annual report - Central Institute of Brackishwater Aquaculture

PROGRESS OF RESEARCH
CRUSTACEAN CUI-TURE DI1'ISIOP.j
Development of hatchery technology for
penacid shrimp (CCD/HT/l)
Madras : L. H. Rao (PL), K. Devarajan,
P. Ravichandrm. M. Kathirvel, K. 0.
Joseph, P. S. Sudeesh, C. P. Balasubramanyam
Imelda Joseph, K. Rangeshwaran, S. S.
Mishra and P. S. P. Gupta.
Narakkal : A. Laxminarayana and
S.M. Pillai
Puri : C. P. Rangaswny and S. Srinivasagam
Development of captive broodstock
A captive broodstwk of tip shrimp
Penneuc monodon was successfully dcveloped
under pond conditions at Muttukadu.
Adult 1'. tnonodon of average sim 160 mm /
33 g were stocked in a O.075 ha non-drainable
pond at a density of 0.8 no./m2 and fed with
CIBA pclleted feed initially @ 3%. of total
biomass gradually reduced to I.?%, supplemented
with woked clam mcitl given @ 3%
of total biomass and also gradually reduced
to 1%. An avcrage six (of 200 mm ! 85 g
(femalcs of avcragc sife 204 mm 193 g and
males 195 mm :' 77 g) was attained in 6
months period. 'Ihr pond water salinity \ras
maintained betwecn 20 to 31 ppl by regular
exchange (10-IS(#!) of seawater drawn from
an intertidal borewell.
Induced maturation
The pond-reared broodstock ii8i re
used for conducting induced breedingcxpcrimcnts.
Initial cxpriments with uni1atcr:lIl)
ablated females maintained in I'ItP (:ink\,
with l(J0'X water exchange daily and lctl on
clam 2nd squid meat Q 154 of total biom;lss
supplemented with polychaetcs @ 10% ol
total biomass, have yielded encouraging results.
Viable eggs and naupliiwere prtduced
and the larvae were successfully reared using .
Chaetocem affutis and Anemia nauplii as
larval feeds. 'he rate of survival from nauplii
to PU and from PLY to YL.20 was 41.6% and
50% respectively.
Backyard hatchery technology
Adopting backyard hatchery technology,
hreeding and Iawal rearing trials lor the
seed production of 1'. monodon were iniGated
at Muttukiidu using C. affinis and
Aaemra nauplii as liiwal feeds. At Narakkal,
trials were continued on the improvement of
backyard hatchery technology for the seed
production of 1'. rrulrcu.\.
Quality control tesb for penaeid post-lar
vae
'10 evaluate the quality of seed produced
in the commercial shrimp halcheries,
post-larvae were collected from different
hatcheries and subjected to several quality
control tests which included visual obsewalions
vu., khaviour, colour and activity; microscopic
tests rrz., muscle-gut ratio,
condition of gut, incclmpletc moulting, mus.
cle deformity, broken appendages, number
ol rostra1 spines, bacterial and lungwl infcction,
l'orirceUa 1 %oo~itut~tn~u~n, MIIL' occlusion
bodies etc. and stress tcsts vrz., exposure
to 1(Kl ppm concentr;~tion of formalin and
sudden si~linity decrease (SO%). Aclivc postlarvae
with full gut, no muscle deformity or
broken appndagc~, with muscle gut ri~tio
morc than 4: 1, witbout bacterialllunpal!MHV
inlection and with the ability to
withstitnd stress test5 were considered
grade I larvae suitable for stxking.
Studiesonlong-distancetransportationof
broodstock
Prcliminiiry expcrirncnta werc conducted
on the transportation of broodstwk
ofP. monodon IP. indicus using anaesthetics