Estonian scientists can help beef and dairy farmers develop "super herds" with a new embryo screening process to assess animals' suitability before birth. This new method aims at improving the overall health of herds.
"Currently in Estonia, we have a situation where our dairy herds are producing a lot of milk, but in terms of health, the herd needs a lot of improvement. Embryo technologies can offer a very fast way to do this," said Monika Nõmm, a junior researcher at the Estonian University of Life Sciences.
In Estonia's large dairy farms, while a new generation of cows is being created through artificial insemination, some farmers are skeptical about using the new method, Nõmm said.
"The technology works by taking eggs from a female, fertilizing them in a test tube, and growing them in an incubator for seven days. After seven days, we have an embryo ready to transfer back to the recipient animal," she said.
In their recent study, Nõmm and her colleagues searched for hereditary markers and patterns that would make it possible to find the best embryos.
Nõmm said early-stage embryos look like raspberries: "In the beginning, there is a single fertilized egg cell, which then starts to divide into two, four, six, eight, 16, 32 and so on."
If two cells are removed at this stage, it does not interfere with the embryo's further development.
"By analyzing these two cells, we can tell the next day, for example, whether the embryo is male or female," Nõmm said. Additionally, researchers can find information related to the potential milk production capacity and health problems based on a tissue sample. "All this information is present in the little embryo from the start," the junior researcher said.
Nõmme said the new method has several advantages over the previous ones. For example, one cow with very good genes can produce more offspring per year in this way than with insemination.
"When producing embryos, we make the cow superovulate. Usually, one animal produces one egg per month. However, if we stimulate cows with hormones, it is possible for one animal to produce up to 10 eggs in one cycle," she said.
This allows the farmer to quickly improve the health of the whole herd and spend less money on animal treatments.
"It also improves the quality of the food we eat, because the healthier the animals and the less they are treated, the less risk there is of residues of different medicines ending up in our food supply," Nõmm added.
She said another benefit is that frozen embryos can be stored, essentially forever.
Additionally, it does not matter which breed of cattle the embryo is transferred to.
"It is possible to use inferior animals, which are in good health but do not produce as much milk, for example. This animal can gestate to the end of its pregnancy and give birth to an offspring that has no genetic link at all to its own genetics," the junior researcher said.
Nõmm said Estonian dairy farmers are still rather skeptical about the new method. However, beef cattle breeders already buy embryos with good genes from abroad.
She believes the new method should be more widely adopted and wants to offer farmers more information. She said they can seek advice from the university.
"That's what my job is now, to make farmers and livestock producers aware that this is a good methodology and a great way to improve their livestock," she said.
Nõmm's research was published in the journal Genes.
Editor: Helen Wright