Genetic analysis and management in small populations: the Asturcon pony as an example

Abstract

Geneticists are faced with various problems when managing small naturalpopulations (e.g. high inbreeding, loss of economic value). We proposehere the management of a small population through the example of theAsturcon (a Celtic pony population) by examining two sources ofinformation: a studbook created in 1981 and the polymorphism of tenmicrosatellite markers chosen according to the recommendations of ISAG(International Society of Animal Genetics). This information allows usto estimate several genetic parameters useful in assessing the geneticsituation of the population in order to propose conservationstrategies. Results show the reliability of molecular information inpopulations where no studbook exists. Overall inbreeding value (F) andfixation index (F-IT) are moderate (F = 0.027; F-IT = 0.056), effectivenumber of founders is small (n = 22), and the population is dividedinto three distinct groups (F-ST = 0.078; P < 0.001). The molecularheterozygosity (H-M = 71.2%) computed in a random sample gives anaccurate vision of the real inbreeding. These parameters and theapplication of the concept of average relatedness allow us to recommendto the breeders the choice of the best matings to control theinbreeding level while maintaining a low paternity error rate. (C)Inra/Elsevier, Paris.