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Acta sci. vet. (Impr.); 51(supl.1): Pub. 876, 2023. ilus

Artigo em Inglês | VETINDEX | ID: biblio-1434879

Resumo

Background: Caudal vena cava thrombosis (CVCT) is a serious disease that affects cattle. Due to being commonly a fatal pathology, it causes economic losses for producers and national livestock. Thus, the present study describes the epidemiological, clinical, ultrasonographic imaging and pathological findings in 4 cattle with CVCT attended at the Veterinary Hospital (HV) of the Institute of Veterinary Medicine (IMV) of the Federal University of Pará (UFPA). Cases: The animals were crossbreds of the Gir x Holstein and Jersey x Holstein breeds, aged between 4 and 8 years old, raised in semi-extensive and intensive systems. The main clinical signs were pale mucous membranes, reluctance to move, markedly positive venous pulse, engorged jugular with positive stasis test, and serous to mucopurulent nasal exudation. The auscultation of the lung fields revealed tachypnea, silent areas, wheezing, and pleural friction, in addition to coughing, expiratory dyspnea, mouth breathing, and expiratory grunts. One animal had severe hemoptysis. The ultrasound examination performed on a bovine revealed a circular and dilated caudal vena cava in cross-section. Laboratory tests in 3 cattle revealed anemia, leukocytosis with neutrophil left shift, and increased liver enzymes. At necropsy, all cattle had thrombi in the hepatic segment of the caudal vena cava. In the lung, multiple abscesses and areas of parenchymal consolidation, crateriform areas, as well as thrombi in the arteries were observed. Pleural effusion and ascites were seen in all cattle. Clotted blood was seen in the trachea, bronchi, and on rumen contents of an animal. Histopathological alterations seen in the liver were centrilobular hepatocytes with frequent intensely eosinophilic cytoplasm, and pyknotic, karyorrhexic, or absent nuclei and cell borders barely distinguishable. In the lung were nodular and random formations, with a thick wall of mature connective tissue and a central area full of cellular debris, necrotic cells, and intact and degenerated neutrophils (abscesses). Discussion: The set of diagnostic tools that include epidemiology, clinical signs and clinical examinations, ultrasound, necropsy, and histopathology were efficient in the diagnosis of CVCT. The possible causes that led the animals to develop CVCT were diffuse septic pododermatitis in the medial nail of the right pelvic limb associated with traumatic reticuloabomasitis and liver abscesses. In 1 cow, it was not possible to establish the probable cause of CVCT, but for the other cattle in the present study, the probable causes are in agreement with studies that have shown that this disease can occur as a sequel to several septic conditions such as jugular phlebitis, mastitis, hoof rot, enteritis, pneumonia, traumatic reticulopericarditis, acidosis and rumen laminitis, as well as omphalophlebitis in calves. The tachypnea, serous to purulent nasal exudation, pulmonary wheezing, pleural friction, coughing, and expiratory dyspnea, usually with open mouth breathing and expiratory grunts evidenced in the animals of this study, occurred as a result of embolic abscess pneumonia. The presence of multiple lung abscesses, areas of parenchymal consolidation, crateriform foci, and thrombi in the pulmonary arteries and chronic suppurative pneumonia, found at necropsy of the animals in the present study, are related to the development of a thrombus in the caudal vena cava that detaches and embolizes and lodges in the pulmonary arteries. The histopathological findings in 1 cow are compatible with lesions found at necropsy and draw attention to embolic pneumonia and liver lesions, which, are related to thrombi in pulmonary arteries and abscesses formed from CVCT, as well as venous stasis exerted in the return circulation.

Biblioteca responsável: BR68.1