Polioencephalomalacia in Buffaloes in the Amazon Biome

SIMPLE SUMMARY: The buffalo industry has great importance in the state of Pará, within the Amazon biome, contributing to society in economic and cultural ways. For this reason, it is necessary to understand the disorders that affect this species, such as polioencephalomalacia (PEM), which has not been reported in the Brazilian literature. This is the first study about PEM in buffalo in the Amazon biome. This work describes five disease cases in buffaloes, presenting their clinical, macroscopic and histopathological findings. ABSTRACT: The epidemiological and clinical pathological aspects of polioencephalomalacia (PEM) in five buffaloes in the Amazon biome are described. Epidemiological data were obtained during the clinical visit in which buffalos were submitted to an examination of the nervous system. The diagnosis of PEM was based on epidemiological, clinical–pathological, and histopathological findings, similar to findings in other ruminants. In the clinical examination, all buffaloes had a body score between 2.5 and 3 (scale from 1 to 5), with decreased alertness, postural changes, marked hypermetria when stimulated to move, total or partial blindness demonstrated by colliding with the corral structures, head pressing and circumduction of the hindquarters when supported on the thoracic limbs, opisthotonos, muscle tremors, convulsions, paddling movements, sialorrhea, decrease in palpebral and pupillary reflexes, and eyeball rotation placing the pupillary slit in a vertical position. At necropsy, mild lesions characterized by edema and flattening of the cerebral convolutions were observed. A histopathological examination showed laminar necrosis of the cerebral cortex. The cause of PEM in the studied buffaloes was not established, which indicates the need for further studies to elucidate this disease in the species, particularly in the Amazon region.