Identification of Pathogens Causing Abortion in Sheep: Clinical Patterns

Introduction: Abortion in sheep, a major global economic concern, causes significant losses in livestock industries, particularly in regions reliant on sheep farming. It is often caused by infectious agents like Neospora caninum, Chlamydia abortus, Listeria monocytogenes, Mycoplasma spp., and Brucella spp. These pathogens induce abortions at varying gestational stages with distinct clinical signs, such as placental damage (N. caninum), late-gestation placentitis (C. abortus), or systemic infections with mastitis or lameness (Mycoplasma, Brucella),

Methods: Samples from aborted fetuses, placentas, and maternal tissues in four affected flocks were analyzed. PCR assays targeted N. caninum (Nc-5), C. abortus (omp1), L. monocytogenes (hly), Mycoplasma spp., and Brucella spp., with primer sets validated against reference strains for specificity and sensitivity.

Results: Two flocks tested positive for N. caninum, showing mid-gestation abortions with placental lesions. Two flocks had Mycoplasma spp., linked to late abortions, mastitis, and lameness. No L. monocytogenes was detected, despite some respiratory or neurological signs in ewes.

Conclusion: Diverse pathogens cause sheep abortions, with distinct gestational timing and clinical signs aiding diagnosis. Molecular detection enables rapid pathogen identification, vital for early intervention and preventing disease spread in flocks. Targeted control reduces economic losses. Molecular tools enhance veterinary epidemiology, improving disease management in livestock.