Reptile virology.

Reptiles are hosts to diverse viral infections. This article reviews the viruses that are known to infect reptiles and discusses associated pathology, available diagnostic methods, and management techniques for the reptile clinician.     

Establishment of an immunological labelling of pigs using synthetic peptides

The objective of this study was to develop a suitable combination consisting of synthetic peptides, carrier protein and adjuvant for immunological labelling of pigs. Specific antibody titres were evaluated by ELISA technique. From 9 peptides 4 were excluded from following investigations showing cross reactivity or low immunogenic effects, sufficient anti-peptide titres were achieved by 5 peptides. Labelling control is possible after 7 days at the earliest and can be used for the whole fattening period after single immunization using an effective carrier-adjuvant-combination. Mixing of peptides in one labelling dose had no negative influence on titres against single peptides. Different combinations of 4 carriers (keyhole limpet haemocyanin (KLH), palmitic-acid-3-cystein-acid (Pam3Cys), palmitic acid (Pam) and dextran) and 4 adjuvants (Montanide IMS 1313, Montanide ISA 25, Quil A and Diluvac forte) were tested. Optimal labelling could be seen by combination of 50 nmol peptide, KLH as carrier and Montanide IMS 1313 as adjuvant. Generally after booster injection titres were higher, however, a booster dose was not necessary using most effective adjuvants. A less immunogenic, but cost effective alternative for short time labelling (7 weeks) was a peptide-Pam3Cys-conjugate (75 nmol) combined with Quil A as an adjuvant (2 mg/ml). Immunological labelling of pigs is recommended as a good method for tracing back the origin of animals and meat products. It may be also used for vaccine labelling to prove vaccination of pigs.     

Methodology in diagnostic virology.

Selection of proper assays and appropriate interpretation of results can be a challenge to the veterinary clinician. Assays vary in methodology, sensitivity, and specificity. These assays can be invaluable in attaining the correct diagnosis, but a clear understanding of the assay and the results is essential. To this end, communication with the laboratory personnel is crucial. Optimal sample selection, shipping recommendations, assay selection, and interpretation should be discussed with the laboratory staff.     

Amphibian virology.

Amphibians are a diverse group of species; much work remains to be done to elucidate the viruses of amphibians. Viral diseases may play an important role in wild and captive amphibian populations. Iridoviruses are a leading cause of wild amphibian mortality events in the United States and are a common cause of amphibian mortality events worldwide. In addition to frank viral diseases, viral infections may play a role in the establishment of bacterial, fungal, and parasitic diseases and are an underlying cause of neoplasia. It is important for the amphibian clinician to recognize disease syndromes and pathology that are consistent with viral etiology.     

Recent advances in avian virology.

Selected, recent research on the following avian diseases, and their causative viruses, has been reviewed: chicken anaemia, infectious bursal disease, turkey rhinotracheitis, avian nephritis, fowlpox, influenza, infectious bronchitis and turkey enteritis.     

Small mammal virology.

Most viral infections in small mammals are transient and rarely produce clinical signs. When clinical signs do appear, they are often of a multifactorial etiology such as respiratory infection with Sendai virus and the bacteria M. pulmonis in rodents. Diagnosis is generally made based on clinical signs, while therapy involves treatment for concurrent bacterial infections and supportive care. Small mammals may carry zoonotic viruses such as LCMV, but natural infections are uncommon. Viral diseases are rare (or largely unknown) for hedgehogs, chinchillas, and prairie dogs, while no known naturally occurring, clinically relevant viral diseases exist for gerbils and sugar gliders. This article is intended to aid the clinician in identifying viral infections in small mammals and to help determine the significance each virus has during clinical disease.     

The beginnings of animal virology in Germany

Animal virology started in 1898 with the discovery of FMD virus. The finding resulted from a close collaboration between Friedrich L?ffler (University of Greifswald) and Paul Frosch (then at Robert Koch's institute in Berlin). Their work in Greifswald was greatly hampered by the danger of dissemination of foot and mouth disease in the surroundings. Therefore L?ffler proposed to set up a research unit on the Island of Riems in the Baltic Sea. In the Fall of 1910 work could start in the Research Institute Riems Island. A great foreward step was set when L?ffler's successor, prof. Otto Waldmann, succeeded in 1920 in transmitting the infection to guinea pigs by intradermal inoculation in the hind pad. Under Waldmann's aegis the Riems developed into a full-fledged FMD research station. The most important achievement for veterinary medicine was the development of a vaccine in 1938 that proved efficient and safe. Today, the Riems laboratories form part of the Federal Research Centre for Virus Diseases of Animals, together with the Tübingen Unit.     

General concepts of virology.

A basic understanding of viruses and how they replicate and produce disease can aid in the management of virus infections. Parameters, such as clinical signs, sample and test selection, prognosis, and control, are implicit in this understanding. Information increases almost daily about known and emerging viruses; this impacts our ability to manage and control infections.     

Generation and characterization of anti-leptin antisera against synthetic peptides and recombinant protein

The objective of this study was to generate antisera against recombinant bovine leptin and synthetic oligopeptides corresponding to the amino acid sequence 21-40 and 91-110 of bovine leptin. Recombinant bovine leptin was raised in the 293 cells and purified from 10 L of conditioned medium and utilized for immunization. The synthetic peptides were conjugated with keyhole limpet hemocyanin and inoculated into rabbits for antibody generation. Antibody titer was monitored by enzymeimmunoassay, immunoblotting and sandwich binding assay techniques. Each of the antisera, against three different antigens, was found to react with bovine leptin. The titers of anti-peptide antisera were lower than that of anti-recombinant leptin antiserum. Since anti-recombinant leptin antiserum was not neutralized by the leptin peptides 21-40 and 91-110, it is suggested that each antiserum recognizes a distinct epitope. In immunoblot analyses, all antisera exhibited cross-reactivity with human and mouse leptins. However, in the sandwich binding assay, the combination of anti-peptide antisera and anti-recombinant leptin antiserum, originated from bovine leptin, did not cross-react with either human or mouse leptin. The discrepancy of antigenic recognition between the immunoblot analyses and sandwich assay is thought to be dependent on the conformational status of leptin molecules between the species. The antisera generated in this study, which recognized distinct epitopes of bovine leptin, will provide a useful tool for studies of bovine leptin functions.     

Use and abuse of pyrethrins and synthetic pyrethroids in veterinary medicine

Pyrethrin and pyrethroid insecticides are widely used in veterinary medicine for agricultural and domestic purposes. Although pyrethrins and pyrethroids are generally regarded as safe to animals, there have been reports of systemic poisoning in veterinary species. This review summarises the use of pyrethrins and pyrethroids in companion and food producing animals, including their mechanism of action and toxicity. The toxicokinetics of pyrethrins and pyrethroids are described, including absorption, distribution, metabolism (including interactions with other compounds affecting drug metabolising enzymes) and excretion, leading to the application of toxicokinetic/toxicodynamic concepts. Specific cases of pyrethroid poisoning in laboratory animals (including age-related toxicity), fish, companion and large animals are considered, including the high incidence of feline pyrethroids toxicosis following the extra-label use of topical formulations.     

Congress report on progress in pestivirus virology

Summary

This mini‐review highlights new information on various research aspects presented by specialists from all over the world at the 4th Pestivirus meeting held in Giessen (Germany) from March 15–19, 1999. Especial attention is paid towards differences in humeral and cellular immune response of naive and persistently infected calves with BVDV, and towards BVD eradication programmes m the Scandinavian countries.

The development of techniques for an early diagnosis of CSF in live pigs and the progress on both sub‐unit and MLV marker vaccines against this disease are reported.     

Congress report on progress in pestivirus virology

This mini-review highlights new information on various research aspects presented by specialists from all over the world at the 4th Pestivirus meeting held in Giessen (Germany) from March 15-19, 1999. Especial attention is paid towards differences in humeral and cellular immune response of naive and persistently infected calves with BVDV, and towards BVD eradication programmes in the Scandinavian countries. The development of techniques for an early diagnosis of CSF in live pigs and the progress on both sub-unit and MLV marker vaccines against this disease are reported.     

Molecular virology of feline calicivirus.

Caliciviridae are small, nonenveloped, positive-stranded RNA viruses. Much of our understanding of the molecular biology of the caliciviruses has come from the study of the naturally occurring animal caliciviruses. In particular, many studies have focused on the molecular virology of feline calicivirus (FCV), which reflects its importance as a natural pathogen of cats. FCVs demonstrate a remarkable capacity for high genetic, antigenic, and clinical diversity; "outbreak" vaccine resistant strains occur frequently. This article updates the reader on the current status of clinical behavior and pathogenesis of FCV.