Estudo comparativo do hemograma de peixe-boi-amazônico (Trichechus inunguis) realizado por microscopia óptica e por analizador hematológico automático calibrado no perfil equino

Abstract

The Amazonian manatee (Trichechus inunguis) is an aquatic mammal of great ecological and conservation importance, whose clinical evaluation in captivity relies on reliable laboratory tests, particularly the complete blood count. Given the lack of automated hematology analyzers specifically calibrated for this species, this study aimed to compare hematological results obtained by optical microscopy (manual method) and by an automated hematology analyzer calibrated with an equine profile. Two captive T. inunguis individuals from Macapá, Amapá, Brazil, were evaluated. Blood samples were collected and analyzed using both methods, with results expressed as mean ± standard deviation. Due to the limited sample size, the adopted analysis was a descriptive comparison, focusing on analytical precision and absolute differences between methods. The automated method showed higher analytical precision, characterized by lower standard deviation values. However, marked differences were observed between methods for several hematological parameters, particularly platelet estimation and leukocyte counts, indicating low concordance and lack of interchangeability. Erythrocyte parameters were more consistent with reference values reported in the literature, especially when assessed by the manual method. It is concluded that, although the automated analyzer calibrated with an equine profile demonstrates good repeatability, its use in T. inunguis should be interpreted with caution and always complemented by microscopic evaluation, highlighting the need for species-specific validation.