Publication Date:
2021-07-15
Description:
Application of genetic manipulation techniques on cultured fish have been employed in developed economies to increase food fish yield. In this study, a simple and safe biotechnology genetic manipulation technique was applied to produce triploid African giant catfish (Clarias gariepiirus Burchell 1822) larvae .Eggs numbering 100~c10 in quadruplicates from C. gariepinus were activated by milt from the same species and were subsequently transferred to a thermoregulated refrigerator maintained at 2degreesC for 20 min to suppress cell division, starting at 4 min after activation. Haploid larvae were produced by activating eggs with UV irradiated milt at 30000 uWcm-2 for 15 min. Fertility, hatchability and survival after one week for triploids were 82.5%, 69.8% and 61.3% against haploid and diploid controls, 100%, 15%, 0% and 100%,93%, 91 % (p 〈 0.05) respectively. Ploidy levels of the embryos cytogenetically were evaluated in day-old posthatched embryos incubated in 0.02% colchicine for 2-4 h. Head and yolk sac were discarded in 0.9% NaCl while remaining fragments were later treated with hypotonic solutions of distilled water for 5 min, and subsequently with diluted catfish serum 1: 4 for 25 min. Cells were fixed with 1:3 acetic acid ethanol mixture. Slide with the chromosome spreads were then stained with 20% Giemsa in phosphate buffered solution. Chromosome numbers obtained were 28~c2, 56~c2, and 75~c2 for haploid control, diploid control and triploid treatments respectively. Using a simple biotechnology technique as above, triploid C. gariepinus larvae were produced in the present study. The potential application on food fish security of triploid catfish in aquaculture especially in Nigeria is discussed.
Description:
Includes: 1 table and 1 plate.;Also includes: 20 refs.
Keywords:
Aquaculture
;
Clarias gariepinus
;
Nigeria
;
Biotechnology
;
Clarias gariepinus
;
Chromosomes
;
Aquaculture
;
freshwater environment
;
Genetics
;
Cultured organisms
;
Food fish
;
Yield
;
Biotechnology
;
Fertility
;
Hatching
;
Sustainable development
;
Aquaculture
;
Aquaculture development
;
Appropriate technology
Repository Name:
AquaDocs
Type:
conference_item
,
TRUE
Format:
application/pdf
Format:
application/pdf
Format:
117-122
