Abstract: The purpose of this study was to determine the effect of corn-soybean basal diets containing (5% tallow, 5% fish oil and 5% fish oil with vitamin E and zinc) each one in two temperatures (21 and 32°C) on immune response and blood parameters of Arbor Acres (AA) broiler growing from 1-42 days of age. The results demonstrated that heat stress decreased bursa of fabricius weight and spleen weight also high ambient temperature decreased humoral and cell-mediate immune responses and increased hetrophil to lymphocyte ratio (H L-1). Fish oil+vitamin E and zinc diet improved humoral and cell-mediate immune responses, decreased H L-1 ratio and increased bursa of fabricius and spleen weight at two temperatures. The diets containing tallow decreased bursa of fabricius weight and spleen weight. In chicks fed by fish oil, the response to 2-4 Dinitrochlorobenzene (DNCB) was improved. It did not have significant influence on Phytohemagglutinin M (PHA-M) and Sheep Red Blood Cells (SRBC). The results of experimental temperatures on blood parameters demonstrated that high ambient temperature increased cholesterol, triglyceride, glucose, hematocrite percentage and serum Malondialdehyde (MDA), although it did not affect total protein. Higher cholesterol and triglyceride observed in chicks fed with diet containing tallow and higher MDA in chicks fed with diet containing fish oil. Fish oil plus vitamin E and zinc decreased cholesterol, triglyceride, MDA and glucose significantly. Fat type did not affect total serum protein and hematocrite percentage.
A.A. Rashidi, Y. Gofrani Ivari, A. Khatibjoo and R. Vakili, 2010. Effects of Dietary Fat, Vitamin E and Zinc on Immune Response and Blood Parameters of Broiler Reared Under Heat Stress. Research Journal of Poultry Sciences, 3: 32-38. Asian Journal of Information Technology, 18: 250-260.