摘要Background:The aim of this study was to determine how maternal undernutrition during pregnancy and offspring birth-weight can affect the postnatal development of offspring under farm conditions,which may lead to consequences in its meat and carcass quality.The current study involved a total of 80 litters from Iberian sows fed a diet fulfilling daily requirements (n =47;control) or providing 70％ daily requirements (n =33;underfed) from d 38 to d 90 of gestation when fetal tissue development begins.After birth,piglets born live were classified as low birthweight (LBW;＜ 1 kg) and normal birth-weight (NBW;＞1 kg).During the growing phase,240 control and 230 underfed pigs (50％ males and females) distributed by BW category and sex were studied until the slaughter.Results:At birth and weaning,there were significant differences in all morphological measures and weight between NBW and LBW piglets as expected (P ＜ 0.0005),but few effects of the gestational feed restriction.During the growing phase,NBW pigs continued with higher weight than LBW pigs on all the days of evaluation (P ＜ 0.05),even though control-LBW-females and LBW-males showed a catch-up growth.However,underfed pigs showed slower growth and higher feed conversion ratio than control pigs (P ＜ 0.0001) at 215 days old.Moreover,the average daily weight gain (ADWG) for the overall period was greater for NBW,male and control pigs than for their LBW,female and underfed pigs (P ＜ 0.0001,P＜ 0.0005 and P＜ 0.05,respectively) and NBW pigs were slaughtered at a younger age than LBW pigs (P＜ 0.0001).After slaughtering,control pigs also had higher carcass yield and backfat depth than underfed pigs (P ＜ 0.0005) and the maternal nutritional effect caused main changes in the polar lipid fraction of liver and loin.The fatty acid composition of loin in control pigs had higher C18:1 n-9 and n-3 FA concentrations,as well as lower ∑n-6/∑n-3 ratio,than in underfed pigs (P ＜ 0.005).Conclusions:In brief,results showed that the effects of maternal nutritional restriction appeared and increased with offspring age,causing worse developmental patterns for underfed pigs than for control pigs.