Abstract:
Castration is a controversial practice in swine production because in some countries is still performed without
anaesthesia, and therefore causes intense suffering and stress to animals. This study investigated the effect of
pre-surgical administration of local anaesthesia (LA) on the growth performance of piglets until the end of the
growth phase (102 days). Piglets aged 3 to 5 days were selected in pairs of similar weights and same age. They
were originated from 22 litters. The groups were randomly assigned to one of two treatments. Castration was
performed with (LA; n = 45) or without (NLA; n = 45) intra-testicular administration of 0.5 mL of 2% lidocaine
plus adrenaline per testicle, administered by an automatic repeating vaccinator. Castration was performed
10 min later. Average daily weight gain and economic impact were evaluated between the intervals before
castration until 21 (weaning phase), before castration until 60 (end of the initial nursery phase) and before
castration until 102 (growth phase) days of age. Average daily weight gain data were analyzed by comparing the
average daily weight gain between the weaning phase, 60 and 102 days of age versus the initial weight (precastration).
At the end of the growing phase, animals treated with LA showed greater weight gain than animals
castrated without anaesthesia. LA also showed improved cost:benefit ratio and theore might provide greater
economic benefit under the conditions used in this study. Our findings have proved that castration with LA
improves long-term weight gain of piglets.
