Clinical and pathologic features of acute bovine liver disease in Australia

Abstract

Acute bovine liver disease (ABLD) is a sporadic hepatic disease affecting cattle in southern Australia, characterized histologically by striking periportal hepatocellular necrosis. The cause of ABLD is unknown; however, the seasonality and acute presentation of outbreaks suggest mycotoxin involvement. We describe here the clinical and pathologic findings of ABLD in 45 naturally affected cattle from 13 outbreaks occurring from 2010 to 2019 in Victoria, Australia. Outbreaks occurred in herds located along the southern coastal plain of Victoria and were observed most frequently in lactating dairy cattle. Clinical signs commonly included a combination of mild photosensitization, progressive neurologic signs, and hypogalactia, which preceded death by ≤ 48 h. All affected animals had marked elevations in activities of glutamate dehydrogenase, aspartate aminotransferase, and gamma-glutamyl transferase. At autopsy, the most common lesions were serosal petechiae and/or gastrointestinal hemorrhage, and hepatomegaly with a pronounced hepatic reticular pattern. The principal histologic lesion was widespread—severe periportal hepatocellular coagulative necrosis and erythrocyte pooling—which often extended to massive necrosis. Lesions in other organs were uncommon. Our study of ABLD suggests involvement of a potent hepatotoxin that is either directly cytopathic or requires bioactivation by periportal-specific enzymes.

Investigation of Weather Triggers Preceding Outbreaks of Acute Bovine Liver Disease in Australia

“…Cattle in the states of Victoria, Tasmania, and occasionally in the south-eastern parts of South Australia are most affected. Affected cattle show non-specific clinical signs of acute hepatic disease, with marked elevations in hepatocellular enzyme activities [2]. Clinical progression is often rapid, with death or euthanasia occurring within 48 h of the onset of clinical signs [2].…”

“…Affected cattle show non-specific clinical signs of acute hepatic disease, with marked elevations in hepatocellular enzyme activities [2]. Clinical progression is often rapid, with death or euthanasia occurring within 48 h of the onset of clinical signs [2]. Histopathologic features include striking acute periportal necrosis, which extends to massive (panlobular) necrosis in a large proportion of cases [2].…”

“…Clinical progression is often rapid, with death or euthanasia occurring within 48 h of the onset of clinical signs [2]. Histopathologic features include striking acute periportal necrosis, which extends to massive (panlobular) necrosis in a large proportion of cases [2]. Histologic differential diagnoses are therefore limited to other causes of periportal to massive hepatocellular necrosis affecting cattle in these regions [2].…”

“…Histopathologic features include striking acute periportal necrosis, which extends to massive (panlobular) necrosis in a large proportion of cases [2]. Histologic differential diagnoses are therefore limited to other causes of periportal to massive hepatocellular necrosis affecting cattle in these regions [2]. These include Cyanophyceae spp.…”

“…[3], amatoxin (Amanita sp., Galerina sp., Lepiota sp.) [4], and copper [5], usually from parenteral administration [2,6,7]. Thus, a diagnosis of ABLD relies on histologic assessment and thorough-onsite examination.…”