Production of a falcon herpesvirus vaccine.
ABSTRACT Ten common kestrels (Falco tinnunculus) were used for this falcon herpes vaccine experiment. Four kestrels were subcutaneously given 1 ml of an attenuated falcon herpesvirus that had originally been isolated from the liver of an American prairie falcon (Falco mexicanus). This virus was then passaged 100 times on chicken embryo fibroblast cells (CEF-cells). Another 4 kestrels were given subcutaneously an inactivated falcon herpesvirus vaccine derived from the same American field strain. This vaccine was concentrated, inactivated by heat and betapropiolactone and emulsified in complete Freund's adjuvans. Two further kestrels served as controls and were not vaccinated. Twenty-one days after vaccination, all 10 kestrels were challenged with passage 3 of the American falcon herpesvirus. The 2 control kestrels died 6 days after challenge and 3 of those given the inactivated herpes vaccine died 9 days after challenge, with typical lesions of herpesvirus inclusion body hepatitis. Before the vaccination experiment, all 10 kestrels were free of serum neutralising antibodies to the falcon herpesvirus. Twenty-one days after vaccination, all 4 kestrels vaccinated with the attenuated vaccine, and one vaccinated with the killed vaccine, had seroconverted, having shown no symptoms to the challenge with a low passage virulent American herpesvirus strain. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there is no danger for any other birds from the attenuated herpesvirus vaccine. This experiment clearly shows that an attenuated falcon herpesvirus vaccine can protect kestrels from fatal inclusion body hepatitis.
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ABSTRACT: Four Gyr hybrids were used for this falcon herpes vaccine experiment. Three falcons were given 1 ml of an attenuated falcon herpesvirus vaccine (DuFaHe) subcutaneously twice within 14 days, whereas the fourth falcon was used as a control. Eighteen days after the booster vaccination, all four Gyr hybrids were intranasally and ocularly challenged with a virulent low-passage falcon herpesvirus. The control falcon died 9 days after challenge with typical lesions of herpesvirus inclusion body hepatitis. The three vaccinated falcons seroconverted and did not show any symptoms. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there was no danger for any other birds from DuFaHe. This experiment shows that falcons can be protected from herpesvirus infection by an attenuated herpesvirus vaccine. However, it should be stressed that only four falcons were used for this experiment.Journal of Veterinary Medicine Series B 01/2002; 48(10):727-32. DOI:10.1046/j.1439-0450.2001.00490.x · 1.57 Impact Factor