Newborn traits associated with pre-weaning growth and survival in piglets

Objective: Piglet pre-weaning mortality is an important variable indicating the efficacy of farrowing management and animal well-being during lactation. The present study determined the association of newborn traits measured soon after birth with piglet pre-weaning mortality and growth. Methods: In total, 805 piglets born from 57 multiparous sows were investigated. Their blood oxygen saturation, blood glucose and rectal temperature at 24 h after birth (RT24h) were monitored. Birth order, sex, skin color, integrity of the umbilical cord, attempts to stand and birth intervention were monitored. Piglets were weighed at day 0, 7, and 21 to evaluate average daily gain (ADG). Results: Piglet pre-weaning mortality for lactation period was 12.6% and cumulative mortality during the first 7 days of age was 8.6%. A higher proportion of piglets with pale skin color died compared to piglets with normal skin color (26.7% vs 7.7%, p<0.001). A higher (p<0.001) proportion of piglets that attempted to stand after 5 min (38.5%) died compared to piglets that attempted to stand within 1 min (6.3%) after birth. Piglet body weight at birth ($BW_B$), blood glucose and the number of piglets born alive (BA) were correlated with ADG (p<0.05). Piglets with $BW_B$ <1.30 kg had higher (p<0.001) mortality rate than piglets with $BW_B{\geq}1.80 kg$ (19.0% vs 3.3%) and piglets with $BW_B$ 1.30 to 1.79 kg (4.0%). Piglet with RT24h <$37.0^{\circ}C$ had higher (p<0.001) mortality rate (86.2%) than piglets with RT24h >$38.5^{\circ}C$ (3.9%). Conclusion: Low $BW_B$ and low RT24h compromise piglet survival during the lactation period in the tropical conditions. Piglets in the litters with a high BA, low $BW_B$ and low blood glucose have reduced ADG.