Immunohistochemical study of scrapie in naturally affected sheep in the east of Libya.

Background: The most common natural prion disease that primarily affects sheep and goats is scrapie. It belongs to a group of disorders known as transmissible spongiform encephalopathies, which impact both humans and animals.

Aim: The research is aimed to examine and confirm the presence of scrapie in Libya using immunohistochemistry (IHC) techniques.

Methods: Brain samples were collected from thirty-three sheep older than two years of age showing clinical signs resembling to scrapie during the period between 2018 and 2023, regardless of race or gender. Three animals, six months old, healthy, and without any symptoms, were used as negative controls. Different parts of the brain, including the obex and cerebellum, were taken from each case. The IHC technique used in this study involved staining with monoclonal antibody L42 and DAB (3,3'-diaminobenzidine) as a chromogenic substrate.

Results: The IHC examination showed the expression of prion proteins in brain tissue in twenty-three samples. The staining intensity was markedly observed in the neuronal cell bodies and around blood vessels.

Conclusion: The findings of this study provide evidence that scrapie exists in Libya.