Detección de anticuerpos anti-Mycobacterium avium subsp. paratuberculosis (MAP) en venados silvestres en Colombia / Detection of anti-Mycobacterium aviumsubsp. paratuberculosis antibodies in wild deer in Colombia

RESUMEN Objetivo. Determinar la presencia de anticuerpos anti-Mycobacterium avium subsp. paratuberculosis (MAP) en venados de cola blanca (Odocoileus virginianus) y venados de páramo (Mazama rufína), capturados en las regiones de la Orinoquía y el Caribe en Colombia. Materiales y métodos. Un total de 44 muestras de suero sanguíneo de venados de las especies M. rufína y O. virginianus fueron colectadas en condiciones de campo entre 2014 y 2016. Se utilizó un kit comercial de ELISA para la detección de anticuerpos anti-MAP. Un animal se consideró positivo a ELISA cuando la relación muestra-positivo (S/P%) fue > 0.4, según lo recomendado por el fabricante. Resultados. El 50% (22/44) de los animales muestreados resultaron positivos, lo que corresponde a 10 hembras y 12 machos. Un 81.8% (18/22) y un 77.3% (17/22) de estos animales seropositivos fueron capturados en la región de la Orinoquía y fueron reportados como adultos, respectivamente. Conclusiones. No se sabe cómo o cuándo se introdujo MAP en la población de ciervos colombianos en las regiones de estudio. La hipótesis más plausible para explicar la presencia de anticuerpos anti-MAP en estas poblaciones silvestres es la transmisión por contacto con el ganado bovino infectado, ya que en ambas regiones estas especies comparten pasturas. Este es el primer estudio en explorar la infección por MAP en animales silvestres en Colombia. Estos hallazgos respaldan la necesidad de realizar más estudios utilizando técnicas de diagnóstico directo, y aproximaciones investigativas que permitan la definición de vínculos en la dinámica de la infección entre mamíferos silvestres y domésticos en Colombia.

ABSTRACT Objective. To determine the presence of anti-Mycobacterium avium subsp. paratuberculosis (MAP) antibodies in white-tailed deer (Odocoileus virginianus) and red brocket deer (Mazama rufína), captured in the Orinoquía and Caribbean regions in Colombia. Materials and methods. A total of 44 blood serum samples from deer of species M. rufina and O. virginianus were collected under field conditions between 2014 and 2016. An ELISA commercial kit was used to detect anti-MAP antibodies. An animal was considered ELISA-positive at a sample-to-positive ratio (S/P%) of > 0.4, as recommended by the manufacturer. Results. The 50% (22/44) of the animals were positive, corresponding to 10 females and 12 males. An 81.8% (18/22) and 77.3% (17/22) of these seropositive animals were captured in the Orinoquía region and were reported as adults, respectively. Conclusions. It is not known how or when MAP was introduced in the Colombian deer population in the study regions. The most plausible hypothesis to explain the presence of antibodies against MAP in these wild populations is transmission by contact with infected bovine cattle since, in both regions, these species share pastures. This is the first study to explore MAP infection in wild animals in Colombia. These findings support the need for further studies using different direct diagnostic techniques and research approaches that allow the definition of links in the infection dynamics between wild and domestic mammals in Colombia.

Genetic variability of the prion protein gene (PRNP) in wild ruminants from Italy and Scotland

The genetics of the prion protein gene (PRNP) play a crucial role in determining the relative susceptibility to transmissible spongiform encephalopathies (TSEs) in several mammalian species. To determine the PRNP gene variability in European red deer (Cervus elaphus), roe deer (Capreolus capreolus) and chamois (Rupicapra rupicapra), the PRNP open reading frame from 715 samples was analysed to reveal a total of ten single nucleotide polymorphisms (SNPs). In red deer, SNPs were found in codons 15, 21, 59, 78, 79, 98, 136, 168 and 226. These polymorphisms give rise to 12 haplotypes, and one of which is identical to the PRNP of American wapiti (Rocky Mountain elk, Cervus elaphus nelsoni). One silent mutation at codon 119 was detected in chamois and no SNPs were found in roe deer. This analysis confirmed that European wild ruminants have a PRNP genetic background that is compatible with TSE susceptibility, including chronic wasting disease.