300 research outputs found
Feeding ecology and food preferences of carcinoscorpius rotundicauda collected from the Pahang nesting grounds
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
Accumulation and distribution of lead and copper in avicennia marina and rhizophora apiculatafrom Balok Mangrove Forest, Pahang, Malaysia
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
Universal reliance on LAL/TAL in bacterial endotoxin detection in drugs and parenteral โ an ecological and economic perspective
Introduction: Endotoxin detection and quantification in biological drugs and parenteral is
a crucial step in helping us to be confident in process control (IPC) and product release
decisions. Food and Drug Administration (FDA) approves either Limulus Amebocyte Lysate
(LAL) /Tachypleus Amebocyte Lysate (TAL) derived from blue blood of horseshoe crabs to
detect and quantify endotoxin. This in turn increases harvest pressure on wild crabs for
biomedical bleeding practice which eventually leads to post bleeding mortality up to 30%.
In economic perspective, the LAL/TAL industry worth more than 50 million USD annually.
Methods: Numbers of methods were adopted to enhance the accuracy of endotoxin
detection, including gel clot, turbidimetric and chromogenic method. Results: However,
all these methods require crabs either from wild or from captive for bleeding purpose.
Though, various conservative measures are being taken, the habitat degradation and
anthropogenic pressures on wild crab population is still beyond control and leads to
unsustainable utilization of natural stock. Conclusions: Due to an increased demand of
LAL/TAL, the present review paper addresses the issues related to Eco-economical
viewpoint on sustainable utilization of wild stock for future LAL/TAL industry. It also
addresses pros and cons of recent advanced sensor technology in rapid and low cost
detection of endotoxin
Bioaccumulation of some essential metal concentration in Malaysian horseshoe crabs (tachypleus gigas)
We examined the selected essential metals (Fe and Zn) accumulative concentrations in different
body parts of Malaysian horseshoe crabs [Tachypleus gigas (Muller, 1785)]. Metal accumulation
levels were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS).
Average concentration (ฮผg g-1
wet weight) of iron (Fe) and Zinc (Zn) were observed in gill tissue
(1336.73ยฑ2.08 ppm) and apodeme (921.11ยฑ8.12 ppm) respectively. The lowest concentrations of
metals were observed in gut (Fe = 556.61 ppm) and mouth (Zn = 605.36 ppm) tissue portions.
Results clearly showed that bioaccumulation of both the essential metals were higher in the body
parts but lower than the maximum permissible limit set by the national and international
consortia. Statistical predictions revealed that bioaccumulation of metals were not significantly
influenced by weight, total length and carapace width of the animal
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