Livestock Studies 1995, Vol 35, Num, 3-4     (Pages: 044-049)

EFFECT OF INBREEDING ON AGE AT FIRST CALVING OF BROWN SWIS RAISED AT REGIONAL AGRICULTURAL SCHOOL IN VAN

Ali KAYGISIZ 1 ,Yusuf VANLI 1

1 Department of Animal Breeding and Genetics, Faculty of Agriculture, University of Kahramanmaraş Sütçü imam. KAHRAMANMARAŞ -TÜRKİYE - The aim of this study was to determine the whether the Brown Swiss cattle raised at Regional Agricultural School in Van were inbred and to calculate the effect of inbreeding on age first calving.

Mean coefficients of inbreeding were found to be 6.88 ± 0.96 %, ranging between 0 % and 34.38 %.

The regression estimate for age at first calving was 1.72 ± 1.61 days, which indicated that the age at first calving increascd by 1.72 days for each one percent increase in inbreeding. The regression analysis showed a non-significant (P>0.05) effect of inbreeding on age at first calving. Keywords : Inbreeding, Age at First Calving, Brown Swiss Cattle