What are the two most common causes of abortions in sheep?

The two most common causes of abortions in sheep are Campylobacter fetus and Chlamydia psittaci. Campylobacter fetus, specifically the subspecies venerealis, is known to cause early term abortions and is often transmitted sexually. Chlamydia psittaci can lead to late-term abortions and is also associated with a variety of other health issues in sheep, including enzootic abortion. These pathogens can pose significant reproductive challenges in sheep farming, making prevention and control vital for flock health.

This answer stands strong due to the prevalence of these pathogens in sheep populations and their significant impact on reproductive performance. The other options include causes of abortions, but they are not as commonly associated with sheep compared to Campylobacter and Chlamydia. Understanding the common causes helps in developing management strategies and interventions to reduce reproductive losses in sheep.