1.Development of a Forensically Important Fly, Megaselia scalaris (Loew) (Diptera: Phoridae) on Cow’s Liver and Various Agar-based Diets
Raja Muhammad Zuha ; Supriyani Mustamin ; Balkhis Bashuri ; Nazni Wasi Ahmad ; Baharudin Omar
Malaysian Journal of Health Sciences 2012;10(2):49-52
In forensic entomology practice, it is more common to use raw animal tissue to breed dipteran larvae and it often
brings unpleasant odour in the laboratory. Few studies suggested the use of synthetic diets, mainly agar-based media,
as alternatives to animal tissue but it is rarely being practiced in forensic entomology laboratory. The present study
observed the growth of a forensically important fly, Megaselia scalaris (Loew) on raw cow’s liver, nutrient agar, casein
agar and cow’s liver agar. A total of 100 M. scalaris eggs were transferred each into the different media and placed in an
incubator at 30°C in a continuous dark condition. Data on length and developmental period were collected by randomly
sampling three of the largest larvae from each rearing media, twice a day at 0900 and 1500 hours until pupariation. M.
scalaris larvae reared on raw cow’s liver recorded the highest mean length (4.23 ± 1.96 mm) followed by cow’s liver
agar (3.79 ± 1.62 mm), casein agar (3.14 ± 1.16 mm) and nutrient agar (3.09 ± 1.11 mm). Larval length in raw liver and
liver agar were significantly different from those in nutrient and casein agar (p < 0.05). Larvae bred in liver agar and
raw liver recorded the shortest larval duration before entering the post-feeding stage (89 hours), followed by nutrient
agar (119 hours) and casein agar (184 hours). Total developmental time from oviposition until adult emergence for
M. scalaris in liver agar and raw liver was approximately 163 hours. All puparia in nutrient agar and casein agar failed
to hatch. This research highlighted the potential use of cow’s liver agar as an alternative diet of raw liver to culture
M. scalaris in laboratory.
2.Insecticide resistance development in Culex quinquefasciatus (Say), Aedes aegypti (L.) and Aedes albopictus (Skuse) larvae against malathion, permethrin and temephos.
Hidayati Hamdan ; Mohd Sofian-Azirun ; Wasi Ahmad Nazni ; Han Lim Lee
Tropical biomedicine 2005;22(1):45-52
Laboratory-bred females of Culex quinquefasciatus, Aedes aegypti and Aedes albopictus from the insectarium, Unit of Medical Entomology, Institute for Medical Research were used in the experiment. The late third stage of the F0 larvae which survived the high selection pressure of malathion, permethrin and temephos were reared and colonies were established from adults that emerged. Cx. quinquefasciatus larvae were subjected to selection by malathion and permethrin for 40 generations, Ae. aegypti larvae to malathion, permethrin and temephos for 32 generations and Ae. albopictus larvae were selected against malathion and permethrin for 32 generations and 20 generations against temephos. The rate of resistance development was measured by LC50 value. Cx. quinquefasciatus larvae developed higher resistance to malathion and permethrin compared to Ae. aegypti and Ae. albopictus. On the whole, permethrin resistance developed at a faster rate than malathion and temephos.
Permethrin
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Malathion
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Cancer resistance to treatment
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Aedes aegypti
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Aedes albopictus
3.Effectiveness of bone cleaning process using chemical and entomology approaches: time and cost
Lai Poh Soon ; Khoo Lay See ; Mohd Hilmi Saidin ; Ahmad Hafizam Hasmi ; Mohd Shah Mahmood ; Nurliza Abdullah ; Nazni Wasi Ahmad
The Malaysian Journal of Pathology 2015;37(2):123-135
Skeletal examination is an important aspect of forensic pathology practice, requiring effective bone
cleaning with minimal artefact. This study was conducted to compare between chemical and entomology
methods of bone cleaning. Ten subjects between 20 and 40 years old who underwent uncomplicated
medico-legal autopsies at the Institute of Forensic Medicine Malaysia were randomly chosen for this
descriptive cross sectional study. The sternum bone was divided into 4 parts, each part subjected to
a different cleaning method, being two chemical approaches i.e. laundry detergent and a combination
of 6% hydrogen peroxide and powder sodium bicarbonate and two entomology approaches using
2nd instar maggots of Chrysomyia rufifacies and Ophyra spinigera. A scoring system for grading the
outcome of cleaning was used. The effectiveness of the methods was evaluated based on average
weight reduction per day and median number of days to achieve the average score of less than 1.5
within 12 days of the bone cleaning process. Using maggots was the most time-effective and costeffective
method, achieving an average weight reduction of 1.4 gm per day, a median of 11.3 days
to achieve the desired score and an average cost of MYR 4.10 per case to reach the desired score
within 12 days. This conclusion was supported by blind validation by forensic specialists achieving
a 77.8% preference for maggots. Emission scanning electron microscopy evaluation also revealed
that maggots especially Chrysomyia rufifacies preserved the original condition of the bones better
allowing improved elucidation of bone injuries in future real cases.
4.Molecular identification of blow flies recovered from human cadavers during crime scene investigations in Malaysia.
Kavitha, Rajagopal ; Nazni, Wasi Ahmad ; Tan, Tian Chye ; Lee, Han Lim ; Isa, Mohd Noor Mat ; Azirun, Mohd Sofian
The Malaysian Journal of Pathology 2012;34(2):127-32
Forensic entomology applies knowledge about insects associated with decedent in crime scene investigation. It is possible to calculate a minimum postmortem interval (PMI) by determining the age and species of the oldest blow fly larvae feeding on decedent. This study was conducted in Malaysia to identify maggot specimens collected during crime scene investigations. The usefulness of the molecular and morphological approach in species identifications was evaluated in 10 morphologically identified blow fly larvae sampled from 10 different crime scenes in Malaysia. The molecular identification method involved the sequencing of a total length of 2.2 kilo base pairs encompassing the 'barcode' fragments of the mitochondrial cytochrome oxidase I (COI), cytochrome oxidase II (COII) and t-RNA leucine genes. Phylogenetic analyses confirmed the presence of Chrysomya megacephala, Chrysomya rufifacies and Chrysomya nigripes. In addition, one unidentified blow fly species was found based on phylogenetic tree analysis.
5.Dengue vector surveillance in urban residential and settlement areas in Selangor, Malaysia.
Chee Dhang Chen ; Seleena Benjamin ; Mohd Masri Saranum ; Yee Fook Chiang ; Han Lim Lee ; Wasi Ahmad Nazni ; Mohd Sofian-Azirun
Tropical biomedicine 2005;22(1):39-43
Ovitrap surveillance was conducted in two urban residential areas (Taman Samudera Timur and Taman Samudera Selatan) and in a settlement area (Kampung Banjar), which is located 16 km from Kuala Lumpur city center, Malaysia. In Taman Samudera, dengue cases were reported monthly in 2003/2004. Thus, a study was initiated to determine the distribution and abundance of dengue vectors, Aedes aegypti and Ae. albopictus. The ovitrap surveillance indicated that Ae. aegypti and Ae. albopictus were present both indoors and outdoors. The residential sites had 73 - 79% of the ovitraps with just Ae. aegypti population and Kg. Banjar had 56% of the ovitraps with just Ae. aegypti. In the indoor and outdoor of the residential areas, together with the settlement area, the Ae. aegypti density was significantly more than Ae. albopictus (p < 0.05) by 3 - 50 folds. There was no significant difference in the larval numbers of Ae. aegypti between indoors and outdoors (p > 0.05), thus implicating that adult gravid female Ae. aegypti are present both indoors and outdoors and they do oviposit indoors and outdoors. Ae. aegypti can be incriminated as the principal dengue vector in the urban residential site, Taman Samudera and in the settlement area, Kg. Banjar.
Dengue
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legal surveillance
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Malaysia
;
lower case pea
;
Distributing
6.Molecular identification of blow flies recovered from human cadavers during crime scene investigations in Malaysia
Rajagopal Kavitha ; Wasi Ahmad Nazni ; Tian Chye Tan ; Han Lim Lee ; Mohd Noor Mat Isa ; Mohd Sofian Azirun
The Malaysian Journal of Pathology 2012;34(2):127-132
Forensic entomology applies knowledge about insects associated with decedent in crime scene
investigation. It is possible to calculate a minimum postmortem interval (PMI) by determining the age
and species of the oldest blow fly larvae feeding on decedent. This study was conducted in Malaysia
to identify maggot specimens collected during crime scene investigations. The usefulness of the
molecular and morphological approach in species identifications was evaluated in 10 morphologically
identifi ed blow fl y larvae sampled from 10 different crime scenes in Malaysia. The molecular
identifi cation method involved the sequencing of a total length of 2.2 kilo base pairs encompassing
the ‘barcode’ fragments of the mitochondrial cytochrome oxidase I (COI), cytochrome oxidase II
(COII) and t-RNA leucine genes. Phylogenetic analyses confi rmed the presence of Chrysomya megacephala, Chrysomya rufifacies and Chrysomya nigripes. In addition, one unidentified blow fly species was found based on phylogenetic tree analysis.
7.First report of the signal fly, Scholastes sp. (Diptera:Platystomatidae) visiting animal carcasses in Malaysia.
Chen Chee Dhang ; Chong Chin Heo ; David McAlpine ; Hiromu Kurahashi ; Nazni Wasi Ahmad ; Abdullah Marwi Mohamad ; John Jeffery ; Lee Han Lim ; Baharudin Omar ; Mohd Sofian-Azirun
Tropical biomedicine 2008;25(3):264-6
Signal fly, Scholastes sp. (Diptera: Platystomatidae) was observed associated with animal carcasses in Malaysia. The first observation was on a monkey carcass, which was killed by using a handgun and immediately placed in a forested area in Gombak, Selangor while the second observation was on a pig that died of natural causes and whose carcass was placed in an oil palm plantation in Tanjung Sepat, Selangor. Both animal carcasses were visited by Scholastes sp. flies during the fresh decomposition period. However, the role Scholastes flies in the decomposition process remains unknown. In this paper, we report the occurrence of Scholastes sp. on animal carcasses in Malaysia for the first time.
Diptera
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Animals
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Malaysia
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Patient observation
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First
8.Comparative insect fauna succession on indoor and outdoor monkey carrions in a semi-forested area in Malaysia
Ahmad Wasi Nazni ; Lim Han Lee ; Dhang Chee Chen ; Chin Chong Heo ; AG Abdullah ; Mustaffa Wan Wan-Norjuliana ; Kian Wai Chew ; Jeffery John ; Hashim Rosli ; Azirun Mohd Sofian
Asian Pacific Journal of Tropical Biomedicine 2011;(z2):232-238
Objective: To study the occurrence of insects fauna obtained in a semi forested area in Malaysia using the carcass of the monkey Macaca fascicularis, Raffles, and to compared the wave of insect succession collected from the carcass placed outdoor and indoor. Methods:The outdoor and indoor studies were conducted at a location of 3o17’57.86”N, 101o47’00.78”E. The euthanized monkeys were placed indoor and outdor. The insect seccession visited the carcass, the envirenmental temperature and relative humidity were recorded. Results:The main insects attracted to specific stages of decomposition were mainly members of Diptera and Coleoptera. There was a delay of fly arrival by two days in indoor carcass. Nocturnal oviposition behaviour was not observed in this study. The flies left the carcass during the twilight zone as noted during a 3 days observation period in outdoor study. The dipteran species found outdoor and indoor were similar but more diverse coleopteran species was found indoor. Conclusions:Information and evidence from this study can be used to improve the estimation of the post mortem interval in forensic cases.