Caracterização epidemiológica, clínica e patológica de melanoma em caprinos.

Abstract

Epidemiological, clinical and pathological characterization of melanoma in goats. Melanomas are malignant neoplasms of melanocytic origin, highly metastatic and can be found in several species of animals and in man. However, it is known that in the goat species it has rarely occurred in the routine. In this way, the objective of this work was to make a retrospective study of goats diagnosed with melanoma in the semiarid region in 2003-2016, sent to the Laboratory of Animal Pathology of the Veterinary Hospital UFCG / LPA-HV. During the study period, 644 goats were necropsied and 89 biopsies were performed, of these 11 animals were diagnosed with melanoma, 6 of them from biopsies and 5 from necropsies. The animals were all from the semiarid region, 10 animals from the State of Paraíba and 1 animal from the State of Pernambuco. Most of the animals were undefined (9/11), had pigmented skin, females (10/11) and age ranging from 2 to 5 years. Clinical signs were varied, unspecific being related to tumor location. Macroscopically, there were masses or blackened nodules on the skin of the nostrils / upper lip (2/11), base of the horn (2/11), mammary gland (2/11), perineum (2/11), anus (1/11), Vulva (1/11) and vagina (1/11). In five cases, regional lymph nodes (2/5), lungs (2/5), liver (2/5), spleen (1/5), kidneys (1/5), uterus (1/5) And ovary (1/5). Microscopically the lesions were similar and were characterized by cells arranged in nests sometimes in mantles, proliferation of neoplastic cells elongated or rounded, pleomorphic, of moderate to marked anisocariasis and anisocariasis, typical and atypical mitosis, and the intracytoplasmic brownish granular pigment was present in All cases. It is concluded that melanoma is a sporadic neoplasia in goats, mainly in females, adult and undefined. It can occur in several regions of the skin, mainly devoid of hairs, causing diverse clinical manifestations, in addition to metastases to regional lymph nodes and parenchymal organs, evolving to the death of the animals or euthanasia. Microscopic aspects were similar and were characterized by malignant neoplasms of melanocytes.