Morphology of Naturally-Occurring Tuberculosis in Cattle Caused by Mycobacterium caprae

This study describes the pathomorphological alterations of bovine tuberculosis through gross and histopathological examinations, assessment of the distribution of lesions and the demonstration of mycobacteria. Samples from lungs, liver, small intestine, their regional lymph nodes and retropharyngeal lymph nodes were collected from 84 cattle with tuberculosis from the Allgäu, Germany. Organs were evaluated grossly, histopathologically and by transmission electron microscopy. Mycobacteria and mycobacterial antigens were demonstrated using acid-fast staining and immunohistochemistry (IHC). Bacteriological tests revealed Mycobacterium caprae in all animals. Gross alterations were classified into five patterns (I to V) with an additional pattern of acute exudative pulmonary inflammation (pattern VI). Histological lesions were classified into four types (1-4) with additional lesions occurring in lungs only. Acid-fast staining revealed a low number of bacteria in all tissues, while IHC showed comparatively more mycobacterial antigens within the lesions and also at their periphery. The alimentary tract (68%) was the main portal of entry followed by an aerosol infection (19%). It was assumed that the observed lesions reflect a continuous primary period of infection; there were no lesions typical of a secondary (post-primary) period, as reported in man and also described in the older literature on bovine tuberculosis. The broad spectrum of changes described formerly was not observed in the present cases and the route of infection and nature of acid fast staining showed differences when compared with previous studies of naturally-occurring bovine tuberculosis.

Zinc Deficiency-Like Syndrome in Fleckvieh Calves: Clinical and Pathological Findings and Differentiation from Bovine Hereditary Zinc Deficiency

Background

Zinc deficiency‐like (ZDL) syndrome is an inherited defect of Fleckvieh calves, with striking similarity to bovine hereditary zinc deficiency (BHZD). However, the causative mutation in a phospholipase D4 encoding gene (PLD4) shows no connection to zinc metabolism.

Objectives

To describe clinical signs, laboratory variables, and pathological findings of ZDL syndrome and their utility to differentiate ZDL from BHZD and infectious diseases with similar phenotype.

Animals

Nine hospitalized calves with crusting dermatitis and confirmed mutation in PLD4 and medical records from 25 calves with crusting dermatitis or suspected zinc deficiency.

Methods

Prospective and retrospective case series.

Results

The 9 calves (age: 5–53 weeks) displayed a moderate to severe crusting dermatitis mainly on the head, ventrum, and joints. Respiratory and digestive tract inflammations were frequently observed. Zinc supplementation did not lead to remission of clinical signs in 4 calves. Laboratory variables revealed slight anemia in 8 calves, hypoalbuminemia in 6 calves, but reduced serum zinc concentrations in only 3 calves. Mucosal erosions/ulcerations were present in 7 calves and thymus atrophy or reduced thymic weights in 8 calves. Histologically, skin lesions were indistinguishable from BHZD. Retrospective analysis of medical records revealed the presence of this phenotype since 1988 and pedigree analysis revealed a common ancestor of several affected calves.

Conclusions and Clinical Importance

ZDL syndrome should be suspected in Fleckvieh calves with crusting dermatitis together with diarrhea or respiratory tract inflammations without response to oral zinc supplementation. Definite diagnosis requires molecular genetic confirmation of the PLD4 mutation.

Intersexualität beim Pferd – Pseudohermaphroditismus masculinus bei einer Bayerischen Warmblutstute

Bei einer sechsjährigen Bayerischen Warmblutstute konnte hengstartiges Verhalten beobachtet werden. Das äußere Erscheinungsbild der Geschlechtsorgane wies keine Auffälligkeiten auf. Das innere Genitale bestand aus einer blind endenden Vagina, die über ein strangartiges Gebilde mit intraabdominal liegenden Hoden in Verbindung stand. Der Testosteronwert des Pferdes lag im hengsttypischen Bereich. Durch eine zytogenetische Untersuchung konnte ein XY-Genotyp und mittels einer PCR das geschlechtsdeterminierende SRY-Gen nachgewiesen werden. Anhand dieser Befunde wurde ein Pseudohermaphroditismus masculinus diagnostiziert. Um die reiterliche Nutzung auch weiterhin zu gewährleisten, erfolgte eine bilaterale Gonadektomie via Flankenschnitt von der linken Seite.

Odontogene Tumoren bei Hund und Katze

Gegenstand und Ziel: Odontogene Tumoren kommen bei Hund und Katze, wie auch bei den übrigen Haustierarten und beim Menschen, selten vor und können schwer zu diagnostizieren sein. In der vorliegenden Studie wurde eine größere Anzahl odontogener Tumoren von Hund und Katze histopathologisch untersucht und klassifiziert mit dem Ziel, eine verlässliche Grundlage für die Diagnostik dieser Tumoren zu schaffen. Material und Methoden: In der retrospektiven Studie wurden von 1390 kaninen und 317 felinen oralen Tumoren aus den Jahren 1977 bis 2007 die odontogenen Neoplasien selektiert, histopathologisch charakterisiert und anhand der aktuellen human-und veterinärmedizinischen WHO-(World Health Organization) Klassifikationen odontogener Tumoren (2005 bzw. 2003) eingeteilt. Ergebnisse: 18% (n = 250) der kaninen und 3,2% (n = 10) der felinen oralen Tumoren erwiesen sich als odontogen. Sie ließen sich in benigne (epitheliale, epitheliale und ektomesenchymale sowie ektomesenchymale) und maligne odontogene Tumoren (Karzinome und Sarkome) mit insgesamt 12 Entitäten unterteilen. Sowohl beim Hund wie auch bei der Katze war das odontogene Fibrom der am häufigsten diagnostizierte Tumor (n = 167 bzw. n = 4). An zweiter Stelle folgte beim Hund das Ameloblastom (n = 74), bei der Katze das ameloblastische Fibrom (n = 2). Vier der 12 Entitäten konnten anhand beider, sieben lediglich anhand der human-, zwei lediglich anhand der veterinärmedizinischen WHO-Klassifikation klassifiziert werden. Schlussfolgerung und klinische Relevanz: Die prognostische Bewertung von Tumorerkrankungen ist von größter klinischer Relevanz und setzt eine eindeutige Diagnose voraus. Insbesondere bei seltenen und histomorphologisch komplexen odontogenen Tumoren genügt die aktuelle veterinärmedizinische WHO-Klassifikation diesem Anspruch nicht und bedarf einer Überarbeitung und Erweiterung. Wirkungsvoller im Einsatz erwies sich die humanmedizinische WHO-Klassifikation.

Untersuchungen zur ultraschallgeführten Lungenbiopsie beim Schwein

Ziel dieser Arbeit war eine Beurteilung der ultraschallgeführten Lungenbiopsie bezüglich ihrer Eignung zur Diagnostik von Pneumonien des Schweines. Ultraschalluntersuchungen und Biopsien der Lunge wurden in Allgemeinanästhesie bei insgesamt 60 Schweinen mit klinisch manifesten Lungenerkrankungen durchgeführt. Dabei handelte es sich um Tiere mit einem Körpergewicht zwischen 6 und 81 kg, die zur Diagnostik in die Tierklinik eingeliefert wurden. Das Risiko der Lungenbiopsie und die Folgen bis zu neun Tagen nach der Punktion wurden anhand klinischer, pulsoximetrischer und labordiagnostischer Untersuchungen der Tiere sowie sonographischer, pathologisch-anatomischer und histologischer Beurteilung der Biopsiestellen ermittelt. Eine Einschätzung des diagnostischen Wertes von Ultraschalluntersuchungen und Biopsie der Lunge erfolgte durch einen Vergleich der sonographischen und makroskopischen Lungenbefunde sowie durch vergleichende histologische und mikrobiologische Untersuchungen der Bioptate und des Lungengewebes post mortem. Risiken der Lungenbiopsie stellten die Narkose und Blutungen unmittelbar nach der Punktion dar. Im Verlauf der Anästhesie entwickelten 18% der Tiere eine lebensbedrohliche Dyspnoe. Mittel- bis hochgradige Blutungen traten bei 9,6% der punktierten Tiere auf. Als Risikofaktoren erwiesen sich Hämostasestörungen sowie ein geringes Körpergewicht. Pathologisch- anatomisch diagnostizierte pneumonische Verdichtungen wurden mit einer Sensitivität von 94% sonographisch erkannt und waren mit wenigen Ausnahmen hinsichtlich Art und Lokalisation der Veränderungen zu differenzieren. Als histologisch auswertbar erwiesen sich 78% der untersuchten Bioptate. Bei 43% der untersuchten, zu einem großen Teil antibiotisch vorbehandelten Tiere konnten aus den Lungenbioptaten ein oder zwei Keimarten nachgewiesen werden. Eine gute Übereinstimmung mit den Befunden des Sektionsmaterials bestand bezüglich der Häufigkeit isolierter lungenpathogener Keime. Unspezifische Keime waren häufig in den Sektionsproben nachweisbar, konnten dagegen aus keinem der Bioptate isoliert werden.

Validierung anamnestischer Angaben und ausgewählter klinischer Befunde im Hinblick auf Endokarditis beim Rind

Gegenstand und Ziel: Ziel dieser retrospektiven Arbeit war die Prüfung der diagnostischen Validität verschiedener anamnestischer Angaben und klinischer Befunde im Hinblick auf Endokarditis (EK). Material und Methoden: Zur Auswertung gelangten 958 Klinikkarten der Patienten der Klinik für Wiederkäuer aus den Jahren 1997–2004. Die Tiere wurden aufgrund ihres Herzbefundes, der sich aus der klinischen Untersuchung ergab (Herzgeräusch oder kein Herzgeräusch) und aufgrund des Sektionsbefundes (EK oder keine EK) in vier Gruppen eingeteilt. Ergebnisse: Zwischen den an EK erkrankten und nicht erkrankten Tieren bestanden signifikante Unterschiede hinsichtlich Ernährungszustand, Verhalten, Jugularvenen- und Herzbefunden. Außerdem litten EK-Patienten häufiger an Gliedmaßenproblemen. Schlussfolgerung und klinische Relevanz: Aus dem Vorbericht, den Ergebnissen der klinischen Untersuchung sowie den hämatologischen und klinisch-chemischen Befunden lässt sich der Verdacht auf eine Endokarditis zwar erhärten, aber die Sicherung der Diagnose ist nach wie vor in vielen Fällen der pathologischen Untersuchung vorbehalten.

Chronic Pancreatitis with Acinar-Ductal Metaplasia and Ductal Dysplasia in a Horse

A 16-year-old Friesian gelding with relapsing colic was humanely destroyed during diagnostic laparotomy due to suspected abdominal neoplasia. On post-mortem examination, the pancreas appeared as a firm mass (20 × 8 × 8 cm). The cut surface had a lobular structure with multiple cavities. Histological examination revealed severe chronic fibrosing pancreatitis with acinar-ductal metaplasia and duct dysplasia, which was considered to be the cause of the recurrent colic. Formation of tubular complexes within a background of acinar-ductal metaplasia is similar to the regressive lesions detected in the human pancreas in the context of inflammation, duct obstruction, cystic fibrosis and neoplasia. Pancreatic acinar-ductal metaplasia and ductal dysplasia are considered to be preneoplastic conditions in man and in the mouse.

Detection of monoclonality in intestinal lymphoma with polymerase chain reaction for antigen receptor gene rearrangement analysis to differentiate from enteritis in dogs

The diagnosis of canine intestinal lymphoma by morphological examination is challenging, especially when endoscopic tissue specimens are used. The utility of detection of antigen receptor gene rearrangement by polymerase chain reaction (PARR) in canine lymphoma has been well established, but its usefulness to distinguish enteritis and intestinal lymphoma remains unclear. In this retrospective study we assessed clonality of 29 primary canine intestinal lymphoma, 14 enteritis and 15 healthy control cases by PARR analysis, using formalin-fixed, paraffin-embedded full-thickness tissue specimens. We could detect monoclonal rearrangements in 22 of 29 canine intestinal lymphomas [76%; 95% confidence interval (CI) 56-90%] and polyclonal rearrangements in all of the enteritis and healthy control cases (100%; CI 88-100%). We revealed a predominance of T-cell phenotype compared to B-cell phenotype (85%; CI 65-96% and 15%; CI 4-35%, respectively). We showed that PARR analysis contributes to differentiation of canine intestinal lymphoma from enteritis and to phenotyping of lymphomas.

Naturally acquired bovine besnoitiosis: histological and immunohistochemical findings in acute, subacute, and chronic disease

The pathogenesis of bovine besnoitiosis, a disease of increasing concern within Europe, is still incompletely understood. In this study, disease progression after natural infection with the causative apicomplexan Besnoitia besnoiti was monitored in histological skin sections of 5 individual female cattle over time. High-frequency skin sampling of 2 cattle with mild and 2 with severe acute, subacute, and chronic besnoitiosis, as well as from 1 animal during subclinical disease, enabled documentation from the beginning of the disease. Skin sections were stained with hematoxylin and eosin and Giemsa, periodic acid-Schiff reaction, and anti-Besnoitia immunohistochemistry. In all 4 clinically affected animals, tachyzoite-like endozoites could be detected for the first time by immunohistochemistry, and tissue cyst evolution was monitored. Besnoitiosis-associated lesions were not detected in the animal showing the subclinical course. Because of the inconsistency of the nomenclature of Besnoitia tissue cyst layers in the literature, a new nomenclature for B. besnoiti cyst wall layers is proposed: tissue cysts consist of a hypertrophied host cell with enlarged nuclei, an intracytoplasmic parasitophorous vacuole with bradyzoites, a sometimes vacuolated inner cyst wall, and an outer cyst wall in more developed cysts. Inner and outer cyst walls can be readily distinguished by using special stains. In 1 animal, extracystic B. besnoiti zoites were immunohistochemically detected during the chronic stage. At necropsy, the 2 severely affected cows displayed large numbers of B. besnoiti cysts in a variety of tissues, including the corium of the claws, contributing mainly to the development of chronic laminitis in these 2 cases.

Endoscopically visualized lesions, histologic findings, and bacterial invasion in the gastrointestinal mucosa of dogs with acute hemorrhagic diarrhea syndrome

BACKGROUND

Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem.

OBJECTIVE

To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE.

ANIMALS

Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study.

METHODS

In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture.

RESULTS

Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term "HGE," which implies the involvement of the stomach, should be renamed as "acute hemorrhagic diarrhea syndrome."

Multiple Glucagon-Producing Pancreatic Neuroendocrine Tumors in a Horse (Equus caballus)

Pancreatic neuroendocrine tumors of glucagon-producing cells are extremely rare in domestic animals. In this report, we describe for the first time, to our knowledge, the incidental finding of multiple glucagon-producing neuroendocrine tumors of the pancreas of a horse. The animal was euthanized due to severe local infection after tooth extraction. On postmortem examination, multiple white nodules of up to 4 cm in diameter were observed in the pancreas. Histologically, pancreatic nodules had the appearance of neuroendocrine neoplasms with positive immunoreactivity for glucagon, synaptophysin, chromogranin A, and neuron-specific enolase. Electron microscopy revealed numerous electron-dense granules, similar to those observed in normal pancreatic alpha cells, in the neoplastic cells. In addition, the left adrenal gland showed multiple hyperplastic foci and adenomas in the medulla that were identified as pheochromocytomas. Based on the morphologic appearance and immunohistochemical staining pattern of pancreatic nodules, a diagnosis of multiple glucagon-producing neuroendocrine tumors was made.

[Odontogenic tumours in the dog and cat]

OBJECTIVE

Odontogenic tumours in the dog and cat, as well as in other domestic animals and in man occur rarely and can be difficult to diagnose. In the present study a great number of canine and feline odontogenic tumours were investigated histopathologically and classified to provide an appropriate basis for the evaluation of these tumours.

MATERIAL AND METHODS

In a retrospective study of a total of 1390 canine and 317 feline oral tumours from the years 1977 to 2007, the tumours of odontogenic origin were selected, characterized histopathologically and classified according to the current human WHO-classification of odontogenic tumours (2005) and the current veterinary WHO-classification of odontogenic tumours (2003).

RESULTS

18% (n=250) of the canine and 3.2% (n=10) of the feline oral tumours proved to be of odontogenic origin. They could be divided into benign (epithelial, epithelial and ectomesenchymal, ectomesenchymal) and malignant (carcinomas and sarcomas) odontogenic tumours with a total of 12 different entities. The odontogenic fibroma was the most common canine (n=167) and feline (n=4) odontogenic tumour. The second most common odontogenic tumour for canines was ameloblastoma (n=74) and that for felines was ameloblastic fibroma (n=2). Four of the 12 entities could be classified according to both WHO-classifications of odontogenic tumours. Seven and two of the 12 entities could only be classified according to the current human WHO-classification and veterinary WHO-classification, respectively.

CONCLUSION AND CLINICAL RELEVANCE

The prognostic evaluation of tumours is of the greatest clinical relevance and calls for an absolutely certain diagnosis. Particularly in the case of the rare and histomorphologically complex odontogenic tumours the current veterinary WHO-classification does not meet this requirement and needs to be revised and extended. The human WHO-classification proved to be more efficient when compared to the veterinary one.

Granulomatous pneumonia caused by Mycobacterium genavense in a dwarf rabbit (Oryctolagus cuniculus)

A juvenile dwarf rabbit (Oryctolagus cuniculus) with clinical signs of dyspnea and suspected ascites was submitted for necropsy. The main macroscopic findings were a watery red pleural effusion and some whitish striated foci in the lungs. In addition, there were multifocal scars in the cortex of the kidneys. The histologic examination of the lungs showed a severe granulomatous pneumonia with detection of acid-fast bacilli, in the kidneys, an interstitial chronic lymphoplasmacellular nephritis with interstitial fibrosis, and in the brain, a multifocal granulomatous and partly necrotizing encephalitis with detection of spores, suggestive of encephalitozoonosis. In the lungs, Mycobacterium genavense was verified by polymerase chain reaction and 16S ribosomal RNA gene sequencing. To our knowledge, this is the first report of an M. genavense infection in a rabbit, with the lungs being the only affected organ. Therefore, an aerogen infection seems to be the most contemplable way of infection.

First in vitro isolation of Besnoitia besnoiti from chronically infected cattle in Germany

Besnoitia besnoiti was in vitro isolated during the first recorded outbreak of bovine besnoitiosis in Germany. Molecular characterization of the new isolate, named Bb-GER1, revealed almost 100% identity with other B. besnoiti isolates obtained in Portugal, Spain, Israel or South Africa, when partial sequences of the 18S ribosomal RNA gene, of the internal transcribed spacer 1 and of the 5.8S RNA gene were compared. Cystozoites obtained from skin tissue of one bull were infectious for gamma-interferon knockout (GKO) mice by intraperitoneal (ip) inoculation. Tachyzoites were detected in the peritoneal cavity, spleen, liver and lung of the mice 5 days post-infection. The parasite could be maintained in GKO mice by ip inoculation for at least 5 passages. Peritoneal washings containing tachyzoites were obtained from infected mice and used to infect five cell lines (Vero, MARC-145, NA42/13, BHK(21), KH-R). The best growth of tachyzoites was observed in BHK(21) cells, but replication occurred to a smaller extent also in MARC-145, NA42/13 and KH-R cells. Subsequent comparative analyses revealed that after direct infection of these cell lines with cystozoites derived from bovine skin, the growth was best in NA42/13 cells. Considerable replication was also observed in the BHK(21) and KH-R cell lines. Our observations on the growth characteristics of Bb-GER1 partially contrast those for other isolates. The preferential growth in particular cell lines may be characteristic for particular B. besnoiti isolates. A potential association between growth properties and differences in virulence remains to be established. This is the first in vitro isolation of B. besnoiti from cattle in Germany.

Disseminated angiostrongylosis with fatal cerebral haemorrhages in two dogs in Germany: a clinical case study

Canine angiostrongylosis is a nematode infection in domestic dogs and wild carnivores. Few single case reports describing the occurrence of this disease in Germany exist and until recently angiostrongylosis has not been considered endemic in this country. The present report focuses on clinical, pathological and parasitological findings in two cases of fatal disseminated canine angiostrongylosis associated with multifocal haemorrhages in the central nervous system. Both animals, which lived in Germany, presented with rapidly progressive neurological signs including depression, ataxia, unilateral central blindness and epileptic seizures. Blood work revealed grossly elevated D-dimers and mild thrombocytopenia. Both animals were subsequently euthanised due to progressive clinical aggravation. Necropsy showed cerebral and lung haemorrhages in both animals. Multiple sections of nematode larvae consistent with Angiostrongylus vasorum were identified on histopathological sections of the brain, heart, kidney and lung in both animals and a predominantly granulomatous inflammation with the occurrence of multinucleated giant cells was observed. Adult nematodes were found in the larger lung arteries of one dog and Angiostrongylus infection was subsequently confirmed by PCR-analysis and sequencing in both dogs. A. vasorum larvae were not detected by faecal Baermann examination performed in one of the dogs. It was concluded that canine angiostrongylosis should be considered as differential diagnosis in dogs in Germany, even if faecal examination is negative. There is currently still a lack of studies investigating the occurrence of angiostrongylosis in dogs and intermediate hosts in Germany which would be necessary to survey the endemic realities of this disease.

Porzines Dermatitis-Nephropathie-Syndrom (PDNS) – eine Übersicht über pathomorphologische Veränderungen

Gegenstand und Ziel: Das porzine Dermatitis-Nephropathie- Syndrom (PDNS) wird in letzter Zeit immer häufiger beobachtet. Meist tritt es nur bei einzelnen oder wenigen Tieren eines Bestandes auf. Ziel dieser Studie war, typische pathomorphologische Befunde und die zeitliche Abfolge der Veränderungen darzustellen. Material und Methoden: Bei 22 Schweinen, die aus 16 verschiedenen Aufzucht- bzw. Mastbetrieben in Bayern stammten, wurde in den Jahren 2001 bis 2004 das porzine Dermatitis-Nephropathie-Syndrom (PDNS) klinisch sowie pathologisch-anatomisch diagnostiziert. Ergebnisse: Klinisch zeigten alle Tieren herdförmige, teils konfluierende Hautveränderungen mit tief reichenden Blutungen sowie multifokale Nekrosen mit krustösen Auflagerungen am gesamten Körper, insbesondere an den Hintergliedmaßen und dem Perineum. Charakteristischer pathomorphologischer Befund war eine hochgradige leukozytoklastische Vaskulitis der in Dermis und Subkutis gelegenen kleinkalibrigen Blutgefäße. In den Nieren fanden sich, neben einer akuten segmentalen nekrotisierenden Glomerulonephritis, chronische Veränderungen mit Verödung einzelner Glomerula sowie multifokale Synechien zwischen der Bowman‘schen Kapsel und den Glomerulumschlingen. Bei 21 Tieren wurde mithilfe der PCR das porzine Circovirus Typ 2 (PCV 2) und in fünf Fällen zusätzlich das Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) in der Lunge nachgewiesen. Schlussfolgerung: Trotz der typischen pathomorphologischen Befunde bleibt die Ätiologie des porzinen Dermatitis-Nephropathie-Syndroms bislang ungeklärt. Diskutiert werden sowohl virale als auch bakterielle Infektionen. Klinische Relevanz: Da die Frühform des PDNS klinisch nicht sicher von der akuten Verlaufsform der klassischen Schweinepest zu unterscheiden ist, kommt dem PDNS eine wichtige seuchenhygienische Bedeutung zu.

Klinische, hämatologische und klinisch-chemische Befunde beim porzinen Dermatitis-Nephropathie-Syndrom (PDNS)

Gegenstand und Ziel: Das porzine Dermatitis-Nephropathie- Syndrom (PDNS) wird erst seit wenigen Jahren beobachtet und ätiologisch mit einer porzinen Circovirus-Typ-2-Infektion (PCV-2) in Verbindung gebracht. Die Arbeit stellt klinische sowie labordiagnostische Befunde insbesondere zur Abgrenzung der klassischen Schweinepest dar. Material und Methoden: Bei insgesamt 46 Schweinen mit PDNS wurden klinische sowie hämatologische und klinisch-chemische Untersuchungen durchgeführt. Ergebnisse: Klinisch ließen sich petechiale bis flächenhafte Blutungen insbesondere im Bereich der Hintergliedmaßen und der Ohren feststellen. Die Inguinallymphknoten waren bei einem großen Anteil der untersuchten Tiere deutlich vergrößert. Die Leukozytenzahl sowie der Anteil an Lymphozyten lagen bis auf zwei Ausnahmen im Referenzbereich. Bei allen Tieren fanden sich eine Neutrophilie sowie deutlich erhöhte Harnstoff- und Kreatininwerte. Schlussfolgerungen: Klinisch ist das PDNS kaum von der klassischen Schweinepest zu unterscheiden. Anhand von hämatologischen und klinisch-chemischen Befunden lassen sich jedoch Unterschiede zur Schweinepest darstellen. Klinische Relevanz: Aufgrund des ähnlichen klinischen Bildes zur klassischen Schweinepest kommt dem PDNS auch eine seuchenrechtliche Bedeutung zu. Die Schweinepest sollte in jedem Fall durch geeignete Methoden ausgeschlossen werden.

Comparative morphologic and immunohistochemical investigation of spontaneously occurring thymomas in a colony of European hamsters

This study documents the characteristics of a large series of spontaneously occurring thymomas in a laboratory colony of European hamsters (Cricetus cricetus). Thymomas are rare organotypic neoplasms originating from the thymic epithelial compartment. Because the hamster thymomas largely resembled their human counterparts, the recent World Health Organization (WHO) classification of human thymic epithelial tumors was used. Forty hamsters of both sexes aged 3-29 months were examined macroscopically and histologically. In 22 (55%) of the 40 animals, necropsy revealed enormous whitish masses in the anterior mediastinum, with a diameter ranging from 0.5 to 4.5 cm and a lobulated structure. The anatomy of the thymus region was normal in the remaining 18 hamsters. Histologically, the tumors presented as thymuslike organoid structures with areas of medullary and cortical differentiation and a predominance of lymphoid cells. A network of epithelial cells in the cortical areas, demonstrated immunohistochemically with a cross-reactive antibody against pancytokeratin, supported the diagnosis of thymoma. Cortical lymphocytes showed positive staining with cross-reacting antibodies against CD3 and terminal deoxynucleotidyl transferase, characteristic of immature T cells. On the basis of these findings, the tumors were classified as B1 thymomas, in some cases with AB or B2 components, according to the new WHO classification for human thymic epithelial tumors.

[Endoscopic, pathologic-anatomic and histologic findings in the bovine teat. 2. Changes in the area of Fürstenberg's rosette]

In the present study endoscopically diagnosed changes of the Fürstenberg's rosette were examined histologically. For this purpose the teats of 200 slaughtered cows were inspected. In 19 cases proliferations in the region of the Fürstenberg's rosette were found. Additionally, tissue samples were taken from the Fürstenberg's rosette of 26 cows which showed milk flow disorders due to stenoses of this part of the teat. Teats of slaughtered cows as well as biopsy specimens were fixed in 5% formaldehyde and embedded in paraffin and in plastic. All specimens were stained according to H.E., Giemsa and Turnbull, respectively. Histologically, the proliferations of the Fürstenberg's rosette consisted of fibrovascular tissue (granulation tissue) covered by keratinized squamous epithelium (teat canal epithelium) in eleven cases. In the other cases double-layered cuboid epithelium (cisternal epithelium) was found additionally. The formation of granulation tissue and deposition of blood pigment was observed exclusively in areas covered by stratified epithelium. Therefore a traumatic lesion of the teat canal was supposed to be the cause of the histological findings. In contrast to several reports in the literature, however, no indications of an inversion of the teat canal epithelium were found. On the basis of these findings, the hitherto assumed idea of pathogenesis of proliferations of the Fürstenberg's rosette was modified and a new pathogenesis pattern was developed.

[Endoscopic, pathologic-anatomic and histologic findings in the bovine teat. 1. Changes in the area of the teat cistern in slaughtered cows]

In the present study 795 teats of slaughtered cows were examined endoscopically. Teats which showed lesions were examined histologically. Abnormalities were detected endoscopically in 37 teats. In five cases red discolorations were observed. Histologically these alterations proved to be fresh bleedings within the fibromuscular layer of the teat cistern. Thirteen teats showed yellowish discolorations of the cistern surface. Three of these cases could not be cleared up histologically. In the other cases moderate or severe blood pigment deposition (n = 10) or severe fibrosis (n = 3) of the fibromuscular layer were found. Neither fresh bleeding nor severe blood pigment deposition was found in teats with normal coloured epithelium of the cistern. Cistern surface was smooth in 18 cases, whereas in 19 cases nodules were found. Histologically all nodules consisted of fibrovascular tissue ("granulation tissue") covered with cisternal epithelium. Detailed histological examinations, however, revealed considerable morphological variations regarding the overlying epithelium, the extent and kind of cellular infiltration, the extent of angioplasia and fibroplasia as well as fresh bleedings or deposition of blood pigment in the underlying fibrovascular tissue in some cases. It was concluded, that teat endoscopy enables a differentiation between fresh and old bleedings according to the coloration of the cisternal surface. Nodular proliferations of the cistern surface generally consists of fibrovascular ("granulation") tissue. Further histological details, however, and thus possible information about the pathogenesis of the lesions cannot be assessed endoscopically.

Use of endoscopy and renal biopsy for the diagnosis of kidney disease in free-living birds of prey and owls

Eighty-nine free-living birds of prey and owls were examined and blood samples and radiographs were taken. In addition, 126 specimens of renal tissue were obtained without complications, with a mean postbiopsy haemorrhage time of 67 seconds. On average, the samples were 2.2 mm long, 1.3 mm wide and 1.0 mm deep and they all contained proximal and distal tubuli and from one to 89 glomeruli; 49 of them contained from one to four intralobular veins, and on average each sample contained 10.7 per cent air sac tissue; 113 of the 126 samples could be evaluated histologically.

[Enzootic calcinosis in sheep after consumption of golden oat grass (Trisetum flavescens L., P. B.)]

In 12 sheep (Coburger Fuchsschaf; 10 female, 1 male, 1 wether), grazing on a pasture with approximately 20 (to 40)% golden oat grass and fed the respective hay, clinical findings and outcome of Trisetum flavescens induced calcinosis were controlled for 2 1/2 years. Besides lameness typical for calcinosis (slightly bent carpus and relatively stretched position of tarsal and fetlock joints when standing, 'kneeling' on the carpi) the patients showed increasing impairment of the circulatory and respiratory systems (holosystolic endocardial murmur, congestion, exspiratory dyspnoea etc.). 4 of the 12 sheep died (2) or had to be euthanatized (2) because of peracute heart failure; 5 patients showing chronic circulatory insufficiency as well as 1 animal suffering from severe lameness had likewise to be euthanatized (Ubersicht 1-3). One calcinotic ewe (No. 12), still alive at the time of this evaluation (2003), gave birth to 2 healthy lambs and nursed them. The ram (No. 5) had to be eliminated for another disease. The mostly severe calcifications of the cardiac valves, the endocardium and the arterial vessels as observed during the pathomorphological examination are consistent with the clinically diagnosed cardiovascular insufficiency. Furthermore, calcification of several tendons and ligaments, the kidneys and in 3 cases of the pulmonary parenchyma could be found. Clinical observations and post mortem findings showed a remarkable individual variation. Compared to calcinosis in cattle, in sheep the functional disturbance of the circulatory system was striking.

Histopathologic and immunophenotypic characterization of extramedullary plasmacytomas in nine cats

To contribute to the existing body of knowledge in the literature on the apparently rare extramedullary plasmacytoma in cats, lymphoid tumors with plasmacytic cellular morphology taken from nine cats were examined. The paraffin-embedded material was investigated by standard hematoxylin and eosin, and special staining techniques (Giemsa, Congo-red, and periodic acid-Schiff reaction). The tumors also were examined immunohistochemically for the presence of immunoglobulin G, immunoglobulin A, immunoglobulin M, immunoglobulin light chains (lambda, kappa), various amyloid proteins, and FeLV-antigen (p27 protein). An immunoglobulin-producing tumor of plasmacellular origin (extramedullary plasmacytoma [EMP]) could be diagnosed in all cases on the basis of immunohistochemical light-chain expression. All but one of the neoplasms occurred in the skin of older, predominantly male cats. As in humans and dogs, the following types could be identified according to their morphologic features: mature type (two), cleaved type (two), asynchronous type (four), and polymorphous type (one). The tumor tissue of three cats revealed amyloid deposits, which were immunohistochemically diagnosed as ALlambda-amyloid in all three cases.

[Acute herpesvirus-gastritis in a cat]

Gastritis in cats is caused, among other things, by infectious agents, like bacteria, metazoic parasites or viruses. Herpesvirus-gastritis has not as yet been documented in cats. Therefore in this paper such a case will be described. In this case the mucous membrane of the stomach shows multifocal acute necroses with evidence of intranuclear inclusion bodies in epithelial cells of the gastric glands. By means of electron microscopy the causative virus can be specified as herpesvirus.

[Role of podocyte damage in the pathogenesis of glomerulosclerosis and tubulointerstitial lesions: findings in the growth hormone transgenic mouse model of progressive nephropathy]

The sequence of structural changes terminating in glomerulosclerosis, tubular atrophy and interstitial fibrosis was analyzed in the growth hormone (GH) transgenic mouse (TM) model of progressive renal disease. The investigation was performed in TM expressing the bovine GH gene under the control of the murine metallothionein-1-promoter and non-transgenic controls (CM) of different age groups. The kidneys were studied by light microscopy, transmission and scanning electron microscopy, and were analyzed with stereological methods. Early-stage renal lesions were characterized by glomerular hypertrophy and mesangial expansion. In 7-week-old TM the mean glomerular volume was twice that of age-matched CM. The number of endothelial and of mesangial cells per glomerulus was increased in TM vs. CM, while the number of podocytes did not change. The podocytes demonstrated hypertrophy and foot process effacement. Concomitant with an age-related further increase of glomerular size in TM, severe maladaptive podocyte lesions including detachment of podocytes were observed. The resultant denudation of the glomerular basement membrane was associated with severe proteinuria, glomerular hyalinosis, synechia formation and collapse of glomerular capillaries. These lesions progressed to glomerular obsolescence that was associated with atrophy of the adjacent tubule and interstitial fibrosis. The progressive kidney lesions in this model appear to be attributable to a considerable extent to podocyte damage resulting from the limited capacity of this cell type to keep up with progressing overall tuft growth. The findings provide further evidence that mature podocytes are unable for effective cell replication in vivo, and that podocyte damage plays a significant role in the pathogenesis of progressive glomerulosclerosis with tubular atrophy and interstitial fibrosis.

[Implantation of transponders at the bottom of the ear in equines]

In the present work transponders of 2 identification systems have been implanted on an exactly defined site at the bottom of the ear on 28 horses. The Backhome system is easier to handle and less complicated than the trovan system since it is smaller and handier. The hemorrhages that had occurred after the injection were mild at 17 animals and moderate at 4 animals. Inflame changes at the injection site post application were limited to minor swellings (n = 3) and minor pain (n = 6). The interrogator's scope of the two transponder systems is different. The interrogator's scope of the trovan transponder was approximate 5 to 10 cm and of the Backhome transponder approximate 15 to 25 cm resulting in a higher benefit. All 14 slaughtered horses were examined pathologically in different periods and two transponders were found to have changed their sites considerably at approximately 8 to 10 cm compared with the initial injection site. The connective tissue surrounding the transponder was transparent and thin in cases where the transponder had been implanted 30 days ago or earlier, histopathologically the tissue thickness changed. Inflammatory changes appeared in 3 cases as a minor perivasculitis and in further 5 cases as a collection of single siderophages. In the remaining 5 cases no inflammation was determined. The minor changes and lack of inflammation reflect the high biocompatibility of transponders.