**5.1.3 Experimental infection**

*A. ovis* was isolated from one of the above splenectomized sheep. Lina was the donor for the 2009 lambs and Gilda for the 2010 lambs. Parasite density was estimated on thin blood film obtained by the buffy coat method and expressed as the percentage of parasitized red blood cells. At the peak of parasitaemia in the donor sheep (36% and 60% of red blood cells parasitized respectively), about 400 ml of blood were obtained and each lamb in the breed groups was inoculated intraperitoneally with 25 ml of infected blood.
