1. Practice on castration of piglets in Europe;Fredriksen;Animal,2009
2. Aggressive and sexual behaviour of growing and finishing pigs reared in groups, without castration;Rydhmer;Acta Agric Scand A,2006
3. Immunocastration reduces aggressive and sexual behaviour in male pigs;Rydhmer;Animal,2010
4. EC, 2010. European Declaration on alternatives to surgical castration of pigs [online 16.12.10]. Available from: http://eceuropaeu/food/animal/welfare/farm/docs/castration_pigs_declaration_enpdf [20.05.11].
5. A review of the welfare consequences of surgical castration in piglets and the evaluation of non-surgical methods;Prunier;Anim Welfare,2006