Applicability of molecular markers to determine parasitic infection origins in the animal trade: a case study from Sarcoptes mites in wildebeest.

The development of non-manipulative molecular tools to determine the origin of parasite infections in the animal trade (if infected before their export or import) is of great interest worldwide for both the animal trade industry and for animal welfare. Molecular tools have a wide range of applications, including forensic identification, wildlife preservation and conservation, veterinary public health protection, and food safety. Nonetheless, genetic markers were not reported to detect the source of infection in the animal trade. In this study we tested the applicability of molecular tools to detect the origin of Sarcoptes mite infection of wildebeest imported by the United Arab Emirate (UAE) from Tanzania. Using one multiplex of seven microsatellite markers and control samples from UAE, Kenya and Italy, we demonstrated the usefulness of the multiplex STR-typing as a molecular tool of pivotal interest to help commercialist, authorities, and conservationists, to identify the geographical origin of parasitic infections.

Temporal stability in the genetic structure of Sarcoptes scabiei under the host-taxon law: empirical evidences from wildlife-derived Sarcoptes mite in Asturias, Spain.

BACKGROUND: Implicitly, parasite molecular studies assume temporal genetic stability. In this study we tested, for the first time to our knowledge, the extent of changes in genetic diversity and structure of Sarcoptes mite populations from Pyrenean chamois (Rupicapra pyrenaica) in Asturias (Spain), using one multiplex of 9 microsatellite markers and Sarcoptes samples from sympatric Pyrenean chamois, red deer (Cervus elaphus), roe deer (Capreolus capreolus) and red fox (Vulpes vulpes). RESULTS: The analysis of an 11-years interval period found little change in the genetic diversity (allelic diversity, and observed and expected heterozygosity). The temporal stability in the genetic diversity was confirmed by population structure analysis, which was not significantly variable over time. Population structure analysis revealed temporal stability in the genetic diversity of Sarcoptes mite under the host-taxon law (herbivore derived- and carnivore derived-Sarcoptes mite) among the sympatric wild animals from Asturias. CONCLUSIONS: The confirmation of parasite temporal genetic stability is of vital interest to allow generalizations to be made, which have further implications regarding the genetic structure, epidemiology and monitoring protocols of the ubiquitous Sarcoptes mite. This could eventually be applied to other parasite species.

Use of western blot to study Microsporum canis antigenic proteins in canine dermatophytosis.

Western blotting was used to describe the Microsporum canis proteins with antigenic activity in dogs with dermatophytosis. Electrophoretic separation of whole fungal strain extract cultured from a cat was performed under denaturing conditions. The proteins were blotted onto nitrocellulose and probed with sera collected from 22 dogs with dermatophytosis (18 M. canis, 3 M. gypseum, 1 Trichophyton mentagrophytes; group A), 20 dogs with skin diseases other than dermatophytosis, and 22 dogs with no clinical cutaneous signs (group B, n = 42). Nine principal IgG-binding proteins with apparent molecular weights of 180, 144, 130, 120, 102, 96, 80, 68, and 48 kD were visualised on group A blots. For these proteins, serological cross-reactivity with different strains of M. canis may be indirectly confirmed, whereas additional proteins were found to react with sera from individual dogs. The proteins visualised in this study may represent diagnostic markers of dermatophyte infection. The proteins should be further evaluated for their role in the cellular immune response of dogs with dermatophytosis.