Efecto del sexo y la restricción de crecimiento intrauterino en la composición de ácidos grasos en lechones ibéricos recién nacidos

Abstract

The occurrence of Intrauterine Growth Restriction is a spontaneous event which negatively influences the postnatal development. This effect has been assessed in pigs, but there are few data about potential changes in fatty acid composition. Hence, we analyzed fatty acids composition in the liver and muscle (longissimus dorsi) of 43 Iberian x Duroc newborn piglets. Sixteen of them were classified as Normal Birth-Weight piglets (8 males and 8 females, average weight 1402.2 ±321 g) and 27 were identified as Low Birth-Weight piglets (14 males and 13 females, average weight 635.7 ±159.1 g; P<0.0001). Regarding the fatty acid composition in both liver and muscle, significant differences were observed between Low Birth-Weight and Normal Birth-Weight. Therefore, the liver fatty acids also showed sex-related significant effects; especially in the polar fraction. The analysis of the neutral fraction in muscle showed lower monounsaturated fatty acids (MUFA; P<0.0001) concentration and higher polyunsaturated fatty acids (PUFA; P<0.005) concentration in Low Birth-Weight neonates. In relation to polar lipids of the liver, Low Birth-Weight piglets had lower saturated fatty acids concentration (SFA) than Normal Birth-Weight (P<0.05). Sex affected the neutral MUFA/SFA ratio and the polar polyunsaturated fatty acids concentration of the liver, being respectively higher and lower in females (P<0.05 for both). In conclusion, the present study shows that Intrauterine Growth Restriction and sex are related to changes in the muscle and liver fatty acid composition that may affect meat quality.