Published online by Cambridge University Press: 22 November 2017
The antibiotic Actaplanin is a complex of glycopeptide compounds produced by Actinoplanes missourrensis. When included in feed as a performance enhancer it has been shown to increase milk production of dairy cows (McGuffey et al. 1983). Actaplanin is associated with reduced proportions of acetate and increased proportions of propionate in rumen fluid and a depression in milk fat proportion may result (Clapperton et al. 1987). The aim of the trial reported here was to monitor the effects of feeding 960 mg Actaplanin/head/d to dairy cows throughout two successive lactations.