Lesões melanocíticas em suínos abatidos para consumo

Extracutaneous Melanotic Melanoma with Nervous System Involvement in a Buffalo (Bubalus bubalis)

Melanomas are tumors arising from externally uncontrolled melanocytes that produce varying amounts of melanin. In this study, we report a case of melanoma with neurological impairment without evidence of cutaneous neoplastic lesions in an adult buffalo in the state of Pará, Brazil. Clinically, the buffalo exhibited apathy, decreased mandibular tone, and occasionally an open mouth with motor incoordination, and eventually succumbed to the condition. Necropsy revealed multifocal tumor masses in the brain, pituitary gland, trigeminal ganglion, and spinal cord. The neoplastic cells showed strong positive signals for vimentin, Melan-A, PNL-2, and SOX10. The diagnosis was made via necropsy, histopathology, and positive immunostaining for Melan-A and PNL-2, which are specific markers for melanocyte identification.

Neoplasms in Domestic Ruminants and Swine: A Systematic Literature Review

BACKGROUND

Due to the limited information and lack of studies on neoplasms in domestic ruminants, i.e., cattle, sheep, and goats, and domestic swine, the objective of the present study was to systematically review the scientific literature to verify the occurrence, type, organ system, and organs most affected by neoplasms in these animals.

METHODS

The recommendations of the PRISMA methodology were followed for the elaboration of this study. The research consisted of a systematic review of neoplasms in domestic cattle, sheep, goats, and swine.

RESULTS

The number of neoplasms found was 1873. The most affected organ system was the integumentary system with 35.0%, followed in descending order by the alimentary system with 16.90%, the hematopoietic system with 13.50%, the special senses (i.e., eyes and ears) with 10.51%, the female and male genital systems with 7.31%, the urinary system with 4.38%, the liver and biliary system with 3.152%, the endocrine glands with 3.91%, the respiratory system with 2.67%, the nervous system with 2.35%, bones and joints with 0.43%, muscles and tendons with 0.37%, the cardiovascular system with 0.21%, and the pancreas with 0.16%. Of the animals with neoplasms studied, cattle were affected in 69.80% of cases, goats in 10.52%, sheep in 10.46%, and swine in 9.18%. In all species, the most frequent neoplasms were squamous cell carcinomas in ruminants, while melanoma was the most frequent in swine. Few studies carried out in slaughterhouses were found, and the existing ones referred to cattle and swine. No data were found on economic losses with carcass condemnation.

CONCLUSIONS

In view of the above, it is necessary to carry out extensive and detailed studies that provide knowledge about the impact of neoplasms on the production and condemnation of carcasses in domestic cattle, sheep, goats, and swine and the respective risk factors.

Melanin bleaching with potassium permanganate for melanocytic lesions diagnosis in veterinary medicine

ABSTRACT The aim of this study was to microscopically re-evaluate the melanocytic lesions diagnoses established by the Animal Pathology Laboratory of the Federal University of Uberlândia, in the state of Minas Gerais, Brazil, over a period of eleven years; in addition, to perform a comparative analysis between the conventional histopathological (CH) method and the use of the melanin bleaching (MB) technique with potassium permanganate, sulfuric acid, and oxalic acid solutions. The results of the MB method presented a disagreement in 24.32% of the diagnosis previously by CH, with low agreement (61.0%) and low Kappa coefficient (0.2267). Melanoma was the most frequent lesion, more frequent in elderly and non-breed female dogs. The most frequent melanoma location was in the cutaneous tissue. The presence or absence of a pagetoid spread in cutaneous samples, distribution of melanin, pattern of cell layout, cell morphology, degree of cellular atypia, and the number of mitoses verified after MB were the most important criteria to confirm the diagnosis of malignancy or benignity of the lesions. Evaluating pathologists considered MB to be essential for the majority of diagnoses and an efficient complementary method for the diagnosis of melanocytic lesions, even in cases with a moderate degree of pigmentation.

Melanose multicêntrica em frango de corte: relato de caso

RESUMO Melanoblastos podem migrar de forma errática durante a embriogênese, gerando um quadro conhecido como melanose. São raros os estudos envolvendo melanose com acometimento múltiplo dos órgãos. Objetivou-se descrever um caso de melanose multicêntrica em frango de corte que gerou condenação do animal ao abate. Foram encaminhadas ao Laboratório de Patologia Animal da Universidade Federal do Espírito Santo para avaliação histopatológica amostras de diversos órgãos de uma ave de corte da linhagem Cobb de 48-49 dias de idade. Esse animal foi condenado na linha de inspeção por apresentar áreas multifocais enegrecidas. Ao exame microscópico, observou-se melanina multifocal variando de moderada a intensa quantidade em todos os órgãos acometidos com lesões enegrecidas na macroscopia. As áreas pigmentadas foram negativas para a coloração especial de azul da Prússia e não foram encontradas células neoplásicas. A pigmentação da pele em aves comercializadas no Ocidente é rara, pois a característica de pele clara foi selecionada por meio de melhoramento genético, mas pouco se sabe sobre quais mutações desencadeiam melanose nas linhagens selecionadas para não apresentar pigmentação. A ave apresentou melanose multicêntrica e tal alteração não compromete a função dos órgãos acometidos nem representa risco para a saúde humana, no entanto, devido ao aspecto macroscópico, os órgãos que apresentam tal lesão foram condenados para consumo humano.