196 Effects of feed grade L-methionine on intestinal redox status, intestinal development, and growth performance of turkey poults compared with conventional DL-methionine

Abstract

This study was conducted to test the effects of supplemental L-Met (CJ Corp, Seoul, Korea) on redox status, gut development, and growth performance of turkey poults compared with supplemental DL-Met. Three hundred eighty five newly hatched turkey poults were weighed and randomly allotted to 5 treatments in a completely randomized design for 28 d, including a basal diet (BD), the BD +0.145% DL-Met or L-Met, the BD + 0.285% DL-Met or L-Met (representing 60, 75, and 90% of NRC digestible Met + Cys requirement). Feed disappearance and BW were measured weekly. Liver, duodenum, and jejunum samples were collected from 2 random selected birds in each cage on d 7 and 28. Hepatic tissue and duodenal mucosa were used to measure glutathione (GSH), total antioxidant capacity (TAC), protein carbonyl (PC), and malondialdehyde (MDA) as indicators of the redox status. Duodenal and jejunal tissues were used to evaluate morphology. Data were analyzed using the Mixed procedure in SAS. A multilinear regression analysis was used to evaluate the relative bioavailability (RBA) of L-Met to DL-Met. Overall, weight gain (690 to 746 g) and feed intake (1123 to 1248 g) were increased (P < 0.05) as increasing digestible Met + Cys levels from 60 to 90% of the NRC requirement. Birds with L-Met tended (P = 0.053) to have decreased F:G (1.70 to 1.63) compared with birds with DL-Met. Rates of decrease in F:G were different (P < 0.05) between birds with DL-Met and L-Met. Supplementing Met regardless of sources decreased (P < 0.05) MDA (3.29 to 2.47 µmol/g protein) in duodenal mucosa compared with birds in the BD. Supplementing L-Met tended (P < 0.094) to decrease MDA (1.27 to 1.16 µmol/g protein) in hepatic tissues compared with the supplementation of DL-Met. Other oxidative status markers including GSH, TAC, and PC were not affected by Met sources. Supplementation of Met either from DL or L forms did not affect morphology of duodenum and jejunum on d 7 and 28. In conclusion, supplementation of Met enhanced the growth performance and reduced oxidative stress in the gut of turkey poults during the first 28 d of age. Use of L-Met can potentially enhance feed efficiency and reduce systemic oxidative stress compared with the use of DL-Met in turkeys.