PSIX-5 Fetal programming in an industry applied setting – Effects of feeding methionine during late gestation on progeny performance, feed efficiency, and carcass quality for feedlot steers

Abstract

Abstract The objective of this study was to assess if rumen-protected methionine supplementation during gestation would impact male offspring performance and carcass quality in an applied setting. Sixty-seven gestating cows were randomly assigned to control (CON), or methionine (MET) treatments. Cows had ad libitum access to hay from a round bale feeder and were fed once daily in a bunk for approximately eight weeks prior to calving either: 0.75 kg/head/d of supplement pellet supplying 12 g rumen-protected MET/cow/d, or identical pellet with no added MET. The 34 steer progeny (MET n = 18; CON n = 16) were transported to a feedlot, assigned to one of seven pens by weight and fed a corn-based grower diet (58% corn silage, 26% alfalfa haylage, 15% soybean meal) for 47 days, followed by a finisher diet (78% high moisture corn, 12% alfalfa haylage, 8% soybean meal) for 115±31.5 days until slaughter. Body weights were recorded biweekly. Organ weights were recorded at slaughter. Carcass quality, meat quality, and rib composition were recorded 24 to 48 hours after slaughter. Data were analyzed using PROC GLIMMIX in SAS, with treatment as the fixed effect, and pen as the random effect. Supplementation of MET during pregnancy increased weaning weight (MET: 311, CON: 291 ±14.8 kg; P ≤ 0.001), final weight (ME: 668, CON: 631 ±16.8 kg; P = 0.01), and individual dry matter intake (MET: 13, CON: 12 ±0.5 kg/d; P = 0.04) during the finishing phase. There was no effect of maternal methionine supplementation (P ≥ 0.05) for average daily gain. Hot carcass weight was greater for MET steers (MET 372 vs. CON 353 ±9.5 kg; P = 0.03), while organ weights and carcass quality were not affected (P ≥ 0.05) by MET supplementation. This study showed that supplementing methionine during late gestation in an industry applied setting improved some offspring performance measures but did not result in enhanced carcass quality.