Objective: The study was carried out to investigate the use and impact of veterinary drugs, antimicrobials, and supplements in commercial aquaculture for fish health management measures in three selected areas of Mymensingh, Bangladesh. Materials and Methods: Data collection was conducted through questionnaire interviews with owners of 50 fish farms and 25 drug shop owners from Trishal, Fulpur, Tarakanda, and Sadar Upazila of Mymensingh district. Results: A total of 15 trade-named veterinary antibiotics and six categories of other compounds were identified in this study. Antibiotics were found as the most used veterinary drugs (80.85%), followed by disinfectants, nutritional supplements, saline, ammonia removal agents, probiotics, and pesticides. These veterinary compounds’ performances for fish health management were found to vary (10%–60%) significantly. Conclusion: This study’s findings urge the necessity to produce and approve effective aqua drugs and treatments to ensure farmed fish and public health.

Quality and healthy fish seed is the prerequisite for sustainable aquaculture. A major challenge to the expansion of aquaculture production is the outbreak of diseases. Disease induced mortality is a serious issue for the fish seed industry. The immature immune system in fish makes the early developmental stages more susceptible to infectious diseases. Common fish diseases in hatcheries and in early rearing systems are caused by protozoan, ciliates, myxosporodians, worms, opportunistic bacteria and fungi. Production of healthy fish seed and their survival rate depends on the proper health management strategies, maintenance of good water quality, proper nutrition and application of biosecurity measures. The paper highlighted the different types of diseases, causative agents and their prevention and control measures in fish hatcheries and nurseries.

Growth performance of guppy fries was assessed by providing four different types of formulated diets comprised of some available ingredients (fish meal (FM), prawn meal (PM), meat and bone meal (MBM), wheat flour (WF), corn flour (CF), starch (S) and soya bean oil) and the result was compared with supplied commercial diet as control. After 30 days experimental period, diet 1 (FM: PM=6:1) showed the best result in case of length gain (0.48 cm) in guppies whereas lowest (0.01 cm) was reported from diet 2 (PM: MBM= 4:3). The body weight gain in guppies was also found higher (0.004 g) in diet 1 than other diets. Specific growth rate (SGR) of all formulated diets was between 1.03% to 4.8% while 0.7% was found in commercial diet. Maximum survival rate (95%) was recorded in formulated diet 1 whereas 80% was investigated in control .Growth trend of guppies from all the supplied formulated diets resulted better rather than the imported commercial diets. So, Commercial diets might be replaced by experimental diets for the better production of guppy.

Introduction. The research was carried out to investigate the concentration of heavy metals in fish and water samples collected from different locations of Chittagong District, Bangladesh. Materials and methods. The concentrations of heavy metals including Cr, Cu, Ni, Pb and Fe in sea water and marine fishes (pama croaker, bombay duck and rat-tail anchovy) were detected by using Air / Acetylene Flame Atomic Absorption Spectrophotometer along Chittagong City areas, Bangladesh. Results and discussion. The mean concentration of heavy metals were found in water in the range as Cr 0.0138-0.0789 mg/L, Cu 0.0014-0.0284 mg/L, Ni 0.0259-0.2519 mg/L, Pb 0.0109-0.1596 mg/L and Fe 0.2176-1.787 mg/L. The analysis of water samples showed that the distribution of heavy metals in the order of magnitude as Fe > Ni > Pb > Cr > Cu. The variation might be due to location, level of contamination in water through industrial effluents and anthropogenic activities. While the mean concentration of heavy metals were found in all fish samples in the range as Cr 3.2039-16.3495 mg/Kg dry wt., Cu 1.5589-4.5848 mg/Kg dry wt., Ni 0.1101-1.9029 mg/Kg dry wt., Pb 0.4373-2.7638 mg/Kg dry wt. and Fe 30.9599-108.780 mg/Kg dry wt. The distribution of heavy metals in fish samples analyzed were in the order of magnitude as Fe > Cr> Cu> Pb> Ni. The analysis showed that magnitudes of heavy metal were more or less similar with other researchers. The variation might be due to metal accumulation in fish and various fish species living in the same water body but different level of contamination in water. Among all samples, 17% fish samples had excess amount of Cr whereas acceptable limit is 15.0 mg/kg for fish. Mean concentrations of Pb in all fish samples were 17% below detection level, 33% optimum and 33% higher than the maximum permitted concentrations (1.5 mg/Kg). Fe in all fish samples were 33% below, 17% optimum and 50% higher than the maximum permitted concentrations (43 mg/Kg) recommended by FAO/WHO. Conclusions. Most of the fish species studied are safe to be consumed. Therefore, this study is proposed to draw the attention of health and environmental authorities in need for appropriate regulatory framework.

Sediment organic matter regulates the coastal biogeochemical cycle which is influenced by rainfall pattern and has potential relationship with organic carbon as well as mud characteristics. The objective of present research was to identify the impact of precipitation on the spatiotemporal variation inorganic features of intertidal mudflats. Three locations were selected in freshwater zone; two were in brackish water region and last three locations situated in marine waters from Halda to Salimpur coast. Two sites from each location were designated as the highest high tide level (onshore) and lowest low tide level (offshore) of the intertidal zone during winter (December to February) and monsoon (June to August) spanning between 2013 and 2014. Sediment organic matter and carbon were measured by combustion and Walkey-Black wet oxidation in turn. Average organic matter content in monsoon were found 4.5±0.03, 2.3±0.01 and 2.4 in freshwater, brackish and marine locations whereas 5.2±0.6, 3.9±0.14 and 5.4±0.04% investigated during winter. Precipitation pattern varies from different seasons and locations that have impact on land runoff, freshwater inflow, mixing and circulation. Mud dominated coastal intertidal zones represented high organic matter content than sand dominated coast. Furthermore, depositional pattern, transport, erosion-accretion processes, tidal action, wave characteristics and seasonal inconstancy control the organic matter characteristics in the coastal sediment. This research suggests the necessity of periodic observation of rainfall pattern and organic matter distribution to assess the intertidal deposits which support the stabilization of local geomorphology and biogeochemistry in Chittagong coastal region.Res. Agric., Livest. Fish.3(1): 175-186, April 2016