Ovine scrapie: priorities and importance

Area of Science:

• Veterinary Medicine
• Prion Diseases
• Animal Epidemiology

Background:

• Ovine and caprine scrapie are animal transmissible spongiform encephalopathies (TSEs) with significant economic and public health implications.
• Scrapie strains have implications for TSE development in various animal species, including deer and cattle, with potential links to bovine spongiform encephalopathy (BSE).
• Domesticated sheep are considered a key reservoir for animal TSEs, with potential transmission routes including contaminated feed, and scrapie has zoonotic potential, as evidenced by variant Creutzfeldt-Jakob disease in humans.

Purpose of the Study:

• To investigate the genetic susceptibility of Slovak Valachian sheep to scrapie.
• To identify specific prion protein (PrP) genotypes associated with scrapie in this breed.
• To inform breeding strategies for enhancing scrapie resistance in sheep populations.

Main Methods:

• Genotyping of Valachian rams to determine PrP genotypes.
• Analysis of VRQ and ARQ alleles associated with scrapie susceptibility.
• Comparative analysis with scrapie strains from different geographical regions.

Main Results:

• The PrP genotype of Valachian rams includes VRQ and ARQ alleles, which are known to confer susceptibility to scrapie.
• These findings highlight the genetic basis of scrapie susceptibility within this specific sheep breed.
• The identified alleles are crucial for understanding scrapie epidemiology in sheep.

Conclusions:

• Domesticated sheep are a critical reservoir for animal TSEs, necessitating effective surveillance and control measures.
• Eliminating scrapie from ruminant populations is vital to prevent prion entry into the human food chain.
• Selective breeding based on PrP genotype, such as identifying and managing VRQ and ARQ alleles in Valachian sheep, is a key strategy for developing scrapie-resistant livestock.