ACQUIRED PROTECTION OF THE RABBIT (ORYCTOLAGUS-CUNICULUS) AGAINST COCCIDIOSIS USING A PRECOCIOUS LINE OF EIMERIA-MAGNA, EFFECT OF VACCINE DOSE AND AGE AT VACCINATION

Sucklings were vaccinated orally once at 25, 27 or 29 days of age with a precocious line of Eimeria magna. Each group received two doses var ying from 3.5 x 10(2) to 3.5 x 10(4) oocysts, At 36 days of age, anima ls received a challenge inoculation with 10(4) oocysts of the wild str ain of E. magna, Vaccination reduced oocyst output 10 to 1000 times af ter the challenge inoculation and prevented the decrease in the weight gain observed in non vaccinated challenged animals. When the vaccinat ion was performed more than 9 days before challenge, full protection w as obtained. An individual oral vaccination performed with 3500 oocyst s gave total protection whatever the age at vaccination between 25 and 29 days of age. (C) 1997 Elsevier Science B.V.