Development of the coefficient of inbreeding and relationship in the finnish ayrshire breed

Abstract

On the basis of samples of cows taken from the herd hook (4-lines pedigrees carried back to 1894-97) and on pedigree information (7 generations) for AI bulls the level of inbreeding and relationship in the Finnish Ayrshire breed was studied. By year of birth, samples of 50 cows were taken for each of the years 1915, -25, 35, 45, 55 and — 60 as well as a sample of 100 cows for the year 1965. The 783 AI bulls analysed were born between 1939 and 1962. The coefficient of relationship rose from 2.0 ! 0.5 per cent in 1915 to 7.3 ! 0.6 per cent in 1965 and has, in the period 1945-65, remained at the same level. Over the whole period studied the coeflicient rose, on an average, 0.77 per cent /generation, i. e. O.là1 per cent /year. The coefficient of inbreeding (F!) rose from 1.2 _I0.4 per cent in 1915 to 3.2 1 0.4 per cent in 1965. Up to 1935 the observed coefficients were in agreement with those expected on the basis of the degree of relationship. In the following 20 years period the observed Fx values

DOI: 10.1186/1297-9686-3-1-101A

Cite this paper

@inproceedings{Lindstrm1971DevelopmentOT, title={Development of the coefficient of inbreeding and relationship in the finnish ayrshire breed}, author={U. B. Lindstr{\"{o}m and Kalle Maijala}, booktitle={Annales de g{\'e}n{\'e}tique et de s{\'e}lection animale}, year={1971} }