By Brad Buck
Farmers and University of Florida researchers use genetics and other techniques to ensure consumers can pick from the best assortment of delicious, nutritious dairy products at the grocery store.
Now that we’re in National Dairy Month, it’s a good time to appreciate the science-based innovations behind milk, cheese and other favorite dairy products.
UF Institute of Food and Agricultural Sciences dairy research includes testing a young calf to predict the chances it will grow into a cow that farmers want, said Albert DeVries, a UF/IFAS associate professor of animal sciences.
To do genomic testing, UF/IFAS scientists take a DNA sample from the calf, send it to a laboratory, which scores the calf for traits dairy farmers want: milk production, how quickly she will get pregnant, size and more, DeVries said.
“A major focus of many dairy faculty members is how to use DNA data in research and Extension,” DeVries said. “We have recently tested all dairy cattle at the UF/IFAS Dairy Unit with a genomic test. This means that at a young age, we get good genetic merit predictions. We are trying to see how well these tests predict the performance of the cattle. We also use the DNA results to discover genes that are associated with heat resistance, reproduction and more.”
“For us at UF/IFAS, the question is: What can a farmer do with these predictions so early in life?” DeVries said. For example, a farmer might decide to sell a calf that scores poorly for many traits farmers want. So, the process saves money.
Cattle go through genomic testing in developed countries worldwide, DeVries said.
On the Extension side, UF/IFAS dairy faculty try to teach farmers the value of genomic testing.
“It is only worth the cost if it changes decision making,” DeVries said. “Several leading dairy farmers in Florida now are looking to incorporate genomic testing in their herd management. This means they decide to sell some cattle, based on genomic test results.”
Farmers may also breed their cattle differently. For instance, they might use so-called “sexed semen,” which is sorted between males and females in a laboratory, DeVries said. They inseminate the cattle with the “sexed semen,” which increases the odds of producing a female calf.
On the other hand, sexed semen costs more, and the chance that the breeding results in a pregnancy is a bit lower, DeVries said. But if you use sexed semen to inseminate females with good traits, the odds that this valuable mother will deliver a genetically valuable female calf is much greater.
“So, using sexed semen together with genomic testing are two technologies that allow dairy farmers to have cattle that produce a lot of milk, stay healthy, get pregnant on time and improve other desirable traits,” DeVries said. “The cows get better and hopefully the farmer makes some money.”