determination the effects of natural antioxidants and fat sources on blood lipids, metabolites, and antioxidant status of heat stressed broilers.

this experiment was conducted to evaluate the effects of turmeric powder (trp), tomato pomace (tp), fat sources (canola oil, soybean oil and tallow) on immune system and jejunum morphometric parameters of heat stressed broiler chickens. five hundred four one-d-old ross broiler were randomly distributed to 36 experimental units and 12 dietary treatments (3 replicates with 12 birds in each). the completely randomized design with factorial arrangement 3× 2× 2 (3 oils: canola, soybean, tallow, 2 trp levels involved 0.4, 0.8% and 2 tp levels 3, 5%) were used. a daily heat stressed schedule (33oc for 5 h) was applied from 29 to 42d. at 28 and 42 d of age, two birds were bled and plasma and hemolysate were collected. the blood cholesterol at phs and ldl-c were decreased and hdl-c were increased when birds fed canola and soybean oil. trp diet decreased the ldl-c and increased hdl-c. blood lipids were not affected by tp diets. canola oil decreased heterophil:lymphocyte  (h:l)ratio at phs, however; trp and tp decreased h:l ratio at ahs. the lower blood enzyme activity of alp, ast and alt were decreased in heat stressed birds fed canola oil as compared to tallow. tp also affect alp and alt activity. the higher activity of gpx and lower tbars index were observed in birds fed canola oil or trp diet. therefore, addition of canola oil with trp or tp could decrease the blood lipids, liver enzyme activity, the h:l ratio and improve the antioxidant status of broiler under heat stress.