A two-diet feeding regime for lactating sows reduced nutrient deficiency in early lactation and improved milk yield

The objective of the present study was to evaluate whether a new feeding concept composed of two dietary components fed daily throughout lactation could minimize sow weight loss and increase milk yield (MY) and piglet weight gain. In total, 14 sows were included in the experiment from parturition until weaning 28 d later. The sows were fed one of two dietary feeding regimes from lactation d 2 and throughout lactation. The 1-diet feeding regime represented the Danish feeding standards and recommendations. The new 2-diet regime supplied sows feed and nutrients (ME and AA) according to their individual requirements for maintenance and milk production. Thus, a basal diet was formulated and supplied to meet the energy requirement for maintenance and a lactation supplement was formulated to meet the dynamic requirement of nutrients for milk production. Sows and piglets were weighed and feed intake was recorded weekly. In addition, weekly milk samples and blood samples on d 3 and 17 were collected. Furthermore, sows were enriched with D2O (deuterated water) on d 2 and 28 after parturition to calculate body pools of fat and protein. Sows' feed intake and weight loss interacted with diet regime across wk of lactation. In lactation wk 4, sows fed the 1-diet feeding regime produced less milk (13.0 kg/d) than the sows fed the 2-diet regime (14.9 kg/d). Piglet weight gain was numerically higher (P=0.11) throughout the lactation period for sows fed the 2-diet regime. Dietary regime had no effect on milk composition of DM (dry matter), fat and protein (P=0.99, 0.82 and 0.94). Milk lactose content was, however, higher for sows fed the 1-diet feeding regime (P=0.01). Sows on both dietary regimes were in negative energy balance throughout lactation. Sows fed the 1-diet regime were negative in N and Lys and reached a positive or zero balance in late lactation. For the 2-diet feeding regime sows' N and Lys balance was positive throughout lactation, and N loss was higher for sows fed the 2-diet feeding regime. The concentration of urea in plasma was lower for sows fed the 1-diet feeding regime. In conclusion, feeding lactating sows with the 2-diet feeding regime throughout lactation improved sows' MY and mean piglet weight as lactation progressed, and sow weight loss was reduced in early lactation. By feeding sows with the 2-diet feeding regime it was also possible to reduce nutrient deficiency throughout lactation.