Stereotypies in ranch mink: the effect of genes, litter size and neighbours.

This study was conducted on two generations of ranch mink to test the hypothesis that the behaviour of stereotypy (SY) in ranch mink is subject to heredity. Two groups of 14 females were selected as low stereotyping and high stereotyping individuals as extremes from 61 females. They were observed in two periods, one before mating and one after mating. The selection was based upon four SY frequencies of which two excluded the parameter Pendling. The kits of the two groups of females were also observed and the difference in level of SY between the two groups of mothers was upheld in the next generation. Combined with the finding of a positive, though not significant, correlation between the SY frequency of mothers and the mean frequency of litters this indicated a genetic effect upon the level of SY. A positive correlation between the litter size and the mean SY level of the litters was found. Though not significant it was considered important. A neighbour effect on the SY level in farm mink could not be found. All these results were obtained regardless of whether or not Pendling was incorporated into the SY frequency indicating that Pendling is induced by the same factors as other SYs.