Enrichment of rotifer Brachionus rotundiformis with calcium

Possibility of enrichment of rotifer (Brachionus rotondiformis) with calcium (Ca) for feeding the fish fry was investigated. Rotifer was kept for 24 h with aeration in normal seawater (Treatment 1), seawater with 400 mg/l supplemental Ca from Ca-lactate (Treatment 2) and seawater with 400 mg/l supplemental Ca from Ca-chloride (Treatment 3). After the experimental period, Ca contents of rotifer were 0.20, 0.29 and 0.39% of dry weight in T-1, T-2 and T-3, respectively. Ca content of media did not affect phosphorus, zinc and manganese contents of rotifer. Results revealed that rotifer can be enriched with Ca for feeding fish fry and Ca-chloride might be a better source for Ca enrichment

Integration of aquaculture into the farming systems of the floodprone ecosystems of Bangladesh: an evaluation of adoption and impact

This report presents the results of studies undertaken for incorporating low-external input aquaculture practices into the farming systems of a complex floodprone ecosystem in Bangladesh and the impacts of integration on income, nutrition and resource use in rural households. The study shows that multi-purpose ponds which were underutilized or unutilized because of risk of flooding could be made productive through proper management and incorporation into the existing farming systems. Farmers with minimal external inputs were able to increase fish production and consumption by 5 to 8 times.Integrated farming, Farming systems, Technology transfer, Fish culture, Impact assessment, Bangladesh,

Short communication: Culture of Chlorella ellipsoidea in different inexpensive medium and used as food for production of rotifer, Brachionus calyciflorus

Rotifers are multicellular animals with body cavities that are partially lined by mesoderm. These organisms are valuable live food for larval fish and crustacean culture. Several characteristics of rotifers, including their nutritional quality, body size and relatively slow motility have contributed to their usefulness as good prey for active larvae. In general, rotifers have both nutrient content and a high rate of daily production. ... In the present study, we cultured Chlorella ellipsoidea in different media and used as food in powdered and fresh live form along with Backer’s yeast to mass production of rotifers

Size related feeding patterns and electivity indices of silver barb (Barbodes gonionotus Bleeker) from a pond, Bangladesh

The feeding patterns with respect to quality and quantity of food of silver barb, Barbodes gonionotus varied with their size and development. The results indicated that the fish in the size group I (7-25 mm TL) were fairly omnivore with particular liking for rotifera, green and blue-green algae while the size group II (25.1-44 mm TL) and III (44.1-55 mm TL) were omnivore with higher tendency of feeding on debris, aquatic plants, green algae, blue-green algae and rotifera. However, the fish of the size group IV (55.1-80 mm TL) were found to be herbivore with feeding preference for aquatic plants, green and blue-green algae. In all the size groups, debris was the most dominant food item. Feeding preference of the fish showed clear ontogenetic shift. The electivity indices revealed that the fish were selective feeder

Optical and morphological characterization of BaSe thin films synthesized via chemical bath deposition

Barium selinide (BaSe) thin films were deposited onto glass substrate via chemical bath deposition (CBD) method. The effect of deposition time on the thin film formation mechanism has been studied to understand the optimum conditions for synthesis process. The phase identification and surface morphology of thin coated films were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively while the optical characterizations were conducted by means of ultraviolet visible (UV- Vis) spectroscopy. XRD study confirms the polycrystalline hexagonal structure of the thin films. The XRD peaks at 2θ =23.84° and 2θ = 23.86o showed the preferential orientation along the (021) and (201) plane with deposition time 20 hours and 22 hours respectively, whereas the major peak at (111) was obtained with a deposition time of 24 hours. With the increase in deposition time up to 24 hours, the film gradually grew thicker along with the fine increase in the grain size. The direct optical band gap of the films was measured to be varied from 1.33 to 3.37 eV

Studies on the growth and production of six major and exotic carps in Nasti baor, Jhenaidah, Bangladesh

An investigation on growth, production and fishery of three Indian major carps: rohu, Labeo rohita, catla, Catla catla and mrigal, Cirrhinus mrigala and three exotic carps: silver carp, Hypophthalmichthys molitrix, grass carp, Ctenopharyngodon idella, and common carp, Cyprinus carpio was carried out in Nasti baor during February to April months. In catch per unit effort (CPUE) study the highest catch/day/person (3.13 kg) and catch/day/gear (40.65 kg) was recorded in the month of March for kochal fishing. In komar fishing catch/day/person (15.08 kg) and catch/day/gear (1206 kg) was also found higher in March. Komar fishing was done only in March and April and its CPUE was greater in both the months than that of kochal. The average recovery rate (combination of all six species) was 37.80 considering the stocking from July month of the previous year. The recovery rate of common carp (54.1) was the highest and lowest (13.90) in case of silver carp. When the recovery was calculated on the basis of one year data and stocking, it was 55.6%. Analysis of production model revealed that the present production (54,806 kg/year) is less than both theoretical production (model I- 85,285 kg/year and model II -75,952 kg/year) estimated. Therefore, it may be concluded that the fish production from Nasti baor could still be increased from the present level of production

Study on fishing gears, species selectivity toward gears and catch composition of BSKB beel, Khulna, Bangladesh

An investigation on the types of fishing gear used and their species selectivity and effects on fishes of BSKB beel in Khulna was conducted from June '95 to January '96. Fishermen were found to follow 6 fishing techniques viz., netting, trapping, angling, spearing, dewatering and hand picking. Among them 23 types of the fishing gear was recorded to be used by the fishermen of which 7, 8, 4 and 4 are nets, traps, hooks and lines, and hand harpoon respectively. A total of 47 species of fish were identified in the catches of different gears used by the fishermen in BSKB beel. Particulars, mode of operation, fishing season and catch composition of different fishing gears were determined. Seine, cast and lift net, traps (charo, arinda and ghuni), and hooks and lines (dhawn and nol broshi) were recorded as nonselective gear considering the fish species caught. However, gill nets (punti, koi and fash jal), clasp nets (bhuti jal), some traps (khadom, tubo), hooks and lines (chip borshi, chasra) and all spears were used as more or less selective gear. With respect to species and its size fash jal, bhuti jal, trap (khadom, ramani), and koach, juti and jhupi among spears were regarded to be more or less large-species-gear. But punti jal, koi jal, trap (koi dughair, charo, tubo, arinda and ghuni), nol borshi and spear (ful-kuchi) were small-species-gear. Among all gears seine net, cast net, lift net, koi dughair and ramani were recorded deleterious for carps especially for stocked fingerlings. For relatively small sized wild fishes koi jal, punti jal and ghuni traps were identified as detrimental gear

Development of Mission Control Unit Prototype for Small Class Satellite Payloads

In this paper, Mission Control Unit (MCU) prototype for small class satellite payloads is developed with the goal of providing schools and institutions to low cost design that could be easily integrated and augmented for mission–specific needs. Basic design platform has been developed to demonstrate the proof of concept model of MCU for small satellites by using commercial off-the-shelf (COTS) components. Many commercial companies have emerged to cater this objective however most of them provide expensive on-the-shelf solution, therefore this paper proposed a low cost, compact platform design. This paper presents the design of payload-ready prototype unit of mission control subsystem that is built on Arduino based microcontroller with wireless transmission by using COTS components. This platform is intended mainly for educational purposes, specifically to expose high school and university students or researchers to satellite engineering concept. Other than that, it is developed to provide platform for spacecraft developers, researchers and others to test their scientific missions or perform their research with reduced costs. In addition, the end-product of this project can be used for public outreach mission involving local communities of amateur radio operators and school students. This project has produced a prototype that is compatible with 2U CubeSat platform standard, requires no external wiring with all subsystems, and can be customized to perform many mission themes over amateur radio band

Screening of wheat (Triticum aestivum L.) lines against salinity under field condition

An experiment was undertaken in order to screening wheat genotypes against salinity under field condition with 14 wheat genotypes including 6 check varieties. The genotypes were tested in saline soil where the salinity of the experimental field ranges from 1.5 to 10.3 dS/m during the cropping period. Analysis of variance revealed significant variation among the genotypes for all characters. Phenotypic and Genotypic co-efficient of variation was low for almost all the characters. Phenotypic co-efficient of variation ranged from 8.42 to 23.45 for plant height and yield respectively, while the highest genotypic coefficient of variation (18.90) was observed in yield and lowest (6.83) was found in seed per spike. All of the trait exhibited moderate to high heritability in broad sense (h2b) coupled with a wide range of genetic advance and genetic advance in percentage of mean. Heritability ranged from 37.64`to 91.14 for seed per spike and thousand seed weight respectively. Yield had significant positive correlation with spike length, spikelet per spike, seed per spike, thousand seed weight. On the other hand, yield was found to show a positive relationship with tiller per plant. Tiller per Plant, spikelet per spike, 1000 seed weight were responsible for reduction of yield per plant indirectly. Yield ranged from 1.14 ton/ha to 2.1 ton/ha. The present research work clearly demonstrated that based on field performance considering yield, the genotypes BARI Gom 25 and BARI Gom 26 is best and other some genotypes BAW 1182, BAW 1177 respectively showed their most effective performance on saline soil