feed conversion

[waihou]

We in NZ have access to Genestar testing in Australia. They have identified 4 pairs of genes each for Tenderness, Marbling and Feed Efficiency-so possible top scores are 8 for each.

The figures I have read are that the top scoring breeds for feed efficiency are Brahmans, followed by Santa Gertrudis. The top British breed is Shorthorn, which is way behind the Bos Indicus breeds.

My thoughts on feed efficiency is that it must surely be a useful tool for more than just knowing which animals will do well in feed lots. Not only a bulls ability to eat and keep condition, but on efficient cows which can convert feed to both their own body and milk production at the same time.

I did ask a question of one of the Aussie gurus as to what part a cow with a good milk EBV (EPD) is inflenced by her feed efficiency genes, or those passed on to her calf in converting milk to growth, but as yet have had no reply.

This question was prompted after we got one of our top cows gene tested. She is already in the top (world?) 5% on International Group Breedplan for milk EBV, her score is +16 to a Murray Grey Breed average of +3. When her Genestar results came back she is also 7 out of 8 stars for feed efficiency, and 8/8 for tenderness. I would be interested if any of you had thoughts on whether you think feed efficiency works for the growth of the calf thereby is also expressed in a cows Milk EBV.

NFI tests are done in the feed lot. So if the test results are good it would it would only tell you that the calf would do good on less milk and of course the more milk the better. It would only be a comparison of calves getting the same amount of milk. Therefore it would not be expressed in a cows milk EBV.
On another note, can you say what the Murry Gray cows marbleing score was? Personely I would be willing to sacrefice some of those tenderness and efficency stars to get some marbleing stars. I beleive a more balanced animal is more important as with EBV's.[/quote]


Have just found the link to the data results between the various breeds tested by Genestar in Australia. This is on a Murray Grey members club website, hope it works!
http://web.mac.com/marykat1/Clubhouse/correlations.html