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Introduction: Autoimmune diseases are of considerable importance in dog breeding. An increased risk of diseases with genetic predisposition is present especially in breeds with a limited genetic diversity. Strict breeding regulations and a high degree of self responsibility of the breeders are essential to prevent these diseases. There are only a few DNA tests available for detecting carriers of genes predisposing for autoimmune diseases. In this review, we describe the special situation in the Nova Scotia Duck Tolling Retriever, who has a special predisposition for Systemic Lupus Erythematosus (SLE) and for Immune-mediated Rheumatoid Disease (IMRD), as well as for Steroid-Responsive Meningitis Arteritis (SRMA) and Juvenile Addison's Disease (JADD). In addition a short overview on the pathogenesis of autoimmune disease is presented.

Introduction: A female jogger was attacked by a common buzzard (Buteo buteo) and was scratched lightly at the back of the head. One week later she was taken ill with high fever and headache which was later diagnosed as ulcero-glandular tularemia in regional lymph nodes, caused by Francisella tularensis. Recovery was only achieved after several weeks of systemic antibiotic treatment (Gentamicin/ Ciprofloxacine). Tularemia is a well known zoonotic disease, called "rabbit fever", mainly affecting rabbits and hares, but also small rodents. Human infection occurs often following tick bites or bloodsucking insects, or in hunters or slaughterers handling infected animals. Bites by mice have also been reported as a cause of tularemia. For the first time we report this case of tularemia as a result of an attack by a bird of prey. We assume that the bird acted as a vector just carrying the F. tularensis on its claws or beak, but we cannot exclude an infection of the bird itself. Several other joggers had also been attacked by a common buzzard in the same area shortly after the above described event and one of these also became infected with F. tularensis.

Small ruminants infected with scrapie show a large range of often unspecific clinical symptoms. The most-often described signs, locomotion, sensibility and behavioural disorders and emaciation, rarely occur together, and cases have been described in which only one of those signs was detectable.Thus, formulating a well-circumscribed definition of a clinical suspect case is difficult. Most animals with CNS-effecting diseases such as listeriosis, polioencephalomacia, cerebrospinal nematidiasis and enterotoxemia will, in a thorough neurological examination, show at least some scrapie-like symptoms. Among the 22 neurological field cases examined in this study, a goat with cerebral gliomatosis and hair lice showed the closest similarity to clinical scrapie. The unilateral deficiency of the cerebral nerves has potential as an clinical exclusion criterion for scrapie. However, the laboratory confirmation--or exclusion--of scrapie remains important. It thus needs to be realized that a consistent and thorough examination of neurologically diseased small ruminants (including fallen stock) is the backbone of a good surveillance system for these diseases. This should be a motivation for submitting adult sheep and goats for neuropathological examination.

This report describes border disease in a flock of sheep in Switzerland. In April 2001, three ewes in a flock of 41 sheep gave birth to lambs that had generalized tremors and excessively hairy fleece. One of these, a three-week-old female lamb, was referred to our clinic for further diagnostic work-up. The lamb was very nervous, bleated constantly and had generalized muscle tremors, which were more pronounced in the head region. Hind end ataxia was observed, and the lamb was slow to correct its posture when the hind limbs were abducted, adducted or crossed. Blood samples were collected every six weeks to determine antibody titres to pestivirus and for virus isolation via cell culture. A skin biopsy sample was also collected and examined immunohistochemically for pestivirus antigen. Antibody titres in the first tests were suspicious and those of the second were negative. Pestivirus was identified in cell culture, and the skin biopsy sample was positive for pestivirus antigen. Blood samples were collected from all of the ewes and lambs and the buck for virus isolation via cell culture and determination of pestivirus antibody titres. Thirty-one animals were seropositive, six had borderline antibody titres and four were seronegative. Pestivirus was isolated from eight animals, which included the lamb described in this report. Of the virus-positive animals, three were seronegative, three others had borderline titres and two were seropositive. Six of the eight viruses isolated from cell culture were further characterized genetically via retrotranscription and polymerase chain reaction and subsequent sequencing. The phylogenetic analysis revealed that the causative agent was border disease virus. This is the first time that border disease virus has been isolated in Switzerland. The lamb referred to our clinic was observed for three months; it was then euthanatised and a postmortem examination was performed. Immunohistochemical examination of numerous organs revealed pestivirus antigen. The source of infection was though to be infected sheep from another flock, which shared a pasture. All antigen-positive animals were slaughtered.

Malignant catarrhal fever (MCF) is a mostly fatal lymphoproliferative disease of cattle. In 1995 a PCR based method was introduced for the detection of the ovine herpesvirus 2 (OvHV-2), which is regarded as the causative agent of the sheep-associated form of the disease. This PCR can be regarded as a gold standard for the in vivo diagnosis of sheep-associated MCF in cattle (Müller-Doblies et al., 1998). This semi-nested PCR was now used as a reference test for the reassessment of diagnostic criteria in the clinical and post mortem diagnosis that could previously not be quantitated. Based on 83 suspected cases with a complete clinical record the clinical signs were weighted and grouped according to their sensitivity and specificity into lead signs indicative of MCF and frequently accompanying signs supportive for the diagnosis of MCF and general clinical signs that were less reliable for the diagnosis. Differential diagnoses are discussed, which are of particular significance due to their status as OIE list A diseases e.g. foot-and-mouth disease or rinderpest. 38 PCR confirmed cattle with MCF served for the quantitative analysis of organ lesions. For the post mortem diagnosis an essential set of organ samples is defined to permit a reliable histological diagnosis, as the gross pathology often did not give any indication for the diagnosis. These criteria should help to improve the diagnostic efficiency and to select the appropriate laboratory diagnostic procedures for MCF-suspected cattle.

Borna disease (BD) is a rare immunopathological disorder of the central nervous system (CNS) caused by infection with Borna disease virus (BDV) and histologically characterized by mononuclear encephalomyelitis. BD primarily affects equines and sheep in well defined endemic areas of central Europe, but BDV infections have also been reported in other host species including humans, as well as in non endemic regions. In this paper recent data on the pathogenesis of BD are reviewed and the current situation in Switzerland and the Principality of Liechtenstein is summarized.

This study involved 182 calves, heifers and cows that were the first generation progeny of cows with bovine spongiform encephalopathy (BSE). All animals underwent clinical and neurological examinations. Blood, milk, urine, ruminal fluid and cerebrospinal fluid samples were examined. Each cow underwent a specific examination for BSE which included assessment of behaviour, sensitivity and locomotion. This examination was performed twice, and there was very good agreement between the results. The most common symptom was nervousness (14 animals). In the first examination, 68 animals were mildly to moderately sensitive to touching of the head, 44 animals were hypersensitive to a halogen light and 35 animals were hypersensitive to a camera flash. Twenty-four animals reacted by kicking when the hindlimbs were touched with a broom. None of the animals had disturbances in locomotion. Based on the interpretation of all findings and the comparison of the results of the first and second examinations, 173 animals were diagnosed as free of BSE. In 9 animals, the disease could not be ruled out; however, it could not be confirmed in any of them. Histological and immunohistochemical examinations of the brain of all animals were negative for BSE (see Part 2 of the study for details). The results of this study indicate that abnormal clinical findings may occur in clinically healthy cattle. However, none of the progeny of cows with BSE exhibited clinical signs typical of BSE, such as disturbances in behaviour; sensitivity and locomotion.

In order to detect lesions of a spongiform encephalopathy and/or accumulation of the protease resistant prion protein (PrPres), 182 offspring of cows affected with BSE were examined neuropathological and immunohistochemically. Neither spongiform encephalopathy nor PrPres accumulation were found. In seven animals other neuropathological lesions were seen, significant ones in three. Because of the small risk of exposure to contaminated feed in these animals, nearly all of which were born after the introduction of the protein feed ban for ruminants, the occurrence of spongiform encephalopathy in this series of BSE offspring would be suggestive of maternal transmission. However, the value of the study in this respect is quite limited. Only half of the animals were old enough to develop clinical and pathological evidence of the disease. If a maternal effect on the risk for the offspring is only to be expected during the last 6 months of the incubation of the dam as suggested by British investigations, only few animals in this study would fulfil the requirement of having been born during this critical period. Since it cannot be entirely excluded that the BSE agent transiently invades extraneural tissues in the early stages of infection, the above mentioned restriction to the final 6 months of the incubation time of the dam would not necessarily be applicable to all situations. We concluded that this study supports previous observations according to which maternal transmission of BSE is at best a rare event.

A three-week-old foal was submitted to the clinic because of a minor traumatic injury at the lower jaw. At admission the foal exhibited diarrhea, a distended abdomen and reduced general condition. These findings could not be associated with the injury. On abdominal radiography decreased abdominal detail and a dorsocaudal displacement of the intestine was present. Ultrasonographically multiple fluid-filled cystic structures of several centimeters in diameter were identified. These cystic structures appeared to be associated with the liver. At laparotomy and at necropsy the liver was markedly enlarged and firm and had large, thin-walled, with a bile-like fluid filled cysts, 4-20 centimeters in diameter. Histological lesions were characterized by proliferation of small bile ducts and of interlobular connective tissue as well as focal subacute cholangitis. Gross and histological findings were considered to be consistent with congenital polycystic liver disease and fibrosis with ascending cholangitis.

Persistent infection with the Bovine Viral Diarrhea/ Mucosal Disease Virus (BVDV) can be detected using immunohistological methods. The experiments show that the LSAB (Labeled Streptavidin Biotin) peroxidase method is suitable to detect the BVDV in cryostat sections of unfixed tissue. For the diagnostic work up in living animals, skin biopsies give reliable results. In dead animals, organs such as thyroid gland, skin, mucosa of the mouth, esophagus and abomasum are well suitable for immunohistological BVDV detection.

The histopathologic, immunohistochemical and electronmicroscopic findings of four dysautonomic cats are presented. The main histopathologic changes were seen in the nervous system, e.g. in sympathetic and parasympathetic ganglia that were similarly affected. Acute cases showed a degeneration of most of the neurons, in one subacute case less neurons and degeneration of some of the remaining neurons were present. Degenerating neurons were swollen or shrunken and had pycnotic, eccentric nuclei. The Nissl substance was lost, the cytoplasma stained eosinophilic and was often vacuolated. Degenerating neurons were also seen in some nuclei of cranial nerves. In sympathetic ganglia numbers of glial cells were increased as shown by immunohistochemical markers (GFAP, S-100). The main ultrastructural changes in sympathetic ganglia were eccentric, crenated nuclei, loss of Nissl substance, loss of ribosomes, distended cisternae and vacuoles filled with floccular material. Circular stacks of parallel smooth-membranes and autophagic vacuoles were also often seen. No normal Golgi fields were seen. These findings closely resemble those already described for feline dysautonomia.

A 9-year-old horse had numerous firm, painless nodules of the skin and subcutis. Moderately vascular granulation tissue with numerous uni- or multinuclear reticuloendothelial cells was in the nodules and the regional lymph nodes but not in the viscera. By using special stains and electron microscopy, widespread amyloid deposits, mainly in the cytoplasm of reticuloendothelial cells, were identified. Amyloid was probably produced within the reticuloendothelial cells, then expelled from the dying cell and deposited in the intercellular space.

Hypotrichosis and oligodontia associated with a chromosomal anomaly (Xq-deletion) are described in a 11-month old cattle (Simmenthal/Red Holstein cross-breed). This chromosomal anomaly was accompanied with hairlessness and grievous teeth abnormalities. The animal had a very thin haircoat, had only one incisor and between one to three molars per mandible or maxilla. This resulted in reduced food intake, reduced rumination, and retarded growth. Post-mortem examination revealed lesions in the kidneys (bilateral chronic interstitial nephritis), adrenals (hyperplasia), pancreas (focal fibrosis) and abomasum (obstipation and multiple ulcers). Some of these abnormalities are comparable with the human "anhidrotic ectodermal dysplasia" (Christ-Siemens-Touraine syndrome) and supports the hypothesis that there are homologies in the X-chromosome of different mammals.

The clinical signs and pathological lesions, consistent with Bovine Progressive Degenerative Myeloencephalopathy (BPDME), are described in a heifer. The animal was an 18-month-old Braunvieh-/Brown Swiss crossbreed with 50% Brown Swiss. Both the sire as well as the dam were related to the bull "B.". The only neurological signs were a posterior ataxia. Mobility and coordination of the front legs were normal. The CK activity of the cerebrospinal fluid was enhanced. There was a moderate to severe degeneration of the white matter consisting of marked axonal degradation and distension and degradation of myelin sheats in all parts of the spinal cord as well as in the medulla oblongata. The lesions were more severe in the descending than in the ascending tracts.

During a canine distemper epidemic in Switzerland in 1984/85 six cases of spontaneous mixed infections of distemper virus and Toxoplasma spec. were diagnosed. An etiologic diagnosis was made by immunohistological PAP-labelling. Pathological including histopathological findings are reported. The possibilities of histological identification of the organisms (H & E staining) are compared with immunohistology. The importance of spontaneous opportunistic infections involving protozoa is discussed.

Two spontaneous cases of Bornea disease in rabbits are reported. With the help of fluorescence-serological methods it was possible to detect virus-specific antibodies in the brain and serum of both animals. Demonstration of viral antigen in the brain is a valuable supplement to cell culture from brains. The findings confirm earlier reports that the natural host spectrum of Borna virus includes the rabbit, in addition to the horse and sheep.