Renal hypoplasia and dysplasia in an American miniature foal.

Diagnostic imaging, including computed tomography, of a two-month-old foal with renal failure indicated that its right kidney was probably absent and that its left kidney was abnormal in shape. The foal was stabilised and released, but three days later its clinical signs recurred. Postmortem examination revealed renal hypoplasia and dysplasia, the first reported case of this condition in an American miniature horse.

Endogenous lipid (cholesterol) pneumonia associated with bronchogenic carcinoma in a cat.

An 11-year-old, female domestic longhair was presented for dyspnea, vomiting, and left forelimb lameness. A mass in the left caudal lung lobe was seen on thoracic radiographs. The mass was resected during thoracotomy, and histopathology confirmed a diagnosis of endogenous lipid pneumonia. The cat recovered slowly from surgery and was euthanized 11 days following discharge because of persistent respiratory difficulties. Necropsy findings included lipid pneumonia and bronchogenic carcinoma, with probable tumor metastasis to the small intestine, spleen, kidney, and left triceps muscle.

Macroscopic and microscopic characterization of a uriniferous perirenal pseudocyst in a Domestic Short Hair cat.

The macroscopic and microscopic features of a uriniferous perirenal pseudocyst in a castrated male 12-year-old American Domestic Short Hair cat are characterized. The development in humans and animals of a perirenal pseudocyst due to the accumulation of urine, lymph, or blood is discussed. In the presented case, microscopic evidence suggests that the pseudocyst developed following formation of a split in the kidney capsule. Emphasis is placed on the development of uriniferous pseudocysts and three proposed criteria for their development: trauma, abnormal openings that allow extravasation of urine, or urethral obstruction.

Amebic meningoencephalitis in a sheep.

A 1.5-year-old Suffolk ewe with acute onset of incoordination and blindness unresponsive to antibiotic treatment was examined at necropsy. The meninges were congested, opaque, and thick. Microscopically, focal areas of hypercellularity in the left cortical gray matter and the meninges were observed. The inflammatory response consisted of gliosis and perivascular cuffing (lymphocytes, plasma cells, and variable numbers of eosinophils). An amebic organism in 2 life stages was found in the cerebral parenchyma. Numerous large (15 to 35 microns in diameter) organisms, interpreted as trophozoites, were characterized by vacuolated cytoplasm and small nuclei with a prominent eosinophilic nucleolus (karyosome). The smaller (10 to 17 microns in diameter) encysted stage was surrounded by a capsule-like membrane, and contained a large central body sometimes surrounded by a clear halo. Immunofluorescence studies for amebic antigens were strongly positive for an ameba recently isolated in human beings and baboons (Leptomyxid sp).

Squamous cell carcinoma of the vulva in a cow.

An 8-year-old Holstein cow was evaluated because of a slowly enlarging vulvar mass that had impaired artificial insemination attempts. Vulvar squamous cell carcinoma was diagnosed. Clinical cases of vulvar squamous cell carcinoma have not been as widely reported as those of ocular squamous cell carcinoma in cattle. Treatment modalities for vulvar squamous cell carcinoma have not been as thoroughly investigated as for those of the ocular condition. Cryosurgery and radio-frequency hyperthermia appear to be the optimal therapeutic modalities, each providing up to 90% tumor remission.

Endometrial adenocarcinoma in a mare.

An endometrial adenocarcinoma with metastases to the lung, liver, spleen, mesentery and serosal peritoneal surfaces was found in an 11-year-old Arabian mare. Clinical signs included generalized weight loss, depression, anorexia, ventral edema and abdominal distension. Ascites was due to thrombosis of the caudal vena cava. The diagnosis of endometrial adenocarcinoma was based on the histological appearance of uterine glandular epithelium and the presence of similar tissue in the metastatic tumors.

Probable hypersensitivity vasculitis in a dog.

Allergy immunotherapy (hyposensitization) injections or ibuprofen were implicated as causes of hypersensitivity vasculitis in a dog suffering from probable food allergy. The vasculitis was associated with increased complement component, C3, and resulted in deep, ulcerated draining nodules and plaques on the forelimbs, lateral aspects of the thorax, and thighs. Injections had been given as immunotherapy for suspected atopy. Vasculitis, associated with allergy immunotherapy and increased complement component, C3, as well as with nonsteroidal anti-inflammatory drugs, has been reported in human beings.

Progressive ataxia in a Charolais bull.

A 20-month-old Charolais bull was referred for evaluation of progressive hind limb ataxia. Clinical findings suggested a neuroanatomic lesion caudal to T2. Postmortem histologic examination revealed multifocal, acellular, pale, eosinophilic plaques throughout the cerebellum, which were diagnostic for the disease progressive ataxia of Charolais cattle. This disease is presumed to have a hereditary transmission and is not commonly recognized in the United States.

A comparison of standard femoral head and neck excision and femoral head and neck excision using a biceps femoris muscle flap in the dog.

Sixteen normal 20 to 30 kg dogs had standard femoral head and neck excision (8 dogs) or femoral head and neck excision with interposition of a biceps muscle flap (8 dogs). Lameness lessened at week 6, and did not differ between groups; neither group returned to a completely normal gait. Weightbearing decreased on the operated pelvic limb compared to controls (forceplate analysis). Weightbearing force of the muscle flap dogs was significantly less at weeks 6 and 16 than that of the standard femoral head and neck excision dogs. The operated limb of both groups was shortened; shortening was significantly greater for the muscle flap group. Hip extension was limited in both groups. Both groups had decreased (more acute) hip, stifle, and hock angles measured in standing position. Thigh muscle atrophy was more pronounced in the muscle flap group at week 6. More soft tissue was interposed in the muscle flap group at necropsy compared to the group with standard femoral head and neck excision, but the difference was not statistically significant. Skeletal muscle fibers were present in the interposed fibrous connective tissue of the muscle flap group, and the healed surfaces were smoother than those of the standard femoral head and neck excision group.

Comparison of metrizamide and iohexol for cisternal myelographic examination of dogs.

A double-blind study, using metrizamide, iohexol, or Ringer's solution (control) as cisternal myelographic agents, was performed on 25 dogs. Before myelographic examination was done, each dog was subjected to physical, clinical pathologic, and neurologic examinations, as well as examinations by electroencephalography and computerized tomography. These were repeated 24 hours after completion of the myelographic examination. The group of dogs given metrizamide (group II) had a significantly greater occurrence of seizure activity (6 of 10) than did the control dogs (group I; 0 of 5) or dogs given iohexol (group III; 0 of 10; P less than 0.003). In group II, the CSF microprotein concentration was significantly greater 24 hours after myelography was done than were the values in groups I and III (P less than 0.003). Myelograms of the group II dogs (metrizamide) and group III dogs (iohexol) had similar diagnostic qualities. At 24 hours after myelographic examination was done, computerized tomography scan revealed that each dog given metrizamide and iohexol had myelographic contrast material in the brain and cervical spinal cord parenchyma. Seemingly, iohexol has good diagnostic quality, but is less epileptogenic than metrizamide when used in cervical myelographic examinations of dogs.

Renal medullary crest necrosis associated with phenylbutazone therapy in horses.

Thirty-five cases of renal medullary crest necrosis morphologically similar to the renal papillary necrosis of analgesic nephropathy as described in man and rats are reported in horses receiving maintenance dosages of phenylbutazone. The primary lesion is a well-demarcated focal medullary necrosis resulting in sequestration of fragments of the renal crest. Renal cortical lesions are considered secondary to the medullary necrosis and consist of segmental pallor as a result of tubular dilatation, filtrate retention, and interstitial edema. Ischemia in concert with phenylbutazone is suggested as the etiology. Renal medullary crest necrosis is presented as more appropriate morphological terminology for this lesion in the equine species than renal papillary necrosis as is used in man and rats.

Naturally occurring trypanosomiasis (Chagas' disease) in dogs.

Nine fatal cases of canine American trypanosomiasis (Chagas' disease) were encountered from November, 1972, through November, 1975. Of the 9 cases, 7 occurred in dogs from 5 central Texas counties, and all but one case was diagnosed during the months of September, October, or November. The source of infection was discovered in only one case--that being a doghouse heavily infested with Triatoma lectularius occulta. Each of 6 bugs collected had infective forms of the protozoan, Trypanosoma cruzi. Trypanosomiasis usually is not considered in the differential clinical diagnosis of cardiac dysfunction in man or other mammals in the United States. An antemortem diagnosis was made in only 1 of the 9 dogs, with diagnosis in the remaining dogs being made at necropsy. The predominant microscopic lesion in all dogs was necrotizing granulomatous myocarditis associated with the amastigotes of T cruzi.

A drug-induced cerebrospinal lipodystrophy in the domestic chicken (Gallus domesticus).

A drug-induced lipidosis of the central nervous system of chickens is reported. Membranous cytoplastic neuronal inclusions similar to those seen in Tay-sach's disease in man and in spontaneous or drug-induced disease in swine were seen by electron microscopy. Fat was demonstrated in frozen sections.