Scratching the surface: Investigating the prevalence, nature and potential causes of itchy cattle Research team Dr. Brenda Ralston, Dr. Merle Olson, Dr. Denis Nagel and their research teams Collaborators • • •
Alberta Veterinary Laboratories Ltd., Calgary, Alta. Chinook Contract Research, Airdrie, Alta. Lakeland College
Funders • •
Beef Cattle Research Council Alberta Beef Producers
Summary In cattle, pruritus (itching) is a clinical sign of skin disease and is often associated with hair loss, swelling, crusting, and scaling. Severe scratching on fencing and feed equipment are the most common signs a producer observes when cattle have winter hair loss. Itching and hair loss may reduce the value when animals are sold for breeding. The causes of itching can include: 1. ectoparasites (lice, mites) 2. bacterial and fungal pathogens (e.g. ringworm) 3. environmental allergies (plant, fungal, parasitic) 4. environmental irritants (dry air, freezing of skin, chemicals) 5. nutritional deficiencies 6. nutritional toxins (mycotoxins). Western Canadian producers have often thought that itching is associated with infestations with lice. Still, investigations of individual herds by pharmaceutical companies providing topical insecticides such as ivermectin have failed to show lice infestations in treated