genetic typing methods of t. gondii strains have been extensively perfected in recent years. from a technical point of view, many tools usable for genetic studied on single-copy loci have been used: rflp, pcr-rflp, sequencing, rapd-pcr and isoenzyme analysis. we described the cloning and sequence analysis of the gene which encodes the major surface antigen (sag1 or p30) of t. gondii. sag1 is th...

OBJECTIVE To evaluate cross protection provided by administration of contagious ecthyma vaccines against strains of orf virus in goats. ANIMALS 126 Boer-Spanish crossbred goats (3 to 20 days old). PROCEDURES 85 goats were vaccinated with a goat-derived contagious ecthyma vaccine. Of these, 41 were challenge exposed with the virus strain for the contagious ecthyma vaccine, 40 were challenge ...

BACKGROUND Influenza-associated morbidity and mortality has not decreased in the last decade, despite increased receipt of vaccine. To improve the immunogenicity of influenza vaccine, a high-dose (HD) trivalent, inactivated influenza vaccine was developed. METHODS A multicenter, randomized, double-blind controlled study was conducted to compare HD vaccine (which contains 60 microg of hemagglu...

The currently used vaccine strain of Rinderpest virus was derived by serial passage of the highly virulent Kabete 'O' strain (KO). A full-length cDNA copy of the KO strain was made from which a virus identical in pathogenicity to the wild-type virus was rescued. A series of chimeric viruses was prepared in which the coding sequences for the N, P, F, H or L proteins were replaced with the corres...

background and aims: infectious bursal disease (ibd) is an acute contagious viral disease of birds worldwide. the causative virus induces a persistent immune suppression following destroy b lymphocytes precursors in bursal lymphoid follicles. vaccination is the main strategy for prevention of the disease in commercial poultry industry. materials and methods: to produce a live vaccine against th...

A purification procedure of pertussis toxin (PT) from submerged culture of Bordetella pertussis (B.pertussis) strain 134 using adsorption and affinity chromatography was discussed. The yield of the resulting PT was approximately 37.5mg/l of concentrated culture supernatant. The polypeptide pattern of the purified PT was investigated by SDS-PAGE and showed five bands between 11 to 26 KDa using l...

Compared to other methods of vaccine production, (e.g. culture flask and bioreactor system), the roller culture method for producing rabies vaccine is simpler, and the equipment easier to install and maintain, and also in the event of contamination of one roller, the entire batch need not be discarded. This system provides a much larger surface area than the culture flask, and also ensures a mu...

OBJECTIVE To compare immunologic responses and reproductive outcomes in sows housed under field conditions following controlled exposure to a wild-type strain of porcine reproductive and respiratory syndrome virus (PRRSV strain WTV) or vaccination with a modified-live virus (MLV) vaccine. DESIGN Randomized controlled trial. ANIMALS 30 PRRSV-naïve 10-week-old female pigs. PROCEDURE Humoral...

a purification procedure of pertussis toxin (pt) from submerged culture of bordetella pertussis (b.pertussis) strain 134 using adsorption and affinity chromatography was discussed. the yield of the resulting pt was approximately 37.5mg/l of concentrated culture supernatant. the polypeptide pattern of the purified pt was investigated by sds-page and showed five bands between 11 to 26 kda using l...

Salmonella enterica serovar Choleraesuis strain C500 is a live vaccine attenuated by chemical methods. Here, we report the complete genome sequence of the strain, which may be helpful for elucidating the attenuation mechanism of the vaccine strain.