..::Veterinary Serum and Vaccine Research Institute::..

J. Egypt. Vet.Med. Ass. 64,No.3 175-185 (2004)

Some studies on the effect of Virulent infectious Bovine Rhinp Trachitis (IBR)
Viral infection on the Immune response of FMD Vaccinated Calves

SAMIRA, S.TAHA AND FATMA, A. MOUSSA

Veterinary Serum and Vaccine Research Institute,
Abbassia, Cairo , Egypt.

Summary

	Fifteen calves were divided into 5 groups each of 3 animals. First group was vaccinated with FMD vaccine only. The second group was vaccinated with FMD vaccine one week pre-experimentally infected with virulent IBR virus.

	The third group was vaccinated with FMD vaccine one- week post experimentally infected with virulent IBR virus. The fourth group was vaccinated with FMD vaccine and experimentally infected with virulent IBR virus simultaneously. The iffth group was kept as control. The results of this study show that the more effected groups by IBR virus is the 3 rd and 4 th group.

	In which the humoral immunity begin to decrease than the protective value and the 3 rd month post vaccination. Which the 2rd group begin to decline at the 4 th month post vaccination. In comparison with the result of group one in which the animals vacinated only with FMD vaccine were declined at the 5 th mouth. Therefore, the IBR virus has immunosuppresive effect on immune response of animals vaccinated with FMD vaccine.