Quantitative genetic variation for resistance to the parasite Ichthyophthirius multifiliis in the Neotropical fish tambaqui (Colossoma macropomum)

摘要: Abstract Tambaqui (Colossoma macropomum) is the main native fish produced in continental aquaculture from South America. However, its production has been negatively affected by significant economic losses due to frequent outbreaks caused parasite Ichthyophthirius multifiliis. Genetic selection for I. multifiliis resistance may represent a sustainable and effective alternative reduce mortality and, therefore, improve of tambaqui. The estimation genetic parameters needed validate whether can be included improvement programs. aim this study was estimate variance components heritability tambaqui, through experimental challenge 218 individuals eight full-sib families. Survival status (SS), time death (TD) load (PL) presenting clinical signs infestation were recorded cohabitation challenge. total cumulative survival rate varied significantly among families (16 100%) TD ranged 217 254 hours post cohabitation, which indicates presence phenotypic variation related infestation. High values estimated SS (0.46 ± 0.09 0.60 ± 0.18, respectively). differences value not PL. This represents first report on disease against Neotropical species. results presented here suggest that tambaqui improved selective breeding.