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.
Penentuan kumpulan bangsa dalam analisis rambut pada kepala adalah satu cabaran yang dihadapi dalam analisis forensik untuk mengenal pasti mangsa, suspek dan tempat kejadian jenayah. Kajian ini bertujuan untuk mengenal pasti perbezaan antara dua kaum terbesar di Malaysia iaitu Melayu dan Cina melalui penelitian ciri-ciri rambut. Ini termasuklah ciri umum rambut, corak kutikel, warna, taburan pigmen kortek dan ciri medula – jenis, ketebalan dan indeks medula. Kajian ini telah dijalankan dengan menggunakan mikroskop cahaya dan terdiri daripada lima langkah iaitu penyediaan sampel, penelitian ciri umum rambut, penyediaan dan penelitian slaid acuan corak sisik kutikel, slaid kortek serta medula. Hasil daripada kajian in mendapati bahawa kebanyakan Melayu mempunyai warna pigmen yang bercoklat gelap manakala Cina mempunyai pigmen coklat cerah. Kami juga mendapati bahawa ketebalan medula boleh juga digunakan untuk membezakan antara Melayu dan Cina di mana nilai purata bagi Melayu dan Cina masing-masing adalah 7.59 ± 1.45 μm dan 9.12 ± 1.85 μm. Nilai purata indeks medula bagi Melayu dan Cina pula adalah 0.17 ± 0.02 μm dan 0.18 ± 0.02 μm masing-masing. Walaupun begitu, ciri-ciri seperti tekstur, ketebalan rambut, corak sisik kutikel, taburan pigmen dan jenis medula pula menunjukkan perbezaan yang tidak ketara antara Melayu dan Cina. Kesimpulannya, kajian ini telah menunjukkan bahawa warna pigmen, ketebalan medula dan indeks medula adalah ciri-ciri penting yang boleh digunakan untuk menentukan bangsa.
A novel electrophoretic separation system has been successfully applied for the preparation of human sperm prior to the execution of assisted reproductive techniques (ARTs). This new system is designed to overcome the generation of reactive oxygen species (ROS) through centrifugation in conventional sperm preparation. Since the previous study showed favorable outcomes in humans, this study intends to implement this new system for animal sperm preparation particularly in bull. Fresh semen from adult bulls were used. Optimization of the electrophoretic system for optimum bull sperm separation involved different strength of voltage and separation time. The voltages applied were 10V, 20V, 30V, 40V, 50V, and 60V. For each voltage applied, the system was operated for a duration of 12 min. An average of 10 μl fractionalized semen was taken out at the collection site at every 2-min interval. Every fractionated sperm was then evaluated for percentage of viability, motility, and DNA damage assessment. Result showed that electrophoresis at 20V and 6 min yielded more than 80% viable and more than 70% motile sperm population with the lowest DNA damage. In conclusion, the system was able to fractionate high quality bull sperm at 20V and 6 min.