Sexten: Lessons From the Dairy Industry
You will be hard pressed to find a current beef publication that doesn’t reference beef on dairy calves somewhere in the copy as the number of dairy cows bred to elite beef producing bulls continues to grow. The ability to produce a steady and sufficient supply of elite dairy replacement heifers has been enabled by two technologies widely adopted in the dairy industry: genomic testing and sexed semen. The widescale use of these technologies offers a window into the future of the beef production system.
A recent article1 in Frontiers from George Wiggans and Jose Carrillo at the Council on Dairy Cattle Breeding reviewed the impact of genomic testing in dairy cattle genetic improvement. This review and the associated changes in the dairy production model highlight the ability to change selection focus when we expand beyond simply using bulls as the source of genetic improvement.
Since 2011, the number of dairy cows evaluated using genetic testing has doubled every five years to exceed one million annually. Don’t miss that the use of genetic testing is doubling in COWS. Growth in the use among sires is flat, as less than 1% of sires used in dairy matings are not genetically tested. Since genetic testing for dairy sires is table stakes, this has enabled the reduction in the sire generation interval to the point where genetic improvement is occurring at the biological limit.
Knowing the individual genetic merit of the cow herd enables the strategic mating of tested cows to either produce dairy replacements or be mated to beef sires. With the advancement of sexed semen further specialization is enabled, as the by-product of targeted matings is virtually eliminated.
Beef producers are now competing with a dairy whose by-product is feeder calves. The characteristics of this by-product address three key challenges of the native beef supply chain: eliminating seasonality of supply, easily sourced in load lots and uniform management despite individual sorting early in life. While there is much attention to beef from dairy cows, the percentage of the beef supply chain originating from dairies hasn’t changed nearly as much as the genetic potential of the cattle themselves.
Imagine a production system where sire genetic improvement is occurring at the biological limit coupled with a cow herd that that turns over every four years. Despite dairy cows being productive for about half as long as a beef cow, genetic testing in dairy herds exceeds that of beef herds. The dairy model has moved their genetic focus from selecting replacements from a system to creating the replacements needed for their system.
The Net Merit score is an index used in the dairy industry to implement genetic selection of replacements. How would you weight the following areas if designing the net merit index: milk yield, milk components, health, longevity, reproduction, efficiency, and physical characteristics?
The article from the Council on Dairy Cattle breeding1 outlined the weighting of the current net merit index: milk components (48.3%), longevity (20.8%), efficiency (13.2%), reproduction (9.6%), health (4%), physical characteristics of feet and udder (3.8%) and finally milk yield (0.3%). Anyone else surprised the lowest category of emphasis is milk yield? Perhaps dairies have reached the limit on milk yield. A similar case could be made for weaning weight and milk production in the beef herd where we are limited more by the environment than genetic potential for productivity.
The emphasis on milk components suggests making progress enhancing the composition of milk is more important than total yield. From a beef production perspective carcass merit would be similar to component improvement. There are few beef selection indexes where the composition of carcass gain is more important than the gain itself. Cattle feeders recently proved with cheap feed and days on feed beef carcasses weights can be increased to record levels, perhaps it’s time to change focus to ribeye area and marbling.
The ability to select for longevity, efficiency, and reproduction is not limited to dairy cows. Beef producers have genomic tools available today to make genetic progress in all these areas, yet few operations have adopted genomic testing for any traits. In an industry where feed costs make up the greatest percentage of operating costs and reproduction is the most important production trait; we should not continue to ignore the tools available to make progress in these areas. Beef producers can select replacements designed for our production systems before ever turning out a bull.
Some suggest the dairy model doesn’t apply to beef systems due to the diverse environment. Every cow herd has environmental constraints that limit stocking rate comparable to the limited number of parlor spots in a dairy. If you are trying to optimize the production of beef per acre is a replacement selection model where keeping the biggest and oldest heifer calves with little knowledge of their genetic merit or variation within those females the best way to optimize the land resource?
