Reducing sow confinement during farrowing and in early lactation increases piglet mortality1

The aim of this study was to investigate the effect of sow confinement and nonconfinement during parturition and early lactation on the performance of sows and piglets prior to weaning. Sows and their litters were housed in either a conventional farrowing crate (control; 1.7 × 2.4 m) or a swing-sided pen (2.8 × 2.15 m). Sows housed in the swing-sided pen had the crate open (open) or closed (closed) during farrowing and opened on d 3 (LAC3) or 7 (LAC7) of lactation. Data are means ± SEM. The numbers of total and liveborn piglets were not different between treatments and averaged 13.1 ± 0.4 and 12.3 ± 0.2 piglets/litter, respectively. Sows housed in a farrowing crate had a greater (P = 0.03) number of stillborn piglets compared with open sows from pens (1.1 ± 0.2 vs. 0.6 ± 0.1 piglets/ litter, respectively). Live-born piglet mortality before litter equalization on d 1 was greater (P 0.05). Total live-born piglet mortality from birth until weaning for the control, closedLAC7, closedLAC3, openLAC7, and openLAC3 was 1.86 ± 0.19, 1.95 ± 0.23, 2.10 ± 0.39, 2.45 ± 0.27, and 3.74 ± 0.48, piglets/litter, respectively. Total live-born piglet mortality from birth until weaning was greater in the openLAC3 and openLAC7 treatments compared to control (P < 0.01), and openLAC3 was also greater than openLAC7, closedLAC3, and closedLAC7 (P < 0.01). The current data indicated that reducing sow confinement during parturition decreased stillborn number but increased live-born piglet mortality compared to a farrowing crate, and removing confinement on d 3 of lactation further increased total piglet mortality compared to removing sow confinement on d 7 of lactation in sows that farrowed open. Sows that were confined during farrowing and until d 3 or 7 of lactation in a swing-sided pen had a similar piglet mortality compared to those in a farrowing crate

Methyl donor supplementation of gestating sow diets improves pregnancy outcomes and litter size

Maternal intake of B-vitamin and methyl donors can affect sow prolificacy. A total of 1079 Large White/Landrace sows (parities 2–9 at mating) were used in a 2 by 2 by 2 factorial design to determine the effects of two levels of betaine supplementation (0 versus 3 g added betaine/kg feed), two levels of folic acid plus vitamin B₁₂ supplementation (0 versus 20 mg/kg folic acid plus 150 µg/kg vitamin B₁₂) during gestation, and two parity groups (parity 2 and 3 versus parity 4 and greater) on litter size and pregnancy outcomes. The number of sows returning to oestrus post-insemination, as well as the number of early (Day 30) pregnancy losses were recorded. At farrowing, the total number of piglets born, the number of piglets born alive and dead, as well as the number of mummified fetuses were recorded. Pre-prandial blood samples were collected from a subset of 20 sows/treatment on Days 3, 30 and 107 of gestation to analyse homocysteine. The incidence of early pregnancy loss was reduced (P < 0.001) by folic acid plus vitamin B₁₂ supplementation (0.03 versus 0.07). There was a significant interaction between parity at mating (parities 2 and 3 versus parity 4 and greater) and the addition of betaine or folic acid plus vitamin B₁₂ to the gestation diet on litter size. Litter size was higher (0.5 piglets; P < 0.05) for betaine supplemented, compared with unsupplemented, parity 4 plus sows. Folic acid plus vitamin B₁₂-supplemented parity 2 and 3 sows gave birth to more (P < 0.05) piglets than all other treatment groups. Folic acid plus vitamin B₁₂ supplementation decreased (P < 0.001) plasma homocysteine concentration by 2.2 and 2.8 μM, respectively, on Days 3 and 107 of gestation. However, betaine supplementation decreased (P < 0.05) homocysteine on Day 3 only. Overall, folic acid plus vitamin B₁₂ supplementation decreased incidences of early pregnancy failure and increased litter size in early parity sows, while betaine increased litter size in older parity sows.W. H. E. J. van Wettere, R. J. Smits and P. E. Hughe