Three types of combined respiratory vaccine containing Infectious Bovine Rhinotracheitis (IBR), Bovine Viral Diarrhoea (BVD) and Parainfluenza -3 (PI-3) viruses were prepared from the local isolates grown in MDBK cell line, inactivated by binary ethyleneimine (BEI) and adsorbed with different adjuvants, DEAE-Dextran, alhydragel and mineral oil adjuvants were compared immunologically for the choice of the most preferable one for vaccine production.
All types of the prepared vaccines were safe when tested in guinea pigs and calves. Potency test was performed by immunization of susceptible calves which were divided into 3 groups each group was inoculated by one type of vaccine and the third group was kept as control. Two intramuscular injections of each vaccine were administered at an interval of two weeks.
The results indicated a variation in kinetics of the development of serum neutralizing (SN) against all component of the vaccine and haemagglutinating antibodies against PI-3virus in sera of all vaccinated calves 6 months after Inoculation.
The protective capacity of each vaccine was studied when the vaccinated animals were challenged one month post vaccination, neither thermal reactions nor virus isolation could be detected. Under the conditions of these experiments a significant higher degree of immunogenicity was demonstrated with DEAE dextran adjuvant vaccine.