The effectiveness of Imrovac® in industrial pork production

Keywords: immunocastration; surgical castration; meat parameters; spermatogenesis


The clinical efficacy of the use of immunobiological castration was studied in comparison with boars in which orchidectomy was performed by open method «on a ligature», as well as in non-castrated animals. It was found that the disadvantage of surgical castration is the risk of bleeding, the development of purulent inflammatory process (edges of the surgical wound, scrotal tissues, stump, common vaginal membrane), as well as intra- and postoperative hernias, which are accompanied by prolapse of the omentum, intestines, and bladder. The low incidence of these complications is offset by the high death rate caused by them. A relatively high level of cryptorchidism was established on the farm, among which bilateral was 27.6%. As a result of the use of immunological castration, in comparison with surgical castration, and with non-castrated boars, the average daily gains were increased, the fattening period was reduced and feed costs were reduced against the background of feed conversion increase by 14 – 27%. The use of Improvac® (Pfizer Ltd) led to better assimilation of feed, an increase in the amount of meat on the carcass, in particular, lean meat by 12 – 16%, lumbar depth, the protein content in meat and a decrease of the fat percentage and fat thickness, eliminating specific odor, and reduction in the fattening period, as well as costs for feeding. In particular, compared to non-castrated boars, the weight of chilled half carcasses increased by 1.2 times (P < 0.05). Immunological castration led to atrophy of the testicles: their weight, length and width were smaller compared to non-castrated boars, which again confirms a decrease in the level of boars’ sex hormones. It is important to use Improvac® in breeding boars that have exhausted their potential, eliminating the need to keep them for about three months to reduce their meat and lard smell. Reducing the period of disappearance of the odor of products obtained from boars led to a reduction in the cost of feeding, maintenance, and veterinary care. Production indicators justify the economic feasibility of using immunological castration with Improvac® in order to obtain additional income, given the absence of probable complications associated with the conventional surgical procedure.


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How to Cite
SamoilіukV. V., Bilyi, D. D., Koziy, M. S., Maslikov, S. M., & SpitsinaТ. L. (2021). The effectiveness of Imrovac® in industrial pork production. Theoretical and Applied Veterinary Medicine, 9(1), 3-9.

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