Endotoxins (chemically known as Lipopolysaccharide) from gram-negative microorganisms initiates clot formation in blood when it is accidentally encountered by horseshoe crab blood stream. This property was extensively studied by various researchers as a result Limulus Amebocyte Lysate (LAL) test was established. The LAL tests in general, 3 to 300 times more sensitive than the United States Pharmacopeial (USP) rabbit pyrogen test method. It is apparent that major differences among the LAL preparations lie in the area of sensitivity. Differences, up to 100-fold, exist in the sensitivity of the various LAL preparations to the same endotoxin. Based on the above perspective, a portable Kit (Endo sensor) was developed to detect the presence of bacterial endotoxin in liquid biological samples using Tachypleus Amebocyte Lysate (TAL) as a source. Sensitivity of the Kit was determined using various concentrations of prepared endotoxin standards and pyrogen free water samples. It was observed that Endo sensor could detect up to nano gram level of endotoxin in liquid biological samples which could be expressed in (EU/ml) and the labeled sensitivity of the lysated product was 0.125 EU/ml. The gel clotting principle method was utilized for the detection of bacterial endotoxin in liquid biological samples.
The first time report on the feeding ecology and food preference of mangrove horseshoe crab Carcinoscorpius rotundicauda (Latreille 1802) at their nesting grounds along the Pahang coast is given. Monthly sampling was carried out between March 2010 and February 2011 covering both monsoonal (March to October) and non-monsoonal (November to February) seasons. Major macrobenthic gut contents (bivalves, gastropods, crustaceans, polychaetes and miscellaneous food items including plant materials) were identified using microscopic examination. An electivity index (E1) was calculated for the frequent food items observed in the gut region of C. rotundicauda during monsoon and non-monsoon seasons. The EI was negative for crustaceans and positive for all the other food items including bivalves, gastropods, polychaetes and miscellaneous food items (which include insects, amphipods, Isopods, larval and juvenile stages of fishes, foraminifera and other Annelid worms). It is interesting to note that C. rotundicauda prefered less number of bivalves than polychaetes during non monsoon seasons but it was the reverse during monsoonal period. Male crabs intensely preyed on gastropods and female prefers polychaete worms during the peak mating/nesting season (June - August 2010). Seasonal variations in food composition showed that mollusks formed the main item especially gastropods. Unidentified organic matters in the gut content analysis of C. rotundicauda showed high preference towards plant materials. Gastro Somatic Index (GaSI) analysis showed that the feeding intensity of male crabs was higher during non-monsoon period while it was higher during monsoonal period in female crabs. In conclusion, the feeding ecology of mangrove horseshoe crabs were more similar to its closer and distant conspecifics. However, it was postulated that the higher preference of polychaete worms by the female C. rotundicauda during the peak mating season indicated its role in regulating the nesting behaviour.
Increasing utilization of living animals in ecological and biomedical research has drawn serious concerns in terms of animal welfare and ethical practices in animal handling. Significant attention has been given to animals of higher taxonomical hierarchy especially vertebrates such as fishes, rodents, reptiles and mammals, while ethical framework on invertebrate handling and welfare is less addressed (except for cephalopods). The definition of ‘Animal’ itself by any international consortia or Animal Research Act (ARA) does not include invertebrates as an animal entity. This is due to the lack of standard ethical framework to understand the pain and other physiological stress experienced by the invertebrate test animal. One such example would be the living fossil ‘horseshoe crab’ which is extensively bled to obtain its blue blood that is used for endotoxin quantification in biological samples. The biomedical bleeding itself leads to 15-30% post bleeding mortality of crabs, while pain and stress caused by the bleeding practice is not studied. Hence, this paper discusses the technicality of establishing standard framework for invertebrate handling. The paper also highlights the shari’ah (Islamic law) principles on scientific experimentations on animal subjects, particularly the norms related to the adoption of invertebrates in environmental and biomedical practice. Comprehensive review of ethical regulations in animal experiments, especially invertebrates, would be beneficial for revising and improving existing animal ethical practices.
Microorganisms are the major cause of spoilage of most seafood products. Fishes are more perishable than other protein foods and thus more prone to bacterial contamination. Based on above perspectives, a bacterial invasion in commercially important fresh and spoiled marine (Lates calcarifer, Lutjanus sanguineus) and freshwater fish (Pangasius pangasius) were analyzed using API 20E kit. Out of 25 isolates obtained from fresh water fish, only 6 isolates were characterized as Gram-positive bacteria and the rest were Gram negative strains (19 isolates). The most dominant genera were Vibrio, Enterobacter, Serratia, and Aeromonas. All these bacteria were found in both fresh fish and spoiled fish sample while Erwinia spp. and Kluyvera spp. were identified only in fresh fish samples. Out of four (4) strains of Staphylococcus spp., S. xylosus was detected exclusively from spoiled fish. The higher number of bacterial micro flora in the spoiled fish gut indirectly indicated increased microbial degradation in the fish gut during spoilage process. Notably, almost all the isolates were lactose degraders, positive oxidizers and carbohydrate fermenters. Vibrio fluvialis, Proteus mirabilis, Proteus vulgaris, Brucella sp. and Ochrabactrum anthropi were the human pathogenic bacteria found in marine fish Lates calcarifer (Sea perch). While Vibrio fluvialis, Proteus mirabilis and Proteus vulgaris were detected in Lutjanus sanguineus (Red snapper). The study portrays that the existing postharvest handling techniques could be a vital factor for degrading hygienic conditions of fish in local fish markets. Nevertheless, a long term monitoring is an urgently needed for sustaining the quality flesh of fish towards the betterment of the consumer’s health.
Mysis, post larvae and adult specimens of Penaeus monodon were sequenced for Cyctochrome C Oxidase subunit I (COI) gene (DNA barcode) to check the efficiency of DNA barcode in delineating species irrespective of its different life stages. COI gene sequences of different life stages of P. monodon were subjected to pair-wise distance analysis, nucleotide sequence diversity estimation, phylogenetic and BOLD analysis. The pair-wise distance estimation revealed that intra-specific variations within the barcode sequences of P. monodon were low when compared with other species of genus Penaeus spp. The average pair-wise distance within the sequences of different stages of P. monodon was two times lesser than the pair-wise distance of the out-group used. The nucleotide diversity within the barcodes were low (π = 0.324). The constructed phylogram clearly showed that the DNA barcoding using partial COI gene would provide an accurate delineation of species irrespective of their different life stages. The BOLD analysis accurately identified all sequences as belonging to P. monodon.
Bioaccumulation of lead and Copper in Avicennia marina and Rhizophora apiculata was studied. Samples of leaves, barks and roots were collected from Balok mangrove forest, Pahang. Pb and Cu accumulation was higher in Avicennia marina root tissue compared to bark and leaf but lower than surrounding sediment level. The average concentration of Pb in A. marina leaf, bark, root and sediment was observed to be 5.39 ppm, 3.63 ppm, 18.21 ppm and 23.13 ppm, and average Cu concentration was 4.13 ppm, 4.27 ppm, 4.81 ppm and 12.33 ppm, respectively. R. apiculata also showed higher concentration of Pb and Cu in root tissue compared to bark and leaf tissues but lower than surrounding sediment. The average concentration of Pb in R. apiculata leaf, bark, root and sediment was observed to be 4.30 ppm, 2.97 ppm, 22.45 ppm and 31.23 ppm, respectively. The average Cu concentration was 2.93 ppm, 4.71 ppm, 4.81 ppm and 15.52 ppm, respectively. Results of concentration factors (CF) showed that the accumulation of Pb and Cu was higher in A. marina than in R. apiculata.
In recent decade, aquaculture species, including fish are under danger from bio-aggressors like viruses, bacteria, parasites and fungi. These organisms harm either spontaneously or through aquatic animal husbandry practices or both. The chemicals employed in aquaculture are drugs like antibiotics used to treat diseases, chemicals introduced through construction materials and hormones used to alter the reproductive viability, sex and growth rates. Drugs used to treat disease are the most dangerous to the fish. These persistent antibiotics tend to increase antibiotic-resistant free-living bacteria, thereby altering the composition of normal marine and freshwater bacterial flora. Evidence suggests that these antibiotic-resistant organisms in the marine environment will, in turn, pass their antibiotic resistance genes to other bacteria including human and animal pathogens. Antibiotic treatment in aquaculture is achieved by medicated baths and medicated food. In both cases, the probability exists for antibiotics to pass into the environment, affecting wildlife, remaining in the environment for extended periods of time and exerting their antibiotic effects to human. In this manner, potential alterations of the diversity of the marine micro-biota produced by antibiotics may alter the homeostasis of the marine environment and affect complex forms of life including fish, shellfish, marine mammals, and human beings. The contamination of surface waters with antimicrobials has become an increasing public health concern because of the emergence of multi-resistant pathogens. Efforts to make progress on these issues require us to raise, confront and enact some difficult ethical decisions that will affect the living standard of human. Nevertheless, excessive antibiotic use in aquaculture should be of high concern to the aquaculture industry and its regulators, to public officials dealing with human and animal health and with the preservation of the environment, and to non-governmental organizations dealing with these issues.
The data available in this repository were gathered from Balok, the only most productive spawning site for horseshoe crabs Tachypleus gigas and Carcinoscorpius rotundicauda in East Coast of Peninsular Malaysia. The mangrove horseshoe crab, C. rotundicauda population and spawning data are available in the first table. The horseshoe crabs were retrieved from Balok River using 11.43 cm mesh size gill nets installed at the river mouth, the confluence and last meander. The arthropods were inspected for damage, abnormality and growth before their release into Balok River, particularly at the site of capture. Sediment samples were retrieved at their spawning grounds to ascertain sediment composition and size classifications which were also processed using Logarithmic Method of Moments. Water parameters like temperature, pH and salinity were also investigated during year 2016. All these information are compiled into the second table and arranged according to the period of data availability. The horseshoe crab catch data of years 2012, 2013, 2014, 2015 and 2016 were made available by artisanal fisher and compiled in the third and fourth table for inter-species comparison.
Carcinoscorpius rotundicauda and Tachypleus gigas may co-exist and share common spawning grounds elsewhere but at Balok (East Coast of Peninsular Malaysia), C. rotundicauda is an understudied species. Neglected as research candidate because of inaccessible spawning grounds, smaller size and less commercial value than T. gigas and also, difficulty to attain from the wild has made C. rotundicauda population status remaining unidentified at Balok. This standpoint drove the present attempt because anthropic activities like structure placement and mining are point-source for runoffs that load sediments into Balok River. While erosion-accretion events have altered Balok River width, the shore sediments in Balok Beach were transitioned between medium-fine and fine sand between years 2012 and 2016. Eventually by year 2016, the C. rotundicauda were depositing 5117 eggs in 91 nests from 200 to 1000 m range along this corridor facing South China Sea. From this yield, C. rotundicauda released 2880 eggs in 56 nests during the Southwest monsoon, 1254 eggs in 19 nests during the Northeast monsoon and 983 eggs in 16 nests during the Inter-monsoon seasons. Though female C. rotundicauda opted to lay their eggs in shallow burrows at lower shorelines, the absence of erosion and substantial silt and clay (>20%) deposition facilitates C. rotundicauda embryogenesis with brief periods of temperature and salinity shocks during day-time falling tides. This encourages C. rotundicauda to emerge with increasing abundance and carry out bi-monthly spawning at Balok Beach. In short, shore restoration initiatives like systematic boat docking, proper disposal of nets and waste and, periodic fish-catching operations were effectively led by the Balok fisher citizen scientist. This successful community joint-cooperation proves that citizen-led caretaking of degraded beaches offers marine life protection and are practical for coastal area management especially at areas where other oviparous animals such as turtles and crocodiles are harboured.