Morphological comparison of wild, farmed and hybrids of two South American silversides, Odontesthes bonariensis and Odontesthes hatcheri

HATTORI, R.S.; STRÜSSMANN, C.A.; CRICHIGNO, S.A.; CUSSAC, V.

AQUACULTURE RESEARCH

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2016 vol. 47 p. 1797 - 1808

1355-557X

In the present study, body shape of hybrid and presumptive introgressed South American silversides was studied. Body shape of O. bonariensis and O. hatcheri from wild populations and farmed stocks was compared in order to provide basic information on the effects of fish farming on morphometric parameters. Subsequently, wild presumptive introgressed individuals and artificially hybridized farmed individuals were morphologically analyzed to assess the effects of hybridization on the same parameters. Most farmed purebred individuals were shorter and higher than their wild counterparts, which is probably due to the favorable conditions for growth compared to the wild habitat. However, the results evidenced that purebred individuals were more slender than both hybrid (farmed) fish and introgressed (wild) fish. Further studies about the growth performance of hybrid Odontesthes will be needed in order to assess if the combination of hybridization and sterilization could produce, under farming conditions, growth performances according to the requirements of aquaculture These results suggest that introgressed individuals may present higher fitness compared to the pure species, not only in captivity, but also in the wild. Thus, hybrid and introgressed fish may comprise both a benefit for fish culture and risk for natural environments with sympatric pejerrey populations.