Immunocastration of young and mature boars with Improvac®

The aim of the study: To evaluate the impact of immunocastration by commercial product Improvac® on young and adults, sexually matured boars. The purpose of the study: 1. To evaluate the impact of immunocastration on intensity of grow, overweight and meat quality of young boars. 2. To evaluate the impact of immunocastration on testosterone concentration in blood, on libido, on semen’s quality and on biochemical indicators of adults/sexually matured boars. 3. To evaluate the impact of immunocastration on adults/sexually matured boar’s testicles and accessory sex glands. 4. To evaluate the impact of immunocastration on meat quality of sexually matured animals as well as on amount of indole and skatole in carcass. Conclusions: 1. Immunocastration of young boars with Improvac product on 95th and 138th day of life had an impact on growth intensity, overweight and meat quality. Day overweight of Improvac group boars were 0.24±0.1 kg bigger and on a day of slaughtering they weighted 2.02±3.93kg more in average if compare with surgically castrated boars (P≤0.01). 2. Meat of vaccinated animals was leaner, percentage of muscularity was bigger and carcass quality according to SEUROP classification was higher (P≤0.001), but for separate meat quality parameters immune-castration of boars had no influence (P≥0.05). During current research amounts of indole and skatole found in vaccinated animals‘ fat haven‘t exceed sensible and permissible limits. 3. Immunocastration of mature boars with Improvac product had a negative impact on testosterone concentration in blood, on libido and semen quality (P≤0.05), but there was no impact on biochemical blood indexes (P≥0.05). 2-3 weeks after the first Improvac vaccine injection concentration of testosterone has reached peak and afterwards was declining steadily. Together libido of animals was declining too. Volume of ejaculate, spermatozoa concentration, sperm vitality have lowered and the number of pathological spermatozoa has increased in ejaculate. 4. Immunocastration of mature boars with Improvac product had a negative influence on the size of boars’ testicles and appendage gonads, on testicle tissue morphology too. Testicles of nonvaccinated boars were bigger than of Group A, B and C boars. Group C boars vesicular gland was 62.98% (P≥0.05) and prostate 47.11% (P≥0.05) smaller if compare with control group boars glands. 5. When vaccinating mature boars two times: 8 and 4 weeks till slaughtering there were no changes in testicle tissues found. Vaccination 12 and 8 weeks till slaughtering (Group B boars) has evoked chronic interstitial inflammation of lymphocytes in testicles and triple vaccination 12, 8 and 4 weeks till slaughtering (Group C boars) influenced degenerative processes of testicle tissue. 6. Significant negative impact of mature boars immunocastration with Improvac product was found on skatole concentration in fat samples. Skatole concentration in fat as well as in omentum fat in Groups A, B and C boars was smaller (P≤0.01) if compare with control group boars. Immunocastration of mature boars had no significant influence on indole concentration, on separate meat quality and on colour parameters (P≥0.05)