Comparative fatty acid composition of three adipose tissues in sheep breeds with different tail morphologies rearing...

Adipose tissues differ widely in fatty acid composition depending on breed, and these differences have important implications for meat quality, flavor development, and human health. This study aimed to compare the fatty acid profiles of omental, tail, and inguinal fat in Merino, Akkaraman, and Kıvırcık lambs (n = 6 per group) reared under identical conditions and to determine whether tail morphology is associated with variation in adipose tissue lipid composition. All lambs were male and 5 months of age. The final body weights were 37.9 ± 1.3, 39.5 ± 1.2, and 36.0 ± 1.4 kg for Merino, Akkaraman, and Kıvırcık lambs, respectively (P > 0.05). All lambs were reared under uniform management conditions at a commercial farm in the Central Anatolia Region, Türkiye. After slaughter, fatty acids were examined in omental, tail, and inguinal fat samples. Significant breed-related differences were identified only for lauric acid, stearic acid, total saturated fatty acids (ΣSFA), total unsaturated fatty acids (ΣUFA), the total unsaturated fatty acid to total saturated fatty acid ratio (ΣUFA/ΣSFA), and the thrombogenic index (TI) (P ≤ 0.05). Merino exhibited the highest lauric acid concentration, whereas Kıvırcık sheep had the highest stearic acid concentration (P < 0.05). Compared with Kıvırcık, Merino also showed lower ΣSFA and TI but higher ΣUFA and ΣUFA/ΣSFA values (P ≤ 0.001). Across adipose tissues, tail fat consistently contained the highest levels of myristoleic, palmitoleic, heptadecenoic, oleic, γ-linolenic, α-linolenic, and behenic acids, while inguinal fat contained the lowest levels of these fatty acids (P < 0.05). Flavor-related fatty acids varied among adipose tissues, with arachidonic acid most abundant in inguinal fat and tricosylic acid peaking in omental tissue. Omega-3 (n3) fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were highest in omental fat but lowest in tail fat. Total n-3 fatty acids followed the same pattern, whereas the omega-6 to omega-3 fatty acid ratio (n6/n3), atherogenic index (AI), and thrombogenic index (TI) were highest in tail fat and lowest in omental fat (P < 0.05). Stearic acid, total saturated fatty acids (ΣSFA), total monounsaturated fatty acids (ΣMUFA), total unsaturated fatty acids (ΣUFA), and thrombogenic index (TI) demonstrated significant interactions between breed and adipose tissue (P < 0.05). Overall, the results indicate that both breed with different tail morphologies and adipose tissue substantially influence fatty acid composition. However, each breed displays a distinct lipid profile independent of tail morphology.