Income and Risk for Dairymen Selecting Sires for Artificial Insemination

Open Access
Publisher Website
Google Scholar
Abstract
Expected income and risk for dairymen was computed for alternatives of sire selection. Mean transmitting abilities for dollars of young unproven and old progeny tested bulls were considered. Accuracy of progeny test (repeatability), total number of bulls and proportion of young bulls used in the herd were varied. A prediction function for semen price was estimated for progeny tested bulls from their predicted differences dollars and their repeatabilities. A constant semen price was assumed for young bulls. Expected income of a sire transmitted to a daughter and her offspring was estimated by an index including semen price and income over feed cost. Risk was defined as SD of income. With the same mean transmitting abilities for young and old bulls, expected income increased with increasing proportion of young bulls and decreased repeatability of old bulls because of higher semen price for old bulls and increasing semen price with increasing repeatability. When transmitting abilities of old bulls are larger than those of young bulls, expected income for old bulls still could be smaller because of higher semen costs. But it also could be larger if expected income is large enough to offset the difference in semen price. Risk increased with increasing utilization of young bulls, decreasing repeatability of old bulls, and decreasing total number of bulls used. The decision of what selection alternative to use depends on the dairyman''s individual weighting of expected income vs. risk.