Which two pathogens are the most common causes of abortion in sheep?

Which two pathogens are the most common causes of abortion in sheep?

• A. Campylobacter fetus (Vibriosis) & Chlamydia psittaci (enzootic abortion of ewes)
• B. Brucella ovis & Listeria monocytogenes
• C. Coxiella burnetii & Toxoplasma gondii
• D. Neospora caninum & Escherichia coli

Answer: (A)

The main idea here is recognizing the infectious culprits most often responsible for abortion in sheep. The two pathogens you’re most likely to see causing abortions across many flocks are Campylobacter fetus (vibriosis) and Chlamydia abortus (enzootic abortion of ewes). Campylobacter fetus fetus tends to cause sporadic abortions in late pregnancy and spreads readily through contaminated feed, water, or environments, with infected animals shedding organisms in feces. Chlamydia abortus drives enzootic abortion of ewes, often presenting as outbreaks around lambing and spreading via contact with placental materials and aborted tissues; vaccines for ewes before lambing are a key preventive measure. While other organisms on the list can cause abortions in sheep, they are less consistently the leading causes in practice, so this pair best represents the most common infectious etiologies you’d expect to encounter.

The main idea here is recognizing the infectious culprits most often responsible for abortion in sheep. The two pathogens you’re most likely to see causing abortions across many flocks are Campylobacter fetus (vibriosis) and Chlamydia abortus (enzootic abortion of ewes). Campylobacter fetus fetus tends to cause sporadic abortions in late pregnancy and spreads readily through contaminated feed, water, or environments, with infected animals shedding organisms in feces. Chlamydia abortus drives enzootic abortion of ewes, often presenting as outbreaks around lambing and spreading via contact with placental materials and aborted tissues; vaccines for ewes before lambing are a key preventive measure. While other organisms on the list can cause abortions in sheep, they are less consistently the leading causes in practice, so this pair best represents the most common infectious etiologies you’d expect to encounter.