Tolerance and safety evaluation of N,N-dimethylglycine, a naturally occurring organic compound, as a feed additive in broiler diets.

N,N-Dimethylglycine (DMG) is a tertiary amino acid that naturally occurs as an intermediate metabolite in choline-to-glycine metabolism. The objective of the present trial was to evaluate tolerance, safety and bioaccumulation of dietary DMG in broilers when supplemented at 1 g and 10 g Na-DMG/kg. A feeding trial was conducted using 480 1-d-old broiler chicks that were randomly allocated to twenty-four pens and fed one of three test diets added with 0, 1 or 10 g Na-DMG/kg during a 39 d growth period.

Antigenic and phylogenetic studies on a variant Newcastle disease virus using anti-fusion protein monoclonal antibodies and partial sequencing of the fusion protein gene.

A virulent Newcastle disease virus (NDV) isolate, 34/90, reported to show considerable antigenic diversity from more classical strains of NDV, including vaccine strains, was evaluated phylogenetically and for the presence of neutralizing epitopes on the fusion protein. Comparison of a 309 nucleotide sequence of the fusion protein gene of 34/90 with other viruses confirmed the diversity of this virus, placing it in a discrete fifth genetic lineage with an avirulent virus isolated from waterfowl and genetically quite distant from other strains and isolates. The virus-neutralizing mAbs used in the present study were directed against at least seven distinct epitopes on the fusion protein.

Development of an M2e-specific enzyme-linked immunosorbent assay for differentiating infected from vaccinated animals.

Vaccination programs for the control of avian influenza (AI) in birds have restrictions because of some limited efficacy and the difficulty of discriminating between vaccinated and virus-infected poultry. We studied M2e, the highly conserved external domain of the influenza A M2 protein, as a potential differential diagnostic marker for influenza virus infection. The M2 protein is an integral membrane protein, scarcely present on virus particles, but abundantly expressed on virus-infected cells.

Inclusion body disease in snakes: a review and description of three cases in boa constrictors in Belgium.

Inclusion body disease, a fatal disorder in Boidae, is reviewed, and three cases in boa constrictors, the first reported cases in Belgium, are described. The snakes showed nervous signs, and numerous eosinophilic intracytoplasmic inclusions, which are considered to be characteristic of the disease, were found in the liver and pancreas. The disease is suspected to be caused by a retrovirus, but transmission electron microscopic examinations of several tissues from one of the snakes did not reveal particles with a typical retroviral morphology.

Vaccination of chicken embryos with escape mutants of La Sota Newcastle disease virus induces a protective immune response.

To reduce the embryonic pathogenicity of Newcastle disease virus (NDV), escape mutants of the La Sota strain were produced with selected monoclonal antibodies. Immunoselection resulted in the elimination of an epitope by single amino acid substitution (F and HN molecule) or in a conformational change (HN molecule). The embryonic pathogenicity of these escape mutants was reduced and their dose was optimised for in ovo vaccination.