VACCINATION AGAINST EIMERIA-MAGNA COCCIDIOSIS USING SPRAY DISPERSION OF PRECOCIOUS LINE OOCYSTS IN THE NEST BOX

Coccidiosis mostly affects young rabbits just after weaning (5- to 6-w eek-old animals). Prevention of this disease must therefore be initiat ed before weaning. 'Precocious lines', derived from field species disp lay good immunogenicity, though not pathogenic when administered at th e right dose. In the present work, we tested the vaccination method of the whole litter at 25 days of age by spray dispersion of oocysts of a precocious line of Eimeria magna in the nest box. Three doses were t ested, d1 = 4 x 10(2) oocysts, d2 = 4 x 10(3) oocysts, d3 = 4 x 10(4) oocysts, The animals were challenged individually with 10(4) oocysts o f a wild strain of E. magna at 35 days of age, 5 days after weaning. T he oocyst output and weight gain were recorded after vaccination and a fter challenge. The vaccinated animals did not display any vaccine rea ction. The dose d3 was totally effective on oocyst output and on weigh t gain under our experimental conditions. As our challenge conditions were severe, we think that a lower vaccine dose could be used. This me thod proved to be efficient, and quick and easy to use because it did not require animal manipulation.