Bull test WDA, FE, RTO, RFI ?

[Richnm]

Can someone please explain these to me. I understand ratios , and ADG. I don't understand WDA, FE, RTO,RFI? I purchased a bull out of a bull test and am trying to understand his test results.

 

[76 Bar]

I don't understand WDA, FE, RTO,RFI? I purchased a bull out of a bull test and am trying to understand his test results.

WDA= Weight/Day of age (generally favors younger growthy calves. FE=feed efficiency (input relative to gain. RTO=?. RFI=Residual Feed Efficiency. Reputable Test programs will gladly assist you. Good place to learn/understand performance parameters is your local or the national BIF.

 

[simme]

Info below on RFI is from a university bull test that uses an individual feeding bunk with load cells so that feed consumption per animal is monitored based on an RFID tag in the bulls ear. Generally the bull test sale catalog/book will explain all the terms and numbers.

 

[FungusProudKY31]

Studies at CSU decades ago were based on cattle in feedlot conditions. FE cattle on concentrated feed had less middle girth. So the bull test results might be good for terminal cattle on some of these traits but would be different on pasture cattle with no supplements. And I tend to believe that some bulls will not have the highest RFI because they are out doing "bull stuff" rather than just bellying up to the feed trough. For me, a bull developed from grazing tells me more than one that has been in a confined test.

 

[Lee VanRoss]

Fungus> You are at risk for thinking and a verbal skewering by the 4 color breedbook poorducers!

 

[simme]

Bull tests with high ADG sometimes result in poor feet, less longevity and problems down the road. Forage based development has better long term results. But many buyers can't resist a fat bull.