Effect of immunocastration in group-housed commercial fattening pigs on reproductive organs, malodorous compounds, carcass and meat quality

In the present study, the effect of immunocastration on carcass traits, meat quality, reproductive organs development, and boar taint compounds was investigated. Male piglets (50% Duroc crosses) were randomly assigned to three treatment groups: entire males (EM; n = 19), surgical castrates (SC; n = 20) and immunocastrates (IC, vaccinated with Improvac® at the age of 79 and 142 days; n = 21). Pigs were fed ad libitum and weighed at the time of first and second vaccination and before slaughter (176 days of age). No differences between treatment groups were detected for carcass weight. In the case of backfat thickness, carcass lean meat content, and belly leanness score, IC were intermediate between EM (the leanest) and SC (the fattest), differing (P < 0.05) from both control groups. Regarding loin eye fat area, neck intermuscular fatness, ham leanness, and leaf fat weight, IC were similar to EM and were less fat than SC (P < 0.01). IC had lower intramuscular fat than SC (P < 0.01) and higher average pH 24 than both EM and SC (P < 0.01), resulting in darker colour. IC also demonstrated lower drip loss than EM (P < 0.05). Immunocastration caused a significant reduction of reproductive organs and concentrations of boar taint compounds (P < 0.01) which were comparable with the levels observed for SC.