Intra-uterine growth retardation affects birthweight and postnatal development in pigs, impairing muscle accretion, duodenal mucosa morphology and carcass traits

Abstract

The present study investigated the occurrence of intra-uterine growth retardation (IUGR) in newborn (n = 40) and 150-day-old (n = 240) pigs of different birthweight ranges (high, HW: 1.8–2.2 kg; low, LW: 0.8–1.2 kg) from higher-parity commercial sows and its impact on their subsequent development and carcass traits in a Brazilian commercial production system. HW newborn pigs had heavier organs than LW pigs (P < 0.01), and all brain : organ weight ratios were higher (P < 0.01) in LW compared with HW offspring, providing strong evidence of IUGR in the LW piglets. HW pigs had higher bodyweights and average daily gain (ADG) in all phases of production (P < 0.05), but ADG in the finisher phase was similar in both groups. Additionally, LW newborn and 150-day-old pigs showed a lower percentage of muscle fibres and a higher percentage of connective tissue in the semitendinosus muscle, greater fibre number per mm2 and a lower height of the duodenal mucosa (P < 0.05). On the other hand, HW pigs had higher hot carcass weight, meat content in the carcass and yield of ham, shoulder and belly (P < 0.01). Hence, lower-birthweight piglets may suffer from IUGR, which impairs their growth performance, muscle accretion, duodenal mucosa morphology and carcass traits.