Working Ranch Magazine March/April 2025

refrigerated — though not frozen — as soon as possible and shipped cool. It may sound obvious, but when sampling blood, only ever use sterile, single-use needles and be sure the needle is the appropriate size for the vein. Clean the draw site with antiseptic in order to avoid contaminating the sample with bacteria. Similarly, be sure to clean the tissue notching tool between animals with disinfectant and thoroughly rinse before moving on to the next animal. If you’re not sure about sampling, ask your veterinarian or consult an extension agent for guidance. Alternately, there are detailed protocols and often video tutorials provided by test makers and extension services for producer education. The test sorts cattle based on carcass merit, predicting the growth and grad ing potential of the animal (within the Igenity Terminal Index, or ITI) as well as the prediction for days on feed (Igenity Days on Feed index, or DOF). Because carcass traits are so herita ble, they should be some of the most valuable to producers when it comes to data collection and decision-making. How you use that information depends on your operation and your goals. Cow-calf producers that retain ownership would see what animals changes appropriate for the individ ual animal and the overall operation. DNA testing of some members of a herd, typically done with straight forward tissue sampling, is another valuable information source, for the producer and his or her customer. To make it economical, though, it’s rec ommended that you be selective about who gets the test. With replacement heifers, for example, weed out the obvious bottom of the pack and don’t bother testing them. Then, with the DNA results for the rest of the group, you can look for those with the traits that you’ve identified as most benefi cial for your operation and make appro priate retention choices accordingly. One economically useful DNA test now available is the Igenity Feeder DNA test by Neogen.

hat can an ani mal’s tissue or blood tell you? A whole lot, it turns out. While veterinarians

returns results in thirty minutes, com pared to the typical two to seven days return from the laboratory. Early pregnancy diagnosis reduces overall costs by identifying open females faster, therefore is critical to profitable and efficient beef pro duction. Talk to your veterinarian or local extension agent to learn more about the options available to you and which strategy might make the most impact on your operation. TELL ME MORE Pregnancy isn’t the only thing scientists can see in a blood sample. Blood also provides a window into an animal for early disease detection or investigating disease outbreaks, and is frequently used for certain types of herd health monitoring, as well as par entage verification. In addition, blood samples are a way to get an inside look for assessing mineral nutrition, meta bolic state, and nutritional status. What scientists can see in a blood or tissue sample is expanding as our understanding of cattle genetics grows. And technology is allowing results quicker than ever, allowing beef producers to make better man agement decisions more quickly as well. The information, genetic or oth erwise, gleaned from blood and tissue samples allows producers to make

and producers have been using these samples for years for parentage veri fication, pregnancy testing and, more recently, information for Genomic Enhanced-EPDs, the breadth of infor mation now available and the speed at which that information is turned around have increased remarkably in the last five years. Several tests no longer even require a lab — they’re available for use right beside the chute, with results in minutes. Blood and milk sample testing to check for pregnancy, which has been around since the 1980s, is becoming more necessary than ever as the avail ability of large-animal veterinarians who can reliably palpate early-stage pregnancy becomes more limited, the pressure for greater reproductive effi ciency has grown. Across the country, extension services are encouraging producers to employ tests like this to identify open females faster to mark those animals early and not allow them to live “rent-free.” One example is at the University of Kentucky, where the Campbell County Extension Service offered blood sample pregnancy testing. Extension Agent Michelle Simon noted in a 2022 report, “The impor tance of pregnancy diagnosis in cat tle is easily determined by the cost of production… If producers keep cows over the winter that are not bred, they are automatically losing $500 plus the loss of income from the calf.” She fur ther goes on to report that in 2021 and 2022, they conducted more than 900 chute-side pregnancy tests saving “producers a potential of $453,500 over the last two years by confirming the open or bred status of their cows.” The tests typically take from a few minutes to thirty minutes for results to populate. They identify pregnancy by looking for glycoproteins, which are the proteins that placental cells secrete into the mother’s bloodstream during pregnancy. In 2023, IDEXX released two tests that can be used on the farm with rapid results, the Alertys OnFarm Pregnancy Test and the Alertys Rapid Visual Pregnancy Test. The Visual test

The Anatomy of a Good Sample

hat’s the key to accurate results? A good, clean sample. Firstly, understand what

you’re sampling for, who you’re sampling, and how that sample should be handled. For example, pregnancy false positives might occur if a cow or heifer is tested too soon after calving because pregnancy hormones may still be lingering in her blood. Second, always follow the directions of the individual test provided by the company or lab. Does the sample need to be refrigerated or put on ice? It depends on the purpose. If all you’re looking for is pregnancy, then the sample can typically be shipped without special cooling, so long as it will reach the lab in under three days. Conversely, tissue samples should be

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