Impact of environmental factors on milk β-hydroxybutyric acid and acetone levels in Holstein cattle associated with production traits

摘要: The objective of this study was to estimate the environmental factors affecting milk β-hydroxybutyric acid (BHBA) and acetone (Ac) concentrations in Holstein cattle. A total 264,221 test-day records collected from Korea Animal Improvement Association (KAIA) during period 2012 2014 were used study. Analysis variance (ANOVA) performed determine significantly ketone body concentrations. Parameters considered model season test, calving, parity, lactation stage, collecting time (AM PM). According ANOVA, R² for BHBA Ac 0.5226 0.4961, respectively. ‘Season test’ showed a considerable influence on concentration. Least square (LS) means lowest (39.04 μM) winter while it increased up 62.91 μM summer. But concentration did not change along with ‘season test’. high at first low around second then gradually increased. Cows milked morning had lower mean (48.49 121.69 μM, respectively) comparison those evening (53.46 130.42 respectively). LS slightly over parities. These results suggest that proper maintenance collection, herd management programs, evaluation levels should be efficient resistance ketosis.