29 Maternal mineral source impact on piglet serum mineral and carcass composition at harvest

Abstract Abstract: Introduction Offspring from sows fed Zn, Cu and Mn in the metal methionine hydroxy analogue chelate (MHAC) form vs. sulfate form have been shown to have greater loin eye area at harvest. Data is lacking compared with other mineral sources. Objective Assess the impact of maternal feeding of MHAC or glycinate (Gly) minerals on offspring serum mineral concentration, loin depth and fat depth. Methods From 6 weeks pre-breeding through first gestation, diets were supplemented with 80 mg/kg Zn, 10 mg/kg Cu and 20 mg/kg Mn. From first through third lactation, Zn, Cu and Mn were provided at 50 mg/kg Zn, 10 mg/kg Cu and 20 mg/kg Mn. During parity 3, serum from 1 piglet/litter at 4-d, weaning and 14-d post-weaning was obtained from 20 litters/treatment. At each parity, muscle and backfat depth was determined for approximately 1,000 pigs/treatment. Results There was no treatment (P > 0.15) nor treatment × time interaction (P > 0.22) for serum mineral concentration. Serum Fe, Zn, Cu and Mn were highest at weaning (P < 0.001). Cu and Zn concentrations were 34% and 60% lower respectively at 14-d post-weaning than at 4-d of age. Parity 2 and 3 MHAC offspring had 0.5 mm (P < 0.01) and 1.0 mm (P < 0.001) more muscle depth at 122 kg. Backfat was lower in parity 1 (-0.2 mm; P < 0.01) and parity 3 (-0.4 mm; P < 0.001) MHAC offspring. Conclusions Offspring serum mineral concentration was highest at 4-d of age. Maternal trace mineral source appears to provide an opportunity to impact offspring loin and fat depth at harvest.