Effects of increasing monensin doses on performance of mid-lactating Holstein cows

Abstract

The objective of this study was to determine the effect of increasing monensin doses on intake, nutrient digestion, ruminal fermentation, nitrogen balance, blood metabolites, milk yield and composition of lactating dairy cows. Twelve Holstein cows (135 ± DIM; 580 ± kg of BW) were assigned to three 4 × 4 Latin square design, with 21-d periods. Cows were randomly assigned within each square to receive one of the following treatments: Control (C): 0 mg kg −1 DM of monensin; Monensin 12 (M12): 12 mg kg −1 DM of monensin; Monensin 24 (M24): 24 mg kg −1 DM of monensin and Monensin 48 (M48): 48 mg kg −1 DM of monensin. Monensin had quadratic effect on intake of dry matter. Apparent total-tract digestibility of DM were similar between treatments; however, digestibility of CP increased. Monensin had no effect on ruminal pH, NH 3 concentration, but propionate increased by monensin. Blood urea nitrogen was increased linearly by monensin. There was a quadratic effect of monensin on N intake. Monensin had a quadratic effect on milk yield, whereas 3.5% FCM was decreased linearly. These results suggest that monensin improves performance of mid-lactating dairy cows fed corn silage-based diet, and monensin can be added up to 24 mg/kg of DM diets. ARTICLE HISTORY

Effects of monensin supplementation on lactation performance of dairy cows: a systematic review and dose–response meta‑analysis

“…Similar to this study, inclusion of low to moderate levels of monensin in the diets of dairy cows was found to decrease milk fat yield and milk fat percentage in several previous studies 23 , 32 , 33 , 37 , 38 . Interestingly, milk fat yield remained unchanged at moderate to high monensin inclusion, and milk fat percentage remained unchanged or decreased 23 , 35 , 36 . This meta-analysis confirms the results of the meta-analysis by Duffield et al 10 , who reported that dietary monensin supplementation resulted in a lower milk fat percentage.…”

“…In the leave-one-out analysis, studies No. 4 23 , 11 25 , 14 26 , and 27 27 were found to be influential. Exclusion of these studies from the analysis did not change the statistical significance of the original model, but did change the estimated effect sizes.…”

“…Based on leave-one-out analysis, study No. 5 23 was a highly influential study. Their exclusion changed the model result; all doses of monensin addition resulted in increased milk protein yield.…”

Effects of mineral supplementation on cattle performance when grazed mature wheat

“…In addition, the current study also showed a lower LWG than observed in some earlier studies, 0.7 kg/day/heifer grazed vegetative wheat in Cheng et al (2016) and 0.7-0.9 kg/day/heifer grazed herbal pasture in Cheng et al (2017aCheng et al ( , 2017b. Previous studies indicated that monensin (Santos et al 2019) and Zeolite (Khachlouf et al 2019) supplementation can improve the DM and CP intake in similar situations.…”

“…Monensin (Santos et al 2019) and Zeolite (Khachlouf et al 2019) have been extensively used to manipulate nitrogen (N) intake and mineral status in dairy cows. Supplementation of livestock grazing wheat with Na and Mg can increase sheep live weight gain (LWG) by up to 60% (Mulholland and Coombe 1979;Rowe et al 1989;Dove and Mcmullen 2009).…”