The Effects of FSH Versus GnRH Vaccination on Growth Performance and Meat Quality of Surgically Castrated Male Growing-Finishing Pigs

Previous studies have demonstrated that follicle-stimulating hormone (FSH) plays a critical role in promoting adipogenesis. Surgical castration results in elevated FSH concentrations in pigs, and is accompanied by reduced feed efficiency. This study aimed to investigate the effects of a novel FSH vaccine comprising FSHβ13AA-tandem-ovalbumin conjugate on growth performance and meat quality in barrows. Twenty-four barrows with initial body weight of 32.54 ± 1.90 kg and 12-week age, were randomly assigned to three groups: Placebo-immunized, GnRH-immunized, and FSH-immunized. At three weeks after booster immunization, the FSH-immunized group exhibited significantly improved feed efficiency compared to GnRH-immunized barrows. Compared to the Placebo-immunized group, GnRH and FSH vaccination reduced average backfat thickness by 0.90% and 4.55%, abdominal fat weight by 3.49% and 10.56%, and abdominal fat percentage by 4.09% and 11.95%, respectively. Moreover, the FSH-immunized group showed a significant increase in liver weight relative to the Placebo-immunized group. In addition, compared with the control group, at slaughter FSH vaccination significantly increased muscle pH at 45 min, drip loss at 24 h, and shear force (p < 0.05). These results demonstrate that active immunization against FSH in barrows can enhance feed efficiency and reduce adiposity, as well as influence the meat quality.