In livestock on farms with known C. burnetii activity, which reproductive outcome is commonly observed?

• A. Spontaneous abortions in livestock
• B. Diarrhea in calves
• C. Neonatal convulsions
• D. Hair loss in ewes

Answer: (A)

Coxiella burnetii infection in ruminants most often shows up as reproductive failure, with spontaneous abortions occurring in late pregnancy. The bacteria localize in the placenta and fetal membranes, triggering placentitis and abortion, and the birth materials shed large amounts of the organism into the environment. This pattern—abortion storms and high abortion rates among pregnant animals—is the typical reproductive outcome on farms with known C. burnetii activity. Other options don’t fit the typical disease presentation: diarrhea in calves points to enteric pathogens, neonatal convulsions aren’t a usual feature of this infection, and hair loss in ewes isn’t associated with C. burnetii.