The built-in feed efficiency of Aubracs

Producers in every sector of the cattle industry are facing rising costs of production, but none that impact the bottom line or their operations more than the cost of feed.
During the last year, Aubrac breeders in both the United States and Europe have used a DNA test for feed efficiency that was recently developed by Bovigen, a leading genetic company.

A recent DNA sampling of 67 fullblood Aubracs in the U.S. and France supports the assertion that Aubracs are a feed-efficient breed, particularly when compared to Angus and Herefords.

The chart above includes the results of the tests, and shows that Aubracs "bend the curve" toward greater efficiency with a higher percentage of cattle with 7 and 8 stars than Angus or Hereford.

Bovigen's GeneSTAR Feed Efficiency test consists of four markers that together identify as much as a 15% difference in daily feed consumption with no affect on other traits like average daily gain, carcass weight, quality grade or yield grade.

Bovigen believes producers can use the GeneSTAR Feed Efficiency test to identify up to a $50 difference in feed cost between animals when ration costs are at $165/ton.

Net Feed Intake
The DNA test is based on discovery and validation work on thousands of cattle utilizing the trait of Net Feed Intake (NFI), sometimes also called residual feed intake or net feed efficiency.

NFI is the difference between an animal's actual feed intake and the amount of feed an animal is expected to eat based on its size, composition and growth rate.

Calves that eat less than expected will have a negative NFI, and are more feed efficient than calves with a positive NFI.

Whether yours is a cow-calf operation where feed costs typically make up more than 65% of the total variable costs or a feedyard where a 20% improvement in feed conversion can affect profitability by more than $60/hd; feed efficiency is a trait that directly affects the bottom line.

Expectations and applications

Selecting for animals with more stars for feed efficiency can dramatically reduce the lbs. of feed consumed per day, says Bovigen.

Studies suggest there is a difference of as much as 4.15 lbs difference in feed consumed per day between 2 star and 8 star animals.

With a ration cost of $175/ton and cattle on feed for as long as 150 days, the difference between a 2 star and an 8 star animal is $54.47.

As with all results from Bovigen, the GeneSTAR Feed Efficiency results are expressed as both stars and a Genetic Progeny Difference (GPD).

The stars represent the results for each individual marker and are essential in making mating decisions.

The GPD represents the true genetic merit of the combination of markers and is created through analysis of previously tested populations of animals.

In the case of GeneSTAR Feed Efficiency, the GPD is expressed as fewer lbs of feed eaten per day.

As such, a greater negative number means a more efficient animal. In other words, an animal with star results of 2,2,0,2 and a GPD� of -3.48 will eat 3 lbs less feed each day than an animal with star results of 0,0,2,0 and a GPD of -0.48 - but gain the same amount of weight.
The sampling of all 67 head of Aubracs revealed the average GPD for these Aubrac cattle was -3.09.