Quantitative Analyses for Low Temperature Tolerance in a Synthetic Population of Tambaqui (Colossoma macropomum)

• Grant number: 24/16475-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: December 31, 2025
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Rafael Vilhena Reis Neto
• Grantee: Heloísa Moisés Burini
• Host Institution: Faculdade de Ciências Agrárias. Universidade Estadual Paulista (UNESP). Campus do Vale do Ribeira. Registro , SP, Brazil

Abstract

Using quantitative approaches, we propose to verify the possibility of obtaining genetic gain by selection for traits related to tolerance to low temperatures in a tambaqui population composed of 30 full-sib families. About 30 animals from each family, identified with microchips, will be tested, for 90 days, in 2 batteries of 5 polyethylene tanks with capacity of 500L. One of the batteries will operate in a temperature-controlled (28°C) recirculation system and the second will have a continuous flow of water. During the test period, the tanks will be monitored to record the dead animals, and after 60 days the surviving animals will be weighed and measured. The data collected on days to death and performance, together with the information on the kinship of the individuals provided by the pedigree, will be analyzed according to a bivariate mixed animal model (PBLUP) considering fixed effects (polyethylene boxes, final stocking density and age as covariate) and random effects (additive genetic and common environment - hatchery hapas). Through the analysis model, the genetic values of the animals, the (co)variance components, the genetic parameters (heritabilities and genetic correlations) will be estimated and the existence of the Genotype x Environment interaction will be verified for the characteristics evaluated in the batteries of boxes with and without temperature control.