plymouth Rock birds at 9 and 18 weeks of age. The study is the first in Bulgaria to assess the potential of lines of the national gene pool to produce slow-growing chickens with a high quality of meat in regard to its lipid profile, affected by line and age of the birds. Total monounsaturated fatty acids decreased, but polyunsaturated acids increased with age, leading to beneficial changes in the nutritional indices.