bluuebunny/crossref_metadata_2025 huggingface dataset:
Pancreatitis Associated with an Adenovirus in a Rhesus Monkey
Authors: Chandler F. W. , Callaway C. S. , Adams S. R.
Published: March 2010

A juvenile Rhesus monkey died suddenly while being conditioned for tissue culture studies. A diagnosis of necrotizing pancreatitis associated with adenovirus was made on the basis of the demonstration by electron microscopy of paracrystalline arrays of viral particles and granular and fibrillar inclusions in necrotic pancreatic acinar cells. This is the first description of necrotizing pancreatitis in a nonhuman primate. Adenovirus should be considered in the etiology of pancreatitis in nonhuman primates.
Tracheal Basement Membrane Thickening in Rhesus Monkeys
Authors: Splitter G. A. , Butcher W. I. , Stevens M. D.
Published: March 2010

Thickened hyaline tracheal membrane similar to that which occurs with several respiratory conditions in man was seen in Rhesus monkeys. The membrane was eosinophilic and up to 50.4 μm thick. Frequently eosinophils and mast cells were seen in the tracheal mucosa and submucosa. Using fluorescent microscopy, IgG, B1C, B1A and albumin were identified in the membrane. Electron microscopy showed that the membrane was composed of 18.8-nm collagen-like fibrils with occasional periodicity. The cause of the thickened hyaline tracheal membrane could not be determined. The changes probably represent a response to mild repeated or continuous tracheal injury owing to a variety of causes. Delineation of the cause of this process in nonhuman primates may help in the understanding of respiratory diseases in man.
Giant Hypertrophic Gastritis of Basenji Dogs
Authors: Van Kruiningen H. J.
Published: March 2010

Giant hypertrophic gastritis is a newly recognized disease of adult Basenji dogs similar to Menetrier's disease of man. It is characterized by weight loss, diarrhea, dry coat, pale membranes, anorexia, raised convoluted rugae in the body of the stomach, palpable fluid- and gas-filled intestines, colonic inflammation, and radiographically demonstrable dilated intestinal loops. Laboratory findings include leukocytosis, neutrophilia, low hemoglobin, hypoalbuminemia, hypobetaglobulinemia, hypergammaglobulinemia, decreased serum fatty acids, hypocholesterolemia, indicanuria, low fecal pH, and increased fecal fat and nitrogen. Four dogs studied had gastritis with hypertrophy and diffuse lymphocytosis and plasmacytosis of the small intestine.
The Pathogenesis of Porcine Rectal Stricture: I. The Naturally Occurring Disease and Its Association with Salmonellosis
Authors: Wilcock B. P. , Olander H. J.
Published: March 2010

Rectal stricture occurred in each of 23 pigs submitted for necropsy from eight Indiana farms. Each stricture was an annular cicatrization of the rectal wall, 2.0-5.0 cm anterior to the anorectal junction. Emaciation, colonic dilatation and compression atrophy of abdominal and thoracic viscera were a result of chronic obstipation and inanition. Most pigs with strictures had severe enteric disease 4-8 weeks before the strictures occurred. Salmonella typhimurium was isolated from seven of the eight groups of pigs examined. Ulcerative proctitis, a possible precursor of rectal stricture, was frequently in pigs with enterocolitis caused by 5. typhimurium.
Demyelination in Mice After Two or Three Infections with Avirulent Semliki Forest Virus
Authors: Chew-Lim May , Suckling A. J. , Webb H. E.
Published: March 2010

Adult mice given two or three intraperitoneal inoculations with avirulent Semliki Forest Virus showed typical lesions of a viral encephalitis similar to those caused by a virulent strain of the virus. Demyelination also was seen in the medulla and in the folia of the cerebellar white matter. Neuronophagia was seen only in mice that had had three successive infections. The repeated inoculations of avirulent virus exacerbates the encephalitis of a single inoculation and causes demyelination. The mice did not have neurological clinical signs except for a short-lived weakness of the hind legs. No central nervous system lesions were seen by the 7th and 8th week after the initial infection and all mice recovered.
Polioencephalomalacia of Dogs with Thiamine Deficiency
Authors: Read D. H. , Jolly R. D. , Alley M. R.
Published: March 2010

A naturally occurring neurological disease occurred in six dogs fed cooked meat. Clinical signs were anorexia, progressive spastic paraparesis, recumbency, convulsions and death. The disease was characterized by bilaterally symmetrical spongy change and necrosis of brainstem nuclei with a lesion distribution pattern similar to that in thiamine deficient foxes and cats. An associated thiamine deficiency was evidenced by decreased thiamine levels in the blood of one dog and in the food of another, and rapid remission of clinical signs in a dog given thiamine hydrochloride. Thermal destruction of thiamine through cooking of the foods probably caused the dietary deficiency.
Neurologic Disease in Naturally Occurring Salmonella choleraesuis Infection in Pigs
Authors: Wilcock B. P. , Olander H. J.
Published: March 2010

A granulomatous meningoencephalomyelitis was seen in 17 feeder pigs submitted for diagnostic evaluation from eight farms. Vasculitis and destructive microgranulomas were widespread in both brain and spinal cord. Occasionally there were microabscesses. Salmonella choleraesuis var. kunzendorf was isolated from six of the eight groups, and there were lesions of acute salmonellosis in all animals examined. In three of the affected herds the principal disease manifestation was neurologic.
Feline Panleukopenia: II. The Relationship of Intestinal Mucosal Cell Proliferation Rates to Viral Infection and Development of Lesions
Authors: Carlson J. H. , Scott F. W.
Published: March 2010

Proliferation rates of small intestinal mucosal cells of noninfected germfree and specific pathogen-free kittens were compared to the incidence of infected cells and microscopic lesions in kittens experimentally infected with panleukopenia virus. Mucosal crypt length, cells per crypt, mitotic index and villous length were greater in specific pathogen-free kittens than in germfree kittens. Crypt cells per unit length and villous length per crypt length ratio were greater in germfree kittens. The cryptal cell proliferation rate of specific pathogen-free kittens was 2.24 times that of germfree kittens. Mucosal crypt length, cell per crypt and villous length were greater in the proximal jejunum than in the midjejunum of kittens within groups. Cell proliferation rates per crypt did not differ between areas of the intestine in kittens within groups. There were more virus-infected cells and lesions in specific pathogen-free kittens than in germfree kittens. The incidence of virus-infected cells and lesions was greater in the proximal jejunum and decreased along the small intestine.
Hepatic Midzonal Necrosis in a Pig Fed Aflatoxin and a Horse Fed Moldy Hay
Authors: McGavin M. D. , Knake R.
Published: March 2010

A 35-kg Duroc pig died 3 days after eating a ration containing aflatoxin B1, B2, G1; and G2. It had hemorrhagic enteritis and extensive midzonal necrosis in the liver. A 13-year-old Quarter-horse that died 2 days after eating moldy hay had hemorrhagic enteritis, fatty degeneration of the myocardium and renal tubules, and extensive total midzonal necrosis of the liver.
Classification of Epithelial Canine Mammary Tumors in a Defined Population
Authors: Monlux A. W. , Roszel J. F. , MacVean D. W. , Palmer T. W.
Published: March 2010

Ductal carcinomas accounted for nearly all metastases seen in epithelial canine mammary tumors submitted to the Tulsa Registry of Canine and Feline Neoplasms in a 4-year period from a defined canine population. Lobular and squamous cell carcinomas were the only other metastatic carcinomas seen. Early ductal carcinoma was used to indicate nonmetastatic ductal carcinoma with a favorable post-surgical prognosis. Benign epithelial tumors were categorized as adenoma, ductal papilloma and squamous cell papilloma. Progressive transformation of well defined adenomas and papillomas to carcinoma was not evident in histologic preparations.

Squamous metaplasia was seen in many ductal papillomas and ductal carcinomas. Inclusion of pseudocartilage and pseudoosteoid and osteoid, cartilage and bone with ductal carcinomas, adenomas and ductal papillomas seemed related to secretions escaping from neoplastic epithelial cells into stroma or between proliferating tumor cells. There was proliferation and perhaps even neoplastic transformation of myoepithelial cells in some of these tumors. Changes in myoepithelium, however, appeared to be secondary to neoplastic transformation of epithelium. Bone and cartilage in these tumors were considered heterotopic with no neoplastic potential.
Globoid Cell Leucodystrophy in Polled Dorset Sheep
Authors: Pritchard D. H. , Napthine D. V. , Sinclair A. J.
Published: March 2010

Globoid cell leucodystrophy (Krabbe's disease) was diagnosed in two Polled Dorset sheep from a stud farm. Clinical signs were hind limb incoordination progressing to tetraplegia. Histologic changes in white matter of the brain were myelin destruction, loss of oligodendroglia, astrogliosis and accumulation of distinctive periodic acid-Schiff (PAS)-positive globoid cells. The activities of galactocerebroside β-galactosidase, the lysosomal enzyme specifically deficient in globoid leucodystrophy, and of three other glycosidase enzymes were compared in brain tissue of one affected and six unaffected sheep. Activities of the three nonspecific glycosidases were similar in all seven brains. Galactocerebrosidase activity was similar in the six control sheep, but in the affected brain was less than 6% of the control mean.
Reversible Dermal Atrophy in a Cat Treated with Phenytoin
Authors: Barthold S. W. , Kaplan B. J. , Schwartz A.
Published: March 2010

Phenytoin, given to a cat in proportions therapeutic for man (5 to 8 mg/kg), induced severe dermal atrophy with excessive fragility of the skin following daily oral administration for 3 weeks. Dermal collagen was depleted, but remaining collagen seemed structurally normal. Upon cessation of phenytoin treatment, the cat recovered. In an effort to establish an association between phenytoin treatment and a dermal collagen disorder, phenytoin treatment was repeated and the dermal lesion confirmed.
Über die Antigenität eines chemisch induzierten neurogenen Sarkoms der Ratte [Antigenicity of a chemically induced neurogenic rat sarcoma—author's trans]
Authors: Elling H. , Stavrou D.
Published: March 2010

Antigenicity of a chemically induced neurogenic rat sarcoma

A neurogenic sarcoma was induced in the plexus brachialis of a male Long-Evans rat by administration of N-methyl-N-nitrosourea in the drinking water. The tumor was established in vitro and designated 76LE-NS-369. Cells from tissue culture grew as tumors when isografted in young rats. 76LE-NS-369 cells did not react with antiserum directed against gliaspecific S-100 protein.

We used the cultured cells as target cells, and found specific antibodies in the sera of tumor-bearing and immunized rats by indirect fluorescent antibody stain and a complement-dependent antibody-mediated microcytotoxicity assay. In immunization experiments, incubation of tumor cells with Vibrio cholerae neuraminidase yielded higher antibody titers than an antigen preparation with untreated cells. Incubation with neuraminidase enhanced the sensitivity of tumor cells to antibody and complement in vitro, whereas trypsinized cells showed complete loss of reactivity with autologous antisera. The specificity of antisera was tested by absorption with tumor, lyophilized rat whole body and rat nerve tissues.
Visna-Maedi-Like Disease Associated with an Ovine Retrovirus Infection in a Corriedale Sheep
Authors: Sheffield W. D. , Narayan O. , Strandberg J. D. , Adams R. J.
Published: March 2010

A visna-maedi-like disease was found in a Corriedale sheep from which a retrovirus sharing the group antigen of visna-progressive pneumonia virus was isolated from lung, brain, and spleen. Clinically, the sheep had acute neurologic signs and dyspnea. Pathologic examination showed lesions similar to both visna and maedi. In the lung, there was a patchy interstitial pneumonia with marked lymphoid hyperplasia. Changes in the central nervous system were necrotizing nonsuppurative encephalitis of the brain stem, poliomyelitis of the cervical cord, and ependymitis and subependymal gliosis of the ventricles. Histologically, the central nervous system lesions seemed to have arisen sequentially, perhaps in response to bursts of virus replication as the agent underwent possible antigenic mutation. The severe lesions in both the central nervous system and lungs suggested a virus strain with dual tropism.
Canine Hepatic Neoplasms: A Clinicopathologic Study
Authors: Patnaik A. K. , Hurvitz A. I. , Lieberman P. H.
Published: March 2010

One hundred ten primary hepatic neoplasms, excluding hematopoietic and vascular tumors, were diagnosed in 12,245 canine necropsies. Included were 55 hepatocellular carcinomas, 24 bile duct carcinomas, 2 combined hepatocellular and cholangiocarcinomas, 15 carcinoids and 14 sarcomas. A majority of the dogs with hepatocellular carcinoma (80%), bile duct carcinoma (65%) and sarcoma (61%) were 10 years old or older; 71% of the dogs with carcinoid were under 10 years old. Hepatocellular carcinoma and sarcoma occurred more often in males, bile duct carcinoma in females, and no sex predisposition was found in dogs with carcinoid. All dogs had hematologic and biochemical abnormalities relating to liver function. The aspartate amino transferase/alanine amino transferase ratio was less than one in cases of hepatocellular carcinoma and bile duct carcinoma, and more than one in cases of carcinoid and sarcoma. A massive lesion in one of the liver lobes was the most common gross morphologic feature in cases of hepatocellular carcinoma and bile duct carcinoma, with the left lateral lobe affected most often. In cases of carcinoid, most of the lesions were diffuse. The most common sites of metastases were lymph nodes and lungs for hepatocellular carcinoma and bile duct carcinoma, lymph nodes and peritoneum for carcinoid, and spleen for sarcoma.
Intestinal Atresia and Stenosis in Animals: A Report of 34 Cases
Authors: van der Gaag I. , Tibboel D.
Published: March 2010

Intestinal atresia was found in 29 animals and stenosis in five. Atresia was found in the duodenum in one pup; in the jejunum in nine calves, two lambs and one piglet; in the ileum in one pup, one lamb and one piglet; and in the colon in one foal, seven calves, one lamb, one piglet and three kittens. Stenosis was found in the duodenum of a foal, in the jejunum in two calves and one pup, and in both the ileum and the colon of a kitten. One lamb showed ilial atresia as well as ileal stenosis.

We classified the atresia as type I, membrane atresia (four cases); type 2, cord atresia (six cases); and type 3, blind-end atresia (19 cases). In the literature and our own study, atresia was found only in the small intestine in puppies, but in foals and kittens it was found only in the colon, Atresia of the colon is more common in animals than in man, but multiple atresia, frequent in man, is rare in animals.
Laryngeal Contact Ulcers in Feedlot Cattle
Authors: Jensen R. , Lauerman L. H. , Braddy P. M. , Horton D. P. , Flack D. E. , Cox M. F. , Einertson N. , Miller G. K. , Rehfeld C. E.
Published: March 2010

Of 30,444 larynges from fattened cattle at three companies, 3,985 (13.1%) had contact ulcers or ulcer scars in the mucous membranes over the vocal processes and medial angles of the arytenoid cartilages. The incidence was higher in cattle fed during fall than in cattle fed during other seasons. We hypothesize: 1. that some feedlot cattle develop acute mucositis from mixed infections with species of Pasteurella, Haemophilus, Mycoplasma, and viruses in the nose, pharynx, and larynx; 2. that reflex coughing and swallowing accelerate the rate of larynx closure; and 3. that the closures erode the swollen membrane over the vocal processes and medial angles of the arytenoid cartilages and thus produce primary contact ulcers.
Die Kaliumhydrogenphosphat-induzierte Nephropathie des Hundes. I. Pathogenese der Tubulusatrophiee [Potassium Hydrogen Phosphate Induced Nephropathy in the Dog. I. Pathogenesis of Tubular Atrophy—author's trans.]
Authors: Schneider P. , Pappritz G. , Müller-Peddinghaus R. , Bauer M. , Lehmann H. , Ueberberg H. , Trautwein G.
Published: March 2010

A nephropathy with severe tubular atrophy was observed in Beagle dogs after oral administration of K2HPO4 for 14 or 38 weeks. We describe the complete lysosomal degradation of atrophying tubular epithelial cells.

During two experiments of 14 and 38 weeks duration, respectively, a total of 15 Beagle dogs received 0.8 g K2HPO4/kg body weight daily with their food. All dogs were examined clinically at regular intervals. Renal biopsies were taken in the fourth week from beagles of the 14-week study. Results were compared with those of control dogs.

At the end of the experiments the animals were killed and necropsies done. Different stains and histochemical reactions were applied to paraffin sections of the kidneys. Acid phosphatase and β-glucuronidase were found on cryostat sections. Kidneys fixed by perfusion of five Beagles from the 38-week study and three Beagles of the 14-week study, and from five control dogs, were examined electron microscopically. Ultrahistochemically, acid phosphatase was demonstrated.

Clinically, the dogs in both experiments vomited, were cachectic, and had elevated creatinine and blood urea nitrogen. Morphologically, qualitatively identical changes were seen, but the renal damage was most marked at 38 weeks. There were disseminated tubular atrophy (usually of the proximal tubules), focal scar tissue and nephrocalcinosis. The following pathogenesis was established for the lesions of the proximal tubule: Tubular atrophy begins with loss of differentiation of epithelial cells. Enzyme histochemistry, ultrahistochemistry and electron microscopy show an increase in autophagic vacuoles and autophagolysosomes. The lysosomal bodies showing fusion enclose large parts of the cytoplasm as the process continues. Complete lysosomal degradation of epithelial cells and extrusion of large lysosomes into the tubular lumen follow. After complete enzymatic digestion of the intratubular detritus, the residue is empty, convoluted and collapsed tubular basement membrane. Atrophic tubular epithelial cells have many organelle-free zones at their base, which contain fine filamentous material resembling that of the basement membrane.

The degradation processes described here may explain why clinically the urinary sediment contains few cylinders and epithelial cells and why proteinuria decreases significantly toward the end of the experiment. So far, it is not clear whether the tubular basement membrane is synthesized by the tubular cells, by fibroblasts or by both cell types. The presence of basement membrane-like material in tubular epithelial cells and in parietal epithelial cells of the glomerulus favors the view that epithelial cells produce the basement membranes and that increased production of basement membrane-like material is a sign of loss of differentiation.
The Effects of Clostridium perfringens Type A Enterotoxin in Shetland Ponies—Clinical, Morphologic and Clinicopathologic Changes
Authors: Ochoa R. , Kern S. R.
Published: March 2010

Severe abdominal pain, classic colic signs and hemorrhagic gastro-entero-cecocolitis were induced in three conventional Shetland ponies by intravenous injection with Clostridium perfringens Type A enterotoxin. Histological examination showed marked congestion, edema and hemorrhage of the large and small intestine and sloughing of the tips of the intestinal villi. Marked vacuolar degeneration of hepatocytes with dilatation of the spaces of Disse also was found. Clinical changes consisted of severe hypoglycemia, markedly increased aspartate aminotransferase levels and leukopenia that occurred rapidly.
An Ultrastructural Study of Spinal Nerve Roots and Dorsal Root Ganglia in Aging Rats with Spontaneous Radiculoneuropathy
Authors: Mitsumori K. , Maita K. , Shirasu Y.
Published: March 2010

The spinal nerve roots and dorsal ganglia of 104- to 135-week-old rats with spontaneous radiculoneuropathy were examined by light and electron microscopy.

Demyelination was common in myelinated fibers of various diameters of both ventral and dorsal roots. The most striking alteration was wide distention of myelin sheaths, which extended throughout the entire internode. The spaces formed between separated lamellae frequently were invaded by macrophages. Subsequent vesicular degeneration of myelin seemed to be mediated by invading macrophages. These processes caused complete myelin destruction, but most axons showed no degenerative changes except for obvious reduction in diameter. Occasionally, there were clumping and partial degradation of neurofilaments and ruptured axolemma in the severely demyelinated axons. A few fibers also were undergoing wallerian-type degeneration, perhaps secondary to the severe demyelinative changes. Remyelinating fibers in various phases of repair were coexistent with markedly demyelinated ones. Demyelinative changes described above also developed within some of these remyelinated internodes.

There were no remarkable changes in neurons of the dorsal root ganglia, though accumulation of lipofuscin was common.

Our findings suggest that the changes in the nerve roots are essentially a primary segmental demyelination in aging rats with radiculoneuropathy.
Ultrastructure of a Feline Extraskeletal Giant Cell Tumor (Malignant Fibrous Histiocytoma)
Authors: Confer A. W. , Enright F. M. , Beard G. B.
Published: March 2010

A subcutaneous extraskeletal giant cell tumor (malignant fibrous histiocytoma) was excised repeatedly from a 9-year-old Domestic Shorthair cat. Ultrastructurally, the mass was composed of fibroblast-like, histiocyte-like, and multinucleated giant cells, and some undifferentiated cells and mononuclear cells intermediate between the fibroblast-like and histiocyte-like cells. Fibroblast-like cells were characterized by abundant well-developed rough endoplasmic reticulum, relatively smooth cytoplasmic membranes, few lysosomal structures, and finely granular chromatin. Histiocyte-like cells resembled immature macrophages. The cell membranes had many villous projections. Rough endoplasmic reticulum varied in quantity. Lysosomes were numerous. Multinucleated giant cells had characteristics of both the fibroblast-like and histiocyte-like cells. No viral particles were seen.
The Subacute Neurotoxicity of Excess Pyridoxine HCl and Clioquinol (5-Chloro-7-Iodo-8-Hydroxyquinoline) in Beagle Dogs. II. Pathology
Authors: Hoover D. M. , Carlton W. W.
Published: March 2010

The lesions caused by excess oral pyridoxine hydrochloride (150 mg/kg body weight/day) and clioquinol (200 mg/kg body weight/day), given individually and in combination to adult Beagle dogs, were evaluated. The experimental period was 100 to 112 days, except that four dogs in each of the clioquinol and combined-treatment groups were killed early because of severe debilitation or neurologic disease, and one dog given both compounds died on the third day of compound administration.

Degenerative neurologic lesions had distribution specific for the compound given. Pyridoxine-treated dogs had lesions limited to tracts and nerves with neuronal bodies of their nerve fibers in the spinal and trigeminal ganglia. Clioquinol-treated dogs had neurologic lesions limited to the central nervous system. The most severe lesions were in the rostral dorsal funiculus and distal aspects of the optic nerve fibers, but minimal to mild degenerative changes also occurred in distal aspects of the corticospinal and spinocerebellar tracts. Dogs given both pyridoxine hydrochloride and clioquinol had a combination of the lesions in dogs given pyridoxine or clioquinol individually. Several dogs given clioquinol or pyridoxine plus clioquinol had extraneural lesions, including myocardial degeneration and thyroidal alterations.
Clinical Changes Caused by the Liver Fluke Metorchis conjunctus in Cats
Authors: Watson T. G. , Croll N. A.
Published: March 2010

Cats infected with metacercariae of the fluke Metorchis conjunctus were followed clinically through their infection. Cats given 200 metacercariae showed few symptoms. All the cats passed ova on the 17th day. Three hundred metacercariae caused diarrhea, icterus, discolored urine, green feces and eosinophilia after 18 to 21 days. Eosinophilia, leucine aminopeptidase and alanine aminotransferase were elevated and remain the best indicators for metorchiasis. The hematological and serological abnormalities resolved rapidly and were absent from cats with chronic infection.

Acute lesions (<32 days) were confined to the biliary trees with extensive epithelial exfoliation, fibrosis, and pus from necrosis, tissue feeding by the worms and pressure atrophy. Chronic infections (32 to 150 days) caused hyperplasia of the bile epithelium, proliferation of connective tissues, and fibrosis of the perilobular areas. Intense eosinophilic infiltrates were replaced by mononuclear cells. Granuloma formation around an ovum was seen in one cat 719 days after infection. Adult worms established preferentially in the left lateral lobe and never in the caudal lobe. No gall bladder involvement was found even in heavy infections.
Pathogenesis of Liver Lesions in Mice following a Primary Infection with Ascaris suum
Authors: Bindseil E.
Published: March 2010

The development of liver lesions in mice infected with Ascaris suum is described and compared to the lesions in pigs. The findings suggest that liver necroses in mice are initially periacinar (centrilobular), caused by anoxia resulting from a vascular obstruction by the A. suum larvae located in the sinusoids; and that the lesions in pigs following a primary infection have a different pathogenesis. It is concluded that mice are unsuitable models for studying the pathogenesis of A. suum-induced liver lesions in pigs.
Leukocyte-Dependent Platelet Vasoactive Amine Release and Immune Complex Deposition in African Swine Fever
Authors: Slauson D. O. , Sanchez-Vizcaino J. M.
Published: March 2010

Fifteen pigs were inoculated with African swine fever virus in a study of the pathogenesis of the disease. All pigs surviving the first two weeks developed high circulating antibody titers against African swine fever virus and persistent viremia. Hemolytic complement levels declined to 50 to 70 hemolytic complement 50 (CH50) units/ml from mean preinoculation levels of 120 CH50 units/ml. Immune deposits consisting of African swine fever antigen, host immunoglobulin G, and native C3 were found in the glomeruli of surviving pigs. All pigs surviving two weeks after inoculation developed leukocyte-bound antibody functionally characteristic of immunoglobulin E (IgE). Antigen-specific degranulation of antibody-coated leukocytes produced secondary platelet aggregation and vasoactive amine release. The results suggest that the IgE-basophil-platelet loop acting via amplification by leukocyte-derived platelet-activating factor participates in the immune complex deposition process in African swine fever.
Ocular Lesions in Mink Affected with Aleutian Disease
Authors: Hadlow W. J.
Published: March 2010

Uveitis, characterized by infiltrates of lymphocytes and plasma cells, was the principal ocular lesion in 122 sapphire and pastel mink affected with experimental Aleutian disease. It was present to various degrees in all but five mink examined five to 164 weeks after inoculation (intraperitoneal or intranasal) with any of four North American strains of Aleutian disease virus. The uveitis, mostly iridocyclitis, was accompanied often by protein-rich fluid in the anterior chamber and less often by fibrin and cells in the vitreous body. Cellular infiltration of the limbus, seldom pronounced, also occurred in about 20% of the mink. In 11 mink with moderate or severe uveitis, the retina was detached by pools of protein-rich fluid. Infiltrates of lymphocytes, plasma cells, and a few histiocytes often were found in the orbital soft tissues, occasionally in association with retrobulbar arteritis. In general, the ocular lesions were more severe in sapphire than in pastel mink. The uveitis accompanies glomerulonephritis, the principal lesion of Aleutian disease, much more regularly than do several other lesions of the disease. Like the glomerulonephritis, it probably results from the deposition of circulating immune complexes.
Granular Basal Cell Tumors in the Skin of Three Dogs: A Distinct Histopathologic Entity
Authors: Seiler R. J.
Published: March 2010

Granular cell variants of cutaneous basal cell tumors from three dogs are described. These tumors resemble a granular cell variant of basal cell tumor (carcinoma) in man. The tumors are characterized by classical basal cells as well as granular cells with numerous cytoplasmic granules. These granules are cytoplasmic vacuoles 0.3 μm to 1.5 μm that seem to be secondary lysosomes; they usually contain many small (42 nm), membrane-bound vesicles. No natural, non-neoplastic counterpart of these granular cells is known to exist in the skin, and the significance of the production and accumulation of the small vesicles is not known. The cytoplasmic granules, and their contents, resemble the granules of granular cell “myoblastoma” although granular basal cells are of epithelial origin.
Spontaneous Cardiac Tumors in Eight Rats
Authors: Robertson J. L. , Garman R. H. , Fowler E. H.
Published: March 2010

Spontaneous cardiac neoplasms were diagnosed in one Sprague-Dawley and seven Fischer 344 rats ranging in age from eight months to two years. All eight neoplasms were diagnosed as neurilemmomas. One neoplasm was composed of dense Antoni type A tissue with Verocay body formation, while seven others were composed principally of loose Antoni type B tissue. No specific site predilection was found.
Pulmonary Atresia with Dextroposition of the Aorta and Ventricular Septal Defect in Three Arabian Foals
Authors: Vitums A. , Bayly W. M.
Published: March 2010

Three Arabian male foals were presented with cyanosis, heart murmur, and exercise intolerance. Results of clinical evaluation suggested a tentative diagnosis of ventricular septal defect in conjunction with malformations of the great arteries. Each foal had a poor prognosis and was killed at the owners' requests. At necropsy, the malformed hearts of the three foals were virtually identical. Each heart had a large defect in the upper interventricular septum. The aorta originated from the hypertrophied right ventricle and partially overrode the ventricular septal defect. The aortic ostium was guarded by three semilunar valvules. The position of the valvules and the ostia of the coronary arteries was abnormal. The pulmonary arteries arose from the persistent ductus arteriosus. The pulmonary trunk was reduced to a thin, fibrous cord extending from a short and narrow persistent ductus arteriosus to the level of the semilunar valve, where it fused with the wall of the aorta. No communication of the atretic pulmonary trunk with the cavity of the right ventricle was seen.
Calcium Phosphate Deposition Disease in Great Danes
Authors: Woodard J. C. , Shields R. P. , Aldrich H. C. , Carter R. L.
Published: March 2010

A new clinicopathologic syndrome, possibly familial, in Great Dane dogs, resembles the familial childhood variant of calcium pyrophosphate dihydrate deposit disease in man, except that the mineral deposits were composed of amorphous calcium phosphate or hydroxyapatite rather than pyrophosphate. The syndrome was characterized clinically by paraplegia and incoordination in very young puppies which was caused by concentric constriction of the posterior cervical spinal cord. Canal stenosis resulted from dorsal displacement of the seventh cervical vertebra and deformation of the vertebral articular processes. Mineral deposition in the diarthrodial joints of the axial skeleton could be seen on radiographs of weanling puppies, and the appendicular skeleton became involved as the dogs matured. Periarticular mineralization of the limbs was associated with shorter bones, a thin cortex, abnormal bone curvature, and increased medullary trabeculae. Bone alterations were associated with abnormalities of the growth plate, which had focal areas of cartilage calcification. Soft tissue mineralization, seen in all dogs, was a primary feature of the disease process. Serum calcium concentrations were within the normal range, but serum phosphorus concentrations were decreased.
Spontaneous Rat Malignant Tumors of Fibrohistiocytic Origin: An Ultrastructural Study
Authors: Greaves P. , Martin J.-M. , Masson M.-T.
Published: March 2010

The ultrastructural features of a spontaneous malignant fibrous histiocytoma and three malignant histiocytomas in Sprague-Dawley rats are described. The ultrastructural features of the malignant histiocytomas (or histiocytic sarcomas) support origin from cells of the monocyte series. The histogenesis of more fibrous tumors (fibrous histiocytomas) remains uncertain.
Neuronal and Generalized Ceroid-Lipofuscinosis in a Cocker Spaniel
Authors: Wilkie J. S. Nimmo , Hudson E. B.
Published: March 2010

An 18-month-old cocker spaniel with a progressive central nervous system disorder had neuronal ceroid-lipofuscinosis and storage of these pigments in intestinal, blood vessel, and splenic smooth muscle and in pancreatic, hepatic, and renal parenchymal cells. The disease resembles that documented in four other dogs of this breed. No cause was identified in our dog, but possible pathogenetic mechanisms are discussed.
An Epizootic of Diffuse Glomerulonephritis in White Perch (Roccus americanus) from a Heavily Polluted Industrial Basin in Lake Ontario
Authors: Ferguson H. W. , Moccia R. D. , Down N. E.
Published: March 2010

Examination of 43 white perch from a heavily polluted water basin showed all had severe diffuse glomerulonephritis. There were fibrinoid necrosis of tuft vessels, especially the afferent and efferent arterioles, and thickened basement membranes which ultrastructurally contained dense deposits in a subendothelial location.

None of these lesions was found in white bass, a closely related species, from the same source nor in white perch from other relatively nonpolluted sites in Lake Ontario or Lake Erie. This is a dramatic example of a rare lesion in fish and possibly represents an immune-complex mediated response to an environmental pollutant.
Intracranial Epidermoid Cysts in Three Dogs
Authors: Kornegay J. N. , Gorgacz E. J.
Published: March 2010

Intracranial epidermoid cysts were identified within the fourth ventricle of three dogs. The cysts measured up to 2.5 cm in diameter, were lined by stratified squamous epithelium, and contained intraluminal keratinaceous debris. Secondary compression of the medulla oblongata and cerebellum caused neurologic dysfunction in two dogs; the cyst was an incidental finding in the other dog. Similarities between these dogs and three previously reported intracranial epidermoid cysts in dogs included an apparent predilection for young dogs and involvement of the cerebellopontine angle, fourth ventricle, or both.
Eperythrozoon suis in Naturally Infected Pigs: A Light and Electron Microscopic Study
Authors: Pospischil A. , Hoffmann R.
Published: March 2010

The light and electron microscopic characteristics of natural infections with Eperythrozoon suis are reported. E. suis are enclosed by a single membrane, and they reach a length of up to 600 nm and a diameter of 375 to 500 nm. Neither distinct organelles nor nuclear structures appear in the parasites cytoplasm. They replicate by binary fission, and have close contact with red blood cells without showing any signs of membrane alteration. Massive phagocytosis of whole red blood cells not parasitized by E. suis occurs in spleen and lymph nodes.
Renal Lesions in MRL Mice
Authors: Kolaja G. J. , Fast P. E.
Published: March 2010

Female MRL-Mp- lpr/ lpr mice spontaneously develop autoimmune disease at three to five months of age and die most commonly from immune complex glomerulonephritis. Kidneys of two-month-old females appeared nearly normal by electron microscopy, and glomerular deposits of IgG and complement component 3 (C3) barely were detectable. In five-month-old females, immunofluorescence revealed numerous deposits of IgG and C3; glomerular mesangial cells were hypertrophic and hyperplastic and contained electron-dense material. There were subepithelial and subendothelial deposits of electron-dense material with swelling of epithelial cell cytoplasm. This disease has many features similar to the immune complex glomerulonephritis observed in New Zealand Black and White hybrid mice and in man.
Feline Ovarian Neoplasms
Authors: Gelberg H. B. , McEntee K.
Published: March 2010

Primary ovarian neoplasms from 22 cats were described. A single cat had tumors of epithelial origin—bilateral cystadenomas. Seven animals had germ cell tumors—dysgerminomas or teratomas; two cats had bilateral tumors. Fourteen animals had neoplasms of sex cord-stromal origin—granulosa cell tumors and interstitial gland tumors. Four cats with granulosa cell tumors had clinical evidence of hormonal disturbance.
Choroidal Melanomas in Dogs
Authors: Dubielzig R. R. , Aguirre G. D. , Gross S. L. , Diters R. W.
Published: March 2010

The clinical and morphological features of intraocular melanocytic masses that originated in the choroid of five dogs were compared. Two of the cases had been reported previously and the authors have examined the pathological material. Histologically, the choroidal melanocytic tumors had several features in common and appeared to be entities distinct from melanocytic tumors of the anterior uveal tract or the epibulbar region. The tumors were well-delineated with tapered edges. They occurred in the posterior quadrant and two tumors had infiltrated the optic nerve. The tumors contained plump, straplike polyhedral cells, with minimal nuclear anaplasia and no mitotic figures. The retina overlying the tumor mass was detached, and the retinal pigment epithelium in this area was swollen and contained intracytoplasmic autofluorescent lipopigment. In two cases, the basement membrane of the retinal epithelium was disrupted by the tumor and pigmented cells infiltrated into the retina, the subretinal space, and the posterior chamber. In one case, retinal detachment was complete and accompanied by intraocular hemorrhage. Melanocytic tumors of the canine choroid have features in common with choroidal nevus and melanocytoma in human eyes.
Quantitative Morphology of Peracute Pulmonary Lesions in Swine Induced byHaemophilus pleuropneumoniae
Authors: Bertram T. A.
Published: March 2010

Twenty-seven six-week-old cesarean-derived, colostrum-deprived pigs were inoculated intratracheally with an isolate of Haemophilus pleuropneumoniae serotype 5 (principles) of high virulence (I-200) or low virulence (B-8) or phosphate buffered saline (controls). Pigs given I-200 had severe serofibrinous pleuropneumonia at three hours after inoculation; two of three pigs were dead by 24 hours after inoculation. Interalveolar septa in the caudal lung lobes were 41% thicker than septa from control pigs at three hours after inoculation and 79% thicker by 24 hours after inoculation. Interalveolar septal capillaries in caudal lung lobes were 10.2% larger than control capillaries at three hours after inoculation and 25.6% larger by 24 hours after inoculation. Interalveolar septal capillary platelet volume was greater than the platelet volume of controls; 70% of these platelets were aggregated. There was severe diffuse alveolar, interalveolar septal, and interlobular septal edema at three hours after inoculation with fibrin, neutrophils, and macrophages present in later samples. Thirty-three percent of the lung parenchyma was necrotic at 24 hours after inoculation. Endothelial cell degeneration was generally mild, but necrotic in regions of pulmonary infarction. Pigs inoculated with the B-8 isolate did not develop marked macroscopic lesions at any sampling time. Interalveolar septa were 18% thicker than controls nine hours after inoculation and 5% thicker at six and 24 hours after inoculation. Capillary platelet volume was greatest at nine hours after inoculation with 50% of these platelets aggregated; 30% of the platelet volume was aggregated at the 24-hour sample period. Moderate diffuse pulmonary and interlobular septal edema was present at three, six, and nine hours after inoculation, but absent 24 hours after inoculation. Intravascular macrophages were present in the six, nine, and 24-hour lung samples in both B-8 and I-200 inoculated pigs. These cells were adherent to interalveolar septal capillary endothelial cells and contained phagocytized cellular debris and fibrin. These results indicate the early effects of H., pleuropneumoniae infection involve macrophage and platelet activation, and a marked increase in interalveolar septal capillary permeability.
Morphogenesis of Fusarium sp-Induced Tibial Dyschondroplasia in Chickens
Authors: Haynes J. S. , Walser M. M. , Lawler E. M.
Published: March 2010

Tgibial dyschondroplasia was induced in female broiler chicks by the incorporation of 2% Fusarium roseum “Alaska” culture into their starter ration. Chicks were placed on this diet at one day of age and maintained until they were killed at four days or one week. Proximal tibial physes were grossly thickened into cone-shaped masses of cartilage by one week of age. Microscopically, lesions were in both ages of treated chickens and were characterized by thickening of the transitional zone which was especially prominent in the center of the growth plate. This zone was unmineralized, avascular, and contained chondrocytes which were crenated and densely eosinophilic. The cartilage matrix was pale and contained some patchy eosinophilic foci.

Four growth plates with tibial dyschondroplasia and four normal growth plates from each of the four-day and one-week-old age groups were evaluated based on the following parameters: number of metaphyseal vascular sprouts, distance between the proliferative/transitional junction and the tip of the metaphyseal vascular sprouts, width of the tips of the metaphyseal sprouts, distance between tips of adjacent metaphyseal vascular sprouts, and number of perforating vessels in the proliferative zone. The distance between the proliferative/transitional junction and the metaphyseal sprout tips was greatly increased (p < 0.01) in the affected four-day and one-week-old chickens compared to age-matched controls. Fusarium sp-induced tibial dyschondroplasia morphologically resembles spontaneous and chloride-induced tibial dyschondroplasia and tibial dyschondroplasia may, therefore, represent a common end-point lesion derived by several pathogenetic mechanisms.
Cytochemical Characterization of Feline Leukemic Cells
Authors: Facklam N. R. , Kociba G. J.
Published: March 2010

Hematopoietic cells in blood and/or bone marrow from 23 leukemic cats and ten control cats were characterized using a battery of cytochemical enzyme stains. The results of cytochemical staining led to modification of diagnosis based on clinical, hematologic and histopathologic findings in four (17%) of the leukemias. Sudan black-13 and chloroacetate esterase served as granulocytic markers in both the control and leukemic groups. Peroxidase activity was seen in the granulocytes and monocytes of control animals but not in the blasts of leukemic cats. Diffuse alpha naphthyl butyrate esterase staining marked monocytes in both control and leukemic animals. Cytochemical staining was found to be a valuable aid in the classification of leukemias in the cat.
Naturally Occurring Lesions in Some Endocrine Glands of Laboratory Maintained Baboons (Papio sp.)
Authors: Skelton-Stroud P. N. , Ishmael J.
Published: March 2010

The pituitary gland was examined from 623 immature baboons ( Papio cynocephalus and Papio anubis). Findings included microscopic cysts in the pars distalis (132), pars intermedia (two) and pars nervosa (one). In 641 necropsies five cases of unilateral thyroid glands were noted. Microscopic thyroid lesions included ectopic thymus (328), minor lymphocytic infiltrates (14) and cysts (two). Parathyroid lesions consisted of ectopic thymus (73) and cysts (24). Dilated capillaries in the islets of Langerhans was the only microscopic change seen in the endocrine pancreas. All lesions generally occurred in both untreated control and treated baboons at similar incidences. They were considered to be naturally occurring, a part of the “background” pathology of these endocrine glands in immature baboons.
Identification of Parathyroid Hormone-related Protein in Canine Apocrine Adenocarcinoma of the Anal Sac
Authors: Rosol T. J. , Capen C. C. , Danks J. A. , Suva L. J. , Steinmeyer C. L. , Hayman J. , Ebeling P. R. , Martin T. J.
Published: March 2010

The presence of parathyroid hormone-related protein (PTHrP) in the apocrine adenocarcinoma tumor line (CAC-8) derived from a hypercalcemic dog was demonstrated by western and northern blot analyses. Western blots of CAC-8 tumor extracts revealed a major protein with a molecular weight of approximately 18,000 daltons that cross-reacted with antiserum to human PTHrP. Northern blots demonstrated multiple-sized messenger RNA transcripts in CAC-8 that hybridized to a full-length cDNA probe to human PTHrP. Adenocarcinomas derived from apocrine glands of the anal sac also were stained immunohistochemically for antigens that cross-react with antiserum to human PTHrP. The tumor line (CAC-8) maintained in nude mice stained positively for PTHrP in 13 of 24 tumors. Three of ten apocrine adenocarcinomas from dogs with hypercalcemia stained for PTHrP, whereas zero of ten tumors were positive from normocalcemic dogs. Normal canine epidermal keratinocytes and areas of squamous metaplasia in a perianal gland carcinoma also were positive for PTHrP. These data demonstrated that canine tissues contained a homologue to human PTHrP that likely is important in the pathogenesis of humoral hypercalcemia of malignancy.
Effects of Mononuclear Cell Leukemia on Altered Hepatocellular Foci in Fischer 344 Rats
Authors: Harada T. , Maronpot R. R. , Morris R. W. , Boorman G. A.
Published: March 2010

Quantitative stereologic analyses were conducted on hematoxylin and eosin-stained liver sections to investigate the potential effects of the presence of mononuclear cell leukemia in Fischer 344 rats on the occurrence of altered hepatocellular foci (AHF). The study consisted of 132 male and 144 female rats taken from control groups at the termination of seven, 2-year National Toxicology Program (NTP) carcinogenicity studies. A minimum of 10 male and 10 female rats were killed at 6, 9, 12, 15, and 18 months into the seven NTP studies to assess progressive development of AHF. At the end of the studies, 43 males and 35 females had histologic evidence of mononuclear cell leukemia in the liver. There were no differences in the morphologic features of AHF between leukemic and non-leukemic rats; however, there was a decreased incidence of clear AHF in both sexes and in basophilic, vacuolated, and mixed-cell AHF in males. Stereologic analysis revealed that there was also a 40 to 73% reduction in the density of basophilic, clear, vacuolated, and mixed-cell AHF in male rats with leukemia and a 31 and 70% reduction in basophilic and clear AHF, respectively, in females with leukemia. The number of eosinophilic AHF was statistically unchanged in both sexes. The eosinophilic AHF, however, were 2.3 times larger and occupied a 4.3-fold greater volume fraction of the liver in leukemic male rats. Changes in the incidence and density of AHF were directly associated with the severity of the leukemia. It is postulated that the high incidence of spontaneous mononuclear cell leukemia in carcinogenicity studies using Fischer 344 rats may cause the regression of most types of AHF, may coincidentally provide a selective growth advantage for eosinophilic AHF in male rats, and may make the determination of a weak hepatocar-cinogenic effect more difficult.