Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beak... more Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beaked sea snake (Hydrophis schistosus, formerly known as Enhydrina schistosa) and the spine-bellied sea snake (Hydrophis curtus, formerly known as Lapemis curtus or Lapemis hardwickii) are two commonly encountered species. Australian CSL sea snake antivenom is the definitive treatment for sea snake envenomation; it is unfortunately extremely costly locally and is not widely available or adequately stocked in local hospitals. This study investigated the cross-neutralizing potential of three regionally produced anti-cobra antivenoms against the venoms of Malaysian H. schistosus and H. curtus. All three antivenoms conferred paraspecific protection from sea snake venom lethality in mice, with potency increasing in the following order: Taiwan bivalent antivenom < Thai monocled cobra monovalent antivenom < Thai neuro polyvalent antivenom (NPAV). NPAV demonstrated cross-neutralizing potencies of 0.4 mg/vial for H. schistosus venom and 0.8 mg/vial for H. curtus, which translates to a dose of less than 20 vials of NPAV to neutralize an average amount of sea snake venom per bite (inferred from venom milking). The cross-neutralization activity was supported by ELISA cross-reactivity between NPAV
Although tropical anguillid eels account for two-thirds of all species in the genus Anguilla, the... more Although tropical anguillid eels account for two-thirds of all species in the genus Anguilla, the information on the species diversity, geographic distribution, and life histories of the tropical eels is very limited. Recent studies suggested that accurate species identification in the tropical anguillid eels needs a validation by molecular genetic analysis after morphological observation. Two anguillid eels found in Sabah, Borneo Island, were firstly identified as Anguilla marmorata Quoy et Gaimard, 1824 using morphological analysis and further analysis of mitochondrial 16S ribosomal RNA (16S rRNA) sequences confirmed the morphological species identification. The presently reported study represents the first description of A. marmorata in Sabah, Borneo Island. One-year survey suggests that representatives of A. marmorata found in the region might belong to the North Pacific population in the westernmost distribution.
Recent studies suggested that accurate species identification in the tropical anguillid eels base... more Recent studies suggested that accurate species identification in the tropical anguillid eels based on morphological examination requires confirmation by molecular genetic analysis. Previous studies found that two tropical anguillid eels, Anguilla bicolor bicolor and A. bengalensis bengalensis, were found in peninsular Malaysia (West Malaysia) based on morphological and molecular genetic analyses. This study is the first record of A. marmorata in peninsular Malaysia confirmed by both morphological and molecular genetic analyses. The present study also suggests that accurate tropical eel species identification is difficult by morphological identification alone; therefore, molecular genetic analysis is needed for precise species confirmation.
Recent studies suggested that accurate species identification in the tropical anguillid eels base... more Recent studies suggested that accurate species identification in the tropical anguillid eels based on morphological examination requires confirmation by molecular genetic analysis. Previous studies found that two tropical anguillid eels, Anguilla bicolor bicolor and A. bengalensis bengalensis, were found in peninsular Malaysia (West Malaysia) based on morphological and molecular genetic analyses. This study is the first record of A. marmorata in peninsular Malaysia confirmed by both morphological and molecular genetic analyses. The present study also suggests that accurate tropical eel species identification is difficult by morphological identification alone; therefore, molecular genetic analysis is needed for precise species confirmation.
Recent studies suggested that accurate species identification in the tropical anguillid eels base... more Recent studies suggested that accurate species identification in the tropical anguillid eels based on morphological examination requires confirmation by molecular genetic analysis. Previous studies found that two tropical anguillid eels, Anguilla bicolor bicolor and A. bengalensis bengalensis, were found in peninsular Malaysia (West Malaysia) based on morphological and molecular genetic analyses. This study is the first record of A. marmorata in peninsular Malaysia confirmed by both morphological and molecular genetic analyses. The present study also suggests that accurate tropical eel species identification is difficult by morphological identification alone; therefore, molecular genetic analysis is needed for precise species confirmation.
THREE Universiti Sains Malaysia (USM) students from the School of Chemical Engineering have been ... more THREE Universiti Sains Malaysia (USM) students from the School of Chemical Engineering have been honoured with the best innovation award in the recently concluded R e s e a r c h a n d I n n o v a t i o n Competition (NRIC) 2014 through their unique innovation of water treatment from natural resources. Leslie Ewe Fang Jun, Muhammad Zamani Zakaria and Vjayan Thrumakunasagran came up with an innovation known as the Natural Biodegradable and Non-toxic Coagulant or a form of water treatment using natural substances extracted from dragon fruit trees. Vjayan said that most water treatment processing industries normally use chemicals such as aluminum sulphate (alum) and polyaluminium chloride (PAC) to treat dirty and contaminated wastewater. He said that the massive scale and long-term usage of the chemicals will contribute to health problems, for example, it may cause Alzheimer or neuron diseases such as a pre-senile dementia. " Therefore, we have conducted a study and found that dra...
The mud crab (Scylla) is a commercially important crustacean, as there is a large demand in many ... more The mud crab (Scylla) is a commercially important crustacean, as there is a large demand in many Southeast Asian countries. Currently, one of the main bottlenecks to the expansion of Scylla aquaculture is the inconsistent and low production of hatchery juveniles. One major challenge to overcome at the hatchery level is disease issues caused by bacteria. The use of probiotics to outcompete pathogenic bacteria is being tested in the industry as a better disease prevention method in Scylla aquaculture compared to antibiotics, and is getting more recognition in aquaculture to reduce bacterial issues. The current review discusses mudcrab farming activities in Malaysia and the scope for using probiotics in Scylla aquaculture, as this is a potential way to increase survival rates in a long term sustainable way.
The mud crabs, belonging to the genus Scylla, are commercially important crustaceans. However, on... more The mud crabs, belonging to the genus Scylla, are commercially important crustaceans. However, one of the major obstacles to the growth of Scylla aquaculture is the low supply of hatchery produced seed due to bacterial disease issues. Currently, antibiotics are used extensively in mud crab larval rearing to improve survival. However, the long term use of antibiotics poses numerous risks. The use of probiotics in crab larval culture can provide a long term solution to this problem. A berried female Scylla parammamosain broodstock was reared in an incubation tank till the eggs hatched. For the present test, larvae were given no probiotics (control) compared to larvae with commercial Bacillus probiotic added into the culture water (10 3 and 10 4 cfu/ ml daily). During the experiment, survival, yellow and green Vibrio colony counts, water quality, larvae stage index, and the percentage metamorphosized into the Z5 stage were monitored. There was a significantly higher survival rate in th...
In Malaysia, the growing interest in farming of the mud crab is hampered by supply of hatchery re... more In Malaysia, the growing interest in farming of the mud crab is hampered by supply of hatchery reared juveniles.
Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beak... more Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beaked sea snake (Hydrophis schistosus, formerly known as Enhydrina schistosa) and the spine-bellied sea snake (Hydrophis curtus, formerly known as Lapemis curtus or Lapemis hardwickii) are two commonly encountered species. Australian CSL sea snake antivenom is the definitive treatment for sea snake envenomation; it is unfortunately extremely costly locally and is not widely available or adequately stocked in local hospitals. This study investigated the cross-neutralizing potential of three regionally produced anti-cobra antivenoms against the venoms of Malaysian H. schistosus and H. curtus. All three antivenoms conferred paraspecific protection from sea snake venom lethality in mice, with potency increasing in the following order: Taiwan bivalent antivenom < Thai monocled cobra monovalent antivenom < Thai neuro polyvalent antivenom (NPAV). NPAV demonstrated cross-neutralizing potencies of 0.4 mg/vial for H. schistosus venom and 0.8 mg/vial for H. curtus, which translates to a dose of less than 20 vials of NPAV to neutralize an average amount of sea snake venom per bite (inferred from venom milking). The cross-neutralization activity was supported by ELISA cross-reactivity between NPAV
Although tropical anguillid eels account for two-thirds of all species in the genus Anguilla, the... more Although tropical anguillid eels account for two-thirds of all species in the genus Anguilla, the information on the species diversity, geographic distribution, and life histories of the tropical eels is very limited. Recent studies suggested that accurate species identification in the tropical anguillid eels needs a validation by molecular genetic analysis after morphological observation. Two anguillid eels found in Sabah, Borneo Island, were firstly identified as Anguilla marmorata Quoy et Gaimard, 1824 using morphological analysis and further analysis of mitochondrial 16S ribosomal RNA (16S rRNA) sequences confirmed the morphological species identification. The presently reported study represents the first description of A. marmorata in Sabah, Borneo Island. One-year survey suggests that representatives of A. marmorata found in the region might belong to the North Pacific population in the westernmost distribution.
Recent studies suggested that accurate species identification in the tropical anguillid eels base... more Recent studies suggested that accurate species identification in the tropical anguillid eels based on morphological examination requires confirmation by molecular genetic analysis. Previous studies found that two tropical anguillid eels, Anguilla bicolor bicolor and A. bengalensis bengalensis, were found in peninsular Malaysia (West Malaysia) based on morphological and molecular genetic analyses. This study is the first record of A. marmorata in peninsular Malaysia confirmed by both morphological and molecular genetic analyses. The present study also suggests that accurate tropical eel species identification is difficult by morphological identification alone; therefore, molecular genetic analysis is needed for precise species confirmation.
Recent studies suggested that accurate species identification in the tropical anguillid eels base... more Recent studies suggested that accurate species identification in the tropical anguillid eels based on morphological examination requires confirmation by molecular genetic analysis. Previous studies found that two tropical anguillid eels, Anguilla bicolor bicolor and A. bengalensis bengalensis, were found in peninsular Malaysia (West Malaysia) based on morphological and molecular genetic analyses. This study is the first record of A. marmorata in peninsular Malaysia confirmed by both morphological and molecular genetic analyses. The present study also suggests that accurate tropical eel species identification is difficult by morphological identification alone; therefore, molecular genetic analysis is needed for precise species confirmation.
Recent studies suggested that accurate species identification in the tropical anguillid eels base... more Recent studies suggested that accurate species identification in the tropical anguillid eels based on morphological examination requires confirmation by molecular genetic analysis. Previous studies found that two tropical anguillid eels, Anguilla bicolor bicolor and A. bengalensis bengalensis, were found in peninsular Malaysia (West Malaysia) based on morphological and molecular genetic analyses. This study is the first record of A. marmorata in peninsular Malaysia confirmed by both morphological and molecular genetic analyses. The present study also suggests that accurate tropical eel species identification is difficult by morphological identification alone; therefore, molecular genetic analysis is needed for precise species confirmation.
THREE Universiti Sains Malaysia (USM) students from the School of Chemical Engineering have been ... more THREE Universiti Sains Malaysia (USM) students from the School of Chemical Engineering have been honoured with the best innovation award in the recently concluded R e s e a r c h a n d I n n o v a t i o n Competition (NRIC) 2014 through their unique innovation of water treatment from natural resources. Leslie Ewe Fang Jun, Muhammad Zamani Zakaria and Vjayan Thrumakunasagran came up with an innovation known as the Natural Biodegradable and Non-toxic Coagulant or a form of water treatment using natural substances extracted from dragon fruit trees. Vjayan said that most water treatment processing industries normally use chemicals such as aluminum sulphate (alum) and polyaluminium chloride (PAC) to treat dirty and contaminated wastewater. He said that the massive scale and long-term usage of the chemicals will contribute to health problems, for example, it may cause Alzheimer or neuron diseases such as a pre-senile dementia. " Therefore, we have conducted a study and found that dra...
The mud crab (Scylla) is a commercially important crustacean, as there is a large demand in many ... more The mud crab (Scylla) is a commercially important crustacean, as there is a large demand in many Southeast Asian countries. Currently, one of the main bottlenecks to the expansion of Scylla aquaculture is the inconsistent and low production of hatchery juveniles. One major challenge to overcome at the hatchery level is disease issues caused by bacteria. The use of probiotics to outcompete pathogenic bacteria is being tested in the industry as a better disease prevention method in Scylla aquaculture compared to antibiotics, and is getting more recognition in aquaculture to reduce bacterial issues. The current review discusses mudcrab farming activities in Malaysia and the scope for using probiotics in Scylla aquaculture, as this is a potential way to increase survival rates in a long term sustainable way.
The mud crabs, belonging to the genus Scylla, are commercially important crustaceans. However, on... more The mud crabs, belonging to the genus Scylla, are commercially important crustaceans. However, one of the major obstacles to the growth of Scylla aquaculture is the low supply of hatchery produced seed due to bacterial disease issues. Currently, antibiotics are used extensively in mud crab larval rearing to improve survival. However, the long term use of antibiotics poses numerous risks. The use of probiotics in crab larval culture can provide a long term solution to this problem. A berried female Scylla parammamosain broodstock was reared in an incubation tank till the eggs hatched. For the present test, larvae were given no probiotics (control) compared to larvae with commercial Bacillus probiotic added into the culture water (10 3 and 10 4 cfu/ ml daily). During the experiment, survival, yellow and green Vibrio colony counts, water quality, larvae stage index, and the percentage metamorphosized into the Z5 stage were monitored. There was a significantly higher survival rate in th...
In Malaysia, the growing interest in farming of the mud crab is hampered by supply of hatchery re... more In Malaysia, the growing interest in farming of the mud crab is hampered by supply of hatchery reared juveniles.
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