Realised response to short-term selection of the common pheasant ( Phasianus colchicus) selected for seven-week body weight
The aim of this study was to evaluate the effect of the directed positive selection of the common pheasant for a higher seven-week body weight (BW) relative to their gender on the realised response to the selection and adult (40-week) BW after four generations of selection. The founder population was not selected before for any traits. For the selection in generation one of the experiment, a total of 2 080 pheasant chicks were used to establish a selection line (SL). In the same year, a total of 400 pheasant chicks were randomly selected as a control line (CL). Within the SL, chicks from individual hatches were selected by sex, always based on live BW at the age of 49 days. The targeted selection was carried out for four generations. In all generations it was found a higher seven-week BW in males compared to females ( P<0.01). In generations two, three and four, the BW of the SL in both sexes was always higher in comparison with the CL ( P<0.01). The genetic improvement of the seven-week BW was 15.0, 6.4 and 10.1 g in generation two, three and four, respectively. In the last generation, the increase in the seven-week BW of the SL compared to the CL was higher in females than in males (8.00 and 6.66 %, respectively). The realised heritability for the seven-week BW was 0.19. The selection at the age of seven weeks also caused an absolute increase in BW of adult pheasants at the age of 40-weeks.