Vibrio cholerae still represents a significant threat to human health worldwide despite the advances in hygiene, consumer knowledge, food treatment and food processing. In Malaysia, statistics in year 2009 have shown that among the food and water borne diseases, food poisoning has the highest incidence rate of 36.17 per 100,000 populations and with a mortality rate of 0.01 per 100,000 populations. In this study, 22 seafood samples comprising of fish, squid, crustacean and mollusks purchased from wet market and supermarket were analyzed. The Most Probable Number (MPN) and real time PCR was used to enumerate the Vibrio cholerae in seafood sample. The results showed that MPN-real time PCR of the samples from wet market had a maximum of >1100 MPN/g compare to 93 MPN/g enumerated from the MPN plate. The MPN-real time PCR in the samples from supermarket indicated 290 MPN/g as compared to 240 MPN/g enumerated from the MPN plate. The standard curves showed that there was a good linear correlation between the Ct values. The minimum level of detection of Vibrio cholerae standard DNA at targeted gene was 3 x 10-5 ng/μl.
The Malaysian fish production is about 1.5 million metric tonnes and 86.9% of this comes from the marine sector and 13.1% from the inland sector. This included fish production by capture and culture. (DOF, 2002). Fisheries genetic resources need to have a value in terms of economic, ecological and social uses and they need to characterized. This is the mandate to FAO and it is also necessary for fisheries management and aquaculture development. The vast aquatic diversity that exists in Malaysia consist of numerous taxa of marine and freshwater fishes, crustaceans, mollusks, plants and animals. These figures could be an underestimate to the actual figure. The levels of genetic diversity includes ecosystems, communities, population, genotypes and individual genes. A knowledge of the genetic background of a species and its population structure is essential for its management, breeding and conservation programmes in fisheries. Problems like how to choose the right candidates for breeding, identifiying and monitoring lines, families and individuals, monitoring and control of inbreeding, inheritance of simple traits and genetic improvement through selection for favourable gene and gene combinations can potentially be answered through the use of molecular markers in the management of fisheries genetic resources.
Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.
The relationship between a putative metallothionein gene (MT) and exposure to cadmium (Cd) in blood cockles (Anadara granosa) is reported. In a 96-h dose-response experiment, mortality of cockles was found to proportionately increase in the range of 0.2-5.0 mg/l Cd with a calculated LC(50) of 2.94 mg/l. Exposure to 0.25 mg/l Cd for 16 days caused significant increases (P<0.05) in Cd concentrations in whole tissues, gills and hepatopancreas, and the accumulation of Cd in these tissues increased with the duration of exposure. Two cDNA libraries constructed using the hepatopancreas from control and Cd-treated cockles gave titres of 5.62 x 10(5) and 1.94 x 10(5) pfu/microg vector, respectively. A putative MT gene, AnaMT, of 510 nucleotides in length, was isolated from the treated cDNA library using a heterologous probe MT20 from the blue mussel, Mytilus edulis. Northern analyses using AnaMT as a probe indicated low expression of the MT mRNA in control animals. In cockles treated with 0.25 mg/l Cd for 4 days, MT mRNA level increased to approximately 168%, but declined to 108% at day 8. After 12 and 16 days of Cd treatment, expression of the MT gene was 138% and 187%, respectively, compared to the controls. These observations suggest that induction of the MT gene by a sublethal dose of Cd is rapid, occurring within 4 days of treatment.
The occurrence, level, and distribution of multiclass emerging organic contaminants (EOCs) in fish and mollusks from the Klang River estuary were examined. The targeted EOCs for this assessment were phenolic endocrine disrupting compounds (bisphenol A, 4-OP, and 4-NP), organophosphorous pesticides (quinalphos, chlorpyrifos, and diazinon), estrogenic hormones (E2, E1, and EE2), and pharmaceutically active chemicals (primidone, sulfamethoxazole, dexamethasone, diclofenac, amoxicillin, progesterone, and testosterone). Results from this study showed that the prevalent contamination of the Klang River estuary by EOCs with diclofenac, bisphenol A, progesterone, and amoxicillin were predominantly detected in fish and mollusks. Among the EOCs, diclofenac and progesterone had the highest concentrations in fish and mollusk samples, respectively. The concentrations of diclofenac and progesterone in fish and mollusk samples range from 1.42 ng/g to 10.76 ng/g and from 0.73 ng/g to 9.57 ng/g, respectively. Bisphenol A should also be highlighted because of its significant presence in both fish and mollusks. The concentration of bisphenol A in both matrices range from 0.92 ng/g to 5.79 ng/g. The calculated hazard quotient (HQ) for diclofenac, bisphenol A, and progesterone without consideration to their degradation byproduct were less than one, thus suggesting that the consumption of fish and mollusks from the Klang River estuary will unlikely pose any health risk to consumers on the basis of the current assessment. Nonetheless, this preliminary result is an important finding for pollution studies in Malaysian tropical coastal ecosystems, particularly for organic micropollutant EOCs, and can serve as a baseline database for future reference.
The presence of natural radioactivity and (137)Cs has been investigated in fresh media obtained from South China Sea locations off the coast of peninsular Malaysia. The media include seafood, sea water and sediment. The samples were collected some weeks prior to the devastating 2011 Tōhoku earthquake and associated tsunami, the occurrence of which precipitated the Fukushima incident. All samples showed the presence of naturally occurring (226)Ra, (228)Ra and primordial (40)K, all at typically prevailing levels. The concentrations of natural radioactivity in molluscs were found to be greater than that of other marine life studied herein, the total activity ranging from 337 to 393 Bq kg(-1) dry weight. The total activity in sea water ranged from 15 to 88 Bq l(-1). Sediment samples obtained at deep sea locations more than 20 km offshore further revealed the presence of (137)Cs. The activity of (137)Cs varied from ND to 0.5 Bq kg(-1) dry weight, the activity increasing with offshore distance and depth. The activity concentrations presented herein should be considered useful in assessing the impact of any future radiological contamination to the marine environment.
The principal etiologic agent of human eosinophilic meningitis, Angiostrongylus cantonensis, was first detected in rats in Canton, China in 1933. The first human case was detected on Taiwan in 1944. Epidemic outbreaks were noted on Ponape (E. Caroline Is.) from 1944 to 1948. The disease may present as transient meningitis or a more severe disease involving the brain, spinal cord and nerve roots, with a characteristic eosinophilia of the peripheral blood and CSF. Since 1961 it has been known that human infections are usually acquired by purposeful or accidental ingestion of infective larvae in terrestrial mollusks, planaria and fresh-water crustacea. There is no effective specific treatment. The African land snail, Achatina fulica played an important role in the panpacific dispersal of the organism: it will be important in Africa in the future as well. Rats were, and will continue to be the principal agents of expansion of the parasite beyond the Indopacific area. During and just after WWII the parasite was introduced, and/or spread passively from South and Southeast Asia into the Western Pacific islands and eastward and southward through Micronesia, Melanesia, Australia and into Polynesia, sequestered in shipments of war material and facilitated by post-war commerce. In the 1950s numerous cases were identified for the first time on Sumatra, the Philippines, Taiwan, Saipan, New Caledonia, and as far east as Rarotonga and Tahiti. Then cases were detected in Vietnam, Thailand, Cambodia, Java, Sarawak, the New Hebrides, Guam and Hawaii during the 1960s. Subsequently in the Pacific Basin the disease has appeared on Okinawa, other Ryukyu islands, Honshu, Kyushu, New Britain, American Samoa and Western Samoa, Australia, Hong Kong, Bombay, India, Fiji and most recently in mainland China. The parasite in rats now occurs throughout the Indopacific Basin and littoral. Beyond the Indopacific region, the worm has been found in rodents in Madagascar (ca 1963), Cuba (1973), Egypt (1977), Puerto Rico (1984), New Orleans, Louisiana (1985) and Port Harcourt, Nigeria (1989). Human infections have now been detected in Cuba (1973), Réunion Island (1974) and Côte d'Ivoire (1979) and should be anticipated wherever infected rats of mollusks have been introduced. Caged primates became infected in zoos in Hong Kong (1978) and New Orleans and Nassau, Bahamas (1987). The use of mollusks and crustacea as famine foods, favored delicacies and medicines has resulted in numerous outbreaks and isolated infections. Economic and political instability, illicit trade, unsanitary peridomestic conditions and lack of health education promote the local occurrence and insidious global expansion of parasitic eosinophilic meningitis.(ABSTRACT TRUNCATED AT 400 WORDS)