Detection of Neospora caninum in wild carnivorans in Great Britain

Abstract

Samples of brain and other tissues were collected from 99 ferrets (Mustela furo), 83 red foxes (Vulpes vulpes), 70 European polecats (Mustela putorius), 65 American mink (Neovison vison), 64 Eurasian badgers (Meles meles) and 9 stoats (Mustela erminea), from around Great Britain. DNA was extracted from approximately 1g of tissue and tested by specific nested ITS1 PCR for Neospora caninum. The results from the PCR demonstrated that Neospora specific DNA was detected in all species of wild carnivorans with the exception of the stoats (0/9). Neospora DNA positive samples were detected in: polecats 18.6% (13/70), badgers 10.9% (7/64), ferrets 10.1% (10/99), foxes 4.8% (4/83) and mink 4.6% (3/65). In the badgers N. caninum DNA positive samples were found in brain (n=2), liver (n=2) and neck muscle (n=3). Selected positive ITS1 DNA sequences were submitted to Genbank. Sequence UKwildlife1 (accession number JX857862) was found in two badgers, whilst UKwildlife2 and UKwildlife3 (accession numbers JX857863 and JX857864 respectively) were found in ferrets, all three sequences demonstrated point mutations at a single base, while sequence UKwildlife4 (accession number JX857865) was found in all the species that tested positive and showed complete identity when compared against published reference sequences for: N. caninum (Nc Liverpool isolate, EU564166). Our data shows that almost all the wild carnivoran mammal species tested are intermediate hosts for N. caninum and are therefore capable of acting as reservoirs of infection for other species. These species could also act as useful sentinel species, demonstrating the presence of the parasite in particular geographical and environmental locations.