Effect of oxygen inhalation at birth on the reduction of early postnatal mortality in pigs.

Asphyxia during delivery is considered a main cause of stillbirth in pigs, but piglets suffering from intermittent asphyxia during delivery are also less viable at birth and less prone to adapt to extrauterine life. In an effort to improve pig viability, one attractive solution would be to increase oxygen supply through oxygen inhalation by the newborn pig. The objective of this study was to test effects of oxygen inhalation immediately after birth on various physiological parameters and piglet survival. The experiment was performed on 252 Piétrain x Large White piglets, half of them reoxygenated immediately after birth. They were maintained during 20 min in a chamber where oxygen concentration was monitored at 40% and were then put back with the sow and the control pigs. Oxygen inhalation affected piglet metabolism. Through stimulation of oxidative metabolism (reduction of circulating levels of lactate) and lowering of the level of postnatal hypothermia (particularly for the lightest pigs), oxygen inhalation increased piglet viability and reduced mortality during the 1st d of life by 75% (2 vs 8%). No additional effects were observed during the following days and overall mortality between birth and weaning at 21 d was reduced from 12 to 8%.