CAHFS Connection - August 2026

Managing Editor: Kerry Ballinger 
Design Editor: Lucy Gomes  
Contributors:  Cassie Powers • Francisco Uzal • Javier Asin Ros • Patricia Blanchard • Pernille Joergensen • Robert Moeller

Announcements

The California Animal Health and Food Safety (CAHFS) Turlock Laboratory is excited to announce the opening of our new facility on July 20, 2026 at 830 Dianne Drive, Turlock, CA 95380.

The move also marks an important expansion of services, as the new CAHFS-Turlock will be able to provide necropsy services for mammalian species in addition to its established poultry diagnostic program. This new facility will jointly house CDFA and CAHFS staff. The phone number for the CAHFS-Turlock laboratory is (209) 634-5837.

General

Aquatic

Fin rot was diagnosed in an adult female koi fish. The animal had a history of an abnormal tail fin, lethargy, and anorexia followed by death. On gross evaluation the margins of the caudal fin were dark grey to brown (Fig. 1). On microscopic evaluation numerous bacteria and water molds were identified in the tail skin. Fin rot is a bacterial or fungal infection that causes a fish's fins and tail to decay. It is usually triggered by stress, poor water quality, or injury.

Avian

Trichomoniasis was identified in a group of juvenile finches with a history of weight loss. There were no lesions on gross evaluation. Histologically, there was moderate to marked esophagitis. Embedded within the esophageal mucosa, were numerous protozoal organisms that stained positive for Trichomonas spp. on immunohistochemistry. Avian trichomoniasis is a contagious disease of the upper digestive tract of birds caused by the protozoan parasite Trichomonas gallinae. It causes severe inflammation and ulcers that make breathing and swallowing difficult. It can lead to weight loss and starvation.

 

Renal carcinoma and bacterial nephritis were diagnosed in a one-year-old male parakeet with a history of scissored beak, poor body condition, and diarrhea, in a flock with multiple sick birds. On gross examination, the kidneys were enlarged and segmentally replaced by a multilobulated, dark red to brown, 3.5 cm x 1 cm x 1 cm mass. On microscopic exam, the kidney mass was consistent with a renal carcinoma (Fig. 2), accompanied by multifocal bacterial abscesses. Renal tumors are common in young to middle-aged male budgerigars. The most common clinical sign is unilateral or bilateral leg lameness resulting from nerve compression by the tumor. Large numbers of Escherichia coli and moderate numbers of Enterococcus faecalis were isolated from the kidney abscesses.

Bovine

Bronchopneumonia and ventricular septal defect (VSD) were diagnosed in tissues from a 2–4-week-old calf. On gross evaluation all lung lobes were firm, dark pink to red, covered by a thin mat of fibrin and had multifocal abscesses. Microscopic evaluation and ancillary testing confirmed a diagnosis of bronchopneumonia caused by Mycoplasma bovis and bovine coronavirus. Additionally, the heart was enlarged and rounded (Fig. 3) and had a 4 cm diameter VSD communicating both ventricles. VSDs can lead to poor growth, lethargy, respiratory distress, and high mortality in calves.

Lagomorph

Rabbit hemorrhagic disease caused by rabbit hemorrhagic disease virus 2 (RHDV2; Lagovirus europaeus) was diagnosed in a 3-year-old male Holland Lop rabbit. This was the third rabbit that died in four weeks, and multiple rabbits in this group were reported to have died over the course of a few months. On necropsy, the rabbit had an enlarged pale tan liver with rounded margins that fell apart easily when handled. On histology, there was massive hepatic necrosis (Fig. 4). Lagovirus antigen was detected on liver by immunohistochemistry (Fig. 5), and RHDV2 PCR was positive. Rabbit hemorrhagic disease is a highly contagious and fatal disease that causes sudden death in both domestic and wild rabbits and jackrabbits/hares.

Pigs/Porcine

Actinobacillus pleuropneumoniae-induced pleuropneumonia was diagnosed in two pigs from a farm where approximately 50% of a group of ~100 recently purchased, 12-week-old pigs developed lethargy, fever, and cough.  Twenty-three pigs died over three days. Some pigs developed purple ears prior to death. Gross examination revealed hemorrhagic and fibrinous pneumonia or pleuropneumonia involving primarily the middle and caudal lung lobes.  Microscopic evaluation was typical of acute A. pleuropneumoniae infection. This microorganism was isolated from the lungs of both pigs submitted.  Testing for porcine respiratory and reproductive syndrome virus and porcine circovirus was negative in both pigs. A. pleuropneumoniae is a common severe respiratory pathogen of pigs between six weeks and six months of age and can be a primary cause of pneumonia.

Small Ruminants

Poison hemlock (Conium maculatum) intoxication was the cause of death of a Boer buck that died after 36 hours of weakness and disorientation. The buck was part of a brush-clearing herd in which other goats had similar clinical signs. Lesions were minimal and non-specific, and included pulmonary congestion and edema, and epicardial petechiae. Coniine, the main toxin of poison hemlock, was detected in the rumen contents via an alkaloid screen. Acute poison hemlock intoxication may not be associated with specific gross or histologic lesions, as the toxin causes sudden neuromuscular paralysis and death by asphyxiation.

A thymoma was diagnosed in a six-year-old Toggenburg goat with a history of being acutely unable to stand. On necropsy, there was a multilobulated mass within the mediastinum (Fig. 6). On histopathology, this mass was composed of neoplastic epithelial cells that stained positive for cytokeratin on immunohistochemistry. Thymomas are common tumors of the thymus in goats. They predominantly occur in goats between 3-12 years of age. Although they can be an incidental finding, they can cause severe clinical signs, including respiratory distress or skin lesions.

Holiday Schedule

No holidays this month.

Employment Opportunities

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