Effect of dietary fat source on antibody production and lymphocyte proliferation in chickens

The purpose of the present study was to assess the effect of fat source on the immune response of chickens. One-day-old pullets were fed corn and soybean meal-based diets containing 7% by weight one of the following fat sources: lard, corn oil, canola oil, linseed oil (LO), or fish oil (FO). After being fed experimental diets for 3 wk, humoral and cellular immune responses were assessed. Chicks were injected with SRBC and antibody titers were measured, 7 days later, by hemagglutination. Concanavalin A (Con A), pokeweed mitogen (PWM), or lipopolysaccharide (LPS)-stimulated proliferation of splenocytes was assessed by [3H]thymidine incorporation. Results demonstrated that antibody titers in FO-fed chicks were higher (P less than .005) compared with titers in chicks fed the other fat sources. The proliferative response to Con A and PWM were 30 to 50% lower (P less than .13 and P less than .05, respectively) in chicks fed the oils rich in omega-3 fatty acids, LO and FO. The response to LPS was poor. The effect of dietary fats source on lymphocyte proliferation was completely abrogated when autologous chicken serum was excluded from the culture medium. Fat source also seemed to affect growth and feed intake of the chickens. In conclusion, dietary fat source has a significant impact on the immune response of chickens.