Because of the technical problems and length of time involved in the satisfactory performance of the haemagglutination-inhibition test for detection of rubella-specific antibodies, a commercially available passive haemagglutination (PHA) kit utilising rubella antigen-sensitised human erythrocytes was tested for its suitability for use in diagnostic laboratories. The immune response to acute rub...

Strain 0083 and two field isolates of H. paragallinarum were previously converted into NAD-independent organisms by the use of crude DNA extractions from naturally occurring NAD-independent H. paragallinarum isolates. Two of these transformed isolates [0083(T) and A745(T)] were used as DNA donors in another transformation experiment in which another field isolate (M85) was used as the DNA recip...

Development of methods for the diagnosis of viral haemorrhagic disease and the European brown hare syndrome has proceeded at a steady pace over the last few years. The studies conducted by the authors demonstrate that, like VHDV, EBHSV is a calicivirus. The degree of correlation between the two viruses is a key question both for understanding their biology and interpreting the diagnostic result...

Prior to the introduction of the 2009 pandemic H1N1 virus from humans into pigs, four phylogenetic clusters (α-, β-, γ- and δ) of the haemagglutinin (HA) gene from H1 influenza viruses could be found in US swine. Information regarding the antigenic relatedness of the H1 viruses was lacking due to the dynamic and variable nature of swine lineage H1. We characterized 12 H1 isolates from 2008 by u...

A latex enzyme immunoassay (LEIA) for detecting IgG class antibody to rubella virus was compared with the latex agglutination test (LA) and a haemagglutination inhibition assay (HI). Of 243 sera tested, four discrepant results were observed among all three techniques, corresponding to borderline values. Except for one sample containing specific IgM class antibody, the difference between quantit...

Immunomodulatory effects of Flumequine and enrofloxacin were evaluated on humoral immune response of Newcastle disease virus (NDV) vaccinated broiler birds. It was observed that birds receiving flumequine as growth promoter had higher mean body weights, better feed conversion ratio, higher NDV haemagglutination inhibition (HI) antibody, lesser overall mortality, 100% protection against challeng...

BACKGROUND The identification of antigenic variants and the selection of influenza viruses for vaccine production are based largely on antigenic characterisation of the haemagglutinin (HA) of circulating viruses using the haemagglutination inhibition (HI) assay. However, additional to evolution related to escape from host immunity, variants emerging as a result of propagation in different cell ...

Newcastle disease (ND) is a highly contagious and devastating viral disease of poultry and other birds that has a worldwide distribution. ND in pigeons is called paramyxovirosis and is caused by antigenic "pigeon variant" of the virus (pigeon paramyxovirus type 1, PPMV-1). During PPMV-1 infections, central nervous system symptoms and sometimes high mortality are observed. In the case of infecti...

Although vaccination of poultry for control of highly pathogenic avian influenza virus (HPAIV) H5N1 has been practiced during the last decade in several countries, its effectiveness under field conditions remains largely unquantified. Effective HPAI vaccination is however essential in preventing incursions, silent infections and generation of new H5N1 antigenic variants. The objective of this s...