YEARLY TRENDS IN THE PERFORMANCE OF BULLS ENTERED AT THE SASKATOON ROP BULL TEST STATION

Abstract

Trends were determined for the performance traits of beef bulls of five breeds tested at the Saskatoon ROP bull Test Station between 1965 and 1986. Means were calculated for each year for each breed with respect to start-of-test weight, end-of-test weight, average daily gain-on-test, and adjusted 200-day weight. A significant (P < 0.05) year-of-test effect was found for each of the four traits studied for Angus; for start-of-test, end-of-test and 200-d weight for Hereford and Shorthorn; for start-of-test and end-of-test weight for Simmental; and for only start-of-test weight for Charolais. These data suggest that bulls in all five breeds were significantly heavier each year when entering the test and that all except Charolais were heavier each year when completing the test but that only the Angus breed gained weight on test at a significantly faster rate each year. Key words: Record of performance, bull, beef