This study was conducted to compare the potential implication of the subcutaneous and perirenal adipose tissues (AT) in the response of lipid metabolism of lactating ewes to sunflower oil, a dietary supplement known to induce changes in milk fatty acid (FA) composition. Ten sheep (5 animals/treatment) received a total mixed ration based on alfalfa hay and a concentrate (F:C 60:40), supplemented with 0 (Control) or 25 (Gi) g of sunflower oil/kg dry matter, for 7 weeks. At the end of the experiment, the ewes were euthanized and samples of subcutaneous and perirenal AT were collected to examine their FA profile and the mRNA abundance of candidate genes involved in lipogenesis. With regard to FA composition, neither the little effects of Gi nor the great differences between fat depots appeared to be linked to differences in mRNA abundance. The results suggest a low response of the studied genes in the subcutaneous and perirenal AT in the ad libitum fed sheep, in mid-lactation, used in this trial. They also suggest a minimal contribution of gene expression to the nutritional regulation of lipogenesis in these depots, at least with the examined diets.

Este trabajo ha sido financiado por el MINECO (Proy. AGL2011-23700) y la UMR1213 (INRA, Francia). T. Castro-Carrera disfruta de una beca JAE-CSIC cofinanciada por el Fondo Social Europeo.

3 páginas, 2 tablas.-- Trabajo presentado a las XV Jornadas sobre Producción Animal AIDA (Zaragoza, 14 al 15 de mayo, 2013).

Peer reviewed