[Food hygiene and safety - What is your diagnosis?] / Lebensmittelhygiene ­ Was ist Ihre Diagnose?

INTRODUCTION: A healthy, 1,5 year old female wild boar (Sus scrofa) was shoot in a hunting district in Switzerland on June 22, 2023. The meat inspection revealed noticeable skin changes on all four distal extremities which were described histologically as multifocal epidermal hyperplasia and moderate orthokeratotic hyperkeratosis. The rest of the animal body, the organs and the lymph nodes were without any obvious lesions. The diagnosis of papilloma virus-associated exophytically growing papillomas was made. The venison was approved as fit for human consumption.

INTRODUCTION: Un sanglier femelle (Sus scrofa) en bonne santé, âgé d'un an et demi, a été abattu dans le nord de la Suisse le 22 juin 2023. L'inspection de la viande a révélé des modifications cutanées notables sur les quatre extrémités distales des membres qui ont été décrites histologiquement comme une hyperplasie épidermique multifocale et une hyperkératose orthokératosique modérée. Le reste du corps de l'animal, les organes et les ganglions lymphatiques ne présentaient aucune lésion évidente. Le diagnostic de papillomes à croissance exophytique associés à des papillomavirus a été posé. La venaison a été déclarée propre à la consommation humaine.

[Molecular and immunodiagnostic studies of bovine neosporosis in Switzerland]. / Molekular- und immundiagnostische Untersuchungen zur bovinen Neosporose in der Schweiz.

Cyst-forming coccidia may cause significant losses in livestock, primarily due to abortion, loss of young animals and neuromuscular diseases. Rather recently, Neospora caninum has been recognized as one of the major protozoal abortion-inducing parasites in cattle. The present study addressed the performance of different diagnostic tools (in vitro-cultivation; histology; immunohistochemistry; serology; PCR) suitable for the direct or indirect detection of N. caninum. By PCR, Neospora-DNA was detected in 24 brains (29%) from 83 bovine abortion, many of these brains were simultaneously characterized by histopathological findings typical for a protozoal, cerebral parasitosis. The diagnostic methods were furthermore assessed using samples of different tissues and body fluids from three experimentally Neospora-infected pregnant cows and their foetuses. The diaplacental passage of N. caninum to the foetus was successful in two of the three cases. In these two cases, PCR was positive for different foetal organs and, additionally, for the abomasal and amniotic fluid. The successfully infected cows developed anti-Neospora serum antibodies between 10 and 17 days post infection, foetuses remained serologically negative in all cases. The results obtained in the present study demonstrated the usefulness of PCR, complemented by serology, for the specific diagnosis of bovine neosporosis. Such tests may prove suitable to perform epidemiological investigations. Taken together, our data indicated that prenatal neosporosis may be an important cause of infectious bovine abortion in Switzerland.

Comparative detection of classical swine fever virus in striated muscle from experimentally infected pigs by reverse transcription polymerase chain reaction, cell culture isolation and immunohistochemistry.

Classical swine fever (CSF) is a highly contagious viral disease, which can be transmitted by CSFV-contaminated swill. In 1993, four CSF outbreaks in Switzerland were caused presumably by feeding pigs with improperly heated swill. The aim of the investigations was to find a suitable method for CSFV detection in striated muscle samples of infected pigs in order to allow routine testing of meat for virus contamination. The sensitivity of virus detection in striated muscle was compared with the detection in target organs. Using reverse transcription polymerase chain reaction (RT-PCR), cell culture isolation and immunohistochemistry on samples from 14 experimentally infected pigs, CSFV was detected in target organs of ten, and in striated muscle of six pigs, respectively. Overall, only 58% of muscle samples from CSFV-positive animals were positive by RT-PCR and 40% by virus isolation in cell culture, whereas the virus was detected in target organs of these pigs. Virus detection from striated muscle was primarily successful in severely diseased animals infected with highly virulent CSFV strains. It is concluded that striated muscle is not suitable for sensitive CSFV detection, and additional organs have to be examined for reliable diagnosis.

[Bovine virus diarrhea/mucosal disease in cattle--clinical findings in 103 calves and cattle]. / Bovine Virusdiarrhoe/Mucosal Disease beim Rind--Klinische Befunde bei 103 Kälbern und Rindern.

One hundred and three calves and heifers persistently infected with BVD virus were examined. The most important clinical findings in order of frequency were weight loss, erosions of the oral mucosa, diarrhea, anorexia and fever. In addition, nasal discharge, lymph node enlargement, erosions of the nose, muzzle and interdigital cleft and bronchopneumonia occurred in less than half of the patients. Furthermore, crustaceous dermatitis was observed in three patients and petechial hemorrhage of the oral mucosa occurred in two other cases with severe thrombocytopenia. Haemoconcentration, leukocytosis, hyperfibrinogenemia and azotemia were the most important haematological findings. To confirm the clinical diagnosis, the serum antibody titre of 69 patients was compared with that of a clinically healthy control animal from the same herd. There was no positive antibody titre in 65 of the 69 patients, whereas 67 of the control animals had positive titres. In 34 patients, EDTA blood samples were collected for virus detection. In 20 of these, skin biopsy samples were also obtained for virus demonstration. Virus has been demonstrated in the blood of 32 of the 34 cases and in all 20 skin biopsy specimens.