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Articles
by
M. Aminur Rahman |
Total Records (
10 ) for
M. Aminur Rahman |
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S. M. N. Amin
,
Aziz Arshad
,
Siti Shapor Siraj
,
B. Japar Sidik
and
M. Aminur Rahman
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Reproductive cycle, growth, mortality and exploitation rate of Acetes indicus
were examined in the coastal waters of Malacca, Malaysia between February 2005
and March 2007. Monthly length frequency data were analyzed using FiSAT software
for estimating population parameters of A. indicus, including asymptotic
length (L∝),
growth co-efficient (K) and exploitation rate (E) to assess the status of the
stock. The annual mean L∝
and K for males were estimated at 29.93 mm and 1.60 yr-1,
and for the females were 40.95 mm and 1.20 yr-1. Mean growth
performance index (φ`) was calculated as 3.15 and 3.31 for males and females, respectively.
Maximum life span (tmax) of males and females was 1.88 and 2.50 years.
Total mortality (Z) by length converted catch curve was estimated at 4.30 yr-1
for males and 3.62 yr-1 for females. The rate of natural mortality
(M) for males and females was calculated as 2.54 yr-1 and 1.93 yr-1,
and the fishing mortality (F) was 1.77 yr-1 for males and 1.70 yr-1
for females. Recruitment pattern of A. indicus was continuous throughout
the year with two major peaks. The exploitation rate (E) of males was 0.41 and
that of females was 0.47, though the exploitation rates were slightly less than
the optimum level of exploitation (E = 0.50). Thus, the stock of A. indicus
is under pressure in the coastal waters of Malacca, Malaysia. |
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B.I. Usman
,
S.M.N. Amin
,
A. Arshad
and
M. Aminur Rahman
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Plotosus canius, the grey-eel catfish belonging to the family Plotosidae is endemic to the south-east Asia and Australia. Primarily the fish is found in marine environment but at times may be found in brackish or fresh water environments. Despite the vast research that have been conducted on various catfish species, both marine and freshwater; little attention has been paid to P. canius. This study reviewed published information on the distribution, biology and fisheries of this economically important fish species. |
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M. Aminur Rahman
,
Fatimah Md. Yusoff
,
A. Arshad
,
S.M.N. Amin
and
Mariana Nor Shamsudin
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An attempt was undertaken to describe the size frequency distribution, length weight relationships and fecundity estimates of short-spined sea urchin, Salmacis sphaeroides from Peninsular Malaysia. In total 355 specimens of S. sphaeroides were collected from the inter-tidal shoal of Tanjung Kupang, Johor during the breeding season in March-August 2011. For each individual, the Total Length (TL) was measured using digital slide calipers and individual Body Weight (BW) was also taken through a digital balance. Mean length of S. sphaeroides was estimated as 72.85 mm and the mean weight was 143.01 g. Among the 355 specimens measured, 158 were males and 197 were females, indicating a sex ratio of 1 male to 1 female (1:1.25). The logarithmic form of length-weight relationship of S. sphaeroides was LogW = 2.4396xLogTL-2.3958. The exponential form of equation obtained for the length-weight relation was W = 0.004xTL2.4396. The value of regression co-efficient (R2) estimated for the species was 0.77. The mean fecundity was estimated at 7,676,000 (±247773) eggs. The regression coefficient between the absolute Fecundity (F) and Total Length (TL) was 0.76 and between the fecundity and drained body weight (DW) was 0.89; revealed linear regression model with a positive and significant relationship. This study represents the first time results on the total length-body weight relationships and fecundity estimates of this sea urchin from Peninsular Malaysia. The findings would immensely be helpful towards the understanding of growth patterns and fecundity, which will ultimately facilitate to develop the breeding, larval rearing and aquaculture of sea urchins. |
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M.Z. Hazmadi
,
S.M.N. Amin
,
A. Arshad
,
M. Aminur Rahman
and
S.M. Al-Barwani
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Study on length-weight relationships of anchovy, Stolephorus tri collected from Benting Lintang (Lat. 5°44'33.62 N and Long. 102°39'22.84 E), the coastal waters of Besut, Terengganu was carried out on June and July 2010. Stolephorus tri are important component of marine ecosystems and commercially significant marine food resources in Malaysia. The mean size length of Stolephorus tri was 63.53 mm with a range of 51.0-76.0 mm. The average weight of Stolephorus tri was 1.57 g. The relationship between total length and body weight of Stolephorus tri was Log W = 3.0384 Log TL-5.2923 (W = 0.00001 TL3.0384). It is revealed that the exponent b for Stolephorus tri was very close to the isometric value (b = 3). Therefore, the relative growth of Stolephorus tri was isometric in the coastal waters of Besut, Terengganu. |
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Amani. A.A
,
S.M.N. Amin
,
A. Arshad
and
M. Aminur Rahman
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Population parameters of male and female A. japonicus were studied using the monthly length frequency data to evaluate the mortality rates and its exploitation level. The sex ratio (male: Female) was found at 1: 0.94. Asymptotic length (L∞) was 25.20 mm and 28.88 mm for male and female, respectively. Growth co-efficient (K) for males and females was estimated at 1.80 and 1.30 year-1, respectively. Total mortality (Z) was calculated at 5.98 and 4.44 year-1 for male and female of A. japonicus respectively. Natural mortality (M) was 2.82 and 2.19 year-1 for the male and female shrimps. The fishing mortality (F) was 3.16 year-1 for male and 2.25 year-1 for female. Exploitation level (E) for male and female of A. japonicus was calculated at 0.53 and 0.51. The exploitation level was slightly over (E>0.50) the optimum level of exploitation (p = 0.50). The stock of A. japonicus was found to be slightly over exploited in Tanjung Dawai estuarine waters. |
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M. Aminur Rahman
and
Tsuyoshi Uehara
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Experiments on backcrosses using the gametes of the reciprocal F1 hybids and the
conspecific controls of the two sympatric species of tropical sea urchins, Echinometra
sp. A (Ea) and Echinometra sp. C (Ec) were conducted in the laboratory. The ova from
the female hybrid of Ea x Ec and Ec x Ea yielded a higher percent of fertilization with
Ea x Ea sperm than with Ec x Ec sperms. Conversely backcrosses by hybrid males of
either crosses yielded a higher percentage of fertilization with Ec x Ec ova than with Ea
x Ea ova, indicating that Ea ova appeared to be more descriminating than Ec ova due to
the sequence differences in their gamete recognition alleles. On the other hand, the higher
fertilization rates between the same types of hybrids versus the different types of hybrids
indicated the presence of a complex sorting of gamete compatibility genes. However, the
higher fertilization rates as well as higher survival rates of larvae, juveniles and adults
of the F2 hybrids eliminates the possibility that hybrid inviability/sterility is a postzygotic
mechanism of reproductive isolation. In adults, EaEa x EaEc and EaEa x EcEa juveniles
were consistantly larger than those of equivalent ages of the other crosses in terms of
relative test dimesions and growth performances; largest to smallest were EaEa x EcEa,
EaEa x EaEc, EcEa x EaEa, EaEc x EaEa, EcEa x EcEc, EcEa x EcEc, EaEc x EcEc,
EcEc x EcEa and EcEc x EaEc, respectively. These results of growth performances
however, indicated that the F2 hybrids were viable in the lab-reared conditions. This
experiment represents the first successful production of F2 hybrids (Progeny of
backcrosses) in the laboratory. Although, coloration patterns of F2 hybrids tended to be
maternal, other characters such as test sizes and spine lengths, growth performances and
phenotypic characteristics (such as tubefoot and gonad spicules, pedicellaria valve length
and gamete sizes) tended to be intermediate but closer to their maternal F1. Despite these
findings, hybrids with these morphological characters were not found in the field,
indicating possible prezygotic isolating mechanism(s) that either singlely or
incombination with others creating barriers to hybridize in the field. The results of this
study further indicate that considerable morphological and genetic integrity is maitained
between Echinometra sp. A (Ea) and Echinometra sp. C (Ec) which strongly supports
their recognition as distinct evolutionary species despite the fact that they produce F1
and F2 hybrids under laboratory conditions. |
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M. Aminur Rahman
,
S. Ahammed
,
K.M.M. Hasan
,
M.M.H. Bhuiyan
,
F. Ali
,
M.S. Islam
and
M.M. Rahman
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A study was undertaken to develop the economic status of rural women of Kishoregonj district in Bangladesh through fish farming. In total, 200 beneficiaries of Nari Uddug Kendra (NUK) having various sizes of pond were selected by baseline survey at Pakundia, Hossainpur and Tarail Upazillas (sub-districts) of Kishoreganj district and made a two-day training on carp-prawn polyculture and provided counseling on the pond sites in a small group routinely from pond preparation to marketing of their products. Five fish species viz., silver carp (Hypophthalmichthys molitrix), catla (Catla catla) rohu (Labeo rohita), grass carp (Ctenopharingodon idela) and Thai sharpunti (Barbodes gonionotus) and one prawn species, golda (Machrobranchium rosenbergi) were used in the present investigation. Pond preparation and management were depended upon the use of lime, cow dung, urea and Triple Super Phosphate (TSP). The average stocking densities of fish fingerlings and shrimp post-larvae (PL) were 17,290 ha-1 with the species compositions of silver carp (20%), catla (10%), rohu (20%), grass carp (1.43%), Thai sharputi (14.3%) and golda (34.3%). Supplementary feed comprising of rice/wheat bran and mustard oilcake (2:3) was applied at the rate of 8-12% of the total live fish weight twice daily. Duckweed either produced in pond or collected from the external sources was also used as additional supplementary feed. Physico-chemical parameters of pond water were within the normal range for fish culture. Mean production of fish and shrimp was obtained to be 1,980 kg ha-1 over an average culture period of 240 days. Pond management input and cost-benefit data were recorded by the farmers and were then analyzed by fish experts. The mean production cost was estimated to be Tk. 18,772 ha-1 with a benefit of Tk. 47,041 ha-1. |
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M. Aminur Rahman
,
M. Kamruzzaman Hossain
,
M. Abul Kalam Azad
,
M. Kamruzzaman
,
Harun-Ar-Rashid
,
M. Mosfikur Rahman
and
K.M.M. Hasan
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Thai sharpunti, Barbodes gonionotus (Bleeker) was cultured with major carps viz., rohu (Labeo rohita), catla (Catla catla), mrigal (Cirrhinus mrigala) and silver carp (Hypophthalmichthys molitrix) in seasonal ponds over a period of 90 days. Three treatments differing in stocking densities were tested with three replicates each. The stocking density of rohu, catla, mrigal and silver carp fingerlings in all the experimental ponds was 494, 94, ,482 and 1,235 ha-1, respectively. In addition, Thai sharpunti fingerlings was stocked at the rate of 9.880, 4.820 and 19.760 ha-1 in T1, T2 and T3, respectively. All the fishes were fed with supplementary diet comprising of rice bran and mustard oil cake (1:1) at the rate of 6-7% of the estimated body weight twice daily. Physico-chemical parameters and plankton populations of pond water were taken every fifteen days interval and were within the normal range for fish culture. The total production of fish at the end of the experimental period was 1,248.34, ,343.19 and 1,592.67 kg ha-1 in T1, T2 and T3, respectively. Significantly higher (p<0.05) production of fish was obtained in T3 due to higher number of Thai sharpunti. Despite this, consistently higher individual weight gain of rohu, catla, silver carp and Thai sharpunti was observed in T1 than in T2 and T3. Other growth performances (final weight and specific growth rate) and survival of fish also followed the similar trends as weight gain. Considering the highest individual growth and survival of fish, the stocking density of Thai sharpunti in T1 may be recommended for culture with Indian major carps in seasonal ponds to attain quick marketable size and to avoid disease risk. |
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M. Hazmadi Zakaria
,
S.M.N. Amin
,
M. Aminur Rahman
,
A. Arshad
,
A. Christianus
and
S.S. Siraj
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The freshwater fish, Probarbus jullieni (Sauvage), locally referred to as Temoleh, is a high-valued freshwater fish in Malaysia and has both cultural and conservational significance. It is widely distributed in the North-east Asian countries such as Thailand, Cambodia, Vietnam and Malaysia. During the recent past, the natural stocks of P. jullieni have been decreased severely due to habitat degradation and man-induced hazards in aquatic ecosystem. Despite the vast research that has been conducted on various carp species, little attention has been given to P. jullieni. This study reviewed the published information on the status, distribution, reproduction and biodiversity of this commercially important fish species. The findings would greatly be helpful towards the species conservation and aquaculture development of the highly endangered P. jullieni. |
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M. Aminur Rahman
,
Tsuyoshi Uehara
and
S. Mustafizur Rahman
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The effects of egg size on fertilization, fecundity, embryonic and larval development as well as offspring performance were compared between two closely related species of tropical sea urchins, Echinometra sp. A (Ea) and Echinometra sp. C (Ec) through laboratory experiments. Ec had significantly larger gametes in terms of egg diameter, egg volume and sperm head length and produced significantly larger but fewer eggs with higher fertilization rate than Ea. Developmental time from fertilization to the formation of echinus rudiment, just prior to the metamorphic competence of Ea were significantly longer than Ec, suggesting that increased allocation to energy reserves in larger Ec eggs reduced the development period as compared with the small Ea eggs. Consequently, smaller eggs of Ea produced smaller larvae than Ec throughout the larval period, due to the small amount of maternal investment as stored nutrients. As Ea and Ec have diverged from their ancestral species, the differences of the above traits related to egg sizes transcended species differences between Ea and Ec. |
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