Document Type : Research Paper
Authors
Abstract
An experiment was conducted in order to assess the effects of different levels of dietary canola meal (CM; 0, 10 and 20 %) and copper (0, 125 and 250 mg/kg) on performance, susceptibility to ascites syndrome and some blood metabolites of broiler chickens. During a six week period of experiment, a total of 495 male broilers (Ross 308) were used in completely randomized design with a 3×3 factorial arrangement with 5 replicates (11 birds per replicate). Feed intake was not significantly affected by treatments during starter, grower and whole periods of the experiment (P>0.05). Body weight gain and feed conversion ratio were significantly impaired (P<0.05) during the starter period when 20% CM was added to the diets. Body weight gain (P<0.01) and feed conversion ratio (P<0.05) were significantly improved by copper supplementation during the growing and the entire periods of the study. Replacing soybean meal by CM significantly increased (P<0.05) the proportions of liver, heart and right ventricular weight:total ventricular weight ratio (RV/TV) at 42 d of age. However, concentrations of haemoglobin, packed cell volume and total erythrocyte count were not affected by the treatments (P>0.05). At 42 d, the concentrations of plasma total protein and enzymes (alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase and lactate dehydrogenase) were similar among the treatments (P>0.05), but concentration of plasma albumin was significantly reduced, when 20% CM was added to the diets. In conclusion, the results of this study did not show any adverse effect for added CM up to 20% on the performance, susceptibility to ascites and plasma enzyme activities. Also, copper supplementation significantly improved growth performance of broiler chickens
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