Dennis Johnson, Dairy Production Systems, WCROC, Morris

June 03, 2006

There have been many changes in dairy cattle breeding over the years. Our ancestors needed multipurpose cattle when they immigrated. The cows were valued for draft, meat, milk, manure and hides, all of which were needed on the frontier. Starting about 100 years ago, Minnesota gradually developed a specialized dairy industry that featured butter. Milk production became important so the cows needed to become higher producers. The prevailing breeding system was grading up-buying purebred Holstein bulls from respected breeders. After several generations, the best grade Holstein herd was not very different from the purebred herd.

The next advance was the introduction of artificial insemination (AI) in the 1940s. AI combined with herd production testing (DHIA) allowed bulls to be compared by progeny test across many herds. Then came the digital computer, which allowed the use of sophisticated statistical models combined with sampling many young sires produced to the specification of bull studs. Production per cow sky-rocketed. Optimists were unwilling to predict a limit to production and recommended that selection be based on production alone-if other traits were important to production, they would improve as a correlated response.

A few clouds appeared on the dairy genetic horizon starting about 1990. Conception rates of lactating cows decreased from 60-70% to current levels of about 35-40%. There is little evidence to suggest conception will improve anytime soon. Cull rates and animal losses during first lactation have also increased. Culling is now based on fertility, foot and leg problems, and poor condition, which decreases opportunity to cull on merit or to add to farm profit by selling surplus springing heifers. Toni Oltenacu, Cornell University, presents strong arguments that the cow has not been able to adapt her physical system to the demands of very high production.

Many years of research with many animal species has clearly documented that vitality and fertility characteristics improve with crossbreeding. Crossbreeding of pigs, sheep and beef cattle is a standard practice. Until recently, little consideration has been given to crossbreeding dairy cattle. Although research from the 50s to the 90s showed that crossbred dairy cattle were vigorous and fertile animals. Now, many research organizations are evaluating crossbreeding.

Brad Heins, Les Hansen and Tony Seykora from the University of Minnesota have been at the forefront of crossbreeding research. They are monitoring the results of a crossbreeding program of seven large California dairy farms. The farms started from a high producing Holstein base that was crossed with Scandinavian Red, Normande or Montbeliarde bulls. Scandinavian Red cattle descend from native cattle with infusions of Ayrshire and other breeds. They have been selected for health traits and fertility as well as production. Normande are French cattle that are noted for their milk composition and ability to maintain body condition. Montbeliarde are a dairy strain of Simmental from France. Heins can be contacted for a report at hein0106@umn.edu.

From work to date, the U of M scientists have concluded:

• Inbreeding is increasing at about 0.1% per year in the Holstein breed, which is causing increased inbreeding depression, especially for mortality, fertility, health and survival.
• Crossbreeding results in heterosis, which is the opposite of inbreeding depression.
• Heterosis is a bonus that comes on top of the average genetic level of the two parent breeds and should be about 5% for production and at least 10% for mortality, fertility, health and survival.
• Mating Holsteins to Swedish Red, Norwegian Red, Montbeliarde, and Normande AI sires resulted in fewer stillborn calves, as well as cows with less calving difficulty, enhanced fertility and improved survival compared to pure Holsteins.
• Production of Montbeliarde-Holstein crossbreds and Scandinavian Red-Holstein crossbreds was very similar to production of pure Holsteins (about 5% lower).
• Crossbreeding systems with dairy cattle should use three breeds to capitalize adequately on the benefits of heterosis.

I have a few concerns about starting a crossbreeding program with a natural service bull. A crossbreeding program will be most effective if started by analyzing the traits you want to improve, then selecting bulls and breeds with a proven record of performance for those traits. Make a strong effort to utilize AI because proven bulls are available, fertility of semen is documented, disease is less likely to be introduced, and there is always the danger that a bull will go mad and kill you. Strengths and weaknesses of breeds are documented so it is possible to set up a good three-breed rotation based on your own goals. But don't assume that you or the geneticists will come up with a single perfect breed combination that fits all needs. It will take years to sort out optimum breed combinations. To date, there hasn't been adequate economic evaluation of the relative contributions of production, fertility, vitality as expressed by care costs, replacement or milk sales, and value of meat. Bottom line economics should outweigh production levels for most farm situations.

A Montbeliarde-Jersey-Holstein crossbred from U of M crossbreeding research at St. Paul and Morris.

A Swedish Red-Normande-Holstein crossbred from a California herd.