Shafiqur Rahman
Freshwater Sub-station, Bangladesh Fisheries Research Institute, Saidpur, Nilphamary-5310, Bangladesh
Maliha Hossain Mou
Freshwater Sub-station, Bangladesh Fisheries Research Institute, Saidpur, Nilphamary-5310, Bangladesh
Md. Shirajum Monir
Head Quarter, Bangladesh Fisheries Research Institute, Mymensingh-2201, Bangladesh
Culture potentials, Heteropneustes fossilis, Stocking densities, Net benefit
Bangladesh fisheries Research Institute, Saidpur, Nilphamari
Animal Health and Management
Description of the study area and duration: The present experiment was carried out in Freshwater Sub-station, Bangladesh Fisheries Research Institute, Saidpur, Nilphamari located at 25o 46'41'' N, 88o 53' 51'' E of Bangladesh for a culture period of seven months during July 2012 to January 2013. Nine experimental mini ponds were undertaken for three treatments each with three replicates. The average area of the ponds was 0.006 ha with depth of 1.18- to 1.21 m. Pond preparation: Prior to stocking, the experimental ponds were dried and cleaned for unwanted weeds and species. The dried ponds were exposed to sunlight for several days and then liming the bottom soil (@ 250 kg/ha of Ca2O) and enclosed by fine nylon mosquito net. After five days, ponds were filled up with underground water and fertilized with cow dung at the rate of 100 kg/ha and waited for a week to allow the water become suitable for stocking. Sources and stocking of Shing fingerlings: The fingerlings of Shing (H. fossilis) used in this experiment were produced in the hatchery of Freshwater Sub-station, Bangladesh Fisheries Research Institute, Saidpur, Nilphamari. Fingerlings of Shing (H. fossilis) were stocked at the rate of 1,85,000, 2,00,000 and 2,25,000 individuals/ha under treatment-1 (T1), treatment-2 (T2) and treatment-3 (T3), respectively on 01 July 2012. Before stocking the initial mean weights of the fingerlings were measured using sensitive balance (OHAUS Model CS-2000). Feed supply: After stocking, in order to meet up the increasing dietary demand, in all the treatments, a 35% protein containing floating pelleted feed (MEGA feed) were applied at the rate of 12-4% of estimated fish biomass twice daily at 6.00 hr in the morning and at 19.00 hr in the late afternoon. The fingerlings were fed at the rate of 12% of their body weight for the first month and it was reduced to 4% on the subsequent months. During the culture trial, in every month all the experimental ponds were applied lime and salt at the rate of 125 and 74 kg/ha, respectively. Growth measurement: The growth of experimental Shing (H. fossilis) was observed fortnightly for each pond random sampling method. At least 50 fishes were sampled with the help of a cast net to measure the growth to assess the health status and for feed adjustment. Physico-chemicals properties: Physico-chemicals parameters such as surface water temperature (oC), water depth (cm), transparency (cm), dissolved oxygen (mg/l), pH and ammonia (mg/l) was measured fortnightly using a Celsius thermometer, a graduated pole, a Secchi-disk a portable dissolved oxygen meter (HI 9142, Hanna Instruments, Portugal) and a portable pH meter (HI 8424, Hanna Instruments, Portugal) and a portable amonia test kit (Hanna), respectively. Total alkalinity was determined following the titrimetric method according to the standard procedure and methods. Harvesting of fish: After seven months of rearing, the fish were harvested by dewatering the ponds. During harvested, at least 100 fish were counted and individually weighted from every treatments to assess growth, survival, FCR and production. Specific growth rate (SGR %day) and feed utilization efficiency were calculated. Data analysis: The mean values for water quality parameters, growth, survival, FCR, production were tested using one-way analysis of variance (ANOVA), followed by testing of pair-wise differences using Duncan’s Multiple Range Test. Significance was assigned at the 5% level. All statistical analysis was done by using the SPSS (Statistical Package for Social Science) version-21.5.
Trends in Fisheries Research Volume 3, Issue 2, 11-16 (2014) ISSN: 2319–474X (p); 2319–4758 (e)
Journal