**5.1 Materials and methods**

#### **5.1.1 Search for carriers and parasites**

Sixty ewes were sampled from a flock extensively reared in the countryside near Bari. The flock consisted of approximately 250 heterogeneous subjects belonging mainly to TBD tolerant breeds and crossbreds. The presence of TBPs was checked in the blood samples by a PCR-based molecular approach as described above. Most of the sampled animals were found to carry *A. ovis* mixed with other TBPs. Based on the results of the flock survey and the consent given by the breeder, three ewes carrying *A. ovis* and *T. ovis* were selected and purchased. Following the experimental design (table 7) Lina and Zoppina were splenectomized in 2009 while Gilda in 2010, as described in subsection 3.4.
