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

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.