On-farm embryo transplants build better genetics
With the high prices offered in the cattle market, the commercial cattle buyers may be willing to spend more dollars by purchasing a purebred bull to improve the genetics of the herd. As science and technology explode in many directions, opportunities to enhance cattle breeds are expanded through the use of embryo transplants.
In humans, the procedure would include the use of paid surrogates. In the livestock world, those receiving the embryos from the donor cow are considered “recipient cows” according to Dr. Boyd Bien of Lake City, where his business ET Transplants is located.
Bien said that the advantage in performing embryo transplants is that “producers can have multiple offspring from the superior female, rather than just one calf per cow each year. The procedure can be expensive but is a way to increase the number of offspring from superior parents.”
Brad Hart of Angus Farms of Frederick is one of the seedstock cattle producers looking to increase the number of calves a prime cow can have. “While the procedures are expensive, it’s more than doubled the number of good males we have to sell,” Brad said. “We have more calves, and we still have good females with a good cow herd. You can’t pick out a calf (out of a herd) that has been the results of an embryo transplant but you can tell by the improved genetics by the time it gets to the sale ring.”
Brad said that his dad, Charlie Hart, was one of the first in the area to use artificial insemination to enhance the Hart herd. Keeping up with changes in the industry draws buyers to their sales to check out the qualities that the animals exhibit.
Brad’s wife, Shawn, explained that using embryo transplants is similar to human couples that can’t have children. In humans the procedure would be “in vitro fertilization.” The eggs are taken from the cow that has very good genetics and placed in a cow that has good characteristics for carrying calves. It’s similar to having a surrogate mother.
Brad’s daughter, Kelli Hart, his son, Alex, and Alex’s wife, Tanae Hart, are all committed to providing the genetics their customers want in their cattle.
Bien acquired knowledge and skill in this field of veterinary medicine in Texas and now has moved to the area where he grew up to work in this expanding field. He worked in Texas from 1982 to 2011, but always planned to come back to South Dakota. He returned three years ago. He now works at facilities near Lake City that are managed by Marty Jenson.
“I developed a love for the cattle business and the people involved. After gradating from Kansas State University with a veterinary degree in 1976, I worked in a large/small animal practice before moving to Texas where I began to work exclusively doing embryo transfer in cattle. I have owned and operated BovaGen since 1983, offering full-service, on-farm and in-clinic embryo transfer series.” During this time, he personally performed more than 25,000 collections and more than 100,000 transfers.
Information from the Oklahoma Extension site says that the first commercial embryo transfers in the United States were done in the early 1970s. Initially, embryos were recovered from valuable donors and transferred to recipient animals using surgical procedures. It was not until non-surgical methods were developed in the late 1970s that embryo transfer grew in popularity. The non-surgical technique is less expensive and lends itself to on-farm transfers.
Producers choose their most valuable animals based on the genetics they’d like to have reproduced. Because of the costs involved, purebred breeders are most likely to use embryo transplants. Animals can either be taken to the Lake City location or Bien can travel to the farms or ranches. When going to a farm, he can pack his needed tools in his truck and set up in a room onsite.
In South Dakota, most of the purebred breeders’ calves are born in January, February and March. That makes April, May and June the prime time for the transplants.
The process takes time and patience. Cows are prepared with a series of injections. Heat is induced in the cow and then she is artificially inseminated. After 7 days, the embryos are flushed out of the animal. Bien checks under a microscope for the viable ones and then puts those in a straw for transfer to the recipient animal. Some of the embryos can be frozen for later use or can be sold.
Once the implant is placed, there is about a 60% success rate. Bien says the most embryos he’s taken from a cows has been 76 at one time. This process can be repeated every 40 days or so to have multiple groups of calves. Recipient cows are chosen for good maternal instincts.
In the United States, more than 500,000 cattle embryos are transferred each year. Unlike cloning which produces a replica of the same animal, an animal resulting from embryo transfer is a combination of the male and female traits, according to information from Oklahoma Cooperative Extension.
Information from the Oklahoma Extension indicates that there are an estimated 150,000 potential “eggs” or ova in the female cows and countless billions of sperm produced by each bull. By natural breeding, only a fraction of the reproductive potential of an outstanding individual could be realized, the report said. The average herd bull will sire 15 to 50 calves per year, and the average cow will have one calf per year
The Hart family has worked with embryo transplants from Dr. Bien for the last three years and has been pleased with the results.
The Harts take the cows to the facility at Lake City for the transplant process. “With everything going on in the spring, we don’t have the time to do the work ourselves,” Hart said. “We have 3 cows there now and will have 2 more going this week. We have about 150 (embryos) in the tank which should be enough.”
“Embryo transplants allow us to improve the genetic line so much quicker,” Hart said. “Once the embryos are transplanted, the cows are become the responsibility of Dwight Johnson at Dallas, S.D., owner of one of our satellite herds. We do a parentage test on the calves to confirm their ET status.”
Each year, the success rate is different. For the Harts’ last year it was 72 percent; this year it’s about 52 percent.
When the Hart cows are flushed, there have been from 2 to 22 viable embryos. The animals can be flushed again two months later.
Hart explained that it’s best to wait until after the cow has her first calf before she undergoes the transplant procedure.
“After the initial year, the cows have a year off to have a natural calf,” he said. “Then she can be flushed again. If the process is used too often, the animal may quit producing eggs.”
Oklahoma Extension estimates that each “ET” calf must have a market value of $1,500 to $2,000 greater than other naturally conceived and reared calves in the herd for it to be profitable.
In addition to the embryo transplants, the Harts artificially inseminate about 350 of their cows. Bull calves are sold, with the 2014 average bringing just over $6,000. The heifers are kept in the herd. Some animals have gone to Texas, Illinois, California and North Carolina. In 2014, the Harts sold a bunch of heifers to Russia.
When the Harts look at their cattle, they are looking for the right phenotypes, including calving ease, high weaning and yearling weights, and functionality in the real world, just to name a few things.
Genotype is the instructions the body uses to grow, and it’s the foundation for genetics, including specific traits such as hair color. Phenotype is how the genotype makes itself known, the value of the trait. Phenotype is the individual’s observable characteristics, determined by environmental influences and genetic makeup. In cattle, phenotype can take on qualitative or quantitative properties.
On the horizon, there are all sorts of new ways to improve genetics. As science evolves, Hart thinks producers will be doing profile testing to improve the quality of herds. This involves sending in a blood sample. In return, the readout provides a look at the potential of the offspring. Already, cattle are being cloned and semen is being sexed.
Speaking on the future of the cattle business, Hart said, “I believe there is going to be some regrowth and they will be turning to breeding stock to improve the quality of their herd. It’s going to be tough because it takes a lot of hard work and many young people don’t want to commit to what’s needed in the livestock industry.”