Sarna demodécica bovina em sistema de produção tradicional em ambiente semiárido.

Abstract

Bovine demodicosis is a disease caused by Demodex bovis. This mite is usually lodged in the sebaceous glands and hair follicles. Clinically, it can occur in two forms: the chronic subclinical form and the generalized form. In the semi-arid region of Paraiba, it is common to notice the occurrence of this type of mange in periods when the herd is found on a low body score. This research aimed to evaluate the correlation between demodectic mange and weight gain, as well as the correlation between demodectic mange and clinical aspects, in Sindhi animals in the months corresponding to the rainy season and dry season of the year. In total, a sample of 33 animals, 23 females and 10 males, aged 7 to 36 months, were used from the Sindhi herd belonging to the Federal University of Campina Grande (UFCG). The weighing, clinical examinations and collections of biological material were performed on the same dates, sequentially, in each of the 33 animals of the sample, once a month, in the rainy and dry quarters. In the clinical examinations performed before each collection, the presence or absence of whitish spots and cutaneous lesions were observed, such as: papules that develop into nodules located on the surfaces of the limbs, head, neck and scapular region. The size of these whitish were also evaluated. The clinical examination carried out during the study found that about 90% of the animals examined showed disease characteristic manifestations in relation to lesions on the skin. However, the presence of nodules in the animals was not observed, only clear spots with bristled and bounded edges hairs were observed, distributed in different parts of the animal's body. It was observed that the middle-type spot is predominant in both sexes, whereas the regions most affected are the thoracic limb and the cervical region. It was also observed that, in the relation animal weight to eggs per gram (EPG), the animals that presented a higher EPG also showed a lower weight gain in the rainy season and a greater loss of weight in the dry period, when compared to animals with low EPG.