[Piglet castration--pain sensation and pain elimination]

Electroencephalographic (EEG) recordings performed in piglets during Trapanal anaesthesia showed distinct changes in bioelectrical brain activity in some piglets when castration was carried out. Only an additional extradural anaesthesia seemed to interrupt the transmission of peripheral pain stimuli to the central nervous system. Based on the protocol used EEG did not reveal a marked response to noxious stimulation. Castration of piglets up to two weeks of age were performed during general anaesthesia with Trapanal or Disoprivan or local anaesthesia with Hostacain or without any anaesthesia. The different modes of anaesthesia have had no effects to postoperative wound healing and weight gain between groups as well as between males and females within single groups. With regard to insufficient analgesia and/or partially extreme secondary effects the application of investigated anaesthetic methods on the occasion of castration of piglets is not justifiable at present. Castration in piglets up to an age of two month without anaesthesia is allowed by the animal protection law. However, due to improved wound healing and decreased response to surgical stimulus we suggest to perform castration during the first 10 days after delivery.