Immunocastration and its effects on carcass and meat traits of male pigs

Abstract

To compose the experiment, 160 male Topgen pigs - 80 surgically castrated (treatment 1) and 80 immunocastrated (treatment 2) - were randomly selected from a commercial swine farm at the moment of slaughter. Surgical castration was performed when the animals were seven days of age and immunocastration was performed by administering two doses (2 mL each) of immunocastration vaccine (analogue of GnRF linked to a carrier protein, development of anti-GnRF antibodies, 200 mg of a GnRF-protein conjugate/mL) when they were 104 and 132 days of age. Animals from both treatments were maintained in masonry stalls, where they received water and ad libitum diet (the same feed for both groups). The animals were slaughtered at 160 days of age, and the length and width of the testicles of immunocastrated animals were evaluated, along with the degree and number of carcass lesions, carcass traits and meat quality of both treatments. The means of these measurements were calculated and compared by Student´s t-test. For the immunocastrated treatment, Pearson´s correlation coefficients were also calculated for testicle length and width with backfat thickness. Approximately 80% of the immunocastrated animals had testicle widths of 11 cm or less. Immunocastrated animals showed higher degrees of lesions, pH (initial and 8 hours), hue, muscle depth and loin eye area and lower brightness, redness, chroma and backfat thickness than the surgically castrated animals. The correlation between testicle length and width with backfat thickness was inverse. Immunocastration can be an alternative to improve the proportion of lean meat (longissimus thoracis) instead of fat (backfat thickness) leading to better carcass and meat quality, since fat has become undesirable from a nutritional point of view in swine.

Influence of Immunocastration and Diet on Meat and Fat Quality of Heavy Female and Male Pigs

“…In the literature, the effect of the type of castration on color traits is not unanimous. Some reports [ 41 , 46 , 47 ] did not find differences between SCM and IM in any color trait but others [ 48 , 49 , 50 ] showed, as in the present work, that meat from IM presented lower L * value. Daza et al [ 36 ], Andreo et al [ 50 ] and Seiquer et al [ 42 ] observed that IM presented lower a * and values, and Škrlep et al [ 44 ] observed the opposite effect.…”

“…Some reports [ 41 , 46 , 47 ] did not find differences between SCM and IM in any color trait but others [ 48 , 49 , 50 ] showed, as in the present work, that meat from IM presented lower L * value. Daza et al [ 36 ], Andreo et al [ 50 ] and Seiquer et al [ 42 ] observed that IM presented lower a * and values, and Škrlep et al [ 44 ] observed the opposite effect. Different genetic types, pre-slaughter handling and conditions of data collection could contribute to pork color [ 51 ], generating differences unrelated to animal husbandry.…”

Efficiency of the anti-GnRH vaccine for castration of lambs intended for finishing in pastures

“…In an experiment with immunocastrated pigs, Andreo et al (2018) affirmed that there is individual variation in the antibody titers generated by the vaccine among animals due to factors such as genetics, nutritional status, age and stress at the time of application, which explains the fact that in the present study animals have different responses to treatment. Gogić et al (2019) with swine, which found a reduction of 28.9 to 54.4% in the testis volumes and weights of immunocastrated animals compared to control animals.…”