What can breeders do to improve the accuracy of EPDs

You can’t go to a cattle convention or a beef extension talk without hearing about how collecting whole contemporary group data will help you receive more accurate information from the national cattle evaluation.

Typically, you encounter so much information, suggestions, and tips that you don’t even know where to start implementing and improving your own data collection.

It’s overwhelming and you ask yourself, why bother?

But at the end of the day, it’s important to know where your cattle stand to make a profit. For producers looking to capitalize on genetic improvements, data collection and reporting is an important part of their herd management because more informative expected progeny differences and indexes help them select more profitable cattle.

Overall, there are a few factors to consider when submitting information to better predict your animal’s genetic value:

1. What data you’re collecting;

2. How you’re collecting the phenotypic measurement; and

3. How you’re reporting the contemporary group records.

What is a contemporary group?

To get a better understanding of genetics, phenotype (animal measurements) and environment.

The phenotype, like birth weight, weaning weight and such that you’re collecting is a combination of the animal’s environment and genetics, but to isolate the genetic portion of an animal’s phenotype we need to eliminate as much environment as possible.

A contemporary group is the best way to set the environmental effects as equal as possible. Generally defined, CG is a set of calves that are the same age, same sex, managed alike and exposed to the same environment. All the calves in a CG should be given an equal opportunity to perform. Any calves that are treated differently, such as sick, fed or housed differently, twins, or embryo transfer calves would contemporary differently than the rest of the calves.

The environment includes things like the herd, year and season the animal was born, pasture, the amount of milk provided by the calf’s dam, the age of the dam, and the calf’s sex. A CG looks at fair competition as an animal grows, and it’s informed by management information that is reported such as pasture and feeding groups.

The initial CG for a set of calves is created at birth. At weaning time, the date of measurement and the management code break a CG down further, and will likely continue to get smaller as yearling data is reported.

As the calves get older, the CG will naturally get smaller due to culling, injury, sickness, death, or reassignment to a smaller group that reflects different management treatments. When a CG is reported appropriately, it improves the accuracy in EPDs and reduces environmental biases.

Report all the data, all the time

Reporting the whole calf crop and CG is important because genetic predictions improve when complete and accurate performance data is submitted on every calf born in your herd. Incomplete or inaccurate data reduces the reliability of each animal’s EPDs. In addition to more accurate EPDs, the dam’s production record will be current with the association when a calf is reported each year.

Best practices for taking weight measurements: Calibrate scale before weighing, clean scale periodically during the day, take empty body weights, take measurements multiple times and average the numbers and weigh as many animals as you can on one day.

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Weight measurements are more empirical because they don’t require interpretation from the person recording the trait. On the other hand, measurements like dam udder score, body condition score, or feet and leg scores require the person doing the scoring to make a judgment. The best way to remove subjectivity from collecting data is to score using a rubric, be consistent on who collects the score, train, and retrain.