It’s Often A Puzzle When A Cow Goes Down

Downer cows have been a concern for farmers and veterinarians almost since the beginning of time.

Typically, a downer cow surprises the farmer. Often a perfectly healthy cow with no presenting history is suddenly found down and unable to rise.

Because cattle, especially mature ones, are such heavy beasts, several complications can ensue, even when the animal has only been down a short time. Pressure sores, stiff muscles from trying to rise, or cattle becoming spread-eagled are common sequelae, or after-effects, of this condition. It is these complications the veterinarian must also treat in order to arrive at a favourable outcome.

With in-house blood testing now available at most veterinary clinics, several tests may be performed on downer cattle to determine the cause. Often “milk fever” is suspected, but deficiencies of either calcium, phosphorus or magnesium resemble one another. With dairy cattle, true “milk fever” results from a shortage of calcium – generally at parturition, when the demand for milk and thus calcium is greatest. Beef cattle can have milk fevers show up at different times either before calving or late into the lactation.

Often poor mineral utilization or improper feeding is the root cause. Today, veterinarians often take a blood sample to test for those three minerals. If deficient, then the diagnosis is made and treatment initiated to alleviate the situation. In my experience, the grass tetany downer from magnesium deficiency is less likely to recover once down. Phosphorus leads to the proverbial creeper cow, which can take a long time to get up. Any cow diagnosed with a mineral deficiency could potentially be the tip of the iceberg. The rest of the herd should be closely scrutinized. You may want to have random blood tests done to confirm the herd status and prevent other cases from developing.

INJURIES

Injuries to the neck or peripheral nerves can cause downer animals, and these present a diagnostic challenge to your veterinarian. Once an animal is down, doing a thorough clinical exam can be difficult. It’s difficult to diagnose lameness or trauma when the animal isn’t ambulatory, so it’s a challenge to determine if a blown stifle (knee) or broken leg is the cause. The alternative is to roll the animal over in order to closely examine all four legs. Lightning strikes, where the animal has survived but the peripheral nerves are damaged, may also be the cause of a downer cow.

With parturition, a difficult birthing can cause pressure on the obturator nerves where they run through the pelvis, resulting in knuckling and weakness to the hind end. If caught early enough, anti-inflammatory drugs may help significantly. One must be careful though – bad mastitis; metritis (infected uterus), or cases of tetanus brought on by retained placentas can fool even experienced practitioners. They can occur just after calving and, if sick enough, cows will be unable to rise simply because of weakness and toxemia. Any condition, which results in dehydration: septicemias or toxemias may result in downer animals. This may come on suddenly or occur over several days. If cattle appear sick and depressed, a large number of maladies will cause enough weakness or toxemia to create a downer situation. Severe electrolyte imbalances (for example, too much potassium in the bloodstream) can cause cattle to go down. Again most of these electrolytes can be tested for by your veterinarian to ensure the proper ailment is being treated.

Very excitable cattle can also go down if they get out and run for a considerable period. The cause is muscle damage, which is not unlike white muscle disease in young calves. This is called “capture myopathy” and happens when zoo animals are captured. Selenium may help but once down, the prognosis is poor.

IMMEDIATE ATTENTION

As you can see, downers are caused by a multitude of medical conditions – most with entirely different treatments. While some treatment results in a very favourable prognosis, others do not.

The important thing is having your downers looked at immediately and to determine the cause. In the meantime, provide soft footing to prevent pressure sores developing. Roll the downers side to side several times daily to help prevent further nerve damage. Hobbling the feet together to avoid splay legging and, where indicated, anti-inflammatory drugs, may also be in order.

Of course, the essentials of life – good-quality water and feed – must be provided. Shade on very hot days is essential. Watch for fly strike around the rectal and vaginal areas.

Some cases such as broken legs or stifle injuries may warrant emergency slaughter, so do not rush in and treat unless the exact cause is known. The transport of large downers is really frowned upon today, so it’s best to conduct an emergency slaughter right on site.

Hip lifters and slings can be employed to lift cattle but I only suggest this if certain criteria are met. Cattle must be trying to rise and when lifted must bear some weight themselves, otherwise there is no point in lifting. Only lift for 15 to 20 minutes twice daily. The hip lifters also cause muscle bruising, so you want the benefits to outweigh the negatives. Certain practitioners are having some success with acupuncture for the nerve-damaged cases.

I am hopeful this article has lessened the frustration and mystique associated with dealing with downer cattle. Patience is a virtue.

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roy lewis

dvm

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Downershavemanycausesandit’simportant todeterminewhat’sgonewrong.

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