Effects of surgical and chemical castration on growth performance and meat quality of boars
Abstract
Growing animal welfare concerns have intensified the need for effective and humane alternatives to surgical castration for the control of boar taint in pig production. The study investigated the effects of different castration methods on growth performance, physiological status, and meat quality of boars. Surgical castration and chemical sterilization using intratesticular administration of Canophen-B were compared with intact males. Experiments were conducted on Large White boars under controlled feeding and housing conditions in accordance with animal welfare and bioethical standards. In the first experiment, chemically sterilized and intact sexually mature boars showed similar live body weight and average daily gain. Chemical sterilization resulted in a significant reduction in serum testosterone concentration, while hematological parameters remained within physiological reference ranges, indicating no adverse effects on animal health. Sensory evaluation demonstrated that meat and broth obtained from chemically sterilized boars were free of specific odor, whereas samples from intact males exhibited a characteristic odor, particularly in broth. In the second experiment, surgically castrated boars had lower final live body weight compared with chemically sterilized and intact males. Meat yield was higher and fat yield was lower in intact and chemically sterilized boars than in surgically castrated animals. Serum testosterone levels at the end of the fattening period were highest in intact males, intermediate in chemically sterilized boars, and lowest in surgically castrated animals. Hematological indicators in all groups remained within normal physiological limits. Sensory evaluation of cooked meat revealed no statistically significant differences among experimental groups for odor, color, tenderness, taste, texture, or fibrousness. However, broth prepared from chemically sterilized boars showed significantly higher scores for transparency compared with intact males, while other sensory attributes did not differ significantly. The results indicate that chemical sterilization effectively suppresses testosterone synthesis without negatively affecting growth performance, health status, or sensory quality of meat. The absence of boar taint in products obtained from chemically sterilized males suggests that this method can be considered a viable alternative to surgical castration in pig production, combining acceptable meat quality with improved animal welfare.References
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