Supplemental carbohydrase enzyme and methionine in broilers fed flaxseed: effects on growth performance, nutrient retention, muscle lipids, and jejunal morphology

Abstract

The present study investigated the effect of carbohydrase enzyme, methionine ( Met ) (100% above Cobb 500 requirement level), or their combination on growth performance, carcass yield, total tract retention ( TTR ) of DM, CP, fatty acid ( FA ), muscle FA composition, lipid peroxidation products, and jejunum histomorphology in broiler chickens fed 10% flaxseed-containing diets. One hundred and twenty (n = 120) day-old Cobb chicks were fed corn-soybean meal–based diet containing 0% flaxseed (control), 10% whole flaxseed (diet 1), diet 1 + 0.05% carbohydrase enzyme (diet 2), diet 1 + 100% more Cobb 500 Met requirement (diet 3), and diet 1 + 0.05% carbohydrase enzyme + 100% more Cobb 500 Met requirement (diet 4) for 42 d. The data were analyzed by ANOVA with 5 treatments with 4 replications in a completely randomized design. At day 42, BW gain was the highest in control when compared to flaxseed-containing diets ( P < 0.05). Dry matter TTR was higher in diet 3 and diet 4 than that in diet 1 and diet 2 ( P < 0.05), and CP TTR was highest in diet 3 compared with that in diet 1 and diet 2 ( P < 0.05). Supplementing Met increased linoleic and α-linolenic acid TTR in birds fed flaxseed ( P < 0.05). Total and long-chain (≥20C) n-3 FA was higher in the thigh muscle of broilers fed diet 3 and diet 4 than in those fed diet 1, diet 2, and control ( P < 0.05). Lipid oxidation products in the thigh muscle was the highest in birds fed diet 4 ( P < 0.05). Jejunal villous height, villous perimeter, and villous surface area were highest in birds fed diet 1 ( P < 0.05). In conclusion, supplementing Met, or its combination with carbohydrase enzyme, increased DM, CP, and essential FA TTR and thigh muscle n-3 FA in broilers fed flaxseed. However, supplementing Met or its combination reduced BW gain and negatively affected jejunal morphology in broilers fed flaxseed.