Efecto de la suplementación de la dieta con aceites de girasol y pescado sobre el rendimiento productivo de los animales y el perfil de ácidos grasos de la leche de ovejas

Abstract

This work was conducted to test the hypothesis that feeding a combination of sunflower oil plus fish oil would enhance the nutritional value of ovine milk without affecting animal performance. Thirty-two Assaf ewes were assigned to 2 treatments (2 lots of 8 animals per treatment): control (20:80 forage:concentrate ratio) or supplemented with 2% sunflower oil plus 1% fish oil (G+P), for 4 weeks. G+P diet remarkably increased the contents of cis-9 trans-11 C18:2 (from 0.73 to 3.00 g/100 g total fatty acids; FA) and trans-11 C18:1 (from 1.58 to 8.05 g/100 g total FA). Most changes in milk FA composition were addressed toward a healthier profile, resulting in a reduction of its atherogenicity index (-47%). However, oil supplementation decreased dry matter intake (-19%) and milk production (-14%), and affected milk composition, with reductions in protein (-8%) and fat contents (-13%). Milk fat reduction is discussed in terms of the joined action of several biohydrogenation intermediates.