“…The only exceptions were STM and OPO, as well as the wild population. An excess of heterozygotes and negative F IS values have also been found in some other farmed fish species, such as Hyriopsis cumingii (Li et al, 2009) Siluris glanis (Kuciñski, Liszewski, Krzyoek ow, Fopp-Bayat, & Ła z czyñska, 2015) and Perca fluviatilis (Ben Khadher et al, 2016). A number of factors may account for negative F IS values in farmed populations, including a reduced effective population size, differential allele frequencies between males and females, non-random matings, reduced viability of homozygotes and genetic drift (Hara & Sekino, 2007;Shahsavarani & Rahimi-mianji, 2010).…”