Page 223 - PARVEEN, S
P. 223
yolk vesicles stage and yolk granules stages in after 8 hours and then to deep grey in all grades
August. In September, the follicular cells of the of formalin preserved fish after 24 hours. The
oogonia were ruptured, shrunk forming irregular cornea became dull within 8 hours and remained
shaped in October. Oogonia were also shrunk with till 16 hours in all grades but, after 24 hours it
thin, irregular shaped structure but broken parts of became opaque. Simultaneously, eyeball became
the ruptured follicular cells were scattered in case settled deep within 4 hours in all percentage of
of M. armatus. Experimental attempts on artificial formalin used. The muscle texture also changed
propagation indicated that both freshwater eels from compact to elastic and soft after 8, 16 and
were difficult to breed using inducing agents like 24 hours of preservation in formalin treated fish.
pituitary glands (PG) of 10, 20, 50,100 and 150 mg The scales were compressed and shiny in ,0.5%
per kg of body weight. Same doses were used for formalin but, altered color in all other grades
both sexes with equal sex-ratio. In both cases, after 8 hours and consequently started to shed
brood fish died at higher doses of injection given at after 24 hours. Thus, formalin negatively
100 and 150 mg PG/kg bodyweight. However, M. affected the morphological and organoleptic
cuchia breed naturally in cisterns when provided indices of P. ticto.
with water hyacinths and tunnel in muddy bottom.
M. cuchi a fed with chopped cooked fish attained a 600 SAHA, N.C. & ISLAM, M.S. (Bangladesh
mean weight of 18.75 ± 2.3 g and cent percent Fisheries Research Institute, Mymensingh). Factors
survival. While in case of M. armatus best growth affecting the adoption of carp polyculture in
by weight (12.0 ± 2.48 g) and cent percent survival Bangladesh. Bang. J. Fish. Res., 2005, 9(1), 81-82.
were achieved using chopped raw fish. Car tyre
was observed as best shelter for attaining the mean A study was conducted to determine the factors
weight gain 22.53 ± 2.24 g and cent percent affecting adoption of pond polyculture in six
survival of M.cuchia. While PVC pipe was found villages of three districts namely Mymensingh,
to be the best shelter for M. armatus, where it Bogra and Narshingdi in Bangladesh. In
attained the mean weight of 12.73 ± 1.88 g and Mymensingh, 75% pond owners adopted carp
cent percent survival. polyculture technology whereas in Bogra and
Narshingdi only 16% and 25% pond owners,
599 RIZVEE, A.S.; NABI, M.R. & respectively adopted this technology for fish
KAMRUJJAMAN, M. (Dept. of Zoology, production. The production of fish per unit area
Jahangirnagar University, Savar, Dhaka). was found to be 5 to 10 times higher in
Morphological and organoleptic changes in Mymensingh compared to that of Bogra and
formalin treated fish, Puntius ticto (Hamilton). Narshingdi. Fish farmers identified three main
Bang. J. Life Sci., 2007, 19(1), 17-24. problems affecting the adoption of pond
polyculture viz. lack of input used in aquaculture,
Present study showed that the body color of low fish yield and lack of credit facilities for pond
formalin preserved Puntius ticto turned to grey polyculture. The technological awareness of the
in 0.5%, 1% and 1.5% formalin, while dull in farmers directly contributed towards use of inputs
2% and 2.5% formalin after 8 hours of the in culture ponds. The positive impact of
preservation. This grey color formed by up to technological dissemination found on input use,
1.5% formalin also changed to dull after 24 fish yield and uplifted socioeconomic condition.
hours. Gill color first changed from red to grey
216
