Effects of early vaccination with Improvac ® on the development and function of reproductive organs of male pigs

Gonadotropin-releasing hormone (GnRH) vaccine (Improvac®) is effective at diminishing boar taint by interfering with testis function. Early pre-pubertal vaccination at 10 and 14 weeks-of-age could be desirable if sufficient and sustained effects could be achieved. Crossbred male pigs (n=24) were randomly assigned to three groups each with eight individuals: an unvaccinated control group, one group vaccinated with Improvac® early at ages 10 and 14 weeks, and a third group vaccinated with Improvac at the standard ages of 16 and 20 weeks. The average age at slaughter was 25 weeks. At slaughter, reductions in testes weight and bulbourethral gland length of vaccinated pigs compared with controls were observed (P