ProSchwein: Alternatives to the conventional castration of piglets

To prevent the occurrence of meat with boar taint, which is not accepted by the consumer, male piglets are surgically castrated without anaesthesia. As this method of castration will be banned in Switzerland by 1st January 2010, the project ProSchwein investigated different alternatives. A device for inhalation anaesthesia (anaesthetic gas: isoflurane) showed a good anaesthesia for more than 90 % of the castrated animals under field conditions. The studies on rearing entire male pigs revealed a good feed conversion ratio and a high lean meat percentage. The portion of carcasses with boar taint was 5.5 % or higher. Through dietary addition of raw potato starch it was possible to reduce the content of skatole but not the concentration of androstenone. The electronic nose developed by ALP Posieux is capable to detect between 95 and 100 % of the samples exhibiting boar taint according to the classical HPLC method at a laboratory scale. The application of the electronic nose in practice requires for technical adaptations which allows for operation under conditions of a slaughter house. The vaccination against boar taint prevented boar taint efficiently. The vaccine has been registered in Switzerland. Vaccinated animals exhibited similar growth performance and a better feed conversion ratio and a higher carcass quality compared to castrates. Acceptance for the vaccination among consumers is achievable but requires a considerable effort in communication. From an economic point of view anesthesia and the vaccination against boar taint can be recommended for larger farms. For smaller farms the investment for the device for inhalation anesthesia is high.