1999 年 20 巻 1 号 p. 31-39
To implement a given proportion of full-sib mating exactly, the selection of progeny should be based on couples rather than individuals. The variance, S2k, of family size (k) under this type of selection is formulated as S2k=2+(2βN-4)/(N-2), where β is the proportion of full-sib mating and N is the number of parents (half in each sex). Using this expression, equations for inbreeding coefficient and effective population size are derived. The equations were compared with the published ones, in which the Poisson distribution of family size (S2k=2) is assumed. Stochastic simulations were run to check the obtained equations. The predicted values from the equations were in close agreement with those observed in the simulations.