Page 12 - 22-0722 EBOOK

วารสารราชบััณฑิิตยสภา
ปีีที่่� ๔๖ ฉบัับัที่่� ๓ กัันยายน-ธัันวาคม ๒๕๖๔
2 ปลาดุุก : ทรััพยากรัชีีวภาพทรังคุุณคุ่าของไทย

Abstract: Walking Catfishes: A Valuable Biological Resource of Thailand
Professor Dr. Uthairat Na-Nakorn
Associate Fellow of the Academy of Science,
The Royal Society of Thailand
Department of Aquaculture, Faculty of Fisheries,
Kasetsart University, Thailand
Walking catfishes refer to the fish in the genus Clarias. In Thailand, there
are seven species of native walking catfishes, of which only two species, Clarias

macrocephalus (Günther, 1864) and C. aff. batrachus ‘Indochina’ (Linneaus,
1758), have been used for aquaculture. Nowadays, aquaculture production of
walking catfish comprises mainly the hybrid between female C. macrocephalus
and male C. gariepinus (Burchell, 1822), which was introduced from Africa.
Although the annual production of the hybrid exceeds 100,000 tonnes,
aquaculture technology of this commodity has not been improved, particularly,
genetics of the brooder. Scientific evidence showed that genetics of the parental

species additively determined growth of the hybrid. Therefore, the performance
of the hybrid can be improved by using genetically improved strains of
C. macrocephalus and C. gariepinus. To acquire a base population with large
genetic base for a selective breeding program, it is necessary that genetically
diverse wild and hatchery populations be crossed. C. macrocephalus used to
possess high genetic variation and has been identified into three genetic groups.
C. batrachus showed a lower level of genetic variation and comprised two genetic
groups. Likewise, C. gariepinus showed substantial genetic variation which has been
used to establish a base population with sufficient genetic variation. At present,

while the diversity is gradually eroded, these genetic resources are not yet fully
utilized. Therefore, conservation efforts are urgently required while the useful traits
of the conserved populations should be studied to enhance efficient utilization.

Keywords: Clarias macrocephalus, C. aff. batrachus, C. gariepinus, aquaculture,
genetic diversity, genetic improvement, conservation