Selection of poultry Eimeria strains through extra-intestinal sporozoites
AssigneeWyeth
InventorFrans Gerrit Davelaar
Life of this patent
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Abstract
A method for obtaining an immunogenic strain useful for producing a vaccine against Coccidiosis comprises the cycle of infecting at least one first group of specific pathogen-free donor birds with oocysts from an Eimeria species. Blood is then collected from these donor birds, and is then used to infect a second group of specific pathogen-free birds. Oocysts are collected from the second group of birds. These oocysts are then multiplicated to complete the cycle. The cycle is then repeated using the multiplicated oocysts. After a total of about three cycles, a final antigen may be harvested and utilized as a source to generate oocysts for a vaccine.
Claims30
An isolated strain useful for generating immunogenic oocysts for a vaccine against Coccidiosis.
An isolated strain useful for generating immunogenic oocysts for a vaccine against Coccidiosis, said strain being identified as A3C2A2.
A vaccine effective against Coccidiosis, comprising at least about 104 oocysts of attenuated Eimeria per dose, together with a pharmaceutically acceptable carrier.
A method of inoculating poultry against Coccidiosis, which comprises administering to said poultry at least about 104 oocysts from attenuated Eimeria acervulina.
A method for obtaining an immunogenic strain useful for producing a vaccine against Coccidiosis, which comprises the cycle of:
- a) infecting at least one first specific pathogen-free donor bird with oocysts of an Eimeria species;
- b) collecting blood from said donor bird;
- c) infecting at least one second specific pathogen-free bird with said blood;
- d) collecting oocysts from said second bird;
- and
- e) multiplicating said oocysts to thereby substantially complete said cycle;
- and then repeating said cycle using said multiplicated oocysts from part e), wherein at least about three cycles of said method are completed.
A method for attenuating one or more strains of Eimeria, which comprises successively passaging said strain through at least three sets of specific pathogen-free poultry, wherein each said passaging comprises at least two successive sets of inoculations.
A method for attenuating Eimeria acervulina, which comprises the cycle of:
- a) inoculating at least one first group of specific pathogen-free donor birds with oocysts generated from virulent E. acervulina;
- b) collecting blood from said group of donor birds via bleeding at about 3 to about 6 hours post-inoculation;
- c) inoculating at least one second group of specific pathogen-free donor birds with said blood;
- d) collecting oocysts from said second group of birds;
- and
- e) multiplicating said oocysts to thereby substantially complete said cycle;
- and
- then repeating said cycle using said multiplicated oocysts from sub-procedure e), wherein about three cycles are completed.
Oocysts derived from Eimeria acervulina, said E. acervulina being attenuated by about three cycles of passaging through specific pathogen-free poultry.
A strain of Eimeria having the immunogenic characteristics of the strain E. acervulina deposited with the European Collection of Cell Cultures under accession number 02010911.
A vaccine, said vaccine having the immunogenic response properties of a vaccine against Coccidiosis which contains an immunogenizing amount of oocysts obtained from the strain of E. acervulina deposited with the European Collection of Cell Cultures under accession number 02010911.
Dependencies are inferred from the claim text.