Effects of L-Arginine levels supplementation on some blood parameters, thyroid hormones, mortality and performance of broilers with cold-induced ascites

An experiment was conducted to investigate the effects of arginine levels in drinking water on Mortality, performance and some blood parameters in broiler chickens with ascites. Two hundred forty 1-d-old Ross male broilers were randomly allocated into 3 treatments (with 4 replicate each containing 20 chicks). From d 14 to 42, all the chicks were exposed to low ambient temperature (10 to 15 °C) to induce ascits. From d 14, the drinking water were supplemented with arginine at levels of %0 (Control), % 0.15 and % 0.3. Body weight gain, feed intake and feed conversion ratio were measured from week 3. Blood parameters (urea, uric acid, triglyceride, cholesterol, High Density Lipoprotein (HDL) and thyroid hormones triiodothyronine (T₃) & thyroxin (T₄) were determined at days 21 and 42 of age. Two chicks from each replicate were randomly selected and slaughtered and then ascetic Index (ratio of right ventricle weight to total ventricle weight) calculated at 42 days of age. Mortality was recorded daily, and all of the dead birds were examined for ascites throughout the study. Results showed: % 0.3 arginine treatments had the highest body weight gain and the lowest feed conversion ratio in total period (p<0.05). Moreover, % 0.3 arginine significantly increase plasma concentration of thyroid hormones triiodothyronine (T₃) & thyroxin (T₄) and decreased urea, triglyceride, cholesterol and HDL at day 42 (p<0.05). Plasma level of uric acid was significantly increased by % 0.3 arginine at day 21. Furthermore, Ascetic Index and mortality due to ascites, were significantly lower in % 0.3 arginine group (p<0.05). In conclusion, supplementation of % 0.3 arginine in drinking water in broilers under ascites, significantly improved performance and reduced mortality