RESUMEN
Selection of sows for large litter size has adverse consequences including lesser and more variable birth weights, reduced piglet viability and greater peri- and post-natal piglet mortality. One approach to improve survival might be to feed caffeine to the sow, which improves piglet viability after induced farrowing, but has not been evaluated in sows which farrow naturally. Large White x Landrace sows were fed 0 (CON: n = 30) or 6 g/day caffeine (CAF: n = 34) with their daily feed from 3 days before expected parturition until farrowing. Numbers of piglets born alive and stillborn, as well as piglet vitality and meconium staining score were recorded at birth. Piglet rectal temperature was measured at 3 and 24 h and piglet survival was recorded through lactation. Compared with CON animals, sows of the CAF group had longer gestations (CON: 115.6 ± 0.3 days; CAF: 116.6 ± 0.3 days, P = 0.01) and piglets of CAF sows had greater rectal temperatures 3 h after birth (CON: 37.6 ± 0.2 °C, CAF 38.0 ± 0.2 °C, P<0.05). Although there was no difference in the stillborn numbers per litter fewer CAF sows delivered stillborn piglets when compared to CON sows (CON: 43.3%, CAF: 20.6%, P = 0.05). Piglet survival to day 18 of lactation was not altered by treatment (CON: 90.4 ± 3.2%, CAF: 92.0 ± 2.4%, P>0.05). The current data suggest that maternal supplementation with caffeine is a promising treatment to prevent premature farrowing and increase piglet temperature at birth, and may decrease the incidence of litters with stillborn piglets.