Page 204 - PARVEEN, S
P. 204
conditions of handling and preservation and four commercial freshwater prawn farms at
producing safe and quality products. The samples Fulpur and Tarakanda upazilas in the district of
kept in ice immediately after catch with head-on Mymensingh. The study included aerobic plate
and head-less condition were found to be count (APC), total coliform count, detection,
acceptable for 6 days and 7 days, respectively. isolation and identification of suspected public
Delaying of icing considerably shortened the shelf- health hazard bacteria and their seasonal
life. The pH value increased from 6.36 lo 8.0 after variation, salt tolerance test, antibiotic sensitivity
10 days in ice. The initial average TVB-N value of test of the isolates and washing effect of
sample increased from below 10 mg 100/g to 25 chlorinated water on the bacterial load in the
++
mg/l00g with the lapse of storage period. The Ca prawn samples. APC in sediment soil and water
ATPase activity in presence of 0.1M KC1 slightly of the farm and gill and hepatopancreas of freshly
decreased at the end of 10 days of ice storage. harvested prawns varied considerably among the
Immediately after harvest, initial aerobic plate farms and between summer and winter season.
6
count (APC) was 2.88 × l0 CFU/g which The range of (coliform count in water, gill and
2
8
gradually increased to 1.12 × l0 CFU/g after 6 hepatopancreas ranged between 6 - 2.8 × 10
2
2
days in ice storage and showed early signs of CPU/ml, 1.2 × 10 - 3.32 × l0 CFU/g and 1.43 ×
2
3
spoilage. Initial bacterial genera in the prawn iced l0 - 3.89 × l0 CFU/g, respectively. No coliform
at 0 hours were comprised of Coryneform was detected in pond sediment sample. Suspected
(22.21%), Bacillus (7.40%), Micrococcus health hazard bacteria isolated and identified from
(11.11%), Achromobacter (48.14%), pond sediment, water, gill and hepatopancreas
Flavobacterium/Cytophaga (7.40%), Pseudomonas included Streptococcus, Bacillus, Escherichia
(3.70%) and Aeromonas (3.70%). During ice coli, Klebsialla, Salmonella, Staphylococcus,
storage Coryneforms and Bacillus were always Pseudomonas and Aeromonas, Bacillus,
dominating along with less prominent ones - Salmonella and Staphylococcus, and were found
Micrococcus, Achromobacter and Flavobacterium. to be highly salt tolerant and capable of growing
Studies were conducted on the stability of at 10% NaCl. The antibiotic discs with different
myofibrillar protein of M. rosenbergii under concentration of antibiotics were used for the
different storage and pH conditions. The influence sensitivity test. The organisms were found to be
++
of a wide range of pH on the remaining Ca most sensitive against Tetracyclin and
ATPase activity of M. rosenbergii muscle Gentamycin).
myofibrils after storage at -20°C for 2 days, at 0°C
for 2 days and at 35°C for 30 minutes 559 KARIM, M. (Bangladesh Shrimp
demonstrated that ATPase activities were lower in Foundation, Dhaka). Production of freshwater
acidic and alkaline pH regions and the activity giant prawn using over-wintered juveniles for
++
remained relatively high. Mg ATPase activities enhancement of farm income and reduction of
++
both in presence and absence of Ca remained rural poverty in Bangladesh. Bang. J. Fish. Res.,
high at neutral pH compared to those of acidic 2005, 9(1), 43-44.
and alkaline region. The solubility of myofibrillar
protein decreased gradually both in acidic and Freshwater giant prawn, Macrobrachium
alkaline pH regions. The study also examined the rosenbergii fry produced during late season can
bacteriological quality of freshly harvested M. not withstand low temperature thus the prawn
rosenbergii, pond sediment and pond water from culture programme during winter is hampered. To
197
