Shellfish aquaculture is an important component of global aquaculture, particularly because of the high economic value of many crustacean species. Among these crustaceans, mud crabs (Scylla spp.) are important high-value aquaculture species in tropical and subtropical Asia. Global farmed mud crab production increased from 150,751 tonnes in 2010 to 296,848 tonnes in 2021, with China contributing approximately 51% of global production, followed by Vietnam and the Philippines. Four species, S. serrata, S. paramamosain, S. olivacea and S. tranquebarica, are commercially important, although their distribution and importance in aquaculture vary among Asian countries. Mud crabs are mainly produced through pond, pen and cage grow-out, short-cycle fattening and soft-shell farming, while mangrove-integrated and other integrated farming systems are also practised. Despite the growth of the industry, production in several Asian countries remains dependent on wild-collected juveniles and fresh feeds. Disease occurrence, environmental impacts and market-related constraints further affect production and long-term sustainability. Recent advances in hatchery production, formulated feeds, health management and integrated farming offer opportunities to improve production efficiency and sustainability. Future development should prioritise reliable hatchery seed production, reduced dependence on wild resources, improved feed and farm management, effective biosecurity and protection of mangrove and other coastal habitats. Therefore, this review provides an updated synthesis of the current status and geographical distribution of mud crab farming in Asia, with particular emphasis on cultured species, culture and fattening systems, technological advances, environmental and socio-economic aspects, major production constraints and future priorities for sustainable industry development.
Israt Jahan Tumpa, T. K. Saha, Md. Hashibur Rahman et al.· Animal Reports· 0 citations
Heavy metal contamination has become a significant public health concern, particularly in rapidly industrializing and developing countries such as Bangladesh. Chronic exposure to toxic metals can cause serious health effects like cancer, cardiovascular disease, and kidney and liver failure. This study aims to evaluate the pollution level and associated health risks of heavy metal contamination in both industrial and non-industrial zones of the Turag River area in Gazipur District, Bangladesh. A total of 36 samples of soil and water were collected from 18 locations, covering both industrial and non-industrial zones from the Turag River. Five heavy metal concentrations, including arsenic (As), lead (Pb), cadmium (Cd), chromium (Cr), and copper (Cu), were measured using inductively coupled plasma-mass spectrometry (ICP-MS). Spatial mapping, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA) were conducted to identify the hotspot region, find possible sources, and categorize the metals or sites having a similar pattern. Pollution levels were evaluated using indices including the geo-accumulation index (Igeo), contamination factor (CF), pollution load index (PLI), heavy metal pollution index (HPI), and ecological risk factor (Er). Additionally, health risks were measured using the hazard index (HI) and the total cancer risk over lifetime (LCR). Our study reported that heavy metal concentrations in soil and water followed the order Cr > Cu > Pb > As > Cd in both zones, while industrial water samples showed Cu > Cr > Pb > As > Cd. In the industrial zone, the mean ± SD concentration of Cr in soil was found to be 52.22 ± 41.89 mg/kg, and Cu in water was found to be 1.70 × 10^(-2) ± 1.0 × 10^(-2) mg/L. The Igeo index indicated that Cd and Cu ranged from uncontaminated to moderately contaminated in both zones. Similarly, the CF and PLI indices showed low to moderate pollution levels from all types of metals, while Cu in industrial water showed a high level of pollution with a CF value of 8.52. Er values show that Cd and Cr pose a moderate ecological risk in both zones. All the pollution indices for most of the metals showed higher values in the industrial zone compared to the non-industrial zone. Moreover, carcinogenic risks were found for children in both zones, especially for Cr and As in soil. The results highlighted that heavy metal contamination and related health risks were more severe in the industrial zone, posing a significant threat to public health, particularly among children. Strict regulations and law enforcement on industrial emissions are essential to mitigate the risks.
Juned Hussain Chowdhury, Naimur Rahman Sarker, Md Jamil Hossain et al.· Discover Public Health· 0 citations
