DNA testing ups your IQ

Feb 8, 2013
by WLJ

We have entered the DNA era in selecting cattle…now what? Most of the breed associations are, in fact, moving in that direction, and over the next several years, tools and traits derived from DNA analysis will continue to expand and the data will become more and more useful. We have already begun to use these traits; however, many cattlemen are not up-to-speed on how to use the results of the DNA analysis.

Taking the environment out of the equation of cattle evaluation, you are measuring the animal’s genetic potential, since the animal’s individual performance is calculated by measuring the performance of each animal compared to his or her contemporaries in a similar environment. Ratios are then derived from this calculation and it is those ratios that currently build the expected progeny differences (EPDs) databases.

These databases have been carrying physical measurements on animals for several decades now, and it is those measurements that allow breed associations to predict an animal’s performance from birth to final stages in life, be it in production or consumption. This is why a newborn calf can carry a full set of EPDs; they are predicted from pedigree measurements and calculations of related animals. These EPDs also carry a low accuracy until the individual animal has data reported, then those EPDs fluctuate accordingly and the accuracy of that particular EPD increases.

Since the DNA analysis is attempting to remove the environment from cattle evaluation, we are essentially removing the need for the contemporary group as well. This makes the playing field even for all sizes of breeders. With DNA, you are comparing one animal to the rest of the breed rather than having the EPDs driven from the ratios within a contemporary group. Having a level playing field is an exciting implication and a major reason for my advocacy of the technology.

When DNA was first being analyzed and proven as an accurate selection tool, the test results were then compared to the EPDs of the animal. Since the EPDs are the most accurate selection tool we currently have, this made perfect sense. In theory, the results of the DNA test should validate the EPDs and vice versa. Where the DNA test becomes useful is selecting outliers in individual traits. For example, we know through sire-testing programs that full brothers can display different traits to different degrees. The usefulness in the DNA is the attempt to identify which brother will display which traits more prominently without having to go through the lengthy and expensive sire-testing programs. This speed in identifying the outlier has the potential to accelerate genetic potentials within that breed.

At this point in the game, these DNA companies have been able to identify areas along the genome that indicate potency towards a certain trait, such as marbling, ribeye area, and birth weight. To clarify, the identification of these traits is not 100 percent accurate; they are merely indicators. Until the technology used to analyze DNA can identify every single gene and how it interacts with other genes, the results of the current DNA test will serve as an indicator for each trait.

I do applaud breed associations for taking another step in the DNA world by reporting the results through the EPDs the animal currently has. This change in the EPDs is aimed at enhancing the individual traits, much like ultrasound has done with carcass traits. In the current system, an animal can be evaluated with the current system we use in evaluating an EPD profile. This is where the term Genomically Enhanced EPDs, or GE EPDSs, comes from.

Much like every aspect of cattle production, input costs become the most inhibiting factor in selecting a DNA test to perform. Currently, a seed stock breeder can test their animals from $30-$75/head for a basic DNA profile. A commercial breeder can purchase a subset of these traits for $10-$20/head. The costs are becoming more economical as the technology is becoming more accurate and more widely used. I believe with a sustainable business model, this trend will help the technology remain a staple in animal evaluation.

The exciting part of this technology is we can actually see how many more markers we have to evaluate the opportunity to identify the interactions they have with each other. This has the ability to increase our IQ in breeding cattle for the consumer. Do I want our product to be as consistent as poultry or pork? No. But this technology has the opportunity to assist decreased levels of inconsistency, which would increase the pleasant eating experiences by the average consumer. That alone is what keeps cattle producers in business. — LOGAN IPSEN