Performance Trends for BIO Evaluated Bulls

July 24, 2002

We would like to share with you the results of a study of the BIO Bull Evaluation Program performance trends. Average performance of bulls completing BIO’s evaluation program from 1995 to 2002 are displayed in charts for each measurement. Over 10,000 bulls have been evaluated in the eight years included in the summary.

The traits included in the summary are:

	Birth Weight
	Adjusted Weaning Weight (200-day weight)
	End of Test Weight (380-day weight)
	Average Daily Gain on Test (112-days)
	Hip Height (end of test)
	Frame Score
	Scrotal Circumference (end of test)
	Ultrasound Backfat (end of test)
	Ultrasound Ribeye Area (end of test)
	Ultrasound Intramuscular Fat (Marbling) (end of test)

Charts for each trait are available in a summary of all breeds, as well as by individual breed.

Some of the trends that we have identified across all breeds are:

Trait	Yearly Trend	Predicted Change in 10 years
Birth Weight	ê 0.2 lb per year	ê 2.0 lb
Adjusted Weaning Weight	é 4 lb per year	é 40 lb
End of Test Weight	é 4 lb per year	é 40 lb
Average Daily Gain	é 0.03 lb/day/year	é0.33 lb/day/year
Frame Score and Hip Height	Remaining steady	None
Scrotal Circumference	é 0.1 cm per year	é 1.0 cm
Backfat Thickness	é0.25 mm per year	é 2.5 mm
Ribeye Area	é 0.1 square inches per year	é1.0 square inch
Intramuscular Fat	Remaining steady	None

These trends show that the average population of tested bulls in Ontario is moving in the right direction: Birth weights are declining while growth and muscle is increasing. This is due to well designed breeding programs using the technological tools available.

These numbers are based on the entire population of evaluated bulls, including all breeds and composites. You will notice that the trends are quite different for several of the breeds. Click on the breed button below to see the performance trends for each trait.

To view the on-line Benchmark Tables, make sure you have the Adobe Acrobat reader installed first. Then click on the links to the tables (i.e.: All Breeds.pdf) and your Acrobat reader. should automatically display the tables to the screen.

Click on the Adobe Acrobat icon (on right) to download a copy of the latest version of the reader (6.5Mb approx. 25mins to download). You may also visit Adobe's web site at www.Adobe.com for more information.