title: Evaluation of genetic variation in the international Brown Swiss population.
abstract: The international Brown Swiss cattle population pedigree was studied to measure genetic variations and to identify the most influential animals. Twenty-two countries provided pedigree information on 71 497 Brown Swiss bulls used for artificial insemination (AI). The total number of animals with the pedigree is 181 094. The mean inbreeding coefficient for the pedigree population was 0.77%. There was, in most cases, an increase in the mean inbreeding coefficient, with the highest value at 2.89% during the last 5-year period (2000 to 2004). The mean average relatedness for the pedigree population was 1.1%. The effective population size in 2004 was 204. There was notable variation between average generation intervals for the four parental pathways. The longest average generation interval, at 8.73 years, was observed in the sire-son pathway. The average generation interval for the whole population was 6.53 years. Most genetically influential individuals were sires. The highest contributing founder was a sire with a 3.22% contribution, and the highest contributing founder dam made a contribution of 1.75%. The effective number of founders and the effective number of ancestors were 141 and 88, respectively. The study showed that genetic variation within the pedigree population has been decreasing over recent years. Increasing the number of AI bulls with a low individual coefficient of inbreeding could help to maintain a good level of genetic variation in the Brown Swiss population.
authors: Interbull Centre, Swedish University of Agricultural Sciences, SLU, SE-750 07 Uppsala, Sweden. woredezinabu@yahoo.com
authors: G M
authors: GM
authors: Worede
authors: F
authors: F
authors: Forabosco
authors: B
authors: B
authors: Zumbach
authors: V
authors: V
authors: Palucci
authors: H
authors: H
authors: Jorjani
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D007178:Inbreeding; D007315:Insemination, Artificial; D008297:Male; D010375:Pedigree; D011156:Population Density