Boar taint is due to skatole and androstenone, and to a lesser extent by indole. Various strategies are nowadays being investigated to reduce boar taint in entire male pigs, mainly by feeding strategies. Several feed components have been tested, e.g., raw potato starch, lupines, sugar beet pulp and also crude/dried chicory roots or pure inulin from chicory. Chicory has the sesquiterpene lactones (bitter compounds) that reduce skatole. The present study evaluates carcass quality, meat quality and palatability for barrows, immunocastrates and boars and the effect of chicory supplemented feed during 10 days before slaughter on boar meat quality. A total of 97 male piglets (hybrid sow × Pietrain boar) were surgically castrated at 4 after births (barrows, BA), 100 male piglets were kept entire (boars, BO) and 100 male piglets were vaccinated twice against GnRH (boars vaccinated against GnRH, IMP). All BA, IMP and BO began at the same diet. Starting at 10 days before slaughter, BA, IMP and 53 boars received a standard diet and 47 boars received a mixture of 90% standard diet and 5% dried chicory pulp.
The results showed that the lean meat percentage was higher in immunocastrates and boars than in barrows. Muscle thickness was higher for immunocastrates and barrows compared to boars, while fat thickness was lowest for immunocastrates and boars. Barrows, immunocastrates and boars differed in water holding capacity and boar taint. Consumer panels were conducted to evaluate pork palatability. The consumers detected differences in tenderness and juiciness, but not for boar taint. Tenderness and juiciness are mainly affected by the castration method. The chicory feed supplemented in boar feed decreased skatole concentration in backfat, without repercussion on meat quality or palatability. The timing of the second vaccination is important due to its effect on performances and carcass quality, but the influence on meat quality should also be included.
It is concluded that not only boar taint, but also carcass and meat quality should be considered when evaluating alternatives for surgical castration.
M. Aluwé, K.C.M. Langendries, K.M. Bekaert, F.A.M. Tuyttens, D.L. De Brabander, S. De Sme, S. Millet (2013). Effect of surgical castration, immunocastration and chicory-diet on the meat quality and palatability of boars. Meat Science 94; 402–407