Estimating genetic variability in temperamental traits in German Angus andSimmental cattle

Behavioural traits related to temperament were studied and the genetic vari ability estimated in German Angus (Aberdeen Angus x German dual purpose bre eds) and Simmental cattle. Temperament was defined as the behavioural respo nse of the animal to handling. Five progeny groups of both breeds (Simmenta l cattle, n = 206; German Angus cattle, n = 249) were tested in 2 consecuti ve years, 2 and 3 weeks after weaning. The animals were tested individually with a combination of a non-restrained and a restrained test. Each animal was separated from a group of 10 (separation yard, 100 m(2)) into a smaller area then confined in a corner of the restraint yard (25 m(2)). Behaviour was recorded and temperament scores were given by three different observers . The parameters of separation time, time spent running, number of escapes, aggression, vocalisation and time spent in the corner directed by the hand ier were recorded. Analysis of variance was per-formed with a model includi ng breed, year, handler and sex as fixed effects. The model for estimating heritability included the sire as a random effect and sex, year and handler as fixed effects. In both models a regression on the age of the calf was i ncluded. The estimated heritability (+/-S.E.) for the different characteris tics of temperament were between 0.0 and 0.61 (+/-0.17) for German Angus an d, 0.0 and 0.59 (+/-0.41) for Simmental cattle with highest values for temp erament scores. These were negatively correlated with daily weight gain. Si mmental cattle were more difficult to handle than German Angus when conside ring the different parameters. The estimated heritability of some behaviour al traits open a way of selection for temperament in German Angus and Simme ntal cattle assuming the high standard errors of the estimated values were caused primarily by the limited number of animals. (C) 2001 Elsevier Scienc e B.V. All rights reserved.