The main objective of the present study was to know the rate of occurrence of melanocytic lesions (melanosis, melanocytoma and melanoma) in pigs slaughtered for consumption and to identify possible patterns of differentiation and a macroscopic classification of these lesions. To this end, we proceeded to the collection of melanocytic lesions in a slaughterhouse during 8 months, and its macroscopic and microscopic evaluation. The results of this study demonstrated that melanosis were the most often found melanocytic lesions (74.04%) and that for tumors, melanomas (malignant) were the most frequent (21.15%) compared to melanocytomas (benign) (4.81%). By comparative analysis of macroscopic and microscopic characteristics we found that it is not always possible, with a macroscopic evaluation, to distinguish between these lesions (melanosis, melanocytoma and melanoma). However, in this study we identified some features suggestive of malignancy such as: size exceeding 2.5cm, the presence of ulceration, the release of black pigment and the presence of a black staining of the regional lymph node. Therefore, it is extremely important to make a careful and systematic observation of these lesions, with the evaluation of their characteristics, since the sanitary decision is different if they are melanosis, malignant tumors or benign tumors.
pigs; melanosis; melanocytoma; melanoma; slaugtherhouse
