Browsing by Author "Venho, Liisa"

The Finnhorse is the only native horse breed in Finland. Finnhorse has faced several genetic bottlenecks that have reduced the breed’s genetic diversity. The aim of this study was to analyse breed’s genetic diversity using pedigree data, focusing on the level of genetic variation and relatedness of the current population (individuals born between 2000 and 2021). In addition to the changes in the inbreeding rate, relatedness, effective population size and generation interval, the study investigated the individuals that have had the greatest genetic impact on the current population, as well as the relationship coefficients of currently used breeding stallions to the current population. Data, including 88 782 animals, was received from Suomen Hippos ry. The average inbreeding coefficient of the horses born between 2000 and 2021 was 4,5 %. The average inbreeding coefficients have increased during the last decades, but the annual growth has been moderate. The mean generation interval was 12,5 years. The growth of the inbreeding coefficient over the past 13 years was 0,97 %. The average relationship of the latest age group to each other was 10,5 %. Relationship between stallions and mares has been increasing throughout the 21st century. After 2013, the average coefficient of relationship between sexes has remained above 11 %. In this study, the effective population size was 93,5 for those born between 2000 and 2021. The effective population size has decreased from 108,6 individuals of the age group born in 2000 to 94,6 individuals born in 2021. However, the effective population size has remained above 50 individuals, which is considered the limit for the occurrence of problems caused by inbreeding at the population level. Current Finnhorse population can be traced back to five founder stallions: Murto, Eri-Aaroni, Suikku, Vokker and Vieteri. Out of those, Murto has the most remarkable contribution on the population born between 2000 and 2021: around 14,2 %. The five founder stallions are all connected by their lineage. The most used breeding stallions of the 21st century were all from trotter breeding direction and their relationship to the mares of the current population ranged from 10,1 to 18,4 %. The lowest relatedness of all breeding stallions to the mares of the current population was 4,0 %. Eight stallions had less than 6,0 % relatedness. None of them were from trotter breeding direction. The genetic diversity of the Finnhorse has remained at a reasonable level, but it is worth noting that the close relationship of breeding stallions in the trotting direction will probably increase rate of relationship in the future. A wider use of genetically divers stallions and a more even number of mares per stallion could slow down the rate of relationship of the breed and increase the effective population size.