الفهرس 
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Abstract
Capripox viruses infect only ungulates, and most strains of the virus tend to cause clinical disease in only one species (Carn, 1993). Different strains of the virus appear to have different degree of virulence in different species (Kitching and Taylor, 1985). Capripox viruses control without vaccination is extremely difficult in endemic areas. Usually homologous vaccinations incorporating locally prevalent strains of Capripox viruses are quite successful in protecting animals against pox. Therefore, in different countries and sometimes within a country, various live attenuated vaccines have existed from time to time for Capripox with varying degrees of protective efficacy (Ramyar et al., 1974; Dubey and Sawahney, 1975; El-zein et al., 1983; Davies and Mbuugwa, 1985; Guo et al., 1986, Wang and Jiang, 1988a and Mahmood et al., 1989 and 1993).
Attempts to protect either goats with sheep pox virus vaccines or sheep with goat pox virus vaccines are largely unsuccessful (Prasad and Datt, 1973; Agrawal and Soman, 1997).
For this reason four attenuated Capripox vaccines, were prepared from Kenyan sheep pox strain O180, Romanian SP. virus strain; Held GP. Virus strain and bivalent vaccine from R.SPV strain and H.GPV strain.
Vaccines prepared through mixing of the virus fluid with trehalose 10% stabilizer fluid as 1:1 (V:V), then lyophilized under same conditions. Inocuity and activity of different vaccines have been compared. The prepared vaccines were found to have no adverse effects in vaccinated animals.
The prepared vaccines proved sterile, safe and effective in susceptible lambs and kids that previously vaccinated with about 103 TCID50/dose of any homologous or bivalent vaccines, then challenged with the specific virulent virus. No horizontal transmission of viruses from vaccinated into contact control animal. The homologous vaccines also evokes both humoral and cell- mediated immune responses as measured by neutralization test and lymphocyte proliferation assays respectively.
The main characteristics of these vaccines have been verified, in which inoculation of different prepared vaccines were followed by a variable post vaccinal reaction locally and an increase of body temperature which not exceeded one oc.
Mild cross protection was recorded after heterogeneous vaccination in which the lambs vaccinated with ”Held” goat pox vaccine and kids vaccinated with ”Kenyan O180” sheep pox vaccine provide partial protection (about 66%) against viral challenge of immunity. The results explain the varying degree of protectivity within the different strains of SPV vaccines, in which Romanian vaccine outmatch Kenyan O180 vaccine. Results obtained by NI and cellular immunity for any vaccine showed complete correlation with resistance to challenge.
The prepared attenuated bivalent SP and GP, vaccine from R.SP and H.GP, in a recommended doses of both viruses (103TCID50/dose) grant a distinct protection similar or elevated than the homologous vaccines which elicit strong humoral and cellular response in both vaccinated lambs and kids.
Trials for preparation of attenuated bivalent SP and GP vaccine from the locally isolated viruses should be start immediately to cover the demand of the field with safe, potent, inexpensive and highly specific vaccine give long lasting acquired immunity.