Criteria for selecting bulls to purchase
January 14, 2013
Now that winter is fully upon us, it's the season for bull sales. The ads, fliers, and sale catalogs are filling our mailboxes. Commercial producers will have the opportunity to choose from a large number of bulls with a wide variety of characteristics from dozens of seedstock producers. How will a commercial producer choose wisely among all these options? Making a wise choice is important. If the bull is a terminal sire, he will have a tremendous influence on the sale value of his progeny. Beyond that, if replacement heifers are kept from him, he will permanently influence the future genetic capability of the cow herd.
The first step may be to choose which sale to attend and purchase bulls at. For today's discussion, lets assume that decision is already made and that you have the sale catalog in hand, preferably before the day of the sale. Which bulls in that catalog should you be most interested in? Doing your homework before the sale may involve ranking the bulls in the catalog based on your criteria so that you can plan which bulls to bid on most aggressively, thus ensuring greater likelihood that you take home your favorites. What criteria should you consider?
Physical appearance is a time-honored selection tool. This isn't really an option at the stage of studying the sale catalog because there probably aren't pictures of all bulls in the catalog and a picture is usually a poor substitute for actually seeing the bulls, so that will have to wait until sale day, or a visit to the seedstock producer before the sale. Additionally, the appearance of any given bull may or may not transmit to his offspring, so other tools need to be considered that will provide better predictive power to the appearance/performance of his offspring. The same is true of most individual bull performance data provided in the catalog. Individual birth weight, weaning weight, etc. may or may not transmit as desired. Do not ignore these data, but realize their predictive power is limited.
In a perfect world, it would be nice to buy bulls for commercial use with proven transmission of superior genetics, but that would require progeny
testing. Progeny testing bulls for commercial use would simply be cost prohibitive. And bulls for sale should be virgins to ensure prevention of bringing home sexually transmitted diseases. The only realistic opportunity to utilize progeny-proven genetics is through AI. Even with the use of AI, the vast majority of commercial producers still need to purchase cleanup bulls.
What is available that is intermediate to appearance of the bulls and progeny tests? The best tools available are the pedigree or predictors based on the pedigree, especially expected progeny differences (EPD), which are predictors of genetics that will be transmitted. While not perfect, EPDs are powerful tools that can be used to make informed bull selection decisions. A concern is that despite their widespread availability in most popular beef breeds, they are probably under utilized. I think there are a couple of common reasons used by those that avoid EPDs. I would like to discuss and try to dispel those reasons:
One concern is that the accuracies are low on the EPDs of young, virgin bulls. This is true, and it is because there is not any progeny data. However, an EPD can still be calculated based on genetic relationships among ancestors and relatives in the pedigree. While this EPD may not be as strong of a predictor as a high-accuracy EPD on a proven AI sire, it is still the most predictive tool available for a young bull. Studying the bull sale catalog becomes important. It will also have the pedigree of each sale bull. Besides considering his own EPD (which are probably low accuracy), look up the EPDs of his sire and grandsires. They will likely be progeny-tested bulls with high accuracy. While this is not a perfect predictor of the young, sale bulls, a thorough examination through the pedigree can start showing relationships. If those relationships fit your genetic goals for your herd, then that bull is probably one to consider bidding on.
Recommended Stories For You
Another concern that is becoming apparent is that there has been rapid expansion of the number of EPDs that are available, especially in the most popular beef breeds. While this is a good thing because it expands the opportunities for selection, I am concerned that some commercial producers are becoming overwhelmed with the vast array of numbers to sort through, which simply causes them to not sort through them at all. Keep in mind that no one is obligated to use all of them. Each producer gets to choose which are important to his or her genetic goals and then ignore the rest. Just be cautious to not become over-focused on only one or two EPDs and ignore the others to the degree that problems creep into your cow herd. There are plenty of examples wherein single-trait selection created rapid progress in the single trait but also rapid deterioration of other traits in the herd (the classic example is singular selection for weaning weight leading to increased birth weight and calving difficulty).
My recommended approach to bull selection at a given sale includes:
1. There are a lot of EPDs, so focus on those for traits that need management and improvement in your herd.
2. Evaluate those EPDs (and other performance data to a degree) based on your specific genetic improvement needs.
3. Mark all the bulls in the catalog that meet your goals.
4. Rank those marked bulls from best to least for your goals and desires.
5. Get to the sale early so you can adjust rankings based on physical appearance. While appearance may or may not be transmitted, they still need structural soundness to travel and mate with your cows.
6. Once the sale starts, buy as high in your ranking as you can