https://www.selleckchem.com/products/avotaciclib-trihydrochloride.html The aim of this study was to compare testicle morpho-functional characteristics in bulls undergoing a single or two immunizations against GnRH. Nelore (Bos taurus indicus) bulls were randomly allocated into three experimental groups G1 (n=12), a single 400 μg dose of anti-GnRH vaccine on day 0; G2 (n=11), a first 400 μg dose of anti-GnRH vaccine on day 0 followed by a second (boost) dose 30 days later; and control group (CG, n=12), 1 mL saline 0.9% at day 0. Every 30 days, from day 0 until slaughter at day 90, the bulls were weighed and underwent testicular biometry, semen collection and analysis, and blood sample collection for testosterone measurement. Immediately after slaughter, the testicles were removed and transport at 15°C to the laboratory for histopathological analysis. There was a decrease in testicular height (P=0.0476), width (P=0.0021), and in scrotal circumference (P=0.0001), after either a single (G1) or two (G2) immunizations against GnRH. Both G1 and G2 had lower testosterone concentrations than CG from day 60 on (P less then 0.01), but in G2, it was also lower than in G1 at day 90 (P=0.0006). All sperm parameters were affected by active immunization against GnRH (P less then 0.05), and in G2, averages were lesser (P less then 0.05) than in G1 from day 60 on. No signs of seminiferous tubule degeneration were found in any sample from the CG, contrasting with 75.0% and 100.0% of the samples from G1 and G2, respectively. In summary, immunocastration affected testicle morpho-functional characteristics in bulls in a time- and dose-dependent way. The metabolomic profile is an essential tool for understanding the physiological processes of biological samples and their changes. In addition, it makes it possible to find new substances with industrial applications or use as drugs. As GC-MS is a very common tool for obtaining the metabolomic profile, a simple and fast method for sample pre