Effect of cross-fostering and oral supplementation with colostrums on performance of newborn piglets.

The aim of the experiment was to study the effect on litter performance of two oral supplementation strategies on piglets born weighing 1.35 kg or less (SP; CON: no oral supplementation; COL: supplementation with 15 mL of sow colostrum orally administered to piglets within 4 h after the farrowing was completed). Two levels of cross-fostering strategies, performed 24 h after farrowing, were also studied (HL: litters fixed at 12 piglets, ensuring that less than 50% of the piglets of the litter were SP; LL: litters fixed at 12 piglets, with most of the piglets of the litter being SP; in both cases the aim was to minimize moving piglets from one sow to another as much as possible). The combination of the 2 management strategies described above resulted in a 2 × 2 factorial model. Forty-six litters were used. Litters were allocated to 1 of the 4 treatments: CON-HL, CON-LL, COL-HL, and COL-LL. Piglets were weighed on d 1 and 19 postpartum. Mortality was recorded. On d 4 postpartum, a 2-mL blood sample was obtained from 79 SP piglets born from multiparous sows included in the experiment. To obtain a negative control group, blood samples were obtained on d 4 postpartum from 8 additional SP piglets that were separated from their mothers at birth and bottle fed with milk replacement for 12 h. LL sows had lower within-litter CV of BW at d 1 than HL sows (16.2% vs. 21.9% ± 0.91%; P = 0.003), but they did not differ for litter CV of BW at d 19 (23.2% vs. 23.4% ± 1.72%). At d 19, HL sows had fewer dead piglets per litter than LL sows (0.80 vs. 1.69 ± 0.307; P = 0.022), and COL-HL sows had fewer dead piglets per litter than CON-HL (0.47 vs. 1.14 ± 0.160; P = 0.062). Cross-fostering SP in the same litter did not prevent a litter's CV of BW from increasing at weaning. Piglets from the COL group had higher IgG concentration than piglets from the CON group (P = 0.001). However, piglets from the negative control group had lower IgG concentration than those from the COL and CON groups (5.41 ± 2.320 vs. 30.60 ± 1.582 and 21.53 ± 0.951 mg/mL, respectively; P < 0.001 in both cases). Allocating small piglets to the same litter through cross-fostering had a negative effect on mortality and did not improve litter CV of BW at weaning. Colostrum supplementation of SP piglets improved IgG blood level on d 4. In addition, in nonhomogenized litters, colostrum supplementation of SP piglets might be a good management strategy to improve litter performance.