Detection of polychlorinated biphenyls and dioxins in Belgian cattle and estimation of the maximal potential exposure in humans through diets of bovine origin.

The methodology used to detect a polychlorinated biphenyl (PCB)/dioxin contamination in a Belgian cattle population that was not exposed to the PCB/dioxin incident in 1999 is presented. This population is directly or indirectly destined for human consumption. The methodology consisted in the systematic sampling of all calf-fattening stations and groups of cattle destined for export, and in the random sampling of slaughter cattle.

Prevalence of paratuberculosis (Johne's disease) in the Belgian cattle population.

The national bovine paratuberculosis (PTB) seroprevalence (apparent prevalence) in the Belgian cattle population was determined by a serological survey that was conducted from December 1997 to March 1998. In a random sample of herds (N=556, 9.5%), all adult cattle of 24 months of age or older (N=13,317, 0.

Prevalence of bovine herpesvirus-1 in the Belgian cattle population.

The national bovine herpesvirus 1 (BHV-1) seroprevalence (apparent prevalence) in the Belgian cattle population was determined by a serological survey that was conducted from December 1997 to March 1998. In a random sample of herds (N=556), all cattle (N=28478) were tested for the presence of antibodies to glycoprotein B of BHV-1. No differentiation could be made between vaccinated and infected animals, because the exclusive use of marker vaccines was imposed by law only in 1997 by the Belgian Veterinary Authorities.

Evaluation of parenteral vaccination methods with glycoproteins against Aujeszky's disease in pigs.

A comparative evaluation of vaccination methods with glycoproteins for the induction of immune responses and protection of the pig against Aujeszky's disease virus (ADV) was performed. Different vaccination routes (intradermal (i.d.

Inhibition of virus replication in the tonsils of pigs previously vaccinated with a Chinese strain vaccine and challenged oronasally with a virulent strain of classical swine fever virus.

After an oronasal (O.N.) infection with classical swine fever (C.

An epizootic of African swine fever in Belgium and its eradication.

In March 1985 an outbreak of African swine fever was diagnosed in Belgium, in the province of West Flanders. The source of the infection was probably pork imported from Spain which was fed to only one boar. A total of 12 farms were infected in the epizootic out of 185 farms which were in contact.

Epizootics of respiratory tract disease in swine in Belgium due to H3N2 influenza virus and experimental reproduction of disease.

In Belgium, influenza virus was isolated from swine in 22 epizootics of respiratory tract disease in swine during 1984. In 8 of the epizootics, H3N2 influenza virus, related to the A/Port Chalmers/1/73 strain, was isolated. Intratracheal inoculation of the isolates induced clinical signs.

Comparison of serological tests used in three state veterinary laboratories to identify maedi-visna virus infection.

Three immunoassays used in Dutch, Belgian and British state veterinary laboratories for the detection of antibodies to maedi-visna virus were compared. These were an indirect enzyme-linked immunosorbent assay (ELISA), an indirect immunofluorescence test (IIFT) and an agar gel immunodiffusion test (AGIDT). The results indicated that all three assays were of similar sensitivity and specificity with identical results being recorded for 91 of 100 samples.

Vaccination of cattle against pseudorabies (Aujeszky's disease) with homologous virus (herpes suis) and heterologous virus (herpes bovis 1).

Study was made to determine whether vaccination of cattle against pseudorabies (PR; Aujeszky's disease) affords protection upon subsequent intranasal challenge exposure with virulent virus. Vaccinations were performed with a commercially available oil-adjuvant PR virus vaccine, in some cases supplemented with A1(OH)3 (given subcutaneously), with the attenuated NIA4 strain of PR virus (given intranasally), and with a commercially available temperature-sensitive mutant of bovine herpesvirus-1 (infectious bovine rhinotracheitis [IBR] virus) given intranasally. Challenge exposure was performed intranasally with 10(3) median lethal doses (LD50) of the virulent PR virus.