Brain and testicle tissue from immune rabbits brought in contact with the Levaditi or Noguchi strains of vaccine virus will fix or inactivate the virus. Extracts of normal testicles from susceptible animals enhance to an extraordinary degree the infectivity of both the neuro- and dermal strains of vaccine virus. The Noguchi virus is not affected by testicle extracts when injected into the skin,...

BACKGROUND Potency test for control of rubella vaccine is a significant factor to qualify production line and vaccination program. For this reason, WHO recommends to use the microtitration method by both vaccine companies and control laboratories. Then the study was done to improve this test. METHODS Three rubella virus samples, including an in-house standard, a lot of vaccine and an in-proce...

Introduction Marek’s disease, an economically-important lymphoid neoplasm of chickens, is caused by oncogenic strains of Marek’s disease herpesvirus (MDV). The virus replicates in lymphocytes and the epithelia of the skin and feather tissues (1). Despite very successful vaccination with attenuated virus strains, vaccine failures do occur as field viruses evolve towards greater virulence. In the...

The immunological effectiveness of the Middletown oral poliovirus vaccination program was determined by testing preand post-vaccinal neutralizing antibody levels in blood specimens from a selected group of children, representing about five per cent of the school children and 10 per cent of the preschool vaccinees. The present paper is concerned with the results of these tests in terms of the an...

Hypertrophic osteodystrophy (HOD) is a major manifestation of the hyper-inflammatory syndrome, and causes high fever, pain and lameness associated with swelling of the growth plates in the femur and humerus. This is typically seen in one or two puppies in a genetically susceptible litter, soon after they receive multivalent vaccination, although it also can occur after monovalent vaccination. O...

The dnaK gene and surrounding sequences from reference strains of the six Brucella species were amplified by the polymerase chain reaction (PCR) with primers chosen according to the published sequence of the B. ovis dnaK gene and studied for polymorphism with nine restriction endonucleases. The restriction patterns were identical for all species with all restriction endonucleases tested except ...