CAHFS Connection - October 2024

Avian

Inclusion Body Hepatitis (IBH) was diagnosed in a group of 19-day-old broiler chickens with a history of increased mortality. On gross examination, all birds had enlarged, mottled, pale tan to red and hemorrgagic livers. On microscopic examination, there was hepatic necrosis with occasional large basophilic viral inclusions within hepatocyte nuclei. Several of the birds also had gizzard erosions. PCR detected fowl adenovirus, commonly known as IBH virus.

Fowl cholera and necrotic enteritis were diagnosed in 11-week-old, farmed chukar partridges experiencing a sudden increase in mortality. Gross findings included hydropericardium and ascites, miliary tan hepatic foci, mottled and congested livers, and mottled spleens. The duodenum was distended and the mucosa was covered by a necrohemorrhagic pseudomembrane. Microscopically, there was necrotizing hepatitis and enteritis. Pasteurella multocida serovar 1 (Hha 1597) was isolated from livers and spleens and was also isolated from a liver swab pool by PCR. Clostridium perfringens was isolated from the intestine and also detected by immunohistochemistry.

Bovine

Klebsiella pneumoniae mastitis was diagnosed in two, 5-6-year-old Holstein cows that died three days after drying off. Affected cows had been milking 50-60 lbs./day at dry off. Tissues submitted from field necropsies revealed severe, multifocal suppurative mastitis. K. pneumoniae was isolated from the mammary glands and found in the lung or liver of each cow supporting secondary bacteremia/septicemia prior to death. This is one of the two most common bacteria found in mastitis developing shortly after dry cow treatment. 

Epizootic bovine abortion (EBA) caused the abortion of a late-term Angus fetus. Gross exam revealed edema in the thymus and lung, petechia and congestion of the thymus, swollen and slightly nodular liver, swollen spleen, and generalized enlarged lymph nodes. Typical histologic lesions were found and EBA ELISA was positive on fetal fluid, which also had elevated immunoglobulin of 593mg/dl, typical of EBA infection.

Equine

Lymphoma was diagnosed in a 20-year-old, Warmblood gelding horse presented for necropsy after a few months’ history of weight loss and respiratory signs followed by death. There was a large mass encircling and infiltrating the pulmonary artery, aorta, and esophagus, and compressing the lungs. There were also multifocal, smaller masses infiltrating the heart, along with hydrothorax and hydropericardium. Histopathology confirmed lymphoma, one of the most common malignant neoplasms in horses.

Small Ruminant

Coccidiosis was the cause of death of a 6-week-old Nigerian dwarf goat kid doe. Two of 5 kids in the group had a less than 24-hour history of anorexia, weakness, and pale mucous membranes before death. Necropsy of the one submitted carcass revealed severe segmental enteritis with raised nodular foci, which histologically contained numerous coccidia. The cecum and colon had watery dark red content and the rectum had poorly formed dark brown to red feces. Large numbers of coccidian oocysts were seen in the feces on flotation.

Wildlife

Anticoagulant rodenticide intoxication was diagnosed in a coyote that was bleeding from the eyes and had ataxia. At necropsy, subcutaneous hemorrhages were observed on the shoulders, abdomen, and limbs. The brain had subdural and intraparenchymal hemorrhages. There was unilateral exophthalmos and bilateral hyphema. A concentration of 2,000 ppb of chlorophacinone, a first-generation anticoagulant rodenticide, was detected in the liver.