Inbreeding and squirrelpox virus
Melissa Marr
A new study has started at the Insitute of Zoology, London on whether inbreeding affects the disease status of squirrelpox virus in red squirrels.
Does inbreeding affect the disease status of red squirrels (Sciurus vulgaris) with respect to squirrelpox virus (SQPV)?
Project duration: 12 months, starting June 2009.
Background: From its previous status as widespread and abundant throughout the U.K, the red squirrel has now suffered a dramatic decline over the last 100 years. This has been coupled with extensive local extinctions and, in England and Wales, red squirrels now exist only in isolated populations. Red squirrel populations remain in decline with the causal factors appearing to be infectious disease and competition for juvenile recruitment with the introduced grey squirrel. There is good evidence that the grey squirrel is the reservoir of the squirrelpox virus (SQPV) – a lethal virus to red squirrels and one which is considered to be a significant threat to the conservation of red squirrels in the U.K.
Isolated populations of red squirrels have been shown to have low within population genetic diversity. This inbreeding effect has been linked to susceptibility to pathogens in other species, and therefore individual red squirrels showing loss of heterozygosity may have increased susceptibility to SQPV.
Project Summary: This project aims to investigate the relationship between individual genetic diversity and susceptibility to squirrelpox virus by:
- Identifying, by post-mortem examination and electron microscopy, individuals infected with SQPV.
- Assessing the heterozygosity of individuals by microsatellite typing at specific loci.
- To assess whether inbreeding influences the adrenal gland size in individual red squirrels, which would suggest that heterozygosity may affect immune function.
We hope the results of this project will serve to inform decision making in red squirrel conservation and help in the provision of effective conservation measures to ensure genetically viable, self-sustaining populations.
This project is being funded by the Peoples Trust for Endangered Species Mammal Internship Grant 2009 and will be undertaken at the Institute of Zoology under the supervision of Dr Tony Sainsbury and Dr Bill Jordan.
For further information please contact Melissa Marr, Research Intern, Zoological Society of London, Regents Park, London, NW1 4RY.