Farzana Hossain
Department of Fisheries, Bangladesh
KM Abdul Halim
Department of Fisheries, Bangladesh
A Baker Siddique
Department of Aquaculture, Bangladesh Agricultural University, Mymensingh, Bangladesh
S Monira Shanta
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh, Bangladesh
M Fazla Rabbi
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh, Bangladesh
Rafiul Islam
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh, Bangladesh
M Rafiqul Azam
Department of Fisheries, Bangladesh
M Rafiqur Rahman
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh, Bangladesh
Polyculture, Stinging catfish, Rohu, Catla, Mrigal, Ponds
Modonpur, Netrokona Sadar, and Netrokona
Animal Health and Management
The experiment was conducted in farmer’s pond under semi-intensive rearing system in Modonpur, Netrokona Sadar, and Netrokona for a period of 5 months from 1 March 2017 to 30 July 2017. A total of six perennial ponds were divided under three treatments i.e. T1, T2 and T3 each having two replicates. The area of each pond was 0.12 ha with an average water depth of 4.5 feet. All the ponds were more or less similar shape, size, basin confirmation and bottom type. The ponds were flood-free rain fed, free from aquatic vegetation and well exposed to sunlight. Each ponds have inlet and outlet to provide water and when needed. After selection, at first broken dikes and holes of all ponds were repaired. After that, all kinds of aquatic vegetation (floating, emergent, submerged and spreading) were removed manually and the branches of all trees on the ponds were trimmed off. The predatory and undesirable fishes were eradicated by netting repeatedly and cleaned by poisoning with rotenone at the rate of 25g/decimal/feet water. Liming was done immediately after poisoning at the rate of 1kg/decimal. Five days after liming, all the ponds were manured with cow dung at the rate of 10 kg/decimal, urea and TSP were used in all of those ponds at the rate of 150 g and 75 g per decimal, respectively. Soon after the appearance of light-plankton bloom, all the ponds were stocked more or less similar weight of stinging catfish (H. fossilis), rohu (L. rohita), catla (C. catla) and mrigal (C. chirrosus). The stocking density of rohu, catla and mrigal was same in all the treatment but various stocking densities were stocked in case of stinging catfish. At the stocking, fingerlings of H. fossilis and Indian major carps were stocked as per experimental design.
For the proper growth of fishes, the commercially available mega fish feed was applied throughout the experimental period @ of 6 to 2% of their body weight. The feeding was adjusted on the basis of monthly sampling of fishes. In each sampling ten fish of each species from each pond were caught by cast net. The weight was taken by ordinary balance. Water quality parameters of pond water were monitored monthly between 09.00 and 10.00 hr. Temperature (°C) and dissolved oxygen (mg/l) were determined directly by a digital water quality analyzer Hanna DO meter (Model-HI 9146, Romania), pH by a digital pH-meter (Milwaukee pH meter, Model-PH55/PH56, USA) and ammonia nitrogen by a UV VIS Spectrophotometer water analysis kit (DR 6000TM, USA). Total alkalinity was estimated following the standard method [13, 14]. To evaluate the fish growth performance weight gain (g), specific growth rate (SGR%/day), food conversion ratio, survival rate (%), individual production and total production were measured after end of the experiment. The following parameters were used to evaluate the growth performance of experimental fishes: Weight gain (g) = Mean final weight (g) - Mean initial weight (g).
After 5 months of culture, all the fishes were harvested by netting repeatedly with seine net from each pond and finally drying the ponds. The fishes were counted and weighed individually. Then the final growth gained by each species was recorded by measuring the weight (g) of individual fish. The species-wise and total production for each treatment was determined by multiplying the average weight (g) gained by the total number of survived fish at the end of the experiment.
Statistical analysis The collected data of the experiment were analyzed by one-way analysis of variance by computer (SPSS package program). Comparison between treatment means was carried out by analysis of variance (ANOVA) followed by Duncan’s Multiple Range Test.
International Journal of Fisheries and Aquatic Studies 2018; 6(6): 37-42
Journal