bluuebunny/crossref_metadata_2025 huggingface dataset:
The Pathology of Spontaneously Occurring Malignant Lymphoma in Sheep
Authors: Johnstone A. C. , Manktelow B. W.
Published: January 2010

The most common locations of tumours in 22 sheep with malignant lymphoma were the lymph nodes (19 sheep), spleen (14), liver (13), kidney (10), small intestine (9) and heart (9). The distribution of the lesions could be classified as multicentric (14 sheep), alimentary (6), skin (1) and thymic (1).

Histological examination of malignant lymphomas from 40 sheep showed there were three reticulum cell sarcomas, and 37 lymphosarcomas.

The lymphosarcomas were further classified on the basis of cytological features as lymphoblastoid, lymphocytic/prolymphocytic, prolymphocytic and lymphocytic in 14, 6, 11 and six cases, respectively.

Viruses were not detected by electron microscopy in tumourous tissue from 10 sheep with malignant lymphoma.
Correlation of Microbiological and Histological Findings in Bovine Fibrinous Pneumonia
Authors: Schiefer B. , Ward G. E. , Moffatt R. E.
Published: January 2010

In a retrospective morphological and microbiological study, 39 of 55 cases of bovine fibrinous pneumonia were diagnosed as fibrinous pleuropneumonia. Twenty-nine of these 39 (74%) were associated with Pasteurella hemolytica, but only two cases (5%) with P. multocida. In contrast, of the 16 cases classified as fibrinous bronchopneumonia, one (6%) was associated with P. hemolytica, and nine (56%) with P. multocida.

In eight cases Mycoplasma and Hemophilus somnus were found in association with either P. hemolytica or P. multocida but were never isolated alone. We concluded that the use of the term pasteurellosis, implying Pasteurella as the cause, is imprecise because lesions associated with P. hemolytica fulfill the criteria of a fibrinous pleuropneumonia, whereas P. multocida is more likely to cause a bronchopneumonia with moderate amounts of fibrin.
Systemic Cartilage Defect in a Calf
Authors: Wild P. , Rowland A. C.
Published: January 2010

A 6-month-old Ayrshire calf had a systemic growth defect of cartilage. The most severe changes occurred in articular cartilage and epiphyseal plates of long bones where disturbance of ossification, necrosis, erosion, vascular invasion, proliferation of cartilaginous and fibrous tissue were seen. The lesions probably were the result of a failure in the initial phases of ossification and mechanical pressure was responsible for their severity in the cartilage of the limbs.
Leprosy in a Chimpanzee: Morphology of the Skin Lesions and Characterization of the Organism
Authors: Leininger J. R. , Donham K. J. , Rubino M. J.
Published: January 2010

Microscopic features of lepromatoid lesions in a chimpanzee inoculated with bovine leukemia virus consisted of diffuse dermal infiltrations of foamy histiocytes, except for a subepidermal “clear zone” devoid of infiltrating cells. Acid-fast organisms were in histiocytes, dermal nerves and a branch of the left radial nerve. The organisms were more intensely acid-fast with the Fite-Faraco than with the Ziehl-Neelsen stain. The organisms did not oxidize 3,4-dihydroxyphenylalanine (dopa) to indole but their acid-fast staining quality was removed by pretreatment with pyridine. Human leprosy patients, inoculated simultaneously with chimpanzee and human lepromin, reacted similarly to both lepromins. Organisms, when inoculated into mouse footpads, multiplied in 6 months to a quantity that was compatible with their identification as Mycobacterium leprae.
Effects of 4-Ipomeanol, a Product from Mold-Damaged Sweet Potatoes, on the Bovine Lung
Authors: Doster A. R. , Mitchell F. E. , Farrell R. L. , Wilson B. J.
Published: January 2010

Cattle given intraruminal administration of 4-ipomeanol, a furanoterpenoid originally obtained from sweet potatoes infected with Fusarium solani (F. javanicum), developed a respiratory syndrome clinically and histologically indistinguishable from atypical interstitial pneumonia. There were edema and emphysema in the lungs and mediastinum. The maximum nonlethal oral dose of 4-ipomeanol was estimated to be between 7.5 and 9 mg/kg of body weight.
Prevention of Avian Lymphoid Leukosis by Induction of Bursal Atrophy with Infectious Bursal Disease Viruses
Authors: Cheville N. F. , Okazaki W. , Lukert P. D. , Purchase H. G.
Published: January 2010

Five groups of genetically susceptible chickens were inoculated at hatching with lymphoid leukosis virus; four of these were given infectious bursal viruses of varying virulence at 14 days of age and one group was not inoculated (control). All chickens in the control group developed evidence of lymphoid leukosis by 180 days. Two groups given relatively virulent bursal disease viruses, which destroyed bursal lymphoid cells, did not develop lymphoid leukosis. Treatment with avirulent vaccines had no visible effect on bursal morphology and did not significantly alter the incidence of lymphoid leukosis in two other groups, although the lime of development was delayed. Results of our study show that viral-induced destruction of the bursa of Fabricius eliminates the development of lymphoid leukosis but that infection without bursal destruction has little effect on lymphoid leukosis.
Feline Panleukopenia: III. Development of Lesions in the Lymphoid Tissues
Authors: Carlson J. H. , Scott F. W. , Duncan J. R.
Published: January 2010

Germfree and specific pathogen-free cats were inoculated with feline panleukopenia virus. Cats were necropsied 2 to 6 days after inoculation and tissues from the thymus, lymph nodes and spleen taken for histological and immunofluorescence studies. Necrosis of lymphoid cells in the thymic cortex began 3 days after inoculation and continued for 5 to 6 days after inoculation when the thymus was nearly depleted of lymphocytes. Immunofluorescence studies showed the lesions to be caused by virus. There was gross and histological involution of the thymus in both germfree and specific pathogen-free cats. The lymph nodes and spleen of uninoculated germfree cats looked “inactive” and lacked well developed lymphoid follicles and paracortical areas. In both germfree and specific pathogenfree cats there was necrosis in both follicular and paracortical areas of the lymph nodes and follicular and paracortical areas of the spleen 3 to 4 days after inoculation. Immunofluorescence showed these areas had virus infection. By 5 to 6 days after inoculation, these areas were populated by many lymphoblastoid cells. Even though significant destruction of lymphoid cells occurred, subsequently, in cats that develop mild clinical illness, these lymphoid tissues seemed stimulated rather than depleted of lymphocytes.
Lethal Encephalitis in 14-Day-Old Mice Given Avirulent Semliki Forest Virus
Authors: Chew-Lim M.
Published: January 2010

Avirulent Semliki Forest Virus when inoculated intracerebrally and intraperitoneally into 14-day-old Swiss A2G mice induced a lethal encephalitis. There was destruction of neurones, especially pyramidal cells of the hippocampus, despite a rising serum antibody titer.
An Ultrastructural Study of Avian Synovium Infected With An Arthrotropic Mycoplasma, Mycoplasma synoviae
Authors: Walker E. R. , Friedman M. H. , Olson N. O. , Sahu S. P. , Mengoli H. F.
Published: January 2010

Live Mycoplasma synoviae cells in agar base medium were inoculated intravenously into 10 2-week-old chickens. Joint tissues were collected over a 3-week period for light and transmission electron microscopy. In infected chickens, membrane-bound vacuoles of intact M. synoviae cells were seen in the cytoplasm of adipose cells. Cytoplasmic lipid-containing inclusions had accumulated in enlarged fibroblasts in tendon sheaths and loose connective tissue. Synovial cells had proliferated and contained increased amounts of granular endoplasmic reticulum and lipid inclusions. No abnormalities were seen in control chickens. Infected chickens were positive and control chickens were negative for rheumatoid factor activity by two serological tests: tanned cell hemagglutination and latex agglutination tests.
Feline Myeloproliferative Disease. Changing Manifestations in the Peripheral Blood
Authors: Harvey J. W. , Shields R. P. , Gaskin J. M.
Published: January 2010

A 4 1/2-year-old cat had myeloproliferative disease characterized by severe anemia. Peripheral blood had a profusion of relatively normal-appearing nucleated erythroid cells in all stages of development and a few primitive cells with nucleoli. The term “erythremic myelosis” best described the appearance of the peripheral blood. Two weeks later, the peripheral blood picture was that of regenerative anemia. During the next 2 months the cat made an apparent clinical recovery without treatment, but relapsed 3 months after the initial examination. One-fourth of the cells in circulation at the time of relapse contained nucleoli and appeared identical to those described in reticuloendotheliosis in cats. This transition suggested the progressive development of a greater degree of immaturity of erythroid precursors with time. The use of the term “reticuloendotheliosis” in conjunction with feline myeloproliferative disease was considered and determined inappropriate.
Morphology of the “Sulphur Granules” (Drusen) in Some Actinomycotic Infections. A Light and Electron Microscopic Study
Authors: Bestetti G.
Published: January 2010

The granules (Drusen) within the inflammatory lesions in three cases of infection by Actinomyeetales were studied with light and electron microscopy. The material consisted of subcutaneous granulomas caused by Actinomyces bovis in a cow, epidural granulomas caused by A. viscosus in the spinal canal of a cat and cerebral granulomas caused by Nocardia in a dog.

The granules of A. bovis were 2000 to 3000 micrometers in diameter. Their centers consisted of a slightly basophilic, gram- and grocott-negative material with branching, gram-and grocott-positive filaments. The periphery was slightly basophilic or eosinophilic, but gram- and grocott-positive. Its surface was made of clubs (15 × 3.5 micrometers); they were acidophilic, gram- and grocott-negative. In the center of the granule there are numerous type a cells (coccobacillary cells with a trilaminar cell wall of 12 nanometers) and rarely type b cells (filaments with bilaminar cell wall of 30 nanometers). The periphery was made of germinative centers of type a cells. The clubs were lytic type b cells, embedded in an amorphous material.

The granules (Drusen) of A. viscosus were 200 to 600 micrometers in diameter. Their center was slightly eosinophilic, gram- and grocott-negative and contained gram- and grocott-positive filaments. Their periphery was basophilic and contained alternating gram-and grocott-negative areas and radial gram- and grocott-positive filaments. There were no clubs. In the center there were type b cells (filaments with a trilaminar cellular wall of 30 nanometers). The periphery was made of germinative centers of type a cells (coccobacillary with a trilaminar cell wall of 10 to 11 nanometers). The germinative centers were separated from each other by radial bundles of type b cells.

The granules (Drusen) of Nocardia were acidophilic, gram- and grocott-positive and surrounded by 1.8 × 0.5-micrometer clubs that were acidophilic, gram- and grocott-negative. There were type a cells (filamentous to bacillary with monolaminar cell wall of 19 nanometers and cross wall) and type b cells (filamentous to bacillary with monolaminar cell wall of 65 nanometers and without cross wall).

The remarkable morphological differences of the three species of Actinomycetales are specific, independent from host and type of tissue, and therefore reliable for diagnostic purposes.
Renal Oxalosis in Neonatal Calves
Authors: Gopal T. , Leipold H. W. , Cook J. E.
Published: January 2010

Kidney tissues were collected from 142 calves during a study of pre- and perinatal mortality. Fifty-six calves had oxalate crystals in their renal tissue. Thirty-four of the 56 had either single or multiple congenital defects, mostly of the skeleton. Twenty-two of the 56 died of causes other than congenital defects. The renal oxalosis was more pronounced in those calves affected with congenital anomalies.
Intracranial Teratoma in a Domestic Rabbit
Authors: Bishop L.
Published: January 2010

A solid and cystic suprasellar teratoma was found in a rabbit killed because of incoordination. The tumor consisted of neural cells, cysts lined by various types of epithelium, respiratory mucosa, gastric mucosa, mucous and mucoserous glands, collagenous connective tissue, cartilage and fat.
Clinicopathological Studies in Experimental Hypothyroidism in Goats
Authors: Sreekumaran T. , Rajan A.
Published: January 2010

Goats given thiourea had hypothyroidism in various degrees. There was reduction in weight gain and oedema of face and limbs. There was an increase in serum cholesterol which was highest in goats given the lowest dose of thiourea. Protein-bound iodine decreased sharply and there was an increase in plasma protein.
Canine Gastric Adenocarcinoma
Authors: Patnaik A. K. , Hurvitz A. I. , Johnson G. F.
Published: January 2010

In a retrospective study of 26 gastric adenocarcinomas of the dog, 17 were found to have histologic features of the diffuse type and nine of the intestinal type similar to those of the same tumor in man. The intestinal type was characterized by distinct glandular structures lined with well polarized cells at the primary and metastatic sites and mild desmoplastic reaction. Three subtypes with distinct histologic features (papillary, five; acinar, three; solid, one) were recognized in this group. Fourteen of the diffuse adenocarcinomas were characterized by random infiltration by neoplastic cells, singly or in clusters, often with signet ring cells and severe desmoplastic reaction. The remaining three diffuse adenocarcinomas also had recognizable acinar structures and were considered to be glandular subtypes of the diffuse type.

In eight dogs there was a 7:1 male to female ratio for dogs with the intestinal type and in 16 dogs a 2:1 male to female ratio for dogs with the diffuse type. Two of the nine intestinal type of adenocarcinomas, but none of the diffuse tumors, had intraluminal growths. Metaplasia of gastric epithelium was seen in nearly half the tumors; this was more common in the intestinal type (six of nine). Different degrees of carcinomatosis were seen in 24 of 26 dogs. Regional lymph nodes were involved in the 20 dogs whose nodes were available for examination. Distant metastases were seen in 19 of 26 dogs; liver, lungs and adrenal glands were the most common sites. Various degrees of lymphoid cell infiltration, suggesting the antigenic quality of the neoplasms, were seen in 15 dogs. Additional neoplasms were seen in eight dogs.
The Pathogenesis of Trypanosoma congolense Infection in Calves. I. Clinical Observations and Gross Pathological Changes
Authors: Valli V. E. O. , Forsberg C. M. , Robinson G. A.
Published: January 2010

Holstein calves infected with Trypanosoma congolense TREU 112 had intermittent fever, debility and a poor hair coat. At postmortem examination the most significant findings were enlargement of the liver, kidneys and spleen and increased volume of hematopoietic marrow. A group of 13 calves infected for 18 weeks had marked enlargement of lymph nodes throughout the body and hemal nodes were prominent in the sublumbar area caudal to the kidneys. Another group infected for 7 weeks had no increase in the weight of lymph nodes. Studies with 51Cr labelled autologous red cells given shortly before postmortem examination showed that the liver was the most active organ with respect to sequestration of labelled red cells.
Beiträge zum Lebenszyklus der Frenkelien. IV. Pathomorphologische Befunde an den Organen experimentell infizierter Rötelmäuse
Authors: Geisel O. , Kaiser E. , Krampitz H. E. , Rommel M.
Published: January 2010

In 1975 the buzzard ( Buteo buteo) was found to be the final host of Frenkelia clethrionomyobuteonis. After this discovery it became possible to investigate systematically the pathomorphology of the infection in the intermediate host, the bank vole ( Clethrionomys glareolus).

Fifty bank voles were infected orally with a suspension of sporocysts recovered from the faeces of experimentally infected buzzards. Each rodent received 7000 sporocysts. Six controls each were given a faecal suspension from a non-infected buzzard. The voles were killed between 1 and 140 days after infection and examined histologically.

Between the 5th and 8th day of the infection during the schizogonic multiplication of the parasite a focal necrosis of liver cells and of the liver parenchyma is observed followed by a reversible resorptive inflammation associated with siderophagia and the occurrence of giant cells. The spleen was spodogenously enlarged up to twice its normal size. There also was haemosiderosis of the bone marrow, the liver and the spleen up to 25 days after infection. At the same time the erythropoiesis in the bone marrow, the spleen and in the lymph nodes increased; there also was a lymphoid hyperplasia in spleen and lymph nodes. About 10 days after infection a reversible infiltration with lymphocytes and plasma cells developed in the liver, heart and brain. This infiltration was again detectable as perivascular and meningeal reactions in the brain after the 49th day after infection. The second asexual multiplication of the parasite was seen histologically in the grey and white matter of the central nervous system after the 18th day of infection. The developing cysts increased in size continuously thereby compressing the surrounding nervous tissue. Disseminated focal necrosis with resorptive inflammatory components was prominent in the parenchyma of the brain after the 49th day of infection.

It was possible to differentiate between damage in single organs and systemic pathological lesions. The lesions in single organs were directly connected with the development of parasitic stages in the liver (schizonts) and in the brain (cysts). The generalized lesions occurred in the haemopoietic system after an impairment of the blood during the first asexual multiplication. They also occurred in the immunocytic systems after the first and during the second asexual multiplication and during the relatively late cystic phase of the parasite in the brain. The pathogenesis of the disintegration of blood cells is not clear. The immunocytic reaction can be considered an immunological response of the host against the parasite. The effect of the development of the cysts on the function and structure of the central nervous system is expected to lead to an increasing impairment of the motility of the intermediate host.
A Freeze-Etching Study on Experimental Murine Mastitis
Authors: Smith K. , Chandler R. L.
Published: January 2010

Streptococcal mastitis was produced experimentally in mice inoculated by the intramammary route; freeze-etched preparations from the affected mammary glands were studied by electron microscopy. The inoculated cocci were seen free in the acinar lumen, within luminal phagocytes and within cells of the epithelium. No significant pathological changes were noted in the junctional complexes between secretory epithelial cells. The results were comparable to those obtained by ultrathin sectioning and indicated that, while cocci can transfer from the acinar lumen into the substance of the epithelium and towards a subepithelial location, the junctional complexes between epithelial cells present a potential barrier to movement through the intercellular spaces.
The Goitrogenic Effect of 4,4'-Oxydianiline in Rats and Mice
Authors: Hayden D. W. , Wade G. G. , Handler A. H.
Published: January 2010

Fischer 344 rats and B6C3F1 mice were fed diets that contained 0.03, 0.06, 0.1 and 0.2% 4,4'-oxydianiline for 13 weeks. The 0.1 to 0.2% diet caused 40 to 70% mortality in female rats. Although mice ate about 3.5 times more chemical than rats, no mice died. Alopecia, dyspnea and cyanosis in rats, and lethargy in both species occurred in the 0.1 to 0.2% groups. Goiter was found in rats that died as early as the 4th to 5th week of study in the groups given the 0.06 to 0.1% diet. At the end of the study, diffuse parenchymatous goiter was seen in all rats given the 0.06% and higher concentration diets and in most mice given the 0.2% diet. In rats, the thyroids also were heavily encapsulated and had interstitial fibrosis and vascular degeneration. There was concomitant hyperplasia of pituitary basophils in both species, but an increase of cells that secrete thyrotropin was seen in rats only.
Frequency of Canine and Feline Tumors in a Defined Population
Authors: MacVean D. W. , Monlux A. W. , Anderson P. S. , Silberg S. L. , Roszel J. F.
Published: January 2010

The Tulsa Registry of Canine and Feline Neoplasms was the second animal tumor registry in the United States concerned with a defined population in a delimited geographic area. Only tumors histologically confirmed by registry pathologists were included in frequency statistics based on the annual dog and cat population presented to veterinarians.

During the first registry year, about 1% of the 63,504 dogs and 0.5% of the 11,909 cats had one or more primary tumors. While the incidence rate for malignant tumors in dogs was similar to that in cats, the incidence of benign tumors of dogs was over 10 times that of cats. The most common tumors were sebaceous adenoma in dogs and lymphosarcoma in cats. Mammary cancer was the most common malignant tumor in dogs. Mammary tumors of female dogs were significantly more frequent in Pointers, Poodles and Boston Terriers, in that order, than in other breeds. A greater incidence of mammary tumors among intact compared to spayed female dogs was seen for virtually every age group except in the Pointer breed.
A Canine Cutaneous Lymphoproliferative Disease Resembling Mycosis Fungoides in Man
Authors: Shadduck J. A. , Reedy L. , Lawton G. , Freeman R.
Published: January 2010

A dog with a lymphoproliferative disease resembling mycosis fungoides in man, the second reported canine case, had slowly progressive, multicentric cutaneous nodules and plaques. Nearly half the body surface was involved. The lesions consisted of multiple, flat, infiltrative, cutaneous tumors composed of heterogeneous, pleomorphic cells, some of which resembled histiocytes or activated lymphocytes. Intracutaneous foci of tumor cells and numerous tumor cells with bizarre convoluted nuclei were distinctive features that permitted the lesions to be distinguished from other non-epithelial cutaneous neoplasms.
The Pathogenesis of Trypanosoma congolense Infection in Calves. II. Anemia and Erythroid Response
Authors: Valli V. E. O. , Forsberg C. M. , McSherry B. J.
Published: January 2010

The anemia caused by Trypanosoma conogolense TREU 112 in Holstein calves was of moderate severity and normochromic, macrocytic in the acute phase changing to normochromic, normocytic with chronicity. The anemia was hemolytic and responsive as shown by sharply decreased myeloid:erythroid ratio and increased mean corpuscular volume. 51Cr red cell labelling studies showed that red cell lifespan was halved in the acute phase and there was an increase in plasma volume. Surface organ counting of liver showed it to be the major site of red cell destruction. The anemia was partly dilutional as a result of the increased plasma volume and primarily hemolytic likely of a non-specific immune (innocent bystander) pathogenesis.
Effects of Anabolic Steroids on Liver Cell Ultrastructure in Sheep
Authors: Reid I. M. , Donaldson I. A. , Heitzman R. J.
Published: January 2010

Castrated male sheep were sham implanted or implanted with estradiol, trenbolone acetate or trenbolone acetate in combination with estradiol, and slaughtered after 56 days. Ultrastructural and morphometric examination of the livers of steroid-treated sheep showed an increase in the volume density of the cell occupied by rough endoplasmic reticulum and microbodies. In four of the eight sheep treated with trenbolone acetate, either alone or in combination with estradiol, enlarged mitochondria with crystalline inclusions were seen. The increase in hepatic rough endoplasmic reticulum may be of benefit to the sheep whereas the mitochondrial changes after anabolic steroid use indicate a cellular lesion of unknown significance for health.
Absence of Bacterial Adherence in the Establishment of Experimental Mastitis in Mice
Authors: Anderson J. C.
Published: January 2010

The possibility of adherence of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli or Streptococcus agalactiae to the epithelium of the mammary gland was investigated by inoculating them into this gland of mice. S. aureus, S. epidermidis and E. coli did not adhere to alveolar epithelium in suckling or non-suckling mice. S. agalactiae adhered to alveolar epithelium in non-suckling mice but adhesion was not sufficiently strong to withstand suckling. Bacterial adherence probably does not play a significant role in the establishment of mastitis by these organisms.
Lesions of Contagious Equine Metritis in Mares
Authors: Acland H. M. , Kenney R. M.
Published: January 2010

Twenty-three mares were infected with contagious equine metritis organism by intrauterine inoculation, and necropsied after intervals of two to 116 days. Severe diffuse subacute salpingitis was seen in one mare, and mild multifocal subacute salpingitis was common. Severe diffuse endometritis and cervicitis initially were acute and became more severe, subacute and predominantly plasmacytic by 14 days, then declined but persisted as mild diffuse or multifocal inflammation for the rest of the experimental period. Vaginitis arose in parallel but resolved after 70 days. There were no lesions in the clitoral fossa or clitoral sinus.
Respiratory Tract Lesions from Infectious Laryngotracheitis Virus of Low Virulence
Authors: Russell R. G.
Published: January 2010

The pathogenicity of the A4557-5 strain of infectious laryngotracheitis virus for eight-week-old chickens was investigated by acrosol route of infection; chickens were necropsied five days after infection. The virus caused mild catarrhal tracheitis, peribronchial lymphoid infiltration, and focal lymphocytic infiltration in the lung and focal lymphocytic infiltration in the air sacs of some chickens. Chickens infected with this virus developed low levels of humoral antibody and were resistant to intratracheal challenge with the virulent V154 strain. By comparison, aerosol infection with a similar dose of virulent V154 strain caused severe necrotizing laryngotracheitis with marked suppurative bronchopneumonia and airsacculitis.
Primary Ocular Melanoma in Dogs
Authors: Diters R. w. , Dubelzig R. R. , Aguirre G. D. , Acland G. M.
Published: January 2010

The clinical signs, gross and microscopic appearance, treatment, and follow-up results of 35 dogs with primary ocular melanomas are reviewed. The melanomas are classified as epibulbar or intraocular based on the site of origin. The intraocular tumors are classified as spindle A, spindle B, mixed spindle B and epithelioid, and purely epithelioid based on cytologic criteria. The pathologic findings are matched with the follow-up history in an attempt to determine which features have prognostic significance. The findings are contrasted to those of similar studies of spontaneous ocular melanomas in man.
Peliosis Hepatis-like Lesion in Aging Rats
Authors: Lee K. P.
Published: January 2010

The incidence of peliosis hepais-like lesions in two-year-old Charles River-CD Sprague-Dawley rats (Charles River Breeding laboratories, Wilmington, MA) was almost twice as high in males as females. Blood lakes developed from progressive expansion of sinusoids with destruction of the hepatic cell cords. The endothelial processes of the blood lakes had edematous swelling, vesiculation, and denudation. The microvilli of hepatocytes became swollen, blunted, and sloughed where the endothelial processes were disrupted. Subsequently, the hepatocytes were exposed directly to circulating blood cells and had degenerative changes with accumulation of red blood cells in the cytoplasm.

The membrane-bound cysts were observed with the blood lakes and were bounded with atrophic hepatocytes or membranous wall extending to the Disse's space of adjacent hepatocytes. The cysts were filled with proteinaccous fluid, fibrin, and a few red blood cells. The wall of membrane-bound cysts consisted of endothelial processes extending from the endothelial cells of adjacent hepatocytes. The wall appeared to develop from adhesion of endothelial processes surrounding sinusoidal spaces of the hepatocytes following lysis of atrophic hepatocytes.
Hemophilus somnusin the Reproductive Tracts of Slaughtered Cows: Location and Frequency of Isolations and Lesions
Authors: Miller R. B. , Barnum D. A. , McEntee K. E.
Published: January 2010

One hundred bovine female reproductive tracts were examined for the presence of Hemophilus somnus, and fifty were examined for gross and microscopic lesions. H. somnus was isolated from eight of 100 tracts. The isolation was made from the vagina in seven cows. Of 24 tracts in which the major vestibular gland was sampled, three were positive at this site, and two of these three also had the organism isolated from the vagina. Further investigations into the role of the major vestibular gland as a source for continuing infections of the reproductive tract of cattle were indicated. In this investigation. H. somnus was as likely to be found in a region without lesions as one with lesions.
The Effects of Intra-amniotic Inoculation ofHemophilus somnuson the Bovine Fetus and Dam
Authors: Miller R. B. , Van Camp S. D. , Barnum D. A.
Published: January 2010

The injection of three strains of Hemophilus somnus into the amniotic cavity of pregnant cows produced death of the fetus and abortion followed by retention of the placenta. H. somnus was recovered readily from the placenta but less so from the fetus. Lesions in the placenta were conspicuous in arteries and somewhat resembled vascular lesions observed in septicemic H. somnus. H. somnus was recovered from the maternal circulation in several infected cows. Clinical signs included fever, irritability, lameness, and vulvar discharge, but no cows died. The organism was recovered for prolonged periods in cervicovaginal mucus and urine after remission of clinical signs. This may be a means of spread of infection.
Light and Electron Microscopic Changes in Cardiac and Skeletal Muscle of Sheep with Experimental Monensin Toxicosis
Authors: Confer A. W. , Reavis D. U. , Panciera R. J.
Published: January 2010

Monensin toxicosis was induced in lambs by either a single oral dose of 12 mg/kg or six daily doses of 8 mg/kg. Clinical signs of toxicosis consisted of depression, dyspnea, stiffness of gait, reluctance to move, and recumbency. Serum creatine phosphokinase activity was increased. Samples of skeletal and cardiac muscle were obtained over a six-day period and examined by light and electron microscopy. Light microscopic changes in cardiac and skeletal muscles consisted initially of vacuolation and intracellular edema of muscle cells followed by segmental necrosis. Interstitial fibrosis was present on days 5 and 6 postexposure. Muscle fiber necrosis was more severe in skeletal than cardiac muscles and most severe in sheep given 8 mg/kg of monensin daily. Macrophages were seen only in areas of severe necrosis. The earliest ultrastructural change was severe swelling of mitochondria. Secondary changes consisted of lipid accumulation and myofibrillar alterations. Myoblast proliferation was present as early as four days after initial exposure to monensin.
The Toxicity of Aristolochia bracteata in Goats
Authors: Barakat S. E. M. , Wasfi I. A. , Adam S. E. I.
Published: January 2010

Diarrhea, dyspnea, tympany, arching of the back, loss of condition, and loss of hair from the back were the prominent signs when Aristolochia bracteata was given orally to goats. The main lesions were hemorrhages in the lungs, heart, and kidneys, fatty change and congestion in the liver, mucoid abomasitis and enteritis and straw-colored fluid in serous cavities. An increase in aspartate aminotransferase activity, ammonia and urea concentrations and a decrease in the concentrations of total protein and magnesium were detected in the serum.
Trabecular Bone Morphometry in Beagles with Hyperadrenocorticism and Adrenal Adenomas
Authors: Norrdin R. W. , Carpenter T. R. , Hamilton B. F. , Brewster R. D.
Published: January 2010

Trabecular bone morphometry was done on rib samples of beagles with hyperadrenocorticism and adrenal adenomas to evaluate bone loss and the remodeling changes responsible. Beagles diagnosed as having clinical hyperadrenocorticism and those with milder or subclinical hyperadrenocorticism diagnosed on the basis of adrenal and pituitary lesions at necropsy had increased adrenal and pituitary gland weights. In a group of dogs with adrenal cortical adenomas there was atrophy of remaining cortex, and the combined weight of adrenal glands or pituitary weights were not increased. In dogs with clinical hyperadrenocorticism, mean trabecular bone volume was 25% less than controls ( P = 0.10). In both clinical and subclinical hyperadrenocorticism groups, the extent of trabecular surface with unmineralized osteoid matrix and osteoblasts was significantly reduced. There were no changes in resorption surfaces or number of osteoclasts present. No bone changes were seen in dogs with adrenal adenomas. In dogs with hyperadrenocorticism it appeared that decreased bone formation was primarily responsible for the relative osteopenia that developed. Although parathyroid glands were moderately enlarged in those dogs for which weights were available, the bone changes were not those of increased remodeling expected in hyperparathyroidism.
GM1 Gangliosidosis in Portuguese Water Dogs: Pathologic and Biochemical Findings
Authors: Saunders G. K. , Wood P. A. , Myers R. K. , Shell L. G. , Carithers R.
Published: January 2010

Three Portuguese water dog siblings, all females aged 5 to 7 months, were killed following a brief period of neurologic disease. Tissues were processed for light and electron microscopy and for biochemical analyses. All pups had membranous cytoplasmic inclusions in neurons throughout the brain and spinal cord. Cytoplasmic vacuoles were present in cells of many organs outside the nervous system. GM1 ganglioside in brain was markedly elevated in all three dogs, and β-galactosidase activity was less than 10% of control values. These findings are similar to those in GM1 gangliosidosis of man and animals although the number of organs and tissues containing vacuolated cells is greater.
IgM-Mesangial Nephropathy in Callithricids
Authors: Brack M.
Published: January 2010

Spontaneous IgM-mediated mesangioproliferative nephropathy was detected in 91% of tamarins and marmosets over 6 months old. The disease remains silent for long periods but is progressive. It is responsible for, or is at least related to, the cause of death in 20% of animals. Morphological characteristics are those of mesangial hyperplasia accompanied by subacute to chronic interstitial inflammation. The immunopathological demonstration of early accumulation of IgM within the mesangial cells and matrix, followed by interstitial deposition of C3, suggests that the lesion is mediated by immunological mechanisms.
Pneumonia in Lambs Inoculated withBordetella parapertussis: Bronchoalveolar Lavage and Ultrastructural Studies
Authors: Chen W. , Alley M. R. , Manktelow B. W. , Hopcroft D. , Bennett R.
Published: January 2010

Eight colostrum-deprived lambs were inoculated intratracheally with ovine isolates of Bordetella parapertussis. Fluids obtained by bronchoalveolar lavage had a large increase in total cell counts 24 hours after inoculation; up to 93% of cells were neutrophils. From 3 days after inoculation, the number of alveolar macrophages in lavage samples was markedly increased. From 5 days onwards, many alveolar macrophages had moderate to severe cytoplasmic vacuolation. Topographically, tracheal and bronchial epithelium was covered by a large amount of inflammatory exudate 24 hours after inoculation. Later, the tracheobronchial epithelium showed focal extrusions from ciliated cells, which were occasionally associated with B. parapertussis organisms. Ultrastructurally, cytopathological changes associated with B. parapertussis infection were mild focal degeneration of airway epithelium with slight loss of cilia, moderate to severe degeneration of type I and type II alveolar epithelial cells, and focal inflammation in the lungs. These results suggest that the primary targets of B. parapertussis infection are alveolar macrophages and the epithelial cells of bronchioles and alveoli.
Morphologic and Immunohistochemical Characterization of the Hepatic Lesions Associated with European Brown Hare Syndrome
Authors: Gavier-Widén D.
Published: January 2010

Liver lesions were studied in 40 free-living adult European brown hares ( Lepus europaeus) and varying hares ( Lepus timidus) of both sexes that had died in Sweden with the viral infection European brown hare syndrome (EBHS). The lesions were characterized by their histopathologic, immunohistochemical, and electron microscopic findings. Periportal to massive coagulation necrosis was a distinctive feature of EBHS. Lytic necrosis, inflammation, fatty degeneration, and cholangitis occurred variably. Accumulation of basophilic granules in the cytoplasm of hepatocytes was commonly observed; these lesions corresponded ultrastructurally to mitochondrial calcification. Viral antigen was revealed in the cytoplasm and nucleus of hepatocytes and in the cytoplasm of macrophages.
Ocular Fibropapillomas of Green Turtles (Chelonia mydas)
Authors: Brooks D. E. , Ginn P. E. , Miller T. R. , Bramson L. , Jacobson E. R.
Published: January 2010

Histologic evaluation of four eyes from three stranded juvenile green turtles ( Chelonia mydas) from Florida, USA revealed ocular fibropapillomas composed of an overlying hyperplastic epithelium, various amounts of a thickened, well vascularized, collagenous stroma, and a moderate-to-dense population of reactive fibroblasts. The histologic morphology of the ocular fibropapillomas varied depending on whether the eyelid, conjunctiva, limbus, or cornea was the primary site of tumor origin. Fibropapillomas arising from the limbus, conjunctiva, or eyelid tended to be polyploid or pedunculated with a high degree of arborization. They often filled the conjunctival fornices and extended externally to be ulcerated on the distal aspects. Corneal fibropapillomas were more sessile and multinodular with less arborization. Some corneal tumors consisted primarily of a broad fibrovascular stroma and mild epithelial hyperplasia, whereas others had a markedly hyperplastic epithelium supported by stalks of fibrovascular stromal tissue. In green turtles ocular fibropapillomas may be locally invasive and associated with severe blindness and systemic debilitation.
Distribution of Anti-CD68 (EBM11) Immunoreactivity in Formalin-fixed, Paraffin-Embedded Bovine Tissues
Authors: Ackermann M. R. , DeBey B. M. , Stabel T. J. , Gold J. H. , Register K. B. , Meehan J. T.
Published: January 2010

A commercially acquired anti-human macrophage antibody (anti-CD68; EBM11) was used in an immunocytochemical technique to detect macrophages in formalin-fixed, paraffin-embedded tissues from cattle, pigs, humans, rats, turkeys, dogs, and cats. In healthy cattle, the antibody labeled alveolar macrophages, pulmonary intravascular cells (presumably intravascular macrophages), and macrophage-like cells in other tissues. In bovine lungs infected with Pasteurella haemolytica, EBM11 antibody labeled 95% of alveolar macrophages and macrophages within alveolar septa but only 0–2% of streaming or “oat” leukocytes. Alveolar macrophages were also stained by EBM11 in pigs but not in rats, turkeys, dogs, and cats. The antibody also stained macrophage aggregates in the mesenteric lymph nodes and intestinal lamina propria of Mycobacterium paratuberculosis-infected cattle. This study shows that the anti-CD68 (EBM11) antibody is a useful marker of macrophages in normal bovine tissues or tissues from areas of acute or chronic inflammation that have been routinely processed. The study also adds strength to the growing evidence suggesting that streaming leukocytes seen in pneumonic pasteurellosis are neutrophils.
A Sequential Study of the Light and Electron Microscopic Liver Lesions of Infectious Anemia in Atlantic Salmon (Salmo salar L.)
Authors: Speilberg L. , Evensen Ø. , Dannevig B. H.
Published: January 2010

The present study describes light and electron microscopic changes in the liver of Atlantic salmon during the development of infectious salmon anemia (ISA). Atlantic salmon postsmolts weighing 80-100 g were infected by intraperitoneal injections, and liver samples were collected sequentially between day 0 and day 25 post infection (p.i.), with time intervals of 3-4 days. At each collection time, livers from five infected fish and two control fish were examined. Changes involving the perisinusoidal macrophages were observed by transmission electron microscopy, from day 4 p.i. Large vacuoles, containing a fine-granular material with low electron density, accumulated in the cytoplasm. These changes persisted and became more severe throughout the investigation, leading to a considerable increase in the size of the cells. At day 14 p.i., degenerative features of the sinusoidal endothelium were observed. By day 18 p.i., areas of the liver were devoid of a sinusoidal endothelial lining, bringing hepatocytes in direct contact with blood cells. At this stage, the sinusoids were moderately congested. From day 21 p.i., heavy sinusoidal congestion, peliosis hepatis, and degeneration of the hepatocytes were observed. No virus was observed in any of the inhabitant cell types of the liver. Gross and light microscopic changes were first recorded at day 18 p.i., as was a significant decrease in the hematocrit values. By day 25 p.i., characteristic multifocal, confluent, hemorrhagic necroses were present. Results of the present investigation suggest that the liver lesions observed with ISA are not the result of the development of an anemia alone or caused by direct viral damage to hepatocytes. Hepatocellular degeneration succeeded changes in the perisinusoidal macrophages and degeneration of the sinusoidal endothelium. These changes may have impeded the sinusoidal blood flow and hence caused an ischemic hepatocellular necrosis.
Neuronal Ceroid-lipofuscinosis in a Cat
Authors: Bildfell R. , Matwichuk C. , Mitchell S. , Ward P.
Published: January 2010

Neuronal ceroid-lipofuscinosis was diagnosed in a young adult domestic short-haired cat euthanatized because of severe progressive neurologic disease. Clinical signs included blindness, seizures, and decreased mentation. An autofluorescent pigment, identified as ceroid-lipofuscin by electron microscopy and staining properties, was found within neurons of the central and peripheral nervous systems. A diffuse reactive astrocytosis accompanied by multifocal microgliosis was visible in all areas of the brain. Retinal atrophy with intraneuronal lipopigment accumulation was also identified. Contrary to the human neuronal ceroid-lipofuscinoses, pigment deposition appeared to be restricted to neural tissues.
Observations on Neonatal Mortality of the Chacoan Peccary, Catagonus wagneri
Authors: Benirschke K. , Hager D. A. , Edwards D. K.
Published: January 2010

The considerable neonatal mortality of a captive population of Chacoan peccaries, the taguá ( Catagonus wagneri), in Paraguay was investigated with the examination of six newborn animals and one adult. Most deaths occur primarily because of restriction of space resulting in competition for space and nutrition. The adult had nonlethal inhalation pulmonary anthracosis. Neonatal pulmonary nocardiosis was noted in one infant and is believed to be related to the dust storms prevailing locally. Another neonate had a duplication of the pelvis, rear extremities, and one ovary, representing a type of conjoined twin classified as ischiopagus.
Malignant Melanocytic Neural Crest Tumor in a Young Chicken (Gallus domesticus)
Authors: Hafner S. , Latimer K. , Kelley L. C. , Wortham K. , Puette M.
Published: January 2010

A malignant melanocytic tumor was found in an 8-week-old chicken. The tumor, which was composed of melanocytes, ganglion cells, nerves, and primitive pressure receptors, was examined by light microscopy, transmission electron microscopy, and immunohistochemistry. Antibodies to neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), and S-100 protein variably stained nerves, but melanocytes were only rarely immunolabelled by NSE antibodies and there was no specific staining of these cells for S-100 or GFAP. Ultrastructurally, neoplastic melanocytes contained melanin within melanosomes and premelanosomes and did not resemble Schwann cells.
Ocular Halicephalobus (syn. Micronema) deletrix in a Horse
Authors: Rames D. S. , Miller D. K. , Barthel R. , Craig T. M. , Dziezyc J. , Helman R. G. , Mealey R.
Published: January 2010

Ocular contents from a horse with a 4-week history of severe unilateral uveitis were submitted for histopathologic examination. A severe unilateral granulomatous chorioretinitis with intralesional Halicephalobus deletrix-was diagnosed. The horse developed progressive neurologic signs several days following the surgery to remove ocular contents and implant a prosthesis and was subsequently euthanatized. A severe multifocal granulomatous encephalitis with intralesional H. deletrix, localized primarily to the optic chiasm, thalamus, and brain stem, was diagnosed from tissues acquired at necropsy. The other eye was not affected. This is the first report of ocular parasitism by H. deletrix and suggests possible systemic dissemination from a primary site in the eye.
Primary Lung Neoplasia in a Beagle Colony
Authors: Hahn F. F. , Muggenburg B. A. , Griffith W. C.
Published: January 2010

As part of long-term pulmonary carcinogenesis studies in dogs, it is important to analyze the incidence of spontaneous lung neoplasia. Primary lung carcinoma incidence was determined in two control populations of Beagle dogs observed for their life spans. One population comprised 216 dogs (112 males and 104 females) that were controls for life span studies, and another comprised 182 dogs (50 males and 132 females) that were retirees from a breeding colony. Forty lung neoplasms were noted in the 398 dogs; 35 neoplasms were carcinomas classified as papillary adenocarcinoma (20), bronchioloalveolar carcinoma (9), adenosquamous carcinoma (5), or bronchial gland carcinoma (1). The other five neoplasms were a malignant fibrous histiocytoma, three adenomas, and a fibroma. The crude incidence of lung carcinomas averaged for both populations was 8.8% (35/398) and was dominated by a relatively high incidence of lung neoplasia in aged dogs, those dying after the median life span of 13.6 years.