bluuebunny/crossref_metadata_2025 huggingface dataset:
Granulomatous Epididymitis Related to Rhodotorula glutinis Infection in a Dog
Authors: Kadota K. , Uchida K. , Nagatomo T. , Goto Y. , Shinjo T. , Hasegawa T. , Ogawa H. , Yamaguchi R. , Tateyama S.
Published: January 2010

A 4-year-old, male Great Dane dog developed severe swelling of the scrotum on 9 December 1991, and the testes and epididymides were removed surgically on 12 December 1992. The cut surface of the epididymides consisted of hard connective tissue and several small abcesses with slight hemorrhage. Histopathologically, the seminiferous tubules in the testes had only a few spermatogenic cells, but Sertoli cells were well preserved. Both epididymides consisted entirely of a proliferation of fibrous connective tissue, and only a few ducts deferens containing cell debris, neutrophils, and macrophages in the lumina were present. In all lesions of the epididymides, the macrophages contained periodic acid–Schiff– and Grocott's silver–positive round granules, 5-8 μm in diameter. Microbiologically, smooth salmon-pink colonies consisting of ovoidal yeast, about 10 μm in diameter, were isolated from the samples of epididymides but not from those of the testes. The isolated yeast had microbiological characteristics of Rhodotorula glutinis. From these observations, we diagnosed the present case as granulomatous epididymitis due to Rhodotorula infection.
Systemic Mastocytosis in a Goat
Authors: Khan K. N. M. , Sagartz J. E. , Koenig G. , Tanaka K.
Published: January 2010

Systemic mastocytosis was diagnosed in a 4-year-old, female Nubian goat. Clinically, the animal was depressed and had severe macrocytic hypochromic anemia and leukopenia. Postmortem examination revealed neoplastic mast cells invading the heart, lung, liver, spleen, lymph nodes, and bone marrow. Eosinophils were frequently admixed with infiltrating mast cells in all organs. Using routine light microscopy, histochemistry, and transmission electron microscopy, metachromatic and periodic acid—Schiff–positive granules were identified within the cytoplasm of neoplastic mast cells. Erythrophagocytosis was observed in some neoplastic cells, although its contribution to the anemia was not clear. This report represents the first description of mast cell neoplasia in the goat.
Angioleiomyoma of the Nasopharynx in a Dog
Authors: Carpenter James L. , Hamilton Terrance A.
Published: January 2010

A polypoid angioleiomyoma was surgically removed from the nasopharynx of a 1-year-old, male golden retriever. The polypoid mass recurred 4 months later and was again excised. There was no sign of regrowth 13 months postoperatively. This is, apparently, the first reported angioleiomyoma occurring in the dog.
Hepatic Coccidiosis Associated with Hepatic Necrosis in a Goat
Authors: Schafer K. A. , Stevenson G. W. , Kazacos K. R.
Published: January 2010

Hepatic coccidiosis, usually caused by a member of the genus Eimeria, is common in rabbits but rare in other mammals. We describe the first reported case of naturally occurring hepatic coccidiosis in a goat. An approximately 6-month-old crossbred goat was presented with a history of diarrhea for 1 week and death. The liver had grossly visible, coalescing foci of necrosis measuring up to 6 cm in greatest dimension. Microscopically, areas of coagulative necrosis also had ectatic and hyperplastic bile ducts that contained coccidial meronts, macrogamonts, and microgamonts within the cytoplasm of epithelial cells. Bile duct lumina contained scattered oocysts. Fibrosis and aggregates of lymphocytes surrounded affected ducts. Microscopic and ultrastructural characteristics of coccidian stages were compatible with the genus Eimeria, but the species could not be determined. The small intestine also had coccidios])L however, it was unclear whether or not the same coccidian species affected both the liver and the intestine.
An Immunohistochemical Study of Three Equine Pulmonary Granular Cell Tumors
Authors: Bouchard P. R. , Fortna C. H. , Rowland P. H. , Lewis R. M.
Published: January 2010

Granular cell tumor (GCT) is a morphologic designation for tumors of varied histogenesis. Most GCTs in human beings are derived from Schwann cells, and rat meningeal GCTs are believed to originate in the neural crest. Three equine pulmonary GCTs from aged horses were studied immunohistochemically with primary antibodies directed against vimentin, cytokeratins (AE1/AE3), S-100, Leu 7, desmin, and neuron-specific enolase (NSE) using a steptavidin–biotin procedure. All three tumors stained similarly with strong and diffuse staining of neoplastic cells for vimentin and S-100 and negative staining with all other antibodies. On the basis of the immunohistochemical results and the previously described histologic and ultrastructural characteristics, equine pulmonary GCT is designated as neural crest and possibly Schwann cell derived, similar to GCT in rats and human beings.
Epizootic Disseminated Toxoplasmosis in Captive Slender-tailed Meerkats (Suricata suricatta)
Authors: Juan-Sallés C. , Prats N. , López S. , Domingo M. , Marco A. J. , Morán J. F.
Published: January 2010

Fatal disseminated toxoplasmosis was diagnosed in seven captive slender-tailed meerkats ( Suricata suricatta) according to clinicopathologic findings and immunohistochemistry. Five of nine meerkats died during an outbreak in late 1994. These included four kits (2.5 to 4.5 months old) and a 4-year-old meerkat. Two other meerkats, both adults, died in 1992 and 1995. Respiratory insufficiency (4/7) and incoordination (3/7) were the most consistent clinical signs, although two of seven meerkats died unexpectedly. At necropsy, the lungs were reddened and noncollapsed (6/7), and had multiple pale round foci (4/7). Yellow foci of necrosis in mesenteric lymph nodes (4/7), splenomegaly (3/7), and hydropericardium (3/7) were other common gross findings. Microscopically, interstitial pneumonia was present in all seven meerkats, being acute to subacute in six of them. Type 2 pneumocyte hyperplasia, aggregates of foamy macrophages, and giant cells were consistently seen. Multifocal to locally extensive necrosis of mesenteric lymph nodes (4/7), mild to severe multifocal necrotizing hepatitis (5/6), and mild nonsuppurative encephalitis (4/6) were also seen. Toxoplasma-like organisms were consistently associated with these lesions and were stained by the avidin biotin peroxidase procedure with an antiserum that does not cross-react with Neospora caninum. Meerkats were most likely infected after an oral, primary exposure to Toxoplasma. Several observations indicate that meerkats may be highly susceptible to toxoplasmosis.
Multiple Pigmented Cutaneous Papules Associated with a Novel Canine Papillomavirus in an Immunosuppressed Dog
Authors: Le Net J.-L. , Orth G. , Sundberg J. P. , Cassonnet P. , Poisson L. , Masson M.-T. , George C. , Longeart L.
Published: January 2010

Cutaneous papillomavirus infection was diagnosed in a 6-year-old female Boxer dog that was under long-term corticosteroid therapy for atopic dermatitis. Multiple black, rounded papules were present on the ventral skin. Spontaneous regression occurred within 3 weeks after cessation of corticosteroids. Histologically, the lesions consisted of well-demarcated cup-shaped foci of epidermal endophytic hyperplasia with marked parakeratosis. In the upper stratum spinosum and in the stratum granulosum, solitary or small collections of enlarged keratinocytes were observed with basophilic intranuclear inclusion bodies and a single eosinophilic fibrillar cytoplasmic inclusion. Ultrastructurally, viruslike particles (40-45 nm in diameter) were observed within the nucleus, free or aggregated in crystalline arrays. Undulating fibrillar material, thought to be a modified keratin protein, was observed in the cytoplasmic inclusion. Immunohistochemistry, restriction enzyme analysis, and molecular hybridization experiments indicated that these distinctive clinical, histologic, and cytologic features were associated with a novel canine papillomavirus.
Fatal Infections with Balamuthia mandrillaris (a Free-living Amoeba) in Gorillas and Other Old World Primates
Authors: Rideout B. A. , Gardiner C. H. , Stalis I. H. , Zuba J. R. , Hadfield T. , Visvesvara G. S.
Published: January 2010

Balamuthia mandrillaris is a newly described free-living amoeba capable of causing fatal meningoencephalitis in humans and animals. Because the number of human cases is rapidly increasing, this infection is now considered an important emerging disease by the medical community. A retrospective review of the pathology database for the Zoological Society of San Diego (the San Diego Zoo and San Diego Wild Animal Park) for the period July 1965 through December 1994 revealed five cases of amoebic meningoencephalitis, all in Old World primates. The infected animals were a 3-year, 10-month-old female mandrill ( Papio sphinx), from which the original isolation of B. mandrillaris was made, a 5-year-old male white-cheeked gibbon ( Hylobates concolor leucogenys), a 1-year-old female western lowland gorilla ( Gorilla gorilla gorilla), a 13-year, 5-month-old male western lowland gorilla, and a 6-year-old female Kikuyu colobus monkey ( Colobus guereza kikuyuensis). Two different disease patterns were identified: the gibbon, mandrill, and 1-year-old gorilla had an acute to subacute necrotizing amoebic meningoencephalitis with a short clinical course, and the adult gorilla and colobus monkey had a granulomatous amoebic meningoencephalitis with extraneural fibrogranulomatous inflammatory lesions and a long clinical course. Indirect immunofluorescent staining of amoebas in brain sections with a Balamuthia-specific polyclonal antibody was positive in all five animals. Indirect immunofluorescent staining for several species of Acanthamoeba, Naegleria fowlel, and Hartmanella vermiformis was negative. Direct examination of water and soil samples from the gorilla and former mandrill enclosures revealed unidentified amoebas in 11/27 samples, but intraperitoneal inoculations in mice failed to induce disease. Attempts to isolate amoebas from frozen tissues from the adult male gorilla were unsuccessful.
The Equine Endometrial Mast Cell during the Puerperal Period: Evaluation of Mast Cell Numbers and Types in Comparison to Other Inflammatory Changes
Authors: Welle M. M. , Audigé L. , Belz J.-P.
Published: January 2010

Endometrial biopsies of 44 broodmares were histologically examined on days 3, 6, and 9 postpartum. The mares were subdivided into three groups according to the course of the puerperal period. In 29 mares, parturition and expulsion of the placenta was normal, six mares showed dystocia, and in nine mares, the placenta was retained for >2 hours. Tissue samples were evaluated histologically, and the average numbers of granulocytes, lymphocytes, macrophages, siderophages, and mast cells was determined. Protease content of mast cells was examined with a double-enzyme immunohistochemical staining technique, using a histochemical reaction for chloroacetate esterase and fast blue to detect chymase activity and an immunohistochemical staining method with a polyclonal antibody and fast red for the detection of tryptase. Analyzing the cell numbers using the statistical software Statistica, a marked inflammatory reaction was observed in the endometrium postpartum. Although the number of granulocytes decreased during the first 9 days postpartum, the number of lymphocytes, macrophages, and siderophages increased. No significant difference in the number of any of these cell types could be demonstrated in the three different courses of the puerperal period, although the numbers of these cells seemed to be lower in mares with dystocia. In contrast with other cells, no change in the number of endometrial mast cells was observed during the puerperal period, but a significantly lower number were found in the endometrium of mares with retained placenta. The enzyme immunohistochemical double-labeling technique could demonstrate only tryptase-positive mast cells; no chymase activity was detectable in any endometrial mast cells. The number of mast cells detected with the metachromatic staining technique was significantly higher than that detected with double labeling. These results support the hypothesis that a sufficient number of mast cells may be necessary for a normal postnatal period and suggest a mast cell subtype in the equine endometrium that is tryptase and chymase negative.
Cutaneous Malignant Melanomas in 57 Cats: Identification of (Amelanotic) Signet-ring and Balloon Cell Types and Verification of Their Origin by Immunohistochemistry, Electron Microscopy, and In Situ Hybridization
Authors: van der Linde-Sipman J. S. , de Wit M. M. L. , van Garderen E. , Molenbeek R. F. , van der Velde-Zimmermann D. , de Weger R. A.
Published: January 2010

Cutancous malignant melanomas in cats, both melanotic and amelanotic, were diagnosed in 57 of 1,530 skin tumors during the period 1991-1995. All melanomas occurred in domestic shorthaircats of ages 3-19 years ( $X = 11.5 years). Postmortem examination was performed on 16 cats. All had metastases in the regional lymph node and several organ systems. The average time of survival after surgical removal of the tumor was 4.5 months. Histologically, five types of melanomas could be distinguished: epithelioid, spindle, mixed, signet-ring, and balloon cell. Whereas all epithelioid, spindle, and mixed epithelioid/spindle cell types showed pigmentation, signet-ring and balloon cell types were often amelanotic. Immunohistochemical examination of the melanomas revealed a positive staining for S-100, vimentin, and neuron-specific enolase. The melanomas were negative for muscle cell markers, except in some of the signet-ring cell melanomas; 13 of 21 tumors showed a weak positive staining for polyclonal desmin. Electron microscopic examination of signet-ring cell melanomas revealed an abundance of intermediate filaments, whereas in some of these tumors a few cells with melanosomes were found. Nonisotopic in situ hybridization for mRNA encoding for tyrosinase verified the melanocytic origin of the amelanotic signet-ring and balloon cell melanomas.
Temporal and Morphologic Characterization of the Distribution of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) by In Situ Hybridization in Pigs Infected with Isolates of PRRSV that Differ in Virulence
Authors: Haynes J. S. , Halbur P. G. , Sirinarumitr T. , Paul P. S. , Meng X.-J. , Huffman E. L.
Published: January 2010

Three groups of 5-week-old cesarian-derived, colostrum-deprived pigs were inoculated intranasally with either a high-virulence isolate (VR2385) or a low-virulence isolate (VR2431) of porcine reproductive and respiratory syndrome virus (PRRSV) or with uninfected cell culture and media. Formalin-fixed, paraffin-embedded tissues from pigs euthanatized at 10, 21, and 28 days post-inoculation were examined by in situ hybridization for PRRSV nucleic acid using a digoxigenin-labeled antisense RNA probe approximately 1,000 nucleotides in length. Alveolar macrophages were positive in the lungs of 9/9, 2/2, and 0/2 VR2385-inoculated pigs and 7/9, 1/2, and 2/3 VR2431-inoculated pigs at 10, 21, and 28 days post-inoculation, respectively. More positive cells were detected in lungs from VR2385-inoculated pigs compared to VR2431-inoculated pigs at 10 and 21 days post-inoculation. Positive cells within lymph nodes were tingible body macrophages in germinal centers and macrophages or interdigitating dendritic cells within the paracortical areas. VR2385 was detected in the tracheobronchial lymph node (TBLN) and mediastinal lymph node (MLN) of 7/9 and 9/9 pigs at 10 days post-inoculation, but was only detected in the TBLN of 1/2 and 0/2 pigs and in the MLN of 0/2 and 1/2 pigs at 21 and 28 days post-inoculation, respectively. In contrast, VR2431 was detected in the TBLN and MLN of 5/9 and 2/9 pigs at 10 days post-inoculation and in the TBLN of 0/2 and 1/3 pigs and in the MLN of 0/2 and 0/3 pigs at 21 and 28 days post-inoculation, respectively. There were more positive cells in TBLN and MLN in pigs inoculated with VR2385 at 10 days post-inoculation. Macrophages located at the epitheliallymphoid interface of tonsilar crypts and within the paracortical areas were positive in tonsils of 9/9, 2/2, and 1/2 VR2385-inoculated pigs and 7/9, 1/2, and 1/3 VR2431-inoculated pigs at 10, 21, and 28 days post-inoculation, respectively. Positive cells in the thymic medulla were multinucleate and were only detected at 10 days post-inoculation in 2/9 VR2385-inoculated pigs and 4/9 VR2431-inoculated pigs. Positive cells within the spleen were few, spindle-shaped, located within smooth muscle trabecula, and only present at 10 days post-inoculation in 3/9 VR2385-inoculated pigs. We conclude that the tissue tropism and distribution of positive cells within tissues is similar for VR2385 and VR2431. However, tissues from more pigs and more cells within tissues were positive in pigs inoculated with VR2385 than VR2431 at 10 and 21 days post-inoculation. These findings indicate that the more virulent isolate VR2385 may replicate better in vivo than the less virulent isolate VR2431. This supports the hypothesis that an increased ability to replicate in vivo contributes to increased virulence of PRRSV.
Naturally Occurring Herpes Simplex Encephalitis in a Domestic Rabbit (Oryctolagus cuniculus)
Authors: Weissenböck H. , Hainfellner J. A. , Berger J. , Kasper I. , Budka H.
Published: January 2010

An approximately 1-year-old domestic rabbit showed severe neurologic signs with circling and turning somersaults. Histologically, a nonsuppurative meningoencephalitis with neuronal cell necrosis and numerous intranuclear inclusion bodies in neurons and glial cells was found. Electron microscopic examination revealed herpesvirus particles in affected cells. A human herpes simplex virus was identified by means of immunocytochemistry and in situ hybridization as the causal agent and was further classified as herpes simplex virus 1 by polymerase chain reaction analysis. Because encephalitis is easily induced in rabbits by experimental infection with herpes simplex virus, the source of infection is suspected to be a human with herpes labialis who had close contact with the rabbit.
T-cell-rich B-cell Lymphoma in a Cat
Authors: Steele K. E. , Saunders G. K. , Coleman G. D.
Published: January 2010

T-cell-rich B-cell lymphoma is a neoplasm recognized in humans in which a neoplastic proliferation of large B lymphocytes is present amid a background of reactive T lymphocytes. A 13-year-old Domestic Shorthair cat developed a mass in the region of the left parotid gland. Histologically, the mass was composed of scattered large atypical cells within a dense background of uniform small lymphoid cells. Immunohisto-chemically, the large cells were uniformly labeled using antiserum directed against the B-lymphocyte marker BLA.36, whereas labeling of nearly all of the small cells was limited to the T-lymphocyte marker CD3. The histomorphologic and immunohistochemical features of this unique feline neoplasm are characteristic of T-cell-rich B-cell lymphoma of humans.
Gastric Ulcer Associated with a Helicobacter-like Organism in a Cougar (Felis concolor)
Authors: Hill J. E. , Khanolkar S. S. , Stadtländer C. T. K.-H.
Published: January 2010

A 12-year-old captive female cougar ( Felis concolor) died following perforation of a gastric ulcer. Histologically, erosions and ulcers were present in the antral area of the stomach. Fibroplasia and infiltrates of neutrophils bordered the ulcers. Modified Steiner silver stain revealed numerous tightly coiled helical bacteria. The bacteria stained positively with a rabbit polyclonal anti- Helicobacter pylori antibody. Morphology, location, and positive immunohistochemical staining suggests that the organism is a Helicobacter.
Immunohistochemical Demonstration of Equine Herpesvirus-1 Antigen in Neurons and Astrocytes of Horses with Acute Paralysis
Authors: Schultheiss P. C. , Collins J. K. , Hotaling S. F.
Published: January 2010

Equine herpesvirus-1 (EHV-1) infection in a few widely scattered neurons and astrocytes plus endothelial cells in brain and spinal cord of two horses with naturally occurring paralytic disease was demonstrated by use of an immunoperoxidase technique. These horses were euthanatized less than 48 hours after the onset of clinical signs. No staining for EHV-1 was demonstrated in brain or spinal cord of three horses that had a longer duration of clinical disease or in two uninfected horses.
Exocrine Pancreatic Insufficiency in a Yellow-naped Amazon (Amazona ochrocephala) with Pancreatic Adenocarcinoma
Authors: Ritchey J. W. , Degernes L. A. , Brown T. T.
Published: January 2010

This report describes exocrine pancreatic insufficiency in a yellow-naped Amazon ( Amazona ochrocephala) with complete effacement of the pancreas by a pancreatic adenocarcinoma. The bird presented with a 3-month history of weight loss and voluminous, foul-smelling droppings. Clinically, routine hematologic findings were normal and fecal tests were performed to evaluate exocrine pancreatic function. The fecal function tests were positive for neutral and split fats and negative for trypsin. Oral administration of corn oil did not result in elevation of blood triglyceride levels. Two days later, the triglyceride tolerance test was repeated using corn oil mixed with pancreatic enzymes. This time, there was a 70% elevation of blood triglyceride levels. Because of a poor prognosis, the bird was euthanatized. At necropsy, the pancreas was diffusely enlarged, white, nodular, and firm. The liver contained multiple, 1-2-mm-diameter, randomly located, tan nodules. Microscopically, the pancreas was effaced by numerous lobules of neoplastic ductular structures surrounded by abundant fibrous connective tissue. In the liver, the hepatic parenchyma was replaced by multiple, well-demarcated, nonencapsulated foci of neoplastic tissue similar to that in the pancreas.
Ovarian Steroid Cell Tumor Resembling Luteoma Associated with Hyperadrenocorticism (Cushing's Disease) in a Dog
Authors: Yamini B. , VanDenBrink P. L. , Refsal K. R.
Published: January 2010

An ovarian steroid cell tumor was diagnosed in a 6.5-year-old female Rottweiler. The animal was polydipsic and polyuric, with an enlarged, pot-bellied abdomen. Radiographs and ultrasound examinations revealed an approximately 13-cm-diameter cystic mass below the right kidney. A low-dose dexamethasone suppression test was consistent with hyperadrenocorticism. Surgical exploration revealed an enlarged, lobulated left ovary approximately 10 cm in diameter, weighing 550 gs. Histologically, the ovarian tumor consisted of dense sheets and nests of round to polyhedral cells with abundant, finely vesiculated cytoplasm. The overall features were most consistent with ovarian steroid cell tumor resembling luteoma and associated with hyperadrenocorticism.
Cell Adhesion Molecules—Update
Authors: Elangbam C. S. , Qualls C. W. , Dahlgren R. R.
Published: January 2010

Cell adhesion molecules are glycoproteins expressed on the cell surface and play an important role in inflammatory as well as neoplastic diseases. There are four main groups: the integrin family, the immunoglobulin superfamily, selectins, and cadherins. The integrin family has eight subfamilies, designated as β1, through β8. The most widely studied subfamilies are β1 (CD29, very late activation [VLA] members), β2 (leukocyte integrins such as CDlla/CD18, CDllb/CD18, CDllc/CD18, and αdβ2), β3 (CD61, eytoadhesions), and β7 (α4β7 and αEβ7). The immunoglobulin superfamily includes leukocyte function antigen-2 (LFA-2 or CD2), leukocyte function antigen-3 (LFA-3 or CD58), intercellular adhesion molecules (ICAMs), vascular adhesion molecule-1 (VCAM-1), platelet-endothelial cell adhesion molecule-1 (PE-CAM-1), and mucosal addressin cell adhesion molecule-1 (MAdCAM-1). The selectin family includes E-selectin (CD62E), P-selectin (CD62P), and L-selectin (CD62L). Cadherins are major cell-cell adhesion molecules and include epithelial (E), placental (P), and neural (N) subclasses. The binding sites (ligands/receptors) are different for each of these cell adhesion molecules (e.g., ICAM binds to CD11/CD18; VCAM-1 binds to VLA-4). The specific cell adhesion molecules and their ligands that may be involved in pathologic conditions and potential therapeutie strategies by modulating the expression of these molecules will be discussed.
Morphologic, Immunohistochemical, and Ultrastructural Characterization of a Distinctive Renal Lesion in Dogs Putatively Associated withBorrelia burgdorferiInfection: 49 Cases (1987-1992)
Authors: Dambach D. M. , Smith C. A. , Lewis R. M. , Van Winkle T. J.
Published: January 2010

A distinctive renal lesion consisting of glomerulonephritis, diffuse tubular necrosis with regeneration, and interstitial inflammation was found in 49 biopsy/necropsy cases obtained from 1987 to 1992. This lesion is manifested clinically as a rapidly progressive glomerular disease that was uniformily fatal. Immunemediated membranoproliferative glomerulonephritis predominated (43/49, 88%). Membranous glomerulonephritis (5/49, 10%) and amyloidosis (1/49, 2%) were also noted. Subendothelial deposits, IgG, IgM, and C3 were present along glomerular basement membranes. IgA was absent. The exact cause of the tubular necrosis is unknown. Affected dogs were significantly younger (5.6 ± 2.6 years) than dogs with other forms of glomerulonephritis (7.1 ± 3.6 years) and amyloidosis (7.8 ± 3.5 years) both in the studied population for the same period and in the reported canine population. Labrador and Golden retrievers were 6.4 and 4.9 times more likely, respectively, to develop this lesion. This is the first report of a breed predilection for spontaneous canine glomerulonephritis. Previous reports have associated this lesion with Borrelia burgdorferi exposure. All dogs in this study were from Lyme disease-endemic areas. Of 18 dogs serologically tested, all were positive for exposure. Silver stain examination of kidneys revealed rare spirochetes, suggesting that the presence of spirochetes in the kidney is apparently unrelated to lesion development. The role of vaccination in development of the renal lesion is undetermined. The association of this histologically and clinically unique lesion, Lyme nephritis, with Borrelia burgdorferi infection is significant because it is the only fatal form of canine Lyme borreliosis.
African Swine Fever Virus Infection of Bone Marrow: Lesions and Pathogenesis
Authors: Gómez-Villamandos J. C. , Bautista M. J. , Carrasco L. , Caballero M. J. , Hervás J. , Villeda C. J. , Wilkinson P. J. , Sierra M. A.
Published: January 2010

The effects of African swine fever (ASF) virus infection on bone marrow hematopoiesis and microenvironment were determined by studying the sequential development of ultrastructural lesions of bone marrow and blood cell changes. Eight pigs (two pigs/infected group) were inoculated by intramuscular route with 10550% hemadsorbing doses (HAD50) of the Malawi'83 ASF virus isolate. Two uninfected pigs were used as controls. Ultrastructural changes developed by day 3 postinoculation (PI), persisted through day 7 PI, and were characterized by activation of macrophages. From day 5 PI, viral replication was observed in monocytes/macrophages, reticular cells, immature neutrophils, and promonocytes. Also viral replication was detected in megakaryocytes, endothelial cells, and pericytes at day 7 PI. Vascular alterations consisted of activation of sinusoidal endothelial cells, intravascular coagulation, and fibrin strands interspersed among microenvironment and hematopoietic cells. No significant changes were observed in total white blood cells counts, percentage of monocytes, and platelet counts; however, severe lymphopenia and neutrophilia were detected from day 3 PI. Results of this experiment indicate that there is increased hematopoiesis in bone marrow during acute ASF, coinciding with macrophage activation. Neither vascular changes nor viral replication in different bone marrow cell populations gave rise to impaired bone marrow function. Increased hematopoiesis would exert a positive influence by preventing the early onset of thrombocytopenia and would exert a negative influence by stimulating the spread of the virus via neutrophils. Increased hematopoiesis would be unable to compensate for the lymphopenia.
Phenotypic Characterization of Lymphocyte Subpopulations in Horses Affected with Chronic Obstructive Pulmonary Disease and in Normal Controls
Authors: Watson J. L. , Stott J. L. , Blanchard M. T. , Lavoie J.-P. , Wilson W. D. , Gershwin L. J. , Wilson D. W.
Published: January 2010

The alterations in lymphocyte subsets in chronic obstructive pulmonary disease (COPD) in the horse were investigated by using monoclonal antibodies to identify CD3+, CD4+, CD8+, and surface immunoglobulin positive (sIg+) lymphocytes in peripheral blood, bronchoalveolar lavage fluid (BALF), and pulmonary biopsy frozen tissue sections. COPD-affected horses ( n = 5) and normal controls ( n = 5) were sampled prestabling and 14 days poststabling, at which time the COPD-affected horses were exhibiting clinical signs of COPD. The peripheral blood absolute CD4+ lymphocyte count was significantly elevated in the COPD-affected horses pre- and poststabling. The CD4: CD8 ratio in peripheral blood of COPD-affected horses was unaffected by stabling, but the same ratio in the control horses was significantly decreased. These findings support a hypothesis of deficient regulation of a systemic immune response to indoor air in the COPD-affected horses. A large population of leukocytes in pulmonary biopsy immunohistochemical sections from both groups of horses appeared to be CD3+ CD4- CD8-, an uncommon phenotype in both the peripheral blood and BALF.
Autosomal Dominant Polycystic Kidney Disease in Persian and Persian-cross Cats
Authors: Eaton K. A. , Biller D. S. , DiBartola S. P. , Radin M. J. , Wellman M. L.
Published: January 2010

A form of autosomal dominant polycystic kidney disease (ADPKD) similar in clinical features to human ADPKD occurs in the Persian cat. We characterized the morphologic and immunohistochemical features of this disease in a colony of affected cats. Complete postmortem examinations were performed on 11 normal and 22 affected cats ranging in age from 3 months to 10 years. Kidneys were evaluated by gross and histologic examination, ultrastructure, lectin staining, bromodeoxyuridine immunochemistry for labeling index, and immunochemistry for distribution of Na/K ATPase. Feline ADPKD was characterized by variable numbers of cysts in the renal cortex and medulla. Ultrastructural examination and lectin staining suggested that cysts arose from proximal and distal nephron segments. Bromodeoxyuridine labeling demonstrated increased proliferation of epithelium lining some cysts in young cats. Immunohistochemical staining showed variable translocation of Na/K ATPase from the basolateral membranes of cyst-lining cells to the cytoplasm or luminal membranes. Cystic renal disease commonly was associated with chronic tubulointerstitial nephritis and hepatobiliary hyperplasia and fibrosis. Focal hyperplasia of renal tubular epithelium, hepatic cysts, and cardiac lesions were present in some cats. Feline ADPKD shares many morphologic and pathogenetic features with human ADPKD.
Tissue Tropism of the HPRS-103 Strain of J Subgroup Avian Leukosis Virus and of a Derivative Acutely Transforming Virus
Authors: Arshad S. S. , Howes K. , Barron G. S. , Smith L. M. , Russell P. H. , Payne L. N.
Published: January 2010

The tissue tropism was studied for the HPRS-103 strain of avian leukosis virus, which belongs to a new envelope subgroup, designated J. Studies were conducted in blood monocyte and bone marrow cell cultures and in chickens from six lines that had been shown previously to differ in susceptibility to induction by this virus of myeloid leukosis and other tumors. Using an immunohistochemical technique to detect expression of viral group-specific antigen (Gag) in various tissues, we detected no major differences among the six lines of chickens at 3 and 7 weeks of age following infection as embryos. Thus, Gag expression did not correlate with differences in tumor susceptibility. Of the tissues examined, greatest Gag expression was observed in cells specific to the adrenal gland, heart, kidney, and proventriculus and especially in smooth muscle cells and connective tissue. After infection of 1-day-old chicks, greater tissue expression was observed in line 21 chicks, which mostly developed a tolerant viremic infection, than in Brown Leghorn chicks, which developed virus-neutralizing antibodies. An acutely transforming virus, strain 966, derived from HPRS-103-induced myeloid leukosis, showed a tropism similar to HPRS-103. The HPRS-103 strain showed a lower propensity to replicate in the medullary region of the lymphoid follicles of the bursa of Fabricius than did the RAV-1 strain of subgroup A avian leukosis virus. This low bursal tropism may be a factor in why HPRS-103 does not induce lymphoid leukosis. The HPRS-103 and 966 virus replicated in blood monocyte cultures from chickens from the six lines, indicating a tropism for the myelomonocytic cell lineage. In comparison, as previously reported, RAV-1 did not replicate well in the monocyte cultures, whereas RAV-2, a subgroup B avian leukosis virus, did replicate. The tropism of HPRS-103 for monocytes may relate to its ability to cause myeloid leukosis. Monocyte and bone marrow cell cultures from the six lines ranked similarly in differences in susceptibility to transformation by 966 virus and showed evidence that their relative susceptibilities correlated with susceptibility of chickens from these lines to induction of myeloid leukosis by HPRS-103, suggesting common tissue-specific viral and host factors involved in oncogenesis by these two viruses.
Canine Neuroendocrine Tumors of the Pancreas: A Study Using Image Analysis Techniques for the Discrimination of Metastatic Versus Nonmetastatic Tumors
Authors: Minkus G. , Jütting U. , Aubele M. , Rodenacker K. , Gais P. , Breuer W. , Hermanns W.
Published: January 2010

Canine pancreatic neuroendocrine tumors were studied using different image analysis techniques (nuclear image histometry, analysis of argyrophilic proteins of nucleolar organizer regions, determination of the mouse anti-Ki 67 antigen proliferation index, and DNA densitometry) to correlate their biological behavior with objective phenotypic markers. The methods were compared to determine the best method for distinguishing between metastatic and nonmetastatic tumors. Discrimination between the two types of tumor was possible using nuclear image histometry in combination with morphometric analysis of argyrophilic proteins of nucleolar organizer regions. In contrast, the mouse anti-Ki 67 antigen proliferation index, DNA measurement, and immunohistochemical parameters revealed no significant difference between the two types of tumors.
Spontaneous Malignant Craniopharyngioma in an Albino Rat
Authors: Pace V. , Heider K. , Persohn E. , Schaetti P.
Published: January 2010

Craniopharyngioma is a rare neoplasm in the rat, and few cases have been described. These lesions are thought to originate from squamous cell remnants of Rathke's pouch, an evagination of primitive stomatodeum. This neoplasm is usually locally invasive, and neither cranial nor extracranial metastases have been described. A spontaneously occurring malignant, metastasizing craniopharyngioma arising from the neurohypophysis was detected in a 2-year-old male albino rat. The infiltrative growth was observed in the wall of the vessels of the circle of Willis, in the perivascular space of Virchow and Robin, in the submeningeal space near the hypothalamus, through the fissura chorioidea, in the medulla oblongata, and along the optic nerve into the periocular region. Metastases were detected in the thalamus and hippocampus. The diagnosis was made on the basis of microscopic, immunocytochemical, and ultrastructural findings.
Histochemical and Ultrastructural Characterization of Primary Cardiac Chondrosarcoma
Authors: Albers T. M. , Alroy J. , Garrod L. A. , Brown D. , Penninck D.
Published: January 2010

A cardiac chondrosarcoma was found in the right atrium of a Golden Retriever dog. Macroscopically, the right atrial lumen was filled with a 6- X 12- X 8-mm white glossy mass, which was diffusely attached to the underling myocardium. The mass was composed of spindle-shaped mesenchymal neoplastic cells loosely packed in light basophilic matrix, with focal areas of tightly packed cells in linear formation similar to the pattern of a growth plate. Tumor cells were positive when stained for vimentin and neuron-specific enolase, and weakly positive for S-100 protein. Ultrastructurally, neoplastic cells had abundant, dilated rough endoplasmic reticulum, Golgi apparatus, bundles of intermediate fibers, and primitive intercellular junctions between adjacent tumor cells. Based on morphologic, ultrastructural, histochemical, and immunohistochemical characteristics, this tumor was diagnosed as a chondrosarcoma.
Intracellular Campylobacter-like Organisms Associated with Rectal Prolapse and Proliferative Enteroproctitis in Emus (Dromaius novaehollandiae)
Authors: Lemarchand T. X. , Tully T. N. , Shane S. M. , Duncan D. E.
Published: January 2010

Rectal prolapse was the presenting clinical finding in a group of juvenile emus ( Dromaius novaehollandiae). Gross findings included severely thickened and rugose distal rectal mucosae. Histologically, there were thickened villi, enterocyte hyperplasia, dilated glands filled with mucus and heterophils, and a dense infiltrate of heterophils, macrophages, lymphocytes, and plasma cells in the lamina propria. Examination of Warthin-Starry silver-stained sections revealed numerous apically located comma-shaped intracytoplasmic bacteria approximately 1X3 μm in size. Campylobacter-like organisms morphologically compatible with ileal symbiont intracellularis now known as Lawsonia intracellularis were seen via electron microscopy. Bacteria were further characterized by indirect immunofluorescence using a monoclonal antibody specific for the 25-27-kd outer membrane protein of L. intracellularis.
Perforin-like Immunoreactivity in Four Cases of Lymphoma of Large Granular Lymphocytes in the Cat
Authors: Kariya K. , Konno A. , Ishida T.
Published: January 2010

Tumors composed of discrete round cells with large eosinophilic granules in their cytoplasm were observed in four cats. These cats were presented with severe gastrointestinal signs, including anorexia, vomiting, and diarrhea. The exploratory laparotomy in two cats and necropsy in the other two revealed thickening and perforation of the intestinal walls, enlargement of the mesenteric, ileocolic, and/or colic lymph nodes, and splenomegaly. Histologically, there was severe and disseminated infiltration of the tumor cells in the affected organs. In the two cats necropsied, the spleen and the jejunal mucosa appeared to be the primary organs involved. The tumor cells of all the cats showed the pore-forming protein (perforin)-like immunoreactivity unique to the cytotoxic lymphocytes but failed to show histamine immunoreactivity. These results indicate that the tumor cells were derived from large granular lymphocytes and that perforinlike immunoreactivity may be a useful marker for histologic diagnosis of feline large granular lymphoma.
Acute Arsenic Toxicosis in Five Horses
Authors: Pace L. W. , Turnquist S. E. , Casteel S. W. , Johnson P. J. , Frankeny R. L.
Published: January 2010

Five adult horses presented with acute clinical signs of watery diarrhea, excessive salivation, muscle tremors, ataxia, and depression. Four died within 24 hours and the fifth was euthanatized approximately 48 hours after onset of clinical signs. Necropsy findings in two of the horses included hyperemia of gastric mucosa, intestines filled with green to black watery fluid, and multifocal to coalescing, hemorrhagic 1.0-2.0-cm-diameter ulcers of the mucosa of the cecum and large colon. Histopathologic changes in the cecum and large colon consisted of mucosal necrosis and ulceration, vascular thrombosis, necrosis of submucosal blood vessels, and infiltration by mixed mononuclear inflammatory cells and neutrophils. Arsenic toxicosis was suspected. The owner had not been feeding the horses any grain; however, a mixture of grain and pink powder was found in the pasture. Liver arsenic concentrations in the two horses were 14.0 and 11.0 ppm, a sample of renal cortex contained 108 ppm arsenic, and the grain/powder mixture found in the pasture was positive for arsenic at <3,000 ppm. Kidney lead concentrations were 6.5 and 4.2 ppm. Results were consistent with lead arsenate or lead arsenite poisoning.
Ductuloendocrine Cell Proliferation in the Pancreas of Two Young Dogs with Diabetes Mellitus
Authors: Minkus G. , Breuer W. , Arun S. , Kirsch M. , Müller D. , Mueller J. , Hermanns W.
Published: January 2010

Two cases of diabetes mellitus in juvenile dogs (a 3-4-month-old Golden Retriever and a 2-month-old Labrador Retriever) are described here in terms of their clinical, histologic, and immunohistologic findings. Only very few insulin-positive cells were demonstrated immunohistochemically in one dog. In the second dog, the alterations of the pancreas consisted of hydropic vacuolar degeneration of B cells in the islets of Langerhans. In both cases, hyperplasia of the vacuolated cells was prominent. These cells formed tubular structures and were immunohistochemically positive for cytokeratin and proliferating cell antigen (MIB-1). Furthermore, within these vacuolated areas, some cells were positive to varying degrees for insulin, glucagon, somatostatin, and pancreatic polypeptide. Apoptotic cells could be seen in the exocrine pancreas, in vacuolated areas, and occasionally in the islets of both dogs. We interpret these alterations as ductuloendocrine cell proliferation, probably as an idiopathic compensatory response.
Immunohistochemical Identification of Porcine Respiratory Coronavirus Antigen in the Lung of Conventional Pigs
Authors: Ahn K. , Chae C. , Kweon C.-H.
Published: January 2010

Nine 3-week-old conventional pigs were inoculated intranasally with a Korean isolate of porcine respiratory coronavirus (PRCV). Three 3-week-old conventional pigs were kept as noninoculated controls. Three inoculated and one control pig were euthanatized at 5, 10, and 15 days postinoculation (DPI), respectively. All nine inoculated pigs developed respiratory disease. Interstitial pneumonia characterized by mononuclear inflammatory cell infiltration into alveolar septa were seen microscopically in all nine PRCV-infected pigs. Histopathologic changes were severe at 5 DPI, modest at 10 DPI, and almost resolved at 15 DPI. PRCV antigen was not detected in bronchial and bronchiolar epithelium but was detected in interstitial macrophages in the lungs. This Korean isolate of PRCV appeared to replicate primarily within alveolar macrophages in the respiratory system of the pig.
Angora Mouse Mutation: Altered Hair Cycle, Follicular Dystrophy, Phenotypic Maintenance of Skin Grafts, and Changes in Keratin Expression
Authors: Sundberg J. P. , Rourk M. H. , Boggess D. , Hogan M. E. , Sundberg B. A. , Bertolino A. P.
Published: January 2010

Angora is an autosomal recessive mouse mutation caused by a deletion of ∼2 kilobases in the fibroblast growth factor 5 ( Fgf5) gene. Phenotypically, homozygous angora ( Fgf5go/ Fgf5go) mice have excessively long truncal hair and can be differentiated from heterozygous (+/ Fgf5go) and wild-type (+/+) littermates by 21 days of age. Abnormal hair length is due to a prolongation of the anagen phase of the hair cycle of approximately 3 days. In addition, widely scattered hair follicles produce structurally defective hair shafts that twist within the follicle, presumably causing secondary hyperplasia of the outer root sheath and epidermis adjacent to the follicle. These follicular abnormalities were accentuated by immunohistochemical detection of mouse specific keratin 6, a nonspecific marker of epidermal hyperplasia. These abnormalities could be identified from birth throughout life in angora mice genotyped by polymerase chain reaction techniques. Moreover, the long truncal hair phenotype was maintained in skin grafted onto C.B-17/Sz- scid/scid mice that had normal pelage hairs and hair cycles, suggesting that circulating or diffusible humoral factors regulating the mouse hair cycle are not involved in this mutation. The angora mutation provides another useful mouse model for studying the hair cycle and its modulation.
Immunohistochemical Identification of Caprine Arthritis-Encephalitis Virus in Paraffin-embedded Specimens from Naturally Infected Goats
Authors: Storset A. K. , Evensen Ø. , Rimstad E.
Published: January 2010

The expression of caprine arthritis-encephalitis virus capsid protein was studied in seropositive naturally infected asymptomatic goats (10), seropositive naturally infected encephalitic kids (12) and goats (4), and noninfected control goats (3). Rabbit antiserum to recombinant viral capsid and matrix proteins were used in a biotin-streptavidin-alkaline phosphatase complex immunohistochemical method on sections of formalin-and ethanol-fixed tissue specimens. Macrophages in inflamed areas of the lung (8/12), in the brain (5/16), and in the spinal cord (4/16) from encephalitic animals harbored viral antigens, as revealed by immunohistochemistry and use of a capsid protein-specific antiserum. Altogether 12/16 encephalitic animals tested positive for viral antigen. Viral antigens were found in 5/10 seropositive asymptomatic goats in macrophages located in the lung (3), the udder (1), and the medulla of lymph nodes (4). None of the control animals tested positive for viral antigen. Ethanol fixation showed highest sensitivity, and the lowest antigen concentration that revealed a positive signal discernible from background was twofold higher in ethanol-fixed specimens than in formalin-fixed specimens. The evaluation was performed on artificial antigen substrates embedded with defined concentrations of recombinant viral capsid protein. Immunohistochemistry is a valuable supplement to the methods presently available for diagnosis in cases suspicious of caprine arthritis-encephalitis.
Encephalitozoon hellemin Budgerigars (Melopsittacus undulatus)
Authors: Black S. S. , Steinohrt L. A. , Bertucci D. C. , Rogers L. B. , Didier E. S.
Published: January 2010

Microsporidiosis with concurrent megabacteriosis in budgerigar ( Melopsittacus undulatus) chicks contributed to significant economic loss in a commercial pet bird aviary in Mississippi. Three budgerigar chicks, 1-2 weeks old, from the aviary were necropsied. Microscopic lesions in the chicks consisted of heavy infection of enterocytes with microsporidia (2/3; autolysis precluded critical evaluation of the intestine of chick No. 2), multifocal hepatic necrosis and inflammation with intralesional microsporidia (1/3), spherical clusters of microsporidia in the hepatic sinusoids in the absence of inflammation (1/3), and gastric megabacteriosis (3/3). The ultrastructure of the microsporidian spores was consistent with an Encephalitozoon species. The polymerase chain reaction and Southern blot analysis were used to identify the microsporidian as Encephalitozoon hellem, an organism that has only been identified in humans. Encephalitozoon hellem causes keratoconjunctivitis and respiratory infections in humans with acquired immunodeficiency syndrome. This report presents the first confirmed case of microsporidiosis in budgerigars. The finding of E. hellem in pet birds may be important in elucidating the epidemiology of human infections with this organism.