Ask The Vet

Skin Conditions Tough To Diagnose

Image by Victoria G. Myers

Q: We have a cow/calf operation, with one group of cows calving in the fall and the other in the spring, allowing us to use one bull. For the past four years, in the fall-calving herd, we have consistently found 1- or 2-week-old calves with a skin condition that resembles mange. One particular cow’s calves have had the condition three of the past four years. It generally begins around the tail and progresses down the back line and the sides. All the hair comes off, and the exposed skin is raw-looking and bleeding in spots. The calf continues to nurse and does not exhibit any symptoms of distress or pain. What are your thoughts as to the cause of this problem?

A: A lot of the skin problems we see in young calves are secondary to scours. The loose stool can cause a moist infection that can spread rapidly. Flies will often lay eggs, and in short order, you have a problem with maggots. But, your description does not fit 100% with this condition.

I can tell you that we’ve seen a lot more dermatitis in cows and calves--often caused by a hypersensitivity to insect bites. Photosensitization can also cause problems like the one you describe. This occurs when there is a substance in the skin that is reactive to sunlight. This can be due to something the calf or cow ate that contains the substance. It most commonly occurs when something damages the liver and impairs an animal’s ability to process and excrete a substance derived from digestion of chlorophyll by microorganisms present in the gastrointestinal tract. White cattle or the white areas of cattle are most often affected.

In your herd’s case, we also must consider the possibility of some genetic component since the problem occurred with calves from the same cow multiple times. Ultimately, a skin biopsy may be required to make a diagnosis.

Q: We have a heifer with a swollen udder. The swelling extends up the body toward her belly button, is soft and feels like bread dough. We are very concerned, as she is close to calving. Is there anything we need to do?

A: This sounds like a condition called udder edema. It is much more common in dairy cows than beef cows but is most common in heifers and heavier milkers. An exact cause is not known, but there may be some impairment of her circulation in the pelvic area because of fetal pressure.

There is often a drop in protein levels in the blood immediately prior to calving, as antibodies are transferred into the colostrum. Proteins act like a sponge to keep fluid in the veins and capillaries, so low levels could cause the condition you describe. High energy rations and legumes have also been implicated in increasing the incidence of udder edema in dairy cattle.

This swelling can prevent the calf from being able to nurse and get adequate colostrum, which can lead to a multitude of problems. So keep a close watch, and give the calf a colostrum replacer if you are concerned it’s not getting what it needs from the dam.

I recommend having your veterinarian examine her to see if udder edema is the problem or if there is some other issue. Diuretics and steroids are usually effective in decreasing swelling in udder edema.

Q: I have a Dexter about 7 years old that has never calved. I am going to cull her finally, but she is acting strange, and I wanted to know if you have any theories as to why. For about a year now, she has been lowing (it seems angrily) and pawing at the ground. She gets aggressive with other cows, especially anytime another female comes into heat. Otherwise, she appears healthy and grazes well, and her coat is fine.

A: I would bet this female has some hormonal issues. That said, we find females that are infertile with no reason we can document for the condition. With her behavior getting worse, there could be a malignant or benign tumor producing an androgenic hormone. Ultimately, culling is what has to be done as she could seriously injure other animals or humans in her current condition.

Please contact your veterinarian for questions pertaining to the health of your herd. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice, but is purely for informational purposes.

Write Dr. Ken McMillan at Ask The Vet, 2204 Lakeshore Dr., Suite 415, Birmingham, AL 35209, or email


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