Ideally, every dead animal should be necropsied. But, recognizing that dairy producers and veterinarians are busy, it is more realistic to use a targeted approach.
Target cows that performed poorly or died for unknown reasons. “If you guess that the majority of cows are dying from respiratory problems, and the results from a necropsy show they are dying from something else, this would substantially change the way you treat and manage those cows,” states Garry.
By targeting the necropsies, dairy producers can get a high return on their investment. Studies at Colorado State indicate that at least 50 percent of deaths could be prevented with proper management. Multiplied by the value of a replacement heifer, this is a huge economic opportunity.
Answers can be found in a short amount of time. The average necropsy takes 30 minutes to perform on adult cows, and less time for calves and heifers.
“If the information gained from a necropsy is put to use, it is an invaluable investment because you will be able to reduce your death loss,” explains Garry. The key, he says, is how the information is used.
Dee Griffin, veterinarian with the Great Plains Veterinary Educational Center at the
University of Nebraska, knows first-hand the value of necropsies. “Last fall, we had several cows die from what appeared to be pneumonia. After the necropsy, we learned they were dying from ketosis. In that stage of lactation, ketosis was not something we would have considered. We brought the nutritionist in to analyze the feed, and the ration prescribed was not what arrived from the feed mill. Because of the necropsy, we were able to fix the problem within 48 hours.”
La Luna Dairy, a 1,500-cow operation in Wellington, Colo., has been working with a veterinarian to perform necropsies for more than 10 years. Necropsies are performed on 90 percent of its dead animals. “Very often, we will find something unexpected and occasionally raise more questions than answers,” says owner Jon Slutsky.
Necropsies have given Slutsky insight that he never had before. “We will call our veterinarian out at times we wouldn’t have in the past,” he says. “We also make culling and treatment decisions differently, because we have a heads-up to potential problems.”
Prior to performing necropsies, death loss at La Luna Dairy was as high as 9 percent, which meant the dairy was losing 135 cows per year for unknown reasons. Since implementing necropsies into its management practices, the dairy has been able to reduce death losses to 6 percent and hopes to reach 5 percent this year.