Understanding Beef Cattle Feed Efficiency and RFI (Residual Feed Intake)
Historically, the weight of an animal has been the most important component in determining value, which follows closely with production being the most heavily promoted and taught value in agriculture.  However, when you consider that more than 75% of the cost of growing cattle is related to feed inputs, and that 70-75% of the feed consumed by cattle is solely for maintenance requirements, then the importance of improving the efficiency of feed intake becomes very real.  With today’s feed prices, improving a herd’s efficiency of feed utilization is obvious.

What is RFI?
Residual feed intake (lbs/day).  The amount of feed intake an animal consumes daily, above or below its maintenance requirements as well as its performance (growth) requirements.  A negative RFI is a more efficient bull.  For example, -2.0 means the bull ate 2 lbs less feed per day than he needed to meet his body maintenance requirements and production needs (ADG).  With today’s feed costs, that is a savings of 40 cents/day or $72.00 per feeding period.  The difference between a -2.0 and a +2.0 bull is $144.00 in the feedlot.   If you are keeping replacement females, by selecting for negative RFI, research has shown you have the potential to save close to $60.00 per year on cow maintenance costs.

What does the research say?
Efficiency is highly related to growth and growth is the traditional method of measuring efficiency.  The problem is that using growth as a measure of efficiency also increases the size of the animal, which will increase maintenance requirements (70-75%) of feed consumed goes toward maintenance requirements), which will increase appetite, which will increase the need for available feeds/grasses.

1.  Using RFI will lead to improvements in feed efficiency without compounding the need for additional feeds or increasing mature size in your cow herd.

2. RFI allows you to produce at a level that optimizes on one’s management and environment instead of stressing it.

3. RFI is a highly heritable trait, meaning that through genetic identification and then selection, one can make rapid improvements.

4. RFI research has shown that improvement in efficiency can be made as much as 25%.

5. Selecting for efficiency will allow the cattle industry to become more competitive in production with swine and chicken.

6. Research has shown there is a 0.90 correlation (very high) between bulls measured for RFI post weaning and how their daughters will perform for efficiency in the cowherd.

Research Links: GrowSafe