Genetic and phenotypic characterization of Toxoplasma gondii isolates obtained from sheep and Iberian pigs in Spain

  1. Mercedes Fernández Escobar
Supervised by:
  1. Esther Collantes Fernández Director
  2. Rafael Calero Bernal Director
  3. Luis Miguel Ortega Mora Director

Defence university: Universidad Complutense de Madrid

Year of defence: 2021

  1. Gema Álvarez García Chair
  2. María de Pilar Horcajo Iglesias Secretary
  3. Elena Jimenez Ruiz Committee member
  4. David Carmena Jimenez Committee member
  5. Solange Maria Gennari Committee member
  1. Sanidad Animal

Type: Thesis


Toxoplasma gondii is an apicomplexan parasite globally distributed with a heteroxenous life cycle that virtually comprises all homoeothermic animals, including humans, as intermediate hosts and felids as definitive hosts. The zoonotic, abortifacient, and foodborne nature of the parasite makes toxoplasmosis a relevant public and animal health concern worldwide.A comprehensive research effort on T. gondii biology along with the rapid development of molecular techniques suitable for strains genotyping over the last decades, led to the initial description of a widely clonal European and North American T. gondii genetic population dominated by three main clonal genetic types (I, II, and III), in contrast to an extremely diverse South American population. However, the information available from Europe is limited, with frequent methodological deficiencies and important sampling disparities among regions. Briefly, the available European literature evidences a clear predominance of type II strains (comprising around 80% of samples) coexisting with much less abundant type III and recombinant strains or mixed infections, as well as minor proportions of type I and imported genotypes. In the specific case of Spain, the majority of the scarce investigations dealt with direct genotyping from clinical samples, with the subsequent limitations to classify the strains and the impossibility of extending its characterization...