Effects of Supplementation of Chromium, Monensin and Their Combination on Some Blood Metabolites, Liver Enzymes and Insulin in Close-Up Holstein Dairy Cows

In the present study, 30 multiparous close-up Holstein cows (average parity 3.8) were allocated in a completely randomized design with four treatments to evaluate the effect of chromium, monensin and their combination on blood metabolites and liver enzymes. Experimental treatments were: 1) control (no supplementation) 2) monensin (400 mg/d/h) 3) Chromium (0.03 mg/BW0.75) 4) combination of both supplements with similar dosages. Liver enzymes (AST and ALP) as well as the blood metabolites (glucose, BHBA, total protein, albumin) and insulin were evaluated. The results showed that blood parameters except that BHBA, glucose did not affect by treatment (p>0.05). BHBA concentrations in cows received chromium and its combination with monensin reduced before calving (p<0/05). Glucose concentrations was increased in cows supplemented with monensin (p<0/05). In conclusion, the results revealed that dietary combined supplementation of monensin and chromium may have positive affect on metabolism and energy status of multiparous close-up Holstein cows.