Think Backward

Market Endpoints Are Starting Points for Genetic Selection

Carcass traits are key for producers who want to retain ownership through the feedlot phase on calves. (DTN\Progressive Farmer photo by Victoria G. Myers)

It's a lot easier to pick the right bull if your thinking is a little backwards. Consider what advantages he brings to the point of sale for his calves, more than what he contributes from conception forward.

The first question, then, really isn't what genetic package a producer needs for the herd, it's what marketing program the bull needs to match. This mindset is especially key when working with selection indexes, a common tool today that has largely supplanted individual trait selection for commercial producers.

These selection indexes vary by breed, but they usually emphasize maternal traits, terminal traits or all-purpose traits. The key to knowing which type of index serves your financial goals best depends on your marketing program.

Darrh Bullock, University of Kentucky Extension beef specialists, says while knowledge of EPDs is far greater today than just a few years ago, he believes there's room to grow when it comes to the utilization of selection indexes.

"If it's the right index it can absolutely help the average commercial cattle producer," says Bullock. "Every index has underlying assumptions about how you plan to manage the herd, and how you plan to market the calves. If those assumptions are in line with what your actual herd goals are, selection indexes work extremely well. They essentially allow you to make your selection decisions based on economic, rather than strictly genetic, variables."


One of the challenges of using selection indexes for the typical, commercial herd these days, is that often producers want more than one thing out of their cows. They may sell calves at weaning, but also hold back replacement heifers. Selecting genetics that can produce great replacement females, is not the same as selecting genetics to produce a great calf crop with top-notch carcass traits.

"If you use a terminal index that puts a lot of value on carcass traits, that isn't going to benefit those replacements at all," notes Bullock. "And, conversely, if you focus on maternal traits, you aren't maximizing the economic value on the calves. So if I have a word of caution when it comes to a selection index, it's simply that they really do need to fit with your management program and your marketing plan."

To make it simple, Bullock says ultimately the growth EPD in a selection index should line up with the operation's primary marketing endpoint.


For producers who like to hold back replacements for their own herd, or target the bred-heifer sales market, the key with a selection index is to emphasize maternal and production traits.

"The first question I'm asking myself when I look at a bull is whether I plan to keep his daughters. If the answer is yes, I consider maternal traits. If it's no, I don't."

What do maternal indexes emphasize? Every breed is a little different, but economically relevant traits in a maternal setting include calving ease, calving ease maternal, weaning weight, milking ability, reproduction and maintenance or longevity. It's important to consider environment when looking at maternal traits, notes Bullock.

"Performance traits we put in our cattle have to match their environment and our management. If their genetic potential is higher than what is supported by the management or environment, that leads to inefficiencies.

"Bragging about weaning weights should not be anyone's goal. Efficiency should be the goal, and that means we may need to reduce the size of our cows and their milking ability. Profitable operations have efficient herds."


Terminal indexes emphasize calf growth from weaning through finishing, as well as carcass traits. These are a good choice for producers who retain ownership through the feedyard phase on calves, but don't develop their own herd replacements.

"Think about how you market," says Bullock. "If you background that tells me the trait for growth is one that closely aligns with your market endpoint. If you sell at weaning, look for weaning EPDs. If you are going to background up to a yearling, there are yearling weight EPDs, and that is the growth trait I would be most interested in. If you're going to put them in a feedyard, the carcass weight EPD is the key. So the growth EPD should align with my marketing endpoint."


Some producers, if they have a large enough operation, find advantages in dividing the cow herd. Genetics aimed at producing good replacements are utilized in one part of the herd; carcass traits in the other. To work this requires a larger overall herd, one that needs at least two bulls.

"A lot of our herds are one-bull units," notes Bullock. "When we get into larger numbers we do see more people dividing their cows into more than one herd, and this certainly creates more market options. It's a very efficient way to raise cattle, but it takes numbers."

"I wish we could see more production totally devoted to high quality replacement females today," he adds. "Then you could also have more terminal type operations, which would be the most efficient way to run the industry."


A few other traits are key to a well-rounded herd, notes Bullock. Docility, for example, helps both producers who hold back replacements, and those that have calves going to the feedlot.

"More docile animals do better in the feedlot," notes Bullock. "They tend to gain better, and handle stress better."

Calving ease direct scores are important, especially if the bull is being used for heifers.

The beauty of EPDs and indexes, says Bullock is they definitely benefit a cattle operation when used correctly. How fast a herd can change depends largely on culling and what Bullock calls he "generation interval".

"This is the time required to replace one generation with the next," he explains. "Generation interval is affected by both culling rate and selection intensity. If the herd size remains mostly constant, selection intensity on heifers also determines selection intensity of culling cows.

"There is a difference between the generation interval in seedstock and commercial herds," he notes. "Seedstock herds seek to shorten the generation interval. Commercial producers want to use added maternal performance of older cows, making generation interval less important."