Triploidy induction in tambaqui (Colossoma macropomum) using thermal shock: fertilization, survival and growth performance from early larval to the juvenile stage

ABSTRACT

This study assessed the effectiveness of double thermal shock to induce triploidy in tambaqui (Colossoma macropomum) and compared the fertilization, survival, and growth performance of diploid and triploid fish. Freshly fertilized eggs were subjected to heat shock (40 or 42°C) for 2 min and, after that, a cold shock (4°C) for 25 min. Eggs that were not exposed to the heat/cold shock were used as control. Ploidy was assessed by flow cytometry. Larvae (21 days after hatching) treated with thermal shocks displayed reduced fertilization and survival rates. The larvae in the 40/4°C and 42/4°C groups displayed higher growth than the control group. The juveniles (135 days after hatching) in the 42/4°C group showed higher growth than the other groups. The 42/4°C shock induced triploidy in 17.5% of nuclei. The double thermal shock 42/4°C did not induce a high rate of triploidization in tambaqui but produced fish with better growth performance.

KEYWORDS:

• Fertilization rate
• flow cytometry
• growth
• thermal shock
• triploidization

Acknowledgments

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES). We shall also thank Bahia Pesca for the donation of fish.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, upon reasonable request.

Additional information

Funding

This work was supported by the CAPES [1798783].