This study aimed to explore dietary replacement soybean meal (SBM) with local pea seeds (PS-L) and the effects of surgically castrated (CM) or immunocastration (IM) in heavy male pigs, on growth performance, feeding behaviour, and tail and ear lesions. Four treatments were arranged factorially (2 × 2), with two sexes and two dietary treatments (96 pigs in eight pens). The inclusion of PS-L was 25%, 30%, and 40% during three phases (40−80 kg, 80−110 kg, and 110−140 kg, respectively). No difference in average daily feed intake (ADFI) and body-weight (BW) between PS-L and SBM could be demonstrated (p > 0.05), but PS-L diet decreased the average daily gain (ADG) at 110−140 kg of BW (p < 0.001) and increased feed conversion rate (FCR) (p < 0.05). The ADG was higher (p < 0.01) in IM than CM in all fattening periods, and the FCR in IM was lower (p < 0.05) than in barrows. IM pigs had lower dressing percentage than CM (p < 0.01). Pigs fed a PS-L diet ate faster but increased their passive behaviour compared with those fed SBM. In conclusion, the PS-L diet did not reduce BW and improved passive behaviour, and IM grew more efficiently, regardless of diet.
Keywords: feeding behaviour; field pea; heavy pig; immunocastrated male; protease inhibitors.