3.1 Study characteristics and search results
Initially, a total of 1,343 studies related to the terms were identified on databases. All papers used for analysis were published in English language from 2006 onwards. After aplying inclusion criteria, 30 studies were selected to be sistematically reviewed. Figure 1illustrates the searching process, selection and exclusion.
The general and methodological characteristics of the included studies are presented in Table 1 . A total of 561 isolates of T. gondii from 6,356 (Total sample) free-range chickens were analysed for genotyping, revealing 190 genotypes. The results from the literature review were classified based on country and continent (Table 2 ). Out of the retrieved articles, 27, 2, 1, 0 and 0 studies were from America, Africa, Asia, Europe and Oceania, respectively.