Why the Cattle Industry Needs to Up Feed Efficiency
The cattle industry must start to select for feed efficiency, said Dan Shike from the University of Illinois at the Cattlemen's College Feed Efficiency forum during the 2012 NCBA Convention. Charlotte Johnston, TheCattleSite editor reports.With the number of challenges faced by the industry, including less acres available for crop production, an increasing world population, increased utilisation of food for fuel and increasing feed and other input costs, one of the logical solutions is to increase efficiency.
Feed costs have historically been 50-70 per cent of the cost of production in beef enterprises, but with corn prices exceeding $7 a bushel last year, feed costs were nearly 80 per cent of the cost in many feedlot operations, said Mr Shike.
A feed efficiency improvement of approximately 10 per cent across the entire feedlot sector would have reduced feed costs by $1.2 billion in 2011.
Even a one per cent improvement in feed efficiency has the same economic impact as three per cent improvement in average daily gain.
"The cattle industry seems to focus on gain and output, but really we need to focus on the input side," said Mr Shike.
Measuring feed efficiency
Gross feed efficiency: ration of live-weight gain to dry matter intake (DMI). In this case the higher the number the better, it generally ranges between 0.12 - 0.22.
Feed conversion ration (FCR): DMI to gain ration. This is a measure of gross feed efficiency. The lower the number the better, ranges between -4.5 to -7.5.
FCR is a gross efficiency measure and does not attempt to partition feed inputs into portions needed to support maintenance and growth requirements.
Mr Shike explained that FCR doesn't take into account what is needed for maintenance of an animal.
Selecting only for improved FCR will indirectly increase feed costs for the cattle herd, said Mr Shike.
Residual feed intake (FRI): This is the difference between actual intake and predicted intake, based on gain, body weight and composition. In this case negative numbers are good, as the animal will require less feed than predicted.
This measurement is independent of growth and mature size. It is linked to biologically relevant traits linked with feed efficiency, said Mr Shike, such as digestibility, heat production and protein turnover.
Animals with a negative RFI require less feed for maintenance than those with a higher RFI.
Residual Average Daily Gain (RADG): This is the difference between actual gain and predicted gain based on animals intake, body weight and composition.
A positive RADG is good, said Mr Shike, as it means the animal has gained more weight than predicted.
* "A feed efficiency improvement of approximately 10 per cent across the entire feedlot sector would have reduced feed costs by $1.2 billion in 2011" |
Why are we so far behind?
On a feed to gain basis, cattle are the least efficient compared to other livestock, said Mr Shike. A fish will gain a pound for every pound it eats, whilst a chicken converts half of what it eats into body weight.
For cattle it takes seven pounds of feed to produce one pound of beef.
Since 1957, there has been a 250 per cent improvement in efficiency in poultry production.
The beef industry hasn't made any significant improvements in feed to gain ratios in this time, said Mr Shike.
As the rate of improvements in feed efficiency has slowed down, the genetics of feed efficiency is a largely untapped source of improvement, said Mr Shike.
There are a couple of reasons, which Mr Shike mentioned as to why the cattle industry hasn't made any improvements in this area. This includes the fact that higher fibre diets are being fed in feedlots, unlike diets fed to other protein sources. With corn and grain prices rising, more and more by-products are being fed, which are not as efficient by nature as grain diets, said Mr Shike.
Rumen fermentation, bacteria produced via volatile fatty acids, and methane emissions all make cattle less efficient than other species.
All of the above means that cattle have a higher maintenance requirement, with 50 per cent of feed intake used solely for maintenance, said Mr Shike.
Another reason why cattle are less efficient, explained Mr Shike, is that cattle are not currently selected for feed efficiency. This is because it requires individual feeding and monitoring - which is expensive to install. There is also a concern that a lack of social interaction decreases feed intake.
Advances in technology are making it easier. Growsafe units with wireless radio signals and collars to weigh each mouthful of feed taken are one way to measure feed efficiency, as is ultrasound technology.
The generation interval also holds the industry back. Pig and poultry breeders see multiple generations a year, whilst it takes at least two years with cattle to see a genetic change.
Components of feed efficiency
As mentioned before a one per cent increase in feed efficiency, can lead to a three per cent increase in average daily gain. More efficient cattle may have improved digestion, metabolism of nutrients or may utilise absorbed nutrients more efficiently.
Feed intake is used for two things, maintenance and production.
What an animal uses for maintenance depends on its genetics and the environment. Metabolic rate and cellular efficiency will affect this.
Production is growth, and this is influenced by body composition and nutrition partitioning. Production could be fetal growth, milk production, body condition change etc.
Mr Shike said that there is a major need for improvement in beef cow efficiency. 50 per cent of all feed put into the cattle industry is used to maintain the cowherd.
Diet type
Can we select for improved feed efficiency in the feedlot without having negative effects on the cowherd, he asked. Or better yet is there a way to select for improved feed efficiency in feedlot that will improve cow efficiency?
Cowherds traditionally eat moderate to low energy feed that is forage based, whereas finishing cattle in the feedlot tend to eat high energy, grain-based diets.
Controlled feeding trials have shown huge differences in forage intake by cows, with some eating as much as double others in their herd. And the low-intake cows are not always the low-performers. “This has a lot of implications for stocking rates and carrying capacities of pastures,” said Mr Shike.
Other trials have been ongoing that look at forage versus grain intake, trying to identify genetic merits through looking at the sires. Mr Shike said that data collection will continue to identify the genetics that are superior for both, or suited to a certain system.
“We have to get serious about this in the beef industry,” he said. "Gene markers are a good example of new technology which could help make a difference, already sires have been identified that are good in feed efficiency for grain and forage."
February 2012