Safeguarding public and animal health

You are here: VLA Home Page | Diseases | Psoroptic mange | Diagnosis

Psoroptic mange in cattle

Information for veterinary surgeons and farmers

How is it diagnosed?

Correct diagnosis with laboratory confirmation is essential.

Initially, look for mites to collect using a hand lens. The mites are up to 0.75mm in length and are present all over the lesion, not just at the edge. They appear dark in colour (in contrast to the mites of sheep scab) due to feeding on the blood exudate.

You can collect a skin scrape by using a scalpel blade held at right angles to the skin. Scab material should also be collected. The material should be transported in a container (e.g. a universal) to the laboratory.

Direct microscopy is normally sufficient for identification as there are usually large numbers of mites. A potassium hydroxide digest may be necessary if there are only a few mites.

The Psoroptes sp. mites are oval with pointed mouthparts. All of the legs project beyond the body. The pedicels (at the end of the first, second and fourth pairs of legs in female and first, second and third pairs of legs in the male) are jointed and end with funnel-shaped suckers.