GENETIC AND MORPHOLOGICAL CHARACTERIZATION OF WILD AND CULTURED SPECIES OF CLARIAS SCOPOLI, 1777 AND HETEROBRANCHUS GEOFFROY SAINT-HILAIRE, 1808
GENETIC AND MORPHOLOGICAL CHARACTERIZATION OF WILD AND CULTURED SPECIES OF CLARIAS SCOPOLI, 1777 AND HETEROBRANCHUS GEOFFROY SAINT-HILAIRE, 1808
No Thumbnail Available
Date
2014-02
Authors
YASHIM, ESTHER YOGBABALIAT
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Genetic and morphological studies on wild and cultured species of Clarias and Heterobranchus were conducted from August 2012 to January 2013. A total of forty (40) specimens comprising Clarias gariepinus (10), C. anguillaris (5), C. galmaensis (5), Heterobranchus bidorsalis (5), H. longifilis (10) and H. isopterus (5) were obtained from River Galma, Zaria and Bagoma Reservoir Birnin Gwari (wild), Miracle Fish Farm, Zaria and National Institute for Freshwater Fisheries Research (NIFFR), New Bussa (cultured). Morphometric data for each fish sampled were taken following Teugels (1986a) and the physico-chemical parameters of the habitats from which the fishes were collected were also determined. A total of eighty (80) samples of muscle and fin tissue of fish were obtained and preserved at -20°C for molecular analysis. DNA was extracted from the tissues using genomic Quick-gDNA™ MiniPrep (50 Preps) w/ Zymo-Spin IIN Columns DNA extraction kits. The cytochrome b gene was amplified and a portion of mtDNA containing the gene was amplified as described by Briolay et al. (1998). Restriction digest of the PCR-products was conducted. All products were separated, purified and visualized under ultra violet light and documented. The morphometrics showed that Clarias gariepinus (22.8-43.8cm) and Heterobranchus longifilis (26.3-39.8cm) had the largest sizes range (total length) followed by Clarias anguillaris (17.8-39.0cm) and Heterobranchus bidorsalis (21.7-38.5cm). The smallest in size were Heterobranchus isopterus (18.4-25.6cm) and Clarias galmaensis (15.7-20.5cm) from all the habitats, the same trend was also observed in other morphometric characters although there were some slight variations. Electrical conductivity (230+16.97μS), Total Dissolved Solids (114.25+8.84ppm) and alkalinity (6.2+1.50) had
higher values in the culture environment while lower values (59+11.0 μS, 29+5.0 ppm and 2.05+0.65 respectively) were obtained in the wild. Higher values were observed in Biochemical Oxygen Demand (4.38+2.09mg/L), Dissolved Oxygen (7.7+1.41mg/L) and PO4-P (0.38+0.14mg/L) in the wild habitat whereas lower values were observed in the culture environment. Little variations were observed in pH, temperature, hardness and NO3-N for both wild and culture environments, which were within acceptable limits for fish production. The marked positive correlation(r<0.9) in morphometrics and physico-chemical parameters showed interaction between them. Significant differences (P<0.05) in morphometrics and physico-chemical parameters were observed. Amplification of cytochrome b gene in both fin and muscle tissues of the fish species was successful. Although genetic variation was observed between wild and cultured species, there is a close relationship between them, confirming that they are members of the same family, Clariidae, with good prospects for culture.
Description
A THESIS SUBMITTED TO THE SCHOOL OF POSTGRADUATE STUDIES, AHMADU BELLO UNIVERSITY, ZARIA, IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF MASTER OF SCIENCE (M.Sc.) DEGREE IN BIOLOGY DEPARTMENT OF BIOLOGICAL SCIENCES AHMADU BELLO UNIVERSITY, ZARIA
FEBRUARY, 2014
Keywords
GENETIC,, MORPHOLOGICAL,, CHARACTERIZATION,, WILD,, CULTURED SPECIES,, CLARIAS SCOPOLI,, HETEROBRANCHUS,, GEOFFROY SAINT-HILAIRE