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Immuological and virological studies on fowl pox vaccine
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Abstract: A trial to produce a tissue culture -adapted fowl pox virus vaccine was attempted . In order to reach a suitable virus titer required for optimal immunization of chicks, some of the factors which would influence virus output in culutred cells were studied including cell type, MOI and the addition of DEAE-dextran as well as horse serum to maintenance medium. The Beaudette vaccinal strain of fowl pox virus was used in the study. The results obtained in the present investigation could be summarized as follows:
1- The infectivity tiration of different passages of fowl pox virus on CER, Vero , MDBK, ICR2 and CEF showed that the highest titer was reached in CEF followed by CER.
2- MOI values between 2-5 gave optimal virus ouput.
3- Absence of horse serum in maintenance medium increased the infectivity titer.
4- Addition of 20ug/mi DEAE-dextran proved to be save and non-toxic to the cells, and resulted in a marked increase in virus titer. Under the effect of 13 serial passages and the addition of DEAE-dextran to maintenance medium, an average increase of 3.3 log^10 was achieved in CER cells compared with only 0.6 log^10 in CEF cell culture.
5- A study of Kinetics of multiplication of the 13th passage of the CER adapted Beaudette strain of fowl pox virus in CER cultures showed that the best time for harvestion was 4-5 days post-vaccination and that the virus released in medium was about one log10 higher than the cell associated virus.
6- Patghogenicity assay of the original egg-adapted fowl pox virus strain in both embryonated chicken eggs and susceptible birds revealed titers of 10^9.1 CEID50/mlL AND 10^5.75CEID50/ml for the original strain and 10^9.3CEID50/ml and 10^4.4CEID50/ml for tissue culture adapted strain.
7- Studies on potency (immunogenicity) of tissue culture-adapted Beaudette strain administered by the conventional coutanous route or orally revealed:
-Fourty five days old broiler chickens wing-web method showed 100% takes 10 days post-inoculation and 100% protection when challenged by the wing-web 4 weeks post vaccination.
- Chicks vaccinated through the drinking water at 7 days of age and boostered 21 days later showed a protection rate of about 53.33%
- Others that recievd the 1st dose of vaccine in drinking water at 21 days of age and the second dose 21 days later showed 65.71% protection.
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| Publication year |
1986
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| Availability location |
معهد بحوث الامصال واللقاحات البيطرية-- القاهرة - ش السكة البيضاء - العباسية ص ب 131
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| Availability number |
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| Organization Name |
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| Country |
Egypt
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| Author(s) from ARC |
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| Agris Categories |
Animal diseases
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| Proposed Agrovoc |
Virologiacl;fowl pox vaccine;
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| Publication Type |
PhD Thesis
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