A comparison of fattening performance between Holstein and Brown Swiss bulls and effects of inital weight on the fattening performance

The first experiment was carried out whith three groups of Holstein bulls, each had 10 bulls. Avarage initial weights of ist, 2nd and 3th groups were 266.0, 323.0 and 370.0 kg, respectively. It was found that only leed efficiency differences were significant, between ist and 2nd, and ist and 3th groups. Groups which had more initial weight consumed more dry matter per unit weight gain.

In the second experiment, fattening performances of Holstein and Brown Swiss bulls were compared. Brown Swiss group had more daily weight gain, feed conversion ability and higher carcass dressing percentage. It was found that only carcass dressing percentage differenre was of statistical significiant.

The third experiment was done to determine the alteration in performance of beef cattle which had different initial weights. during fattening period. In this trial, initial weights of groups were 206.5, 302.8 and 360.2 kg respectively. As the fattening period had progressed, feed efficiency of all groups reduced, but the most rapid decrease was observed at 303.8 kg initial weight.

As a result, it was conctuded that there is a negative correlation between initial weight and feed effciency, and to choose young and lower weight beef cattle may be more adventageous. Keywords :