Disease control in wild ungulate populations is one of the major challenges in wildlife management. The global increase in temperature, translocations of wild and domesticated animals, and the increased contact between wildlife and livestock, are factors predicted to increase the risk of emergence and/or re-emergence of disease in wild populations. In Europe, as a result of environmental change, the risk of infection of wild ungulates may be exacerbated by substantial increases in numbers and a deterioration in body condition which is associated with reduced immune competence. Therefore, studies assessing the resilience of ungulate populations are vital, in particular, with the recent detection of Chronic Wasting Disease (CWD) in deer populations of northern Europe and the concerns regarding its potential spread to deer populations in the UK.
The Major Histocompatibility Complex (MHC) is a region of the vertebrate genome which includes families of highly variable genes that play central roles in immune defence. High levels of allelic diversity at MHC loci are generally associated with healthy outbred populations. These features provide useful genetic markers with which to estimate resilience to pathogens in wild ungulate populations. Studies of MHC variation in European deer populations are scarce and have focused on single populations or populations separated by large distances. A recently published study, funded by the British Deer Society, assessed MHC diversity in Scottish red deer at a geographical scale relevant for the management of this species. To date, this study represents the most thorough assessment of MHC variation in populations of red deer in Europe. Importantly, this study indicated that MHC class II DRB variation was high, with 25 alleles identified from 48 highland red deer. This study also showed that populations on either side of the Great Glen are genetically differentiated when population structure is estimated using microsatellite markers. However, this marked genetic differentiation between populations at either side was not appreciated when population structure was estimated with the MHC data. As pathogen diversity is thought to provide the selection pressure that maintains allelic diversity within a population, these results suggest that red deer populations in the study areas are likely to be challenged by a similar array of pathogens. This study represents the first platform for a large-scale project aiming to build an immunogenetic map of red deer populations across Scotland with the view to inform future management strategies of this iconic and economically important species.
Dr Sílvia Pérez-Espona
Royal (Dick) School of Veterinary Studies and The Roslin Institute
Details of the publication can be found below. For any questions and queries, you can email silvia.perez-espona@ed.ac.uk
Pérez-Espona S., Goodall-Copestake W.P., Savirina A., Bobovikova J., Molina-Rubio C., Pérez-Barbería F.J. (2019). First assessment of MHC variation in wild Scottish red deer populations. European Journal of Wildlife Research 65:22. https://doi.org/10.1007/s10344-019-1254-x