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Eimeria intestinalis is one of the most pathogenic species of coccidia which causes coceidiosis in rabbits.Live oocyst vaccines with attenuated E.intestinalis are attractive for the control of this wide-spread disease.In this study,we developed a precocious line(EiP132)of E.intestinalis after eight successively passaging and collecting of the first appeared oocysts of parental strain,ZJK strain,in the feces of infected rabbits.The prepatent time of EiP132 was reduced from 204h to 132h.For the pathogenicity and immunogenicity tests,results showed that inoculation with 1×103 and 1×104 oocysts did not cause loss of body weight gain or clinical syndrome.On the contrary,infection with 1×104 original strain caused rabbits body weight gain loss(P<0.05)and slight diarrhea.The oocyst output of animals inoculated with EiP132 oocysts was decreased by about 99.9%(P<0.01).After challenge with 1×105 original strain 14 dpi,the body weight gain of rabbits immunized with original or precocious strain previously was similar with those of the control,and was higher than those of the unimmunized and challenged rabbits(P<0.01);while the oocyst output was lower than those of the unimmunized and challenged rabbits(P<0.01).These results demonstrated that the precocious line EiP132 is low pathogenic but with excellent immunogenicity.