Selecting at negative 9 months – High Plains Journal

Posted: August 7, 2017 at 3:44 pm

In 2014, the University of Arkansas estimated one purebred calf born from embryo transfer must have a market premium of $1,500 to $2,000 greater than naturally conceived calves in order to pay for the costs to produce it.

In the roughly 40 years or so that ET has been conducted in cattle, it wasnt until recently that embryos could be sorted according to sex. And most of that has been done in the dairy cattle businessnot the beef cattle business. That means even a successful ET calf on the ground may not in fact meet the ranchers selection requirements for that premium price that would pay their costs of production. Or, the calf may not exhibit the physiological traits that would match what his or her genetic potential had been on paper.

Months of planning and thousands of dollars invested in harvesting and implanting an embryo may either wind up in a stellar replacement female to advance your herds geneticsor it might result in a bull destined for the steer pen.

But Matt Barten, of Embruon, Salina, Kansas, is working to change that one beef calf embryo at a time. His company uses bovine embryo biopsy and genomic data captured by the various purebred beef cattle associations to evaluate embryos for producers. With a few cells, Bartens company can tell a rancher not only the sex of the embryo, but also what genetic traits the calf will exhibit in the pasture or in the feedlot.

I say that its making those genetic decisions at negative nine months, Barten said. By the time you have an embryo calf on the ground, you could have up to $2,000 in that calf. So, if you can make the decision to implant that embryo based on what that calf is in the nitrogen tank, it saves you time and money.

With embryo transfer, by and large, the biggest dollar figure and resources that you have tied up are in the recipient herd, Barten explained. Using his embryo biopsy technology a rancher can make transplant decisions as to not only what gender those embryos are, but if they have a recessive genetic profile or traits that a rancher would like to bring into a herd, before a pregnancy occurs.

Maybe more important is that it can help cattlemen build the desired genetics in their herds with more precision than they have ever had in the past.

Early adopter

Charlie Cartwright owns Cannon Ridge Angus in Shelbyville, Tennessee. He and his wife have built their Angus herd using artificial insemination, in vitro fertilization and embryo transfer since he retired from the military in 2013.

We bought the first 10 pregnant cows in September of 2013, just by going to various sales across the nation and trying to build our genetics, Cartwright said. Cannon Ridge markets replacement females to purebred cattlemen, so its important that he be able to select female embryos to transfer. But some ranchers might be more interested in the other capabilities of the testing, such as telling if an embryo carries harmful genetic traits that theyd like to select against.

My focus right now is on getting more females, Cartwright said. But as we get down the road and as GE-EPDs and DNA testing is more prevalent, we might start to look more at the DNA of the embryos. If Matt can tell me that these are her numbers, I can choose if I want to put that embryo in. If the embryo shows more traits coming from the mother or the sire, maybe I decide not to put the embryo in.

When we got started it was because I wanted to do full genomic profiling, Barten said. We wanted to offer the GE-EPD at Embruon. So now, using information from the Angus breed association, we can know genomically what that calf will be at the embryo level. We can tell within a group of 10 or 100 which embryos will have more carcass potential or more maternal potential genomically.

And, with each breed association collecting more genomic data on its cattle, the Embruon process can be used for practically any purebred cattle embryos.

Cell amplification

The process is breed-specific, Barten said. Probably the most applicable in the dairy industry because they have so many genotyped animals already. The Angus breed, though, is one that has built up its number of genotyped animals, he added.

Embruons process is fairly simple. A rancher like Cartwright can use conventional flushing methods to get embryos from his cows. Then, he overnight ships the embryos to Barten at Embruon in a culture media to grow while theyre on the way. Barten said its like culturing bacteria on a petri dish. The embryos are biopsied the next day.

The biopsy just takes a few cells from the outer layer of the embryo cell, what would eventually develop into the placenta for the calf in utero, Barten explained. This is where the process gets really delicate. Unlike a DNA sample from a live animals hair or tissue that is composed of hundreds of thousands of cells, there are fewer cells in an embryo to test. Barten works with Neogens GeneSeek Operations in Lincoln, Nebraska, to amplify the number of cells to get enough DNA for evaluation using the genomic data from the breed association.

Embryo before biopsy. (Photo courtesy ofEmbruon.)

Embryo after biopsy. (Photo courtesy ofEmbruon.)

Embryo recovering from biopsy. (Photo courtesy ofEmbruon.)

Embryo before biopsy. (Photo courtesy ofEmbruon.)

Embryo after biopsy. (Photo courtesy ofEmbruon.)

Embryo recovering from biopsy. (Photo courtesy ofEmbruon.)

The most difficult part of this was trying to get the DNA to amplify, Barten said. Its like having to turn a bushel basket of corn into two semi-loads so that you can run it through the pipeline.

Except, in this case every copy of those embryonic cellsevery corn kernelhas to be identical following amplification, or youll introduce errors. Barten said if theres an error in the cell amplification, it can introduce bias into the testing.

These cells have to go through amplification somewhere on the scale of 2,100 times, Barten explained. If you introduce an error, then the genetic prediction starts to get really skewed. Think about a sniper taking a shot at a half of a mile. If youre just one-eighth of an inch off, when you shoot, by the time the bullet reaches the target its a foot off. It took Barten working with GeneSeek a year to get the process fine-tuned so that theres a high degree of accuracy.

We need two things at the end of the day, Barten said. We have to have a high degree of accuracy in predicting what the embryo will become, and we have to be able to transfer the embryo for pregnancy.

Following their biopsy, the embryos stay on their culture for a little while to recover. Barten will look at the embryos under the microscope and evaluate if they are recovered and able to be implanted.

Moving the cost curve

From here, a breeder has two choices. The embryos can be frozen and the breeder can wait on the data to decide to implant them, or they can go ahead and implant them and decide after he gets the data if the pregnancies are what he desired. It all depends on their market goals, their labor resources and other factors.

This process works well for ranchers who dont have an infinite pool of recipient cows at their disposal, and who really need to make every decision count before they tie up their resources, Barten said. Its about moving the cost curve back to the point before theres a calf, and resources are devoted to something that isnt desired.

By making their decisions at negative nine months, the rancher can do in a year or two what it would take some other operation three to four years to do, Barten explained. Thats because every year hes making his decisions on the embryonic level, knowing what hell get. Barten worked with a Kansas State University graduate student, Dustin Aherin, to crunch the numbers. Using computer modeling they found the expense to run double the number of recipient cows in a year can add up to $40,000 in costs in a year, and a rancher could still wind up with calves he would not be able to sell at or above market value.

Bovine embryo biopsy isnt new, Barten said. The technology is used in many other applications. Barten developed his concept for Embruon after he graduated from Fort Hays State University. Hes worked as a bovine ultrasound technician and as an embryo transfer technician. In 2014, he had some clients who were dealing with a recessive trait in their herd, and he thought if he could identify the embryos that were free of the disorder versus those who were carriers, that he could help them. Eventually that led to the creation of Embruon, Barten said.

The science of the technology is what appeals to Cartwright and one of the reasons why hes an early adopter. Hes looking to see this fall in the 10 recipient cows hes implanted with Embruon-evaluated embryos what their pregnancy rates were and what were the final costs of his operation invested in the procedure.

Every cow and every rancher is different, and there are a lot of ways to do embryonic production, Cartwright said. I look at each one as a tool in the box. He added that ranchers need to evaluate for themselves if technology like this will work for them.

Barten is optimistic about the future of his company. They have plans to expand laboratory space into Wichita, Kansas, and adding staff to ease the workload. But for him, the real point of pride is helping cattlemen like his dad improve their herds more efficiently than they were ever able to before.

And all before an embryo is ever implanted.

Jennifer M. Latzke can be reached at 620-227-1807 or jlatzke@hpj.com.

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Selecting at negative 9 months - High Plains Journal

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