First Report on Successful Triploidy Induction in Clarias gariepinus (Burchell, 1822) Using Electroporation

Victor Tosin Okomoda,Ambok Bolong Abol-Munafi,Chukwuemeka Onwuka Martins,Joshua A Umaru,Sheriff Md Shahreza,Lubna Aminath,Anuar Hassan,Sunday Abraham Oladimeji,Mhd Ikhwanuddin,Alabi Isaiah Korede

doi:10.1038/s41598-020-59389-2

Abstract

This study investigated the use of electric-shock in inducing triploidy in African catfish Clarias gariepinus. To achieve this, three voltages (9, 12, 21 V) were applied for different durations (3, 5, 10 min). The shock was initiated approximately three minutes after fertilization followed by incubation in ambient temperature. After incubation, hatchability and survival rates were determined while ploidy status of the treatment fishes was confirmed in one-month-old fingerlings using the exclusive triploid range of the erythrocyte major axis previously reported for the same species (11.9–14.9 μm) and by cytogenetic analysis of the chromosome. The results showed triploidy were achieved in 10 to 85% of the treatment groups. A consistent trend of decrease in hatchability and an increase in triploidy rate was observed with increased electroporation voltages and shock durations. The mean erythrocyte major axis length of triploid progenies (3n = 84) was observed to be between 11.3–14.6 μm and was higher than the range of 7.0–10.5 μm recorded for diploid progenies (2n = 56). It was concluded that electric shock can be used to induce triploidy in African catfish C. gariepinus.

Highlights

Aquaculture growth is predicated on the need to feed an ever-growing population, the development and application of modern biotechnological tools to improve production characteristics of fishes
Artificial chromosome manipulation techniques were at first developed with amphibians[10] but later proved to be well suited for other aquatic organisms[11]
This study is aimed at determining the possibility of triploidy induction in African catfish C. gariepinus using different electric voltages and shock duration

Summary

Introduction

Aquaculture growth is predicated on the need to feed an ever-growing population, the development and application of modern biotechnological tools to improve production characteristics of fishes. The time window in which triploidy can be induced (i.e. the extrusion of the second polar body) as reported in many previous studies has been given to be between 3 to 4 min post-fertilization. This study is aimed at determining the possibility of triploidy induction in African catfish C. gariepinus using different electric voltages and shock duration.

Results

Conclusion