La survie sous la mère : corrélation avec la température tympanique pour les porcelets légers de poids « normal »

Dans l’heure qui suit la naissance, le porcelet voit sa température chuter. Ceci étant pénalisant pour la survie, des outils de contrôle rapides, peu coûteux et peu invasifs peuvent être utiles. Cette étude évalue l’intérêt de la température tympanique pour détecter les porcelets en hypothermie et préciser les liens avec la survie selon les seuils, les poids de naissance et les tailles de portées.

Pre-weaning survival is related to the tympanic temperature of piglets of low and normal birthweights

In large litters, poor colostrum intake and hypothermia are major causes of high pre-weaning mortality, especially for piglets with low birthweight. As new-borns experience a severe drop in body temperature, detection of hypothermia is essential. The aim of this study was to evaluate the suitability of monitoring tympanic temperature, known to be the most accurate alternative to rectal monitoring. The study was performed at the IFIP experimental farm with 63 litters from three batches of 24 sows (18.7 ± 4.7 total born). Temperatures were recorded for 1013 piglets within 24 h of birth and at the beginning (T1) and end (T2) of standard care procedures, using an infrared ear thermometer, and pre-weaning mortality was monitored. T1 varied from 34.2-40.7°C (mean 38.6 ± 0.8 °C), with 14 %, 34 % and 69 % of piglets with temperatures below 38.0, 38.5 and 39.0°C respectively. Severe hypothermia (< 38°C) increased in large litters and was more frequent (53 % vs 8 %, P < 0.001) for piglets < 1 kg at birth. Mortality by day five (13.2 %) was related to hypothermia (P < 0.001), with the best prediction accuracy at the 38.0°C threshold. Hypothermia influenced mortality (P < 0.001), with more severity for birthweights below 1 kg (87 % vs 34 %) than above 1 kg (25 % vs 4 %). T2 improved during care (39.0 ± 0.8°C), with only 9 % piglets below the 38.0°C threshold. Mortality peaked (84 %) for piglets that remained cold, and high (> 30 %) when hypothermia was experienced at least once. The results confirm that infrared tympanic temperature monitoring may be suitable for early on-farm detection of hypothermia and mortality risks.