Response to bidirectional selection for naupliar length in Artemia
franciscana
M.M.
Shirdhankar, P.C. Thomas-2003
Aquaculture
Research, 34(7): 535-541
Abstract:
Bidirectional
mass selection for naupliar length was practised in Artemia franciscana
from Great Salt Lake, UT, USA, with the aim of developing two divergent
lines, namely small naupliar size (SNS) and bigger naupliar size (BNS). A
random-bred control line was also maintained to quantify the environmental
effects. The mean naupliar length in the base population was 486.99±2.11 µm
in males and 490.58±1.82 µm in females. Six generations of selection
for smaller naupliar size in the SNS line resulted in a phenotypic response
of -45.32 µm and -37.52µm decreases in naupliar size in males and females respectively. In the BNS
line, responses (increase in size) from five generations of selection for
bigger size were 8.59 µm and 35.80 µm respectively. The
cumulative genetic gain in males and females of the SNS were -41.72 µm
and -38.76 µm compared with 12.64 µm and 39.48 µm,
respectively, in the BNS line.
(College of Fisheries, Shirgaon Ratnagiri,
Maharashtra, India, 415 629. E-mail: mangeshshirdhankar@yahoo.com)