A pilot study comparing the pharmacokinetics of injectable cyanocobalamin and hydroxocobalamin associated with a trace mineral injection in cattle

Injectable vitamin B12 (cobalamin) is traditionally used to prevent or treat vitamin B12 deficiencies in ruminants. Sheep and human studies have demonstrated the superiority of a single dose of hydroxocobalamin (OHB12) over cyanocobalamin (CNB12) in maintaining high levels of cobalamin in plasma and liver. However, limited data are available for cattle. The purpose of this study was to compare the pharmacokinetics of two forms of cobalamin—OHB12 and CNB12—as a single subcutaneous injection of 28 µg/kg BW at the same time of a trace mineral injection in six non‐cobalt/B12‐deficient Holstein‐Friesian steers. Plasma and liver samples were obtained to determine cobalamin concentration after treatment. Cyanocobalamin had lower retention in plasma and liver than OHB12 (p