Impact of different dietary fat sources on performance and immune response of broiler chickens

ABSTRACT

Four groups of broiler chicks [n=40] were fed on concentrate soybean- corn-basal diet to which either beef tallow or linseed oil or mixture blend of linseed oil and beef tallow was included at level of 3 and 4% [starter and finisher, respectively]. The mixture blend of tallow and linseed oil achieved better performance and significantly higher body weight than when each fat source was fed solely. Regarding immune parameters, the linseed oil feeding had significantly improved several immuno-indices [hemagglutinin antibody titers against SRBC and delayed hypersensitivity reaction to phytohemagglutinin-P] in broiler chickens over the control and the other fat sources-fed groups. No significant changes were observed due to the inclusion of different fat sources in the relative weights of spleen and thymus, however, the relative weight of the bursa was significantly increased at age of 3 and 7 weeks in the linseed oil fed group. It is concluded that whereas linseed oil feeding improved several indices of immuno-status in broiler chickens which might be useful to fight infections, it was not able to compete with the tallow-linseed oil mixture in respect to performance. Further studied are needed to evaluate such effects and to underst and the mechanism underlying the modulation of the immune system by linseed oil feeding