A case of pediculosis in a beef herd

Abstract

An owner called for hair loss and itching in his beef herd since the last three weeks. Thirty animals were in good general conditions, with a body condition score (BCS) in line with the age and the breed (average BCS 3.5/5), ten animals showed poor coat texture and a BCS < 2.5. The animals were kept into a too small area and dirty pens are with bad natural-lighting. Several fighting has been observed. Some animals were seen waiting for eating. All the animals presented itching, alopecia on head and neck. The animals looked nervous and stressed. Differential diagnosis included pediculosis, mange and parasitic gastroenteritis for animals with poor BCS. Blood, fecal and hair samples were collected in order to evaluate anemia, GI parasites and infestation. In 12/20 cattle sampled, many nuts, nymphs and adult lice were found on microscopic examination, in 8/20 cattle only lice nuts have been visualized. Based on the ratio head:thorax and on the head shape, lice have been identified as Anoplura. The identification of the species resulted in Solenopotes capillatus, because Solenopes spp. presented tubercles carrying spiracles that project from abdominal segments. Solenopotes capillatus is also known as “Little blue cattle louse” and is the most common Solenopotes spp. species that could be found in bovine. No other ectoparasites were found. Microematocrit and TP were normal in all animals. Feces were negative for endoparasites. The owner was strongly encouraged to decrease the number of animals per pen in order to decrease the direct physical contact and the stress due to fighting and feeding competition. Also, removing some of the cover materials and a better storage of the hay, might lead to a better illumination of the all area. Natural lighting not only improves cattle welfare, but directly acts against lice. As soon as the sunlight becomes stronger, lice may lose their comfortable environmental inside the winter hairs (9-11). Another critical point was the cleanness of the pen. Dirty and moisty environmental might increase lice infestation, thus not only a disinfection with specific products, but also providing clean and dry environmental to animals was recommended to the owner. Treatment was made by application of deltamethrin at a dosage of 10 ml/500 kg of body weight. At the follow up the fattening area looked well illuminated. The pens had been cleaned and the animals were organized in the 10 pens (3-4 animals per pen). All the animals presented better condition and looked less stressed. Their coat was less dry and scaly but still presented some alopecia in the most of affected animals. Animals kept under extensive management system were more likely at risk for lice infestation than because poor feeding, overcrowded and stress might occur. This case underlines the importance of good environmental conditions and hygiene, which reduce stress and predisposes less to lice infections.