The present study was concerned to assess the present status of biodiversity in the Bhairab river, Jessore with its conservation measures. The study was based on primary observations, questionnaire interviews with 50 fishers, focus group discussions with river bank community members and cross-check interviews with key informants. The study was conducted for a period four months from May to August, 2016. The objective of the study was to assess the fish biodiversity in the Bhairab river, understand the existing fishing practices of the river and to identify proper management strategies for the conservation of fish biodiversity. Results of the study revealed that three kinds of fishers were engaged in the Bhairab river namely, professional fishers; seasonal fishers and subsistence fishers. Seven types of fishing gears like seine net, gill net, cast net, push net, lift net, trap and hook and line were operated to fish by the fishers during the survey. A total of 39 species of fish were identified in the catches of the Bhairab River. There are degraded ecosystems and declining biodiversity have found during the study. According to survey, fishing pressure and over fishing were responsible for almost 38% loss and pollution and siltation caused about 27% loss of ecosystem. Around 21% and 14% loss of ecosystem were caused by urbanization and human encroachment, and the recreational activities respectively. These have been created a great impact on river ecology. As a result, the water quality is deteriorating day by day and the availability of fish species and other aquatic biodiversity is decreasing gradually. During the survey, 20 species was found at a risk of being endangered. From the survey, it was found that the overexploitation of fish was responsible for the 40% losses of biodiversity in the Bhairab River and water pollution caused 35% loss of biodiversity. Henceforth, river course change and habitat degradation resulted in 15% and 10% loss of biodiversity of the river respectively. This study was identified possible ways to achieve a rich fish biodiversity in the Bhairab River with social, economic and environmental aspects. The specific recommendations are included community based fisheries management, establishment of sanctuary, control of pollution, maintenance of fishing gears and the implementation of fish act for conservation of fish biodiversity of the Bhairab River.Asian J. Med. Biol. Res. September 2017, 3(3): 357-367

Al-Asif A, Hamli H, Abu Hena MK, Idris MH, Gerusu GJ, Ismail JB, Karim NU. 2020. Benthic macrofaunal assemblage in seagrass-mangrove complex and adjacent ecosystems of Punang-Sari Estuary, Lawas, Sarawak, Malaysia. Biodiversitas 21: 4606-4615. Present study dealt with the on faunal and in faunal assemblage from seagrass bed, mangrove area, and adjacent non-mangrove and seagrass (NMS) in Punang-Sari estuary, Lawas, Sarawak, Malaysia. Samples were collected from June to July 2019 by using quadrates and handpicking from the outside the sampling area to know the real checklist of surface macrofauna in this area. A ten-meter transect line was settled in three habitat areas where sampling was performed by putting three quadrates (0.35m×0.35m). Epifauna and infauna samples were collected from inside the quadrate and sieved using 0.4 mm mesh size sieve. A total of 111 species of gastropod (87 species from 30 families), bivalve (18 species from 9 families), Polychaeta (2 species), echinoderms (1 species), and crustacean (3 species) were recorded during the study period. Seagrass meadows comprised most diverse and abundant faunal (50 species) assemblage followed by mangrove habitats (48 species), and NMS (20 species). The dendrogram revealed two significant habitats in the sampling site. PCA analysis revealed, seagrass habitat sheltered a higher number of species followed by mangrove and NMS area. Jaccard similarity index revealed seagrass and mangrove habitats (0.42) contains the highest similar species amongst all habitats compared to mangrove and non-seagrass-mangrove area (0.26). Out of total species recorded (101), only ten species were reported as least concern, and 2 species hold deficient data status, and the rest are not evaluated. Bio-assemblage in seagrass habitat was found rich compared to other habitats, which could be useful for future ecological investigation and marine ranching.

Common carp (Cyprinus carpio) is one of the commercially important and commonly cultured fish. In the hatchery intensive incubation leads to microbial overgrowth in C. carpio eggs that hamper egg development, hatchability and larval survivability. The aim of this study is to find out causes of mass mortality in C. carpio eggs during peak- breeding season between March to May 2015 at Mafatema fish hatchery, Chanchra, Jessore sadar upazilla. In the present study three disinfectants with three different concentrations in each such as methylene blue 1, 3 and 5mg/L., malachite green 1, 3 and 5mg/L., sodium chloride 1, 2 and 3g/L were used to observe the hatching rate of fertilized eggs and survival rate of larvae. Bacterial load of culture water was examined during the induced breeding of C. carpio with mycological examination of egg samples with different disinfectants. The total bacterial count fluctuated from 3.4 x 108 CFU/ml to 32.7 x 108 CFU/ml during the period of fertilization to 4days of hatching. The fertilized eggs infected by Saprolegnia spp. were appeared as tuft hairy like balls with a white cottony envelop. Among all the treatment 1mg/L methylene blue, 3mg/L malachite green and 1g/L sodium chloride showed significantly better (P<0.05) hatching rate 95·33±2·08, 88.00±2.64 and 92.33±4.04% respectively. The same concentration of methylene blue, malachite green and sodium chloride showed significantly better (P<0.05) better survival rate 95·00±4.35, 75.00±3.00 and 87.00±6.24% respectively. Finally among all the treatment 1mg/L of methylene blue showed significantly better (P<0.05) hatching and survival rate 95·33±2·08% and 95·00±4.35 % respectively. So 1mg/L of methylene blue is the best disinfectant for C. carpio fertilized egg treatment.Asian J. Med. Biol. Res. December 2015, 1(3): 578-588

Aquaculture medicines, drugs, and chemicals or simply AMDC, are critical in protecting aquaculture farmers from disease in farmed animals and economic losses. The AMDC is now a well-established industry in Bangladesh, and each year, new products that benefit farmers are launched. This review examined published research information on AMDC over the last decade (2011-2020) and discovered that 41 research publications from various parts of Bangladesh were published, citing the names of 1484 AMDC products. It was discovered that 19 generic antibiotics are well established and widely used in different regions' aquaculture, including shrimp aquaculture. Although some researchers expressed concern about the use of antibiotics in aquaculture, they believe that with proper withdrawal periods and the application of small doses, farmers may avoid economic losses. However, the pathway of the antibiotic introduction in aquaculture setup in Bangladesh was unknown to the researchers, through this review, we revealed the pathway of antibiotics introduction in aquaculture. Additionally, this review revealed that various AMDC products, including oxygen suppliers, growth promoter supplements, disinfectants, raw chemicals, probiotics, pond preparation and management AMDC, and toxic gas removal AMDC, are readily available in various markets throughout Bangladesh. The observation implied that research on the efficacy of various AMDC products in Bangladesh's agro-ecological zones could be conducted, which would aid researchers in deciphering the true nature of AMDC in sub-tropical climates. Asian J. Med. Biol. Res. 2021, 7 (2), 90-106

Seagrass habitats are considered to be some of the most biodiverse ecosystems on the planet and safeguard some ecologically and economically important fauna, amongst which are some globally threatened species, including dugong. Malaysian seagrass ecosystems are not widespread, but their existence supports some significant marine fauna. A rigorous zooplankton study was conducted from May 2016 to February 2017, in the seagrass habitat of Lawas, Sarawak, Malaysia, to examine their temporal composition and diversity, together with their ecological influences. A total of 45 zooplankton species from 13 significant groups were recorded in the seagrass habitat. The population density of zooplankton ranged between 2,482 ind/m³ and 22,670 ind/m³ over three different seasons. A single zooplankton copepod was found to be dominant (47.40%), while bivalves were the second largest (31.8%) group in terms of total abundance. It was also noticed that the average relative abundance (0.62) and important species index (62.08) of copepods were higher than for other groups that exist in the seagrass meadow, whereas copepod Parvocalanus crassirostris showed both the highest average relative abundance (0.41) and the highest important species index (41.15). The diversity (H') and richness index of the intermediate season were found to be highest due to favourable physico-chemical conditions. Within the referred seasonal cluster, the wet and dry seasons were almost similar in terms of species abundance, while the intermediate season was distinct, with high species diversity backed by ANOSIM analysis results. Copepod and bivalves formed one group with a common similarity level of 0.80. The CCA (Canonical Correspondence Analysis) model established that abiotic factors, especially turbidity, NO₂, rainfall, dissolved oxygen and pH were significantly correlated with abundance of individual groups of zooplankton. Zooplankton assemblage and abundance in Lawas were found to be very rich in multiple seasons, indicating that the productivity of uninterrupted seagrass habitat might be high and the system rich in biodiversity.