Dietary energy sources during late gestation and lactation of sows: effects on performance, glucolipid metabolism, oxidative status of sows, and their offspring

In this study, the effects of maternal energy sources during late gestation and lactation on the performance, glucolipid metabolism, and oxidative status of sows and their offspring were investigated using a total of 75 (2 to 6 of parity) Landrace x Large White sows at day 85 of gestation under 3 different dietary treatments: SO diet (basal diet plus 3.0% and 5.0% soybean oil during late gestation and lactation, respectively), FO diet (basal diet plus 3.0%/5.0% fish oil during late gestation and lactation, respectively), and CS diet (basal diet plus 32%/42% corn starch during late gestation and lactation, respectively). All the 3 groups showed no obvious differences (P > 0.05) in the number of total piglets born, born alive, after cross-fostering, and at weaning, whereas the CS group exhibited a shorter farrowing duration (P < 0.05) and lower stillbirth rate (P < 0.05) when compared with the SO group. In addition, litter weight at birth was significantly higher in the CS group than in the SO or FO group (P < 0.05). Despite no notable differences in the ADG of suckling piglets among dietary treatments (P > 0.05), the CS group had greater feed intake than the SO group during the lactation period (P < 0.05). In neonatal piglets with normal birth weight (NBW, 1.3 to 1.5 kg), the CS group was lower than the SO group in the content of liver glycogen (P < 0.05) and the mRNA abundances of fatty acid synthase, acetyl-CoA carboxylase, fatty acid-binding protein 1, and acyl-CoA oxidase (P < 0.05). Interestingly, compared with the SO group, the FO group had a lower preweaning mortality rate (P < 0.05), but greater liver glycogen pools (P < 0.05) in neonatal piglets with low birth weight (LBW, <1.1 kg). Compared with the CS group, the FO group showed an increase in the plasma malondialdehyde levels (P < 0.05) of sows, as well as an increase of 8-hydroxy-deoxyguanosine (P < 0.05) and a decrease of ferric reducing ability of plasma (P < 0.05) in NBW piglets. Overall, the diet rich in starch decreased the stillbirth rate and increased the litter weight of neonatal piglets, the dietary supplementation with fish oil decreased preweaning mortality rate, and the diet with a low n6:n3 ratio increased the oxidative status of sows and their offspring.