Determination of the effect of a monensin capsule (continuous-release capsules) on metabolic parameters in transition dairy cows

Abstract

Monensin is an ionophore antibiotic that changes the population of rumen bacteria. The aim of this study was to determine the effects of a monensin controlled-release capsule administered 3 weeks before calving on blood metabolites (serum beta-hydroxybutiric acid (BHBA), cholesterol (CHOL), urea, creatinine (CREA), gamma glutamyl transferase (GGT), aspartate aminotransferase (AST), total protein (TP), phosphorus (P), magnesium (Mg+), calcium (Ca++), glucose (GLU) and plasma non-esterified fatty acids (NEFA) concentration) and milk yield before and after calving. A total of 50 Holstein-Friesian cows were selected from the same flock. Blood samples were taken 3 weeks before the expected calving date and during weeks 1, 2, 4, 6, and 8 after calving. The cows were divided into two groups: a study group (Group M, n = 40) and a control group (Group C, n = 10). Group M received orally a cylindrical device (Kexxtone, ELANCO Animal Health, Guelph, ON, Canada), and group C received no treatment. BHBA and NEFA were lower (P < 0.05) in group M compared with group C in weeks 6 and 8 after calving. GLU was higher (P < 0.05) in group M compared with group C in week 4 after calving. Urea was higher (P < 0.05) in group M compared with group C in week 1 after calving. There was no statistically significant difference (P <0.05) between the two groups in milk yields. Although milk yield was similar in both groups, the changes in the concentrations of BHBA, NEFA, GLU and urea show that a monensin CRC could be used as a glycogenic precursor.