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@#In addition to the scarcity of forensic entomology baseline data on oviposition of necrophagous insects and completion of their life cycles in the Borneo region, similar data derived from caves remain unreported. Since entomological baseline data can differ from one biogeoclimatic region to another, the lack of such data would limit the practical values of applying entomological evidence in estimating minimum postmortem interval (mPMI). Therefore, this present research that investigated oviposition and completion of life cycles of necrophagous flies infesting rabbit carcasses decomposing in Mount Kapur Cave and its surrounding forest habitat in Kuching, Sarawak merits forensic consideration. In general, 13 taxa of necrophagous flies were identified viz. Hypopygiopsis violacea, Hypopygiopsis fumipennis, Hemipyrellia ligurriens, Hemipyrellia tagaliana, Chrysomya megacephala, Chrysomya villeneuvi, Chrysomya rufifacies, Chrysomya chani, Chrysomya pinguis, Chrysomya nigripes, Ophyra spinigera and Ophyra chalcogaster, as well as unidentified Sarcophagidae. In addition, Hyp. violacea and Hyp. fumipennis were the two earlier necrophagous flies that oviposited in all rabbit carcasses decomposing in both habitats. While all these necrophagous flies were observed infesting carcasses in Mount Kapur Cave, Hem. ligurriens and Hem. tagaliana were not found infesting carcasses in the surrounding forest habitat. Complete life cycles for six and five different necrophagous fly species were successfully observed in Mount Kapur Cave and its surrounding forest habitat, respectively. Significant delay in oviposition, as well as longer durations for completing the life cycles in several necrophagous fly species were observed in Mount Kapur Cave when compared with those of surrounding forest habitat (p < 0.05). These findings deserve consideration as the first ever forensic empirical baseline data on oviposition and completion of life cycles for necrophagous flies in Sarawak as well as in a cave habitat, in view of its practical values for estimating mPMI for forensic practical caseworks.
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@# The microbiological quality of thirty ready-to-eat (RTE) keropok lekor (a sausage shape Malaysian fish product) was evaluated in comparison to microbiological guidelines for ready to eat foods. The two E. coli isolates were subjected to DNA sequencing, identified and tested for their resistance towards fifteen different antibiotics. The survival and growth of the isolated E. coli strains inoculated in keropok lekor at atmospheric air and vacuum packaging were also evaluated. Results revealed that four samples (13.33%) contained Enterobacteriaceae counts that exceeded the recommended allowable counts of 4.0 log10 CFU/g. Unsatisfactory level of coliforms (> 1.7 log10 CFU/g) was also observed in ten of the samples; two of which contained E. coli (2.1 ± 0.17 and 3.7 ± 0.02 log10 CFU/g), suggesting of poor hygiene and sanitation practices. While the ‘Possible E10’ E. coli strain was observably resistant towards Nalidixic acid (30µg) alone, B10 E. coli isolate was worryingly resistant towards Ampicillin (10µg), Ceftazidime (30µg), Ciprofloxacin (5µg), Ceftriaxone (30µg), Nalidixic acid (30µg) and Tetracycline (30µg). This study also revealed that the growth and survival of the ‘Possible E10’ and B10 E. coli strains were not significantly affected by vacuum packaging when stored at both 4°C and 28°C. Therefore, intervention programmes to alert and educate smallmedium enterprisers (SMEs) of keropok lekor producers on food safety as well as potential health risks that can be associated due to inappropriate handling procedures of such product, merits consideration.
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@#Influence of citronella and chlorpyrifos on oviposition and duration for completing life cycles for Chrysomya megacephala and Chrysomya rufifacies infesting decomposing rabbit carcasses was studied. Male rabbit carcasses (n = 12) were equally divided into control, citronella- and chlorpyrifos–treated groups, and left to decompose for 14 consecutive days. C. megacephala was the first necrophagous fly oviposited in all control and citronellatreated carcasses followed by C. rufifacies. Although initial oviposition of C. megacephala was delayed (4-6 hours) in citronella-treated carcasses (P < 0.05), prolongation in completing its life cycle was not observed. Neither delayed initial oviposition nor prolonged life cycle for C. rufifacies in citronella-treated carcasses was observed. Oviposition was delayed for chlorpyrifos-treated carcasses (0.42 g/L), and eclosion of eggs remained unsuccessful. The findings deserve consideration because these chemicals are easily accessible and can be used by cunning criminals to confuse forensic entomologists while estimating minimum postmortem interval.
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Consumption of iced beverages is common in Malaysia although specific research focusing on its safety parameters such as presence of faecal coliforms and heavy metal elements remains scarce. A study conducted in Kelantan indicated that faecal coliforms were detected in the majority of the ice cube samples analyzed, largely attributable to improper handling. Hence, it was found pertinent to conduct similar study in other parts of the country such as Johor Bahru if the similar pattern prevailed. Therefore, this present crosssectional study which randomly sampled ice cubes from 30 permanent food outlets in Taman Universiti, Johor Bahru for detecting contamination by faecal coliforms and selected heavy metal elements (lead, copper, manganese and zinc) acquires significance. Faecal coliforms were detected in 11 (36.67%) of the samples, ranging between 1 CFU/100 mL to > 50 CFU/100 mL; two of the samples were grossly contaminated (>50 CFU/100 mL). Interestingly, while positive detection of lead was observed in 29 of the 30 ice cube samples (mean: 0.511±0.105 ppm; range: 0.489-0.674 ppm), copper, manganese and zinc were not detected. In addition, analysis on commercially bottled mineral water as well as in tap water samples did not detect such contaminations. Therefore, it appears that (1) contamination of faecal coliforms in ice cubes in food outlets in Malaysia may not be sporadic in pattern but rather prevalent and (2) the source of water used for manufacturing the ice cubes that contained significant amount of lead would suggest that (3) it was neither originated from the treated tap water supply nor bottled mineral water or (4) perhaps contaminated during manufacturing process. Further studies exploring the source of water used for manufacturing these ice cubes as well as the handling process among food operators deserve consideration.
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Abstract. The use of ice cubes in beverages is common among patrons of food outlets in Malaysia although its safety for human consumption remains unclear. Hence, this study was designed to determine the presence of faecal coliforms and several useful water physicochemical parameters viz. free residual chlorine concentration, turbidity and pH in ice cubes from 30 randomly selected food outlets in Kubang Kerian, Kelantan. Faecal coliforms were found in ice cubes in 16 (53%) food outlets ranging between 1 CFU/100mL to >50 CFU/ 100mL, while in the remaining 14 (47%) food outlets, in samples of tap water as well as in commercially bottled drinking water, faecal coliforms were not detected. The highest faecal coliform counts of >50 CFU/100mL were observed in 3 (10%) food outlets followed by 11-50 CFU/100mL and 1-10 CFU/100mL in 7 (23%) and 6 (20%) food outlets, respectively. All samples recorded low free residual chlorine concentration (<0.10mg/L) with the pH ranging between 5.5 and 7.3 and turbidity between 0.14-1.76 NTU. Since contamination by faecal coliforms was not detected in 47% of the samples, tap water and commercially bottled drinking water, it was concluded that (1) contamination by faecal coliforms may occur due to improper handling of ice cubes at the food outlets or (2) they may not be the water sources used for making ice cubes. Since low free residual chlorine concentrations were observed (<0.10mg/L) in all samples as well as in both tap water and commercially bottled drinking water, with the pH ranged between 5.5-7.3, ineffective disinfection of water source as a contributing factor to such high counts of faecal coliforms in ice cubes also could not be ruled out. Therefore, a periodical, yet comprehensive check on the food outlets, including that of ice cube is crucial in ensuring better food and water for human consumption.
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Abstract. The use of Chrysomya megacephala larvae for detecting malathion for diagnosing the cause of death was investigated. This could prove useful when the visceral organs have become liquefied during decomposition and therefore cannot be sampled. A field experiment was conducted in which C. megacephala were allowed to colonise naturally the corpses of rabbits that had died of malathion poisoning. The concentration of malathion increased gradually during the larval stages of C. megacephala reaching the maximum concentration in the third instar larvae. The concentration of malathion declined during prepupal stage and reached its lowest level among tenerals. The average malathion concentrations in C. megacephala growing in poisoned rabbit corpses left in a sunlit habitat were significantly higher (p<0.05) than those growing on poisoned rabbits left in a shaded habitat. The concentrations of malathion in the different stages of development of C. megacephala were moderately correlated (r = 0.51-0.69) with the administered doses as well as with those estimated in visceral organs. Thus, it would not be reliable to suggest the formulation of mathematical algorithms for relating the concentration of malathion found in the different stages of development of C. megacephala with those found in the visceral organs. However, in the context of forensic investigation, the qualitative detection of malathion in C. megacephala may prove useful in diagnosing the cause of death, since malathion is a common cause of accidental and suicidal deaths.