Normoxic Oxygen at Birth Enhances Piglet Growth and Survival Under Tropical Farm Conditions

Neonatal piglet mortality remains a major challenge in hyper-prolific sow herds, particularly under tropical conditions where low ambient oxygen (18-21%) may exacerbate hypoxia during prolonged farrowing. This study evaluated whether restoring normoxia (21% O₂) immediately after birth improved piglet colostrum intake, blood glucose levels, and survival to 3 d. A total of 1837 piglets from 95 sows were weighed at birth and assigned by litter to exposure to either a normoxic chamber (FiO₂ = 0.21) or ambient-air control (FiO₂ = 0.16-0.18) for 15 min post-partum. Piglet colostrum intake, blood glucose content, and survival to 24-h and 3 d were analyzed using mixed-effects models. Compared with controls, oxygen-supplemented piglets showed higher postnatal oxygen saturation (94.2 ± 3.6 vs. 88.1 ± 3.5%), greater colostrum intake (348 ± 263 vs. 320 ± 233 g), higher blood glucose (97.7 ± 13.0 vs. 93.8 ± 13.1 mg/dL), and increased 3-day survival (86.1% vs. 80.8%; <i>p</i> < 0.01). The effect was most pronounced in piglets < 1.0 kg and >1.3 kg, reflecting improved recovery from transient hypoxia. Mean weaning weight increased by 0.3 kg, indicating sustained benefits in early growth. These findings demonstrate that short-term normoxic oxygen supplementation is a practical, cost-effective intervention that enhances growth, metabolic stability, and survival in neonatal piglets under tropical commercial farm conditions.