Trends in dairy cattle breeding and genetics

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ST. PAUL, Minn. – 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, the U.S. gradually developed a specialized dairy industry that featured butter. Milk production became important so the cows needed to become higher producers.
Building genetics. 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.
Gray clouds. A few clouds appeared on the dairy genetic horizon starting about 1990. Conception rates of lactating cows decreased from 60 percent to 70 percent to current levels of about 35 percent to 40 percent.
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.
Room for crossbreeding? 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 1950s to the ’90s showed 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.
Scandinavian influence. 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.
What they’ve found. From work to date, the Minnesota scientists concluded:

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