Management Approaches to Reducing or Eliminating Mycoplasma Mastitis in a Dairy Herd

What Has Been Working and Not Working

Abstract

Mycoplasma spp can cause mastitis, arthritis, pneumonia, and metritis in dairy cattle. Progress in control of Mycoplasma spp mastitis, including any management changes made, was evaluated in Utah dairy herds approximately one year after diagnosis on farms that had participated in a mycoplasma prevalence study. Using a questionnaire developed at Utah State University, dairy producers and key management personnel on 10 previously mycoplasma-positive dairy farms in Utah were interviewed. Three farms had evidence that no mycoplasmal cows remained, four had mycoplasma still present, and three were of unknown mycoplasma status. Farms that cultured milk from all clinical mastitis cases for mycoplasma included all of the farms with no further evidence of mycoplasma in cows, and farms with very low prevalence remaining. Of farms that used only bulk-tank monitoring for mycoplasma at the time of the second follow-up survey, all but one were still positive or had unknown status; the only farm using bulk-tank monitoring that was apparently free of mycoplasma had cultured all clinical mastitis cases for several months after diagnosis in the herd, and sold all mycoplasmal cows found. All herds increased lactating cow numbers, and six had decreased bulk-tank milk somatic cell count (SCC). Decreased or eliminated mycoplasma mastitis was associated with approximately 1% less of the herd per month contracting clinical mastitis, and even further reduced treatment for mastitis. Mycoplasma mastitis persisting in dairy herds was associated with observing clinical mastitis moving from one quarter to another, adult cows with droopy ears and nonresponsive respiratory disease in calves.