Genetic Adaptation of Tambaqui (Colossoma macropomum) to Low Temperatures

• Grant number: 24/03467-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: May 01, 2025
• End date: April 30, 2027
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Rafael Vilhena Reis Neto
• Grantee: John Fredy Gómez Agudelo
• Host Institution: Centro de Aquicultura (CAUNESP). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

We propose to verify the possibility of obtaining genetic gain by selection for traits related to tolerance to low temperatures, by quantitative and molecular approaches, in a tambaqui population composed of 60 full-sib families. About 15 animals from each family, identified with microchips, will be tested, for 60 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. Genotyping of the parents and 20% of the progeny will be performed using a panel of high-density SNPs (30k), while the rest of the animals will be performed using a low-density panel (0.5 - 3k). The parental genotypes will be used as a reference for the imputation of genotypes of the progenies genotyped at low density. Considering only the phenotypic and relationship information of the individuals provided by the pedigree (PBLUP), the genetic values of the animals will be estimated and the existence of the Genotype x Environment interaction will be verified, by genetic parameters estamted, for the traits evaluated in the batteries with and without temperature control. Genomic-wide association analyzes will be performed for measured traits, in each environment separately using the ssGBLUP and wssGBLUP approaches implemented in the BLUPF90 statistical software. The predictions of the genetic values of the animals based on pedigree (PBLUP) versus genomic prediction (GBLUP) will also be compared. (AU)