Performance of tilapia Oreochromis sp from different genetic groups, purebreeding and crossbreding, farmed in cages

• Grant number: 19/18661-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2019
• End date: October 31, 2020
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Rafael Vilhena Reis Neto
• Grantee: João Santos Mingato Neto
• Host Institution: Universidade Estadual Paulista (UNESP). Campus de Registro. Registro , SP, Brazil

Abstract

The objective of the project is to evaluate the performance of two Tilapia strains, GIFT and Red Florida and their hybrids, farmed in cages, by growth curves, color standard and body yields. Diallel cross between the two strains will provide four genetic groups: Group 1 (BGift x @Gift), Group 2 (BRed Florida x @Red Florida); Group 3 (BGift x @Red Florida); and Group 4 (BRed Florida x @Gift). After the reproduction, larviculture and fry stages, 100 animals of each genetic group with an average weight of 25 g will be identified by microchips and stored in a cage (2m x 2m x 1.2m), where they will remain until they reach a average body weight 750g. During this period, biometries will be performed every 45 days, when the fish will be weighed, measured in Standard Length, Head Length, Body Height and Width, and classified into: Dark, Red and Spotted. From animals evaluated, 20 in each group will be stunned, slaughtered and processed to obtain the body yields. Growth curves will be adjusted with the weight and morphometric data collected at each biometrics using the Brody, von Bertalanffy, Gompertz, Richards and Logistic models. The parameters of the chosen model will be compared by genetic group using their respective confidence intervals observing the probability of to assume the same value. For comparison of body yields will be considered in the model the effects of the mating system (purebreedin or crossbreeding) and groups nested to the mating system. With the animal classification data, a graph of frequency distribution by genetic groups will be constructed.