RESUMO
ObjectiveObserving and analyzing the delivery behaviour of cynomolgus macaques, to establish the criteria for determining the occurrence of delivery in cynomolgus macaques, and then combining with veterinary assistance in order to improve the live birth rate of cynomolgus macaques. MethodsBy backtracking and analyzing the surveillance videos of 112 perinatal cynomolgus macaques with a gestation period of 140 d or more from 2017 to 2021, we observed and recorded the main behavioural manifestations of the cynomolgus macaques during labour, including Valsalva's maneuver, touching and licking the birth canal, lying on their backs or stomachs, and rolling and tumbling of the body. On this basis, we established the weights of delivery-related behavioural indicators and exhaustively analysed the perinatal behavioural performances of 30 cynomolgus macaques for delivery determination. ResultsThe perinatal behavioural validation results of the 30 cynomolgus macaques showed that the behavioural indicators of Valsalva's maneuver, touching and licking the birth canal, lying on the stomach or on the floor, body rolling and tumbling occurred with different frequencies, among which Valsalva's maneuver and lying on the stomach or on the back were the most important, with weight values of 35.5% and 27.2%, respectively. These two behaviours can be used to accurately determine the onset of parturition in cynomolgus macaques. The average live birth rate of the monkeys that were accurately determined to have given birth and were assisted by veterinarians reached 87.1%, which was significantly higher than that of the monkeys that had unassisted spontaneous deliveries, which was 63.5%, and there was a significant difference between these two rates (P<0.05). ConclusionThe combination of accurate birth determination and veterinary assisted delivery can significantly increase the live birth rate of experimental cynomolgus macaques.