Advantages of Tissue Sampling (TSU)

When you are ranching for profit, you pay special attention to the health of your cattle. At some point, you might need to check the cattle for BVD infection, do a parentage verification, or check genetic selection. For all of these, you will need to take samples of animal tissue to send to a lab for analysis. To ensure it is done efficiently and inexpensively, tools are available that can help you. For example, the Tissue Sampling Unit (TSU) from Allflex, turns collecting tissue samples into a quick and easy task. Let’s look into this tool in more detail.

Tissue sampling
Tissue sampling allows you to collect DNA samples quickly and efficiently

What Is Tissue Sampling?

Tissue sampling makes it easier to collect the animal’s DNA, which you can then send for analysis. Compared to traditional methods of blood or hair sampling, this method is easier and more efficient for your ranch. To take a sample, all you need is to punch the ear of your animal with a tissue sampling unit gun (TSU gun). Place it in a special container and then send this sample of tissue for analysis. You can do this in situations where you would usually use the blood or hair of the animal. This method does not result in stress for the animal and is also very easy. As mentioned above, collecting a small piece of tissue can be useful in such situations as parentage verification, BVD diagnosis, genomic profiling, genetic conditioning, or twin DNA sampling. 

When you are collecting DNA using blood or hair samples, you will need to use a paper card from the lab. It is easy to use but is not automated, so it takes more time to perform. TSU, on the other hand, is a quick and versatile method. It allows you to collect samples from cattle, swine, game, and sheep alike. Ranchers quickly become familiar with the tool, so it does not cause difficulties with tissue collection. If you need to take samples from a lot of heifers, it is better to sample tissue rather than hair or blood. But if you will need to test the animals again after several years, tissue sampling might not be the best option. 

Tissue sampling is a quick method of DNA collection for sheep, cattle, game, and swine
Tissue sampling is a quick method of DNA collection for sheep, cattle, game, and swine

Recording a Sample

Once you collect the sample, you will need to record it. Do this by matching the sample with the ID of the corresponding animal. This is very important. For example, in a situation where you use the tissue for BVD diagnostic, you need to know exactly which animals are sick and which are healthy. For this reason, every sample usually has a barcode, which helps trace it back to the animal using its ID. Many ranchers believe that sampling animals early in life are best. That is because the sample is easy to collect, and the producer can choose the animal’s future if necessary. With heifers free from BVD tested between 8-12 weeks of age, you can decide whether to breed or sell them, for instance.

Why Should You Use a Tissue Sampling Unit?

As a rancher, you know that there are several ways to collect genetic material for analysis. But none of them are as quick and easy as tissue sampling using a special applicator gun. It not only delivers high-quality results, but it is also low-cost and not time-consuming. You can take a sample of tissue with this method from animals of any age. You can do it even right after their first day of life. Apart from that, the applicator is designed in such a way that one sample will be enough material for analysis. When it comes to blood, mucous, or hair samples, you often need to make sure they are adequate before sending them to the lab. And often, this results in having to do the tests again. 

With tissue sampling, the preparations are done for you – you just need to perform the test itself, which is also very easy and does not require any specific knowledge or training. If you restrain the animal before taking the sample, the procedure will not take more than a few seconds. Also, it will cause minimal stress to the animal. Also, because the sampling units are loaded into the applicators, you have a clean sample that will be preserved in the special container. High-quality DNA samples remove the need for retesting and are easy to send to the lab. The container has a seal and has an ID panel and a barcode to maintain the integrity of the sample. 

Connect the sample with the animal’s ID
Connect the sample with the animal’s ID

How to Take a Tissue Sample?

Before taking any samples, make sure to restrain the animal. You can use a headgate or any other method that you find more suitable for your cattle. Even though sampling is very quick, so the animal does not feel stressed, it still implies removing a piece of tissue which can be painful. Once the animal is in place, you will only need an applicator and the tissue units. These are special containers where the tissue will be collected after you pinch the ear with the gun. Place one of the units into the applicator and lock it in the device. Once the unit is the applicator, squeeze the handles to make sure the unit is locked in place properly. Then, you can release the handles and get rid of the plastic clip on the sampling unit. 

If you have followed these steps correctly, you should now be able to take the sample. The best place would be one inch from the side of the animal’s ear. Squeeze the handles quickly and release them just as fast. The sampling is done, and now you can take out the unit and check whether the tissue was collected correctly. If you are not sending the tissue sample immediately for analysis, you can store it up to one year at room temperature, after which it should be frozen. But it is best to have the samples analyzed earlier than that. It is important, especially if you are doing a diagnostic of BVD among your cattle. You can find detailed steps of loading and using the applicator with images in this application guide from Allflex.