Causes of abortion in Iranian sheep flocks and associated risk factors

Causes of abortion in Iranian goat herds and associated risk factors

Abortion imposes a substantial economic burden on the global small ruminant industry, not only reducing herd productivity but also contributing to the spread of zoonotic diseases. This study examines the primary factors associated with abortion, both infectious and non-infectious, in 623 goat herds across Iran. A comprehensive evaluation was performed, incorporating herd history, laboratory results, and statistical analyses using univariate tests and multivariable binary logistic regression. Key findings revealed significant associations with abortion, including previous abortion history, gestational age of the aborted foetus, routine veterinary visits, mineral supplementation, and vaccination practices. Non-infectious factors, such as pregnancy toxemia, goiter, and deficiencies in vitamin E/selenium, were identified in herds with a low abortion prevalence (<10 %). Among the 623 herds studied, 277 (44.5 %) exhibited an abortion prevalence below 2 %, considered within normal limits, while the remaining 346 herds (55.5 %) experienced pathological abortion rates exceeding 2 %. The definitive cause of abortion was determined in 227 of the 346 abortion outbreaks analysed, accounting for 65.6 % of the cases. Infectious agents were identified in 40.7 % of the herds with abortion rates exceeding 2 %, with Brucella melitensis (9.5 %), Chlamydia abortus (7.8 %), and Coxiella burnetii (5.2 %) being the most prevalent pathogens. Multivariable binary logistic regression analysis revealed significant associations between abortion and several factors, including birth (OR=2.01, 95 % CI: 1.05-3.89, P=0.036), previous abortion history (OR=14.5, 95 % CI: 6.01-37.3, P<0.001), gestational age of the aborted foetus (OR=3.07, 95 % CI: 1.63-5.89, P<0.001), routine veterinary visits (OR=0.16, 95 % CI: 0.09-0.27, P<0.001), vaccination (OR=0.25, 95 % CI: 0.11-0.53, P<0.001), and mineral supplementation (OR=0.36, 95 % CI: 0.21-0.62, P<0.001). These findings underscore the diverse causes of abortion in Iranian goat herds, emphasizing the need to improve farmer awareness and access to commercial vaccines targeting infectious abortion agents to enhance herd productivity.

A six-year epidemiological study of selected zoonotic abortifacient agents in ovine and caprine foetuses in Türkiye

Abortion is one of the major threats to the livestock industry, and it also poses significant threats to public health since some of the abortifacient agents are considered zoonotic. Chlamydia abortus (C. abortus), Coxiella burnetii (C. burnetii), Listeria monocytogenes (L. monocytogenes), and Cache Valley virus (CVV) are recognized as important zoonotic and abortifacient agents of reproductive failure in small ruminants. This study determined the prevalence of these agents in ovine and caprine foetuses in Türkiye. A total of 1 226 foetuses were collected from the sheep (n = 1 144) and goats (n = 82) from different flocks between 2012 and 2017. Molecular detection methods were used to detect C. abortus, C. burnetii, and L. monocytogenes DNA and CVV RNA in aborted foetuses. In this study, C. abortus was the most prevalent abortifacient agent among the investigated ovine (264/1144) and caprine (12/82) foetuses, followed by C. burnetii with a frequency of 2.8% (32/1144) and 8.5% (7/82) in ovine and caprine foetuses, respectively. L. monocytogenes DNA was detected in 28 (2.4%) and 2 (2.4%) of the ovine and caprine foetuses, respectively. However, CVV RNA was not detected. Although the predominant mixed infection was C. abortus and C. burnetii, mixed infection of C. abortus and L. monocytogenes, and C. burnetii and L. monocytogenes were also found. The information presented in this study contributes to the understanding of the roles of C. abortus, C. burnetii, L. monocytogenes, and CVV in abortions in small ruminants, and could be beneficial for developing more effective control strategies.

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

BACKGROUND

Abortion in ewes causes high economic losses and represents a threat for human health due to abortive zoonotic pathogens.

OBJECTIVE

The present study aimed to assess the knowledge, attitudes and practices (KAP) among sheep owners in the northern Tunisia regarding ewes' abortions.

METHODS

Between February 2021 and May 2022, a structured questionnaire containing both close and open-ended questions was applied to 120 sheep owners in northern Tunisia. The data collected were analysed by chi-square test using Epi info 6 software.

RESULTS

The majority (75%) of participants reported a history of abortion in their sheep flocks. Sheep owners thought that the most frequent cause of abortion was physical factors, such as trauma, climate and stress (60% ± 5.5%; 48/80), followed by toxicity (15% ± 4%; 12/80), metabolic and nutritional conditions (12.5% ± 3.7%; 10/80), vaccination (5% ± 2.4%; 4/80) and infectious causes (7.5% ± 2.9%; 6/80) (p < 0.001). The majority of animal owners reported that abortions occurred mainly during autumn (39.6% ± 5%; 38/96), followed by summer (27% ± 4.5%; 26/96), winter (23% ± 4.3%; 22/96) and spring (10.4% ± 3.1%; 10/96) (p < 0.001). Approximately, half (45.8% ± 5%; 55/120) of interviewed farmers would not take any action if an abortion occurred. Half of the interviewed farmers (50.5% ± 5.1%; 48/95) did not apply any preventive measures when manipulating aborted ewes, and most of the sheep owners (77.3% ± 3.8%; 92/119) did not know that aborted ewes could transmit zoonotic pathogens.

CONCLUSIONS

Our survey concluded that sheep owners in Northern Tunisia had poor knowledge and attitudes as well as applied limited actions concerning several health aspects related to abortion. Education programmes should be established in order to improve Tunisian sheep owners' KAP regarding abortion.

Molecular detection of bacterial zoonotic abortive agents from ruminants in Turkey

Abortions in cattle and sheep are one of the major causes of economic losses worldwide. Brucella spp. are the most common infectious agent associated with these abortions. However, abortions caused by bacteria such as Listeria spp., Leptospira spp., Campylobacter spp. and Mycoplasma spp. are usually overlooked due to their sporadic nature and their status as non-priority abortion agents. In our study, we investigated the bacteria associated with abortion cases in cattle and sheep using PCR. For this purpose, we collected vaginal swab samples (n: 110) of aborted cattle and sheep, as well as stomach content samples (n: 69) of aborted calves and lambs from various cities in Turkey. The samples were analysed by bacteria-specific PCR to detect Campylobacter fetus, Leptospira spp., Listeria spp., Mycoplasma spp., and Yersinia spp. PCR analyses revealed that the investigated bacterial agents were present in 18.85% and 19.3% of the cattle and sheep samples, respectively, with an overall percentage of 18.99%. While the overall positivity rate for C. fetus, Leptospira spp., and Mycoplasma spp. was 2.79%, 10.06%, and 4.47%, respectively, the positivity rate for co-infection with Leptospira spp. and C. fetus was 1.68%. All samples were found to be negative for Yersinia spp. and Listeria spp. The high C. fetus positivity rate detected in sheep and in the stomach contents was statistically significant (p < 0.05). However, the difference in positivity rates between the cities, hosts, co-infections and causative agents was statistically insignificant (p > 0.05). This study provides preliminary data on the significant involvement of C. fetus, Leptospira spp. and Mycoplasma spp. in cattle and sheep abortions in Turkey indicating that they should not be overlooked in diagnosis. In addition, further research is needed to investigate the zoonotic potential of these pathogens for public health in Turkey.