AVA ICMBio-MMA

Silvano García1,3, George S. Yasui2, Jurandir J. Bernardes-Júnior1, Bruno Corrêa da Silva3 Hilton Amaral-Júnior3 & Evoy Zaniboni-Filho1

1Programa de Pós-Graduação em Aquicultura, Centro de Ciências Agrárias

Departamento de Aquicultura, Universidade Federal de Santa Catarina, Florianópolis, Brasil

2Laboratório de Teriogenologia, Faculdade de Zootecnia e Engenharia de Alimentos

Universidade de São Paulo, Pirassununga, Brasil

3Campo Experimental de Piscicultura de Camboriú, Empresa de Pesquisa Agropecuária e

Extensão Rural de Santa Catarina, Camboriú, Brasil

Corresponding author: Bruno Corrêa da Silva (brunosilva@epagri.sc.gov.br)

ABSTRACT. This study evaluated sequential double-temperature shock (heat and cold) to induce triploidy in Rhamdia quelen. Fertilized eggs were heat shocked at 37, 39 and 41°C at 2 min post-fertilization and then cold shocked at 1°C for 20 min. Intact eggs were used as controls. Egg viability in control groups was higher (65.5 ± 37.0%) than that at 37°C (58.2 ± 37.7%), 39°C (1.8 ± 0.3%) and 41ºC (0%). The survival of control hatchery (64.6 ± 36.8%) was higher compared to treatments at 37ºC (24.4 ± 15.5%) and 39ºC (0.6 ± 0.07%). Triploid percentages were 98.5% at 37°C and 100% at 39°C. Therefore, while double-temperature shock induced 100% triploidy in R. quelen, it also significantly decreased embryo survival and increased the deformity larvae.

Keywords: Rhamdia quelen, silver catfish, polyploidy, temperature shock, flow cytometry.