The improvements that dairy herds have seen in the last several years are not natural consequences of time nor are they accidental. Every improvement within the dairy industry has been the result of deliberate decisions. Using management software and modern science, dairymen have made changes that have been thoughtful, purposeful, and sometimes even risky, but the returns on their investment have been well established.
In the last seven decades, dairymen have seen vast improvements among their herds. “While we may be accustomed to constant improvement over time, it is not guaranteed,” said Dr. John B. Cole, Acting Research Leader at the Animal Genomics and Improvement Laboratory. He also states that every improvement in the dairy industry should be credited to data, tools (like the ones that Amelicor offers), management practices, dedicated employees, and genetics programs. In fact, since 1957 half of the increase in production is due to genetic improvements and half is due to better management practices.
Take A Look At The Whole Picture
Genetic testing on dairy herds has been around for many, many years. According to Dr. Cole, not too long ago the formula went something like this: select for traits that are easily passed on and manage the traits that are more affected by their environment. But what was learned was that by focusing too much on the most valuable traits – such as milk yield, other traits were adversely affected and impacted production. So for genetic selection to truly work you have to look at the whole picture.
Because there is no guarantee that populations will improve overtime, the decisions made have to be the right decisions. Every decision made in the past only lead to more information by tracking the results. By consistently collecting and analyzing the conditions of the results, better decisions are made in the future. By sharing that data so others could benefit, great improvements in populations have been made over time.
To make the right decisions requires a lot of data and working together narrows the margin of error. Jordan Leak with Twin Ridge Genetics (an Idaho business at the forefront of bovine genetics) says, “You really cannot afford to milk a cow that is not going to be the very best cow you have.” And that’s what Genomics does, it eliminates the guessing game by using genetic data to quickly improve your herd. But how does it work? Well, there are a few factors that influence genetic change.
Factors That Affect Genetic Change
Four factors that affect genetic change and can be illustrated through the following simplified equation to show the relationship between the factors:
| Accuracy of Selection | x | Selection Intensity | x | Genetic Variation | = | Genetic Change |
| Genetic Interval | ||||||
- Reliability - This refers to the accuracy of selecting animals that are genetically superior for specific traits. This has traditionally been based on evaluation techniques and parentage results, but Genomics helps to increase our certainty by evaluating the actual genetic makeup of an individual cow. Josh Wright of Twin Ridge Genetics said “Becoming more efficient . . . this is what genomics is doing for us. It’s helping [you] pick your lead animals instead of using a bull from a neighbor that said ‘Hey, I got a bull out of this cow, the cow is really good.’”
- Selection Intensity - This has to do with how selective we are when using breeding stock for the next generation. The more intense the selection process, the more superior a group of animals is. Intense selection can improve a herd quickly with the help of genomics. Twin Ridge Genetics encourages dairymen to avoid being idle and simple milking cows that they think are more efficient and take selection seriously.
- Genetic Variance - This shows the differences among animals that are controlled by genetic factors. While this can be looked at as a fixed property of a particular breed, the heritability of a trait and can be seriously influenced by inbreeding, outcrossing, or crossbreeding.
- Generation Interval - This is the average age of a parent when their offspring are born. While Genomics can’t speed up the time it takes for a parent to mature and have offspring, it can cut the time in half to prove that the offspring will be productive.
According to Dr. Cole, the main factor to understand when making selections to improve your herd is the relationship between heritability and environment.
When increasing selection intensity of your herd Jordan Leak from Twin Ridge Genetics gave some good advice: “The first commitment you have to make is making sure your facilities and management is to the point where you will be able to take advantage of genetics.” Next, “you really have to be cognizant of what you want. If you want a herd that milks hard, you will get it, but it might come at a cost to something else. It’s really important to have a balanced attack and a plan [a vision] in place that you stick to and follow. There are trade-offs for everything . . . you have to understand that there are positive and negative correlations for every trait.”
Dr. Cole’s presentation showed that in order to really take advantage of genetics, you have to realize that management is the first thing to address. Once your management practices – including tracking and evaluating the day to day operations, are in place, you have to understand the correlations that exist between every trait. Dr. Cole gave the example “you can think about the challenges we had with fertility over the last 20 years where we paid a lot of attention to improving [milk] yield and didn’t pay very much attention to fertility . . . and that caused problems.”
Why Genomics Is Important
You will never lose your work when you make genetic improvements in your herd. Dr. Cole said, “We can gather tremendous amounts of information only from the genotype. We then use that information to drive genetic gains that are cumulative. Even if the heritability is small – even if we are making a little bit of progress each year of selection - The important thing to remember is that, the change doesn’t go away.”
The wonderful thing about improvements made with genomics is that as Jordan Leak said, “Genetic progress maintains the speed that you use it.” Unlike changes you can make with management, such as better feeding practices . . . as soon as you get an employee who is not as dedicated, those changes will go away.
Genomics gives you an opportunity to improve your herd at their core. The information isn’t based on assumptions but is based on solid data. By taking the time to realize the benefits of genomic data you can improve your production and in turn, profits, in a relatively short amount of time.
It doesn’t take much to convince anyone of the benefits of using Genomics. The ability to breed based on positive traits to increase production and decrease detrimental traits is a no brainer. Genomics will continue to change and improve the dairy industry as long as those involved will continue to act on new information. But it’s important to remember that no amount of scientific data will make up for poorly managed dairies. Every influential change that we’ve seen has been the result of deliberate decisions. If we can continue this pattern in genetics as well as in good management practices we will continue to see more productive herds, healthier cows, and provide better product for our consumers.