Feeding Dry Olive Cake Modifies Subcutaneous Fat Composition in Lambs, Noting Cake Resistance to Degradation and Peroxidation

Raúl Vera1*, Claudio Aguilar1, Rodrigo Lira1, Paula Toro1, Luis Barrales1, Iván Peña1, Fernando Squella2, Patricio Pérez3, Javiera Quenaya1, Hanja Yutronic1, and Ignacio Briones4
The purpose of this experiment was to determine the extent to which lamb carcass quality and fat composition could be altered by applying a dry olive cake-based ration instead of a conventional ration or pasture feeding. Three treatments were compared in a completely randomized experiment using 36 single male Suffolk Down lambs with an initial age and live weight of 80 d and 25 kg, respectively. The three treatments were: (a) suckling lambs kept with their mothers on annual Mediterranean grassland (GRAZE); (b) weaned stall-fed lambs on a control ration (CONC); and (c) weaned stall-fed lambs on an olive cake-based ration (CAKE). At the end of the 28-d experimental period, lambs were slaughtered, carcass quality evaluated, and samples of subcutaneous fat analyzed for fatty acids. Treatments did not differ in weight gain or carcass weight and quality, but highly significant differences were found in several fatty acid contents. CAKE animals had reduced palmitic acid as well as increased oleic and stearic acid contents. Atherogenic and thrombogenic indices improved with cake feeding. Principal component and discriminant analyses clearly differentiated treatments suggesting they could be applicable for traceability purposes. A laboratory experiment demonstrated that with or without added vitamin E, the dry olive cake did not alter its lipid properties with increased storage time.
Keywords: sheep dry olive cake fatty acids, body composition
1Pontificia Universidad Católica, Facultad de Agronomía e Ingeniería Forestal, Casilla 6177, Santiago, Chile. *Corresponding author (rverai@uc.cl).
2Instituto de Investigaciones Agropecuarias INIA, Centro Experimental Hidango, Casilla 3, Litueche, Chile.
3Universidad de Chile, Facultad de Ciencias Veterinarias y Pecuarias, Av. Santa Rosa 11735, La Pintana, Santiago, Chile.
4Fondo para la Innovación Agraria, Ministerio de Agricultura, Loreley 1582, La Reina, Santiago, Chile.