Farrowing environment has an impact on sow metabolic status and piglet colostrum intake in early lactation

This study investigated the effects of providing nest-building opportunities prior to parturition on sow serum non-esterified fatty acid (NEFA) concentrations and on colostrum intake of neonatal piglets during the early lactation period. We kept a total of 33 sows in (1) CRATE (N=12): the farrowing crate closed (210×80 cm), with provision of a bucketful of sawdust, (2) PEN (N=11): the farrowing crate opened, with provision of a bucketful of sawdust, (3) NEST (N=10): the farrowing crate opened, with provision of abundant nest-building materials. All sows included in the experiment were confined to the farrowing crates after the first piglet was delivered until seven days post-parturition. We collected sow blood samples for a NEFA assay via indwelling ear vein catheters on days −3, −2, −1, +1, +2, +4, and +7 from parturition. To determine piglet IgG, IgM, and IgA concentrations, we collected blood samples from two healthy female piglets [N (piglet): CRATE=6, PEN=8, NEST=8] from among the gilts in each treatment at 0 h, 12 h, 24 h, 48 h, and 7 d via the jugular vein with a disposable syringe. Piglet growth during early lactation was slower in CRATE than in PEN (P=0.04). Post-natal mortality, including piglet deaths resulting from crushing or other factors, indicated no differences between the three treatments (P>0.10). Compared with sows in limited nest-building environments, sows in NEST tended to have higher serum NEFA concentrations during the experimental periods (P=0.07). Sow serum NEFA concentrations positively correlated with plasma oxytocin concentrations (rs=0.28, P<0.001) and piglet weight gain (r=0.16, P<0.05), and negatively correlated with the post-natal mortality ratio (r=−0.17, P<0.05) for seven days after birth. During early lactation, piglet serum IgG and IgM concentrations in NEST tended to be greater than the other treatments (P=0.05, P=0.07, respectively). IgG, IgM, and IgA concentrations in the piglets were greater in the first 48 h than 7 d after birth (P<0.001, for all). In conclusion, farrowing crates did not reduce piglet post-natal mortality, but provision of nest-building materials to prepartum sows improved sow metabolic status, and successful colostrum intake measured via neonatal piglet serum IgG and IgM concentrations during early lactation. This may have potential to increase piglet survival and growth performance during lactation.