From the State Vet's Office
January Shakes ’Em, February Breaks ’Em and March Takes ’Em
by Dr. Tony Frazier
A downer cow is technically defined as a "non-ambulatory" cow. The term, non-ambulatory, refers to a cow that cannot stand and walk from one place to another under her own strength. Downer cow syndrome may be the result of any number of offending causes.
We learned in veterinary school almost all diseases fall under one of the following categories: degenerative, autoimmune, metabolic, nutritional, neoplastic (tumors), infectious, traumatic or toxic. Diseases from every one of those categories can result in a downer cow. This has long been the source of much frustration to the owner of the cow as well as to the veterinarian.
Cows become non-ambulatory in all months of the year; however, the majority of the downers occur in late winter and early spring. This year may see even more downer cows than in previous years. Typically a combination of age, poor body frame score, stage of gestation or lactation, and a poor plane of nutrition tend to send the cow into a downward spiral from which she may not recover. I would like to briefly discuss some of these contributing factors to the downer cow and how to address them.
Age is not something you can really change. If a cow is 15 years old, she is 15 years old, and should have been sold a few years ago. Depending on who you listen to, if you keep beef brood cows over ten years old in your herd, you are simply rolling the dice. The effects of age obviously vary from cow-to-cow and herd-to-herd. Just as you look at a 60-year-old person and he may appear to be 70 or 50; the difficulty of the miles makes a big difference. Keeping a younger herd will definitely stack the deck in your favor.
Body frame score is often a primary factor in the downer cow. Without going into the spectrum of scores and what describes a 5, 6 or 7, body frame scores can usually be divided into too thin, too fat and just right (in Goldie Locks terminology). Cattle that are too thin going into the winter are prime candidates to become downers, especially if combined with one or more of the other factors. As cattle with poor body frame scores get into late gestation, it becomes increasingly difficult for them to carry around the extra weight of the calf growing inside their uterus. When body condition deteriorates in a cow, it usually takes a deliberate effort to correct the problem.
Grass tetany and milk fever are both metabolic problems worsened by age, nutrition and stage of lactation. Both involve a deficiency of one or a combination of minerals, usually ones in extreme demand by the cow due to lactation. As I mentioned before, not keeping old cows is a major consideration in preventing grass tetany or milk fever. There are many complex factors that may lead to grass tetany or milk fever. These factors include whether the cow is a heavy milker, whether minerals in the fertilizer for the pasture have "tied-up" calcium or magnesium, as well as the individual cow’s susceptibility. Maintaining a good level of nutrition for the herd as well as making a balanced mineral mix available are good tools to keep in the tool box to prevent metabolic diseases.
This year especially, I think is worth mentioning starvation is neither quick nor good, but it is a way to get out of the cattle business. Cattle on a negative plane of nutrition will likely eventually become downers. After the drought summer we went through, much of the hay being fed this winter is not high quality. It is worth noting you can fill a cow up on poor quality hay, and while it will help keep her from blowing away in a windstorm, it will do very little to meet her nutritional needs. If you have poor quality hay, it is essential to supplement with some other type of feed. Winter weather requires a great deal more calories to maintain a cow than other seasons. On cold days and nights, cattle burn calories simply to keep warm. It is necessary to make sure cattle are fed to meet the increased need for energy.
While downer cows may receive treatment and return to normal status, a bottle of glucose, calcium and magnesium are often only temporary fixes for a much larger problem. It is difficult to know whether to treat a cow that gets up but goes down a second or third time. One thing is certain. The longer a cow stays down, the less likely she is to recover. After only a short period, the muscles in the legs become damaged due to the weight of the cow lying down. Most people can relate to sitting in one position for a long time and having a leg "go to sleep." The same thing happens in the cow, but it tends to become much worse with each passing day. Therefore, a downer cow should be treated as quickly as possible to help prevent muscle and nerve damage.
Unfortunately, there is no salvage value to a downer cow. Shortly after the positive BSE cow was found in Washington State in December 2003, USDA ruled non-ambulatory cattle cannot be brought into a slaughter facility. In other words, if a cow cannot walk into the slaughter facility on her own, she cannot be processed. The regulation says "all non-ambulatory cattle are considered adulterated and cannot enter the slaughter facility." This includes cattle that are "Custom—Not For Sale."
Finally, while we will always have downer cattle, there are things we can do to reduce the potential for cattle to become downers.