Causes of abortion in Iranian sheep flocks and associated risk factors

Abstract

Abortion is a major issue in sheep husbandry. It can result in significant economic losses and a severe public health risk. This survey assessed the infectious and non-infectious causes of abortion in Iranian sheep flocks and determined the main risk factors. In this cross-sectional survey, causes of abortion were evaluated in 757 sheep flocks, and risk factors were analysed. A checklist containing general animal information for each abortion outbreak evaluated was filled in. Data were analysed using univariate tests and multivariable binary logistic regression analysis. In this sense, parity, gestational age of the aborted fetus, vaccination protocol, mineral supplementation and history of stillbirth showed significant associations with abortion. Infectious agents such as Coxiella burnetti (22.7%), Chlamydia abortus (12.3%) and Brucella melitensis (10.4%) were the most frequently isolated in the investigated flocks, with more than 2% of abortion rates. On the other hand, non-infectious agents such as trauma, pregnancy toxaemia and vitamin E/Se deficiency were involved in those flocks with low abortion rates (less than 10%). Results revealed multiple causes of abortion outbreaks among Iranian sheep flocks, which need careful investigation to identify possible aetiology and risk factors. Further studies are necessary to evaluate if these factors are similar to other countries in the same region.

Knowledge, attitudes and practices of sheep owners regarding abortion in Northern Tunisia

“…These vaccinations are performed yearly as national campaigns by private veterinarians that are paid by the Tunisian Ministry of Agriculture. The vaccination against sheep abortion is an essential part of a good health management system and a key requirement in intensive systems (Esmaeili et al., 2022). This lack of knowledge might be due to a huge gap of knowledge of these diseases by Tunisian animal health professionals.…”

“…On the other hand, indirect costs are high but paradoxically underestimated by both sheep owners and animal health specialists. These costs are related to an increase in lambing intervals with all its consequences, including reduction in lamb production, increase in food expenses and increase of veterinary fees (Esmaeili et al., 2022). Furthermore, abortion in sheep can have great impact on public health as several sheep abortive causative agents are zoonotic such as Brucella spp., Salmonella spp., Campylobacter spp., Chlamydia abortus , Listeria monocytogenes , Coxiella burnetii and Toxoplasma gondii .…”