Locally Grown Crops and Immunocastration in Fattening Heavy Pigs: Effects on Performance and Welfare

Abstract

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.

Effects of Field Pea Diet and Immunocastration in Heavy Pigs on Fresh Pork and Dry-Cured Ham

“…2), in addition to dietary pea inclusion, the effect of castration type in male pigs (surgical, CM vs. immunocastration, IM) was evaluated during the same fattening period. In this case, as mentioned, the growth performances were shown in an earlier manuscript [14], and herein, only the amount of fat and FA composition of loins and weight losses of dry-cured hams are shown. Not all measurements were conducted on all animals in the two experiments, Exp.…”

“…The CM pigs were surgically castrated during the first week of age, whereas the IM pigs were kept as entire male pigs until they reached 20 weeks of age. At this point, they were vaccinated with the first dose of the anti-GnRH vaccine, followed by another dose at 24 weeks of age, using the same procedures as described in Argemí-Armengol et al [14].…”

“…The level of inclusion of field peas was gradually increased to adapt to the pig digestive tract capacity to stand with potential dietary anti-nutritional factors. Accordingly, the trypsin inhibitor activity was previously analyzed and kept within safety limits [14]. Diets were formulated to be isonitrogenous, isoenergetic, and isoamino acidic for the first limiting indispensable amino acids (AA).…”

“…The effects of partial or complete replacement of all the soybean meal with field peas in diets of IF and IM on carcass performance, carcass quality, and pork FA composition, as well as the potential alteration of feeding patterns, have not been studied. In a companion paper, on-farm performances and feeding behavior were evaluated in male pigs but not in female pigs [14]. Hence, it would also be reasonable to study how feeding strategies would affect the performances and behavior of IF in order to disentangle potential explanatory variables of their fatness content and composition.…”

A Preliminary Evaluation of Sex and Dietary Field Pea Effects on Sensory Characteristics of Dry-Cured Loins

“…Škrlep et al [ 21 ] and Čandek-Potokar et al [ 22 ] reported the same effect on sensorial hardness in dry-cured meat between surgical castrated male pigs and immunocastrated male pigs (immunocastrated female pigs were not studied). The differences in the amount of feed intake and lipogenic activity may explain the varying effects between sexes reported in another previous paper [ 23 ]. The study also found that IM pigs had a higher average daily feed intake but a lower feed conversion rate than CM pigs.…”