The November 2000 release of the Estimated Relative Conception Rate measure is now available for AI bulls. The data, computed by Dairy Records Management System, provides fertility data on sires used in herds across the country.
The ERCR looks at the conception rate of bulls on first service in comparison to other bulls used within individual herds. Each bull is given a percentage ranking, ranging from -9 percent to 5 percent. In other words, a bull with a 5 percent ranking was able to settle a cow on first service 5 percent more frequently than other bulls. Ninety-two percent of the bulls are within -3 percent to +3 percent — considered the average range for fertility.
As with most genetic data, a reliability score accompanies the ERCR data. The higher the reliability — in this case, ranging from 49 percent to 99 percent — the more accurate the fertility analysis. Bulls need a minimum of 300 services to be considered.
To review the November 2000 release of ERCR data, visit the DRMS Web site at: http://www.drms.org/sire.htm