Ultrasonographic diagnosis: Cranial vena cava thrombosis in a cow

A 5-year-old Hereford cow was donated to Oregon State University, College o f Veterinary Medicine, Two weeks before presentation the cow was treated by a left flank laparotomy to correct a uterine torsion that revealed an exce ssive amount of abdominal fluid and a full term dead fetus. Ultrasonographi c evaluation of the right cranioventral thoracic cavity was performed owing to physical examination (muffled heart sounds, areas of silence) and thora cocentesis findings suggestive of pleuritis, Ultrasonography revealed hypoe choic pleural effusion and a mass of mixed echogenicity visible within the right atrial lumen extending into the cranial vena cava, A diagnosis of cra nial vena cava thrombosis was demonstrated at necropsy, The clinical, ultra sonographic, and pathological features of this less common condition (crani al vena cava thrombosis) in cattle are discussed.