Experimental
susceptibility of different life-stages of the giant freshwater prawn, Macrobrachium
rosenbergii (de Man), to white spot syndrome virus (WSSV)
R.B. Pramod Kiran, K.V. Rajendran, S.J.
Jung, M.J. Oh-2002
Journal of Fish
Diseases, 25(4):
201-208
Abstract:
Studies were conducted by
injecting/feeding white spot syndrome virus (WSSV) derived from infected
shrimp, Penaeus monodon (Fabricius), to different life-stages, namely
post-larvae, juveniles, sub-adults and adults of Macrobrachium
rosenbergii (de Man). The disease was also induced in brood stock, and
the eggs and larvae derived from these animals were subsequently tested for
WSSV infection. All the stages except egg used for the experiment were found
WSSV positive in histopathology, cross infection bioassay and polymerase
chain reaction (PCR) analysis. Experimentally infected post-larvae and
juveniles showed a high percentage of mortality and an increased rate of
cannibalism. The cumulative mortality in post-larvae was up to 28%; with
28-40% cannibalism resulting in a maximum loss of up to 68%. In juveniles,
observed mortality and cannibalism were 10-20% and 6.7-30.0%, respectively,
and the maximum loss recorded was 50%. In sub-adults, mortality ranged from
2.8 to 6.7%, cannibalism was up to 20% and the total loss was up to 26.7%.
Sub-adults and adults were found to be more tolerant to the infection as
evidenced by the mortality pattern. A nested (two-step) PCR resulted in a
570-bp product specific to WSSV in all stages, except the eggs.
(Central Institute of Fisheries
Education, J.P. Road, Versova, Andheri (W), Mumbai -400 061,
India, e-mail of K V Rajendran: rajendrankv@hotmail.com)