Maternal and/or direct feeding of organic acid-preserved cereal grains improves performance and digestive health of pigs from birth to slaughter

Abstract

A 2 × 2 factorial arrangement was conducted to investigate the effects of maternal and/or direct feeding of organic acid (OA)-preserved cereal grains compared to conventionally dried grains on pig growth performance to slaughter, nutrient digestibility, and carcass characteristics. On day 100 of gestation, 80 sows were blocked by parity, body weight (BW), and back-fat thickness and assigned to one of two diets (dried or preserved grain) until weaning. From day 10 postpartum, their progeny were assigned to one of two diets (dried or preserved grain) resulting in four dietary treatments: (1) dried (sow)-dried (progeny), (2) dried-preserved, (3) preserved-dried, and (4) preserved-preserved (n = 20 litters per treatment). Pigs remained in these groups post-weaning (PW) and were monitored until slaughter at 142 days PW (n = 10 pens per treatment). Additionally, faecal samples from pigs in the dried-dried and preserved-preserved groups were collected for microbial analysis throughout production. Progeny from sows fed preserved grain had improved gain-to-feed ratio (G:F) between days 0–14 and 62–142 PW, with enhanced coefficients of apparent total tract digestibility (CATTD) of dry matter (DM), organic matter (OM), and gross energy (GE) on day 30 PW and CATTD of nitrogen (N) at slaughter compared to those from sows fed dried grain (P < 0.05). Pigs directly fed preserved grain exhibited higher daily gain from weaning to slaughter, improved G:F from day 14 PW, and greater BW from day 30 PW compared to those directly fed dried grain (P < 0.05). Pigs fed preserved grain showed increased CATTD of DM, OM, N, and GE on day 30 PW and at slaughter (P < 0.01). Additionally, these pigs had higher carcass weight, kill-out percentage, and muscle depth at slaughter (P < 0.01). Pigs in the preserved-preserved group had higher microbial diversity at weaning and on day 30 PW, with beneficial taxa such as Ruminococcus, Propionibacterium, and Faecalibacterium enriched at key production stages compared to those in the dried-dried group (P < 0.05). In conclusion, maternal feeding of preserved grain improved progeny feed efficiency and CATTD of nutrients, while direct feeding enhanced pig growth performance, CATTD of nutrients, and carcass characteristics. Combined maternal and direct feeding of preserved grain also improved microbial health throughout production.