Entomologi forensik dapat ditakrifkan sebagai pengetahuan mengenai serangga yang berkait rapat dengan bangkai terutamanya manusia, dengan tujuan ia dapat digunakan dalam penentuan jangka masa pascakematian. Jangka masa pascakematian (PMI) dapat ditentukan dengan mengambil kira spesies serangga dan peringkat perkembangan setiap spesies tersebut. Oleh kerana penentuan jenis spesies memerlukan serangga berkembang ke peringkat dewasa dan ini mengambil masa yang lama, maka objektif utama kajian ini adalah untuk mengoptimumkan suhu dan kelembapan terhadap perkembangan serangga dengan menggunakan larva Chrysomya megacephala sebagai spesimen. Larva C. megacephala dipindahkan ke dalam bekas khas, kemudiannya dimasukkan ke dalam pengeram yang telah dilaraskan suhunya kepada 27, 30, 33, 36 dan 39°C. Selepas menentukan suhu optimum perkembangan larva, aras kelembapan relatif ditentukan. Ini dilakukan dengan menentukan tempoh masa yang diperlukan untuk mengembangkan telur C. megacephala hingga ke peringkat dewasa. Untuk itu aras kelembapan relatif dalam pengeram tersebut dilaraskan kepada 54.2, 57.6, 76.0 dan 67.5% (kawalan). Peringkat perkembangan C. megacephala direkodkan. Hasil yang diperolehi menunjukkan perkembangan C. megacephala lebih pantas pada suhu 33oC berbanding suhu-suhu lain yang digunakan. Aras kelembapan relatif yang optimum juga telah dikenal pasti iaitu pada 76.0%. Dengan menggunakan keduadua data didapati keseluruhan peringkat perkembangan C. megacephala iaitu daripada peringkat telur hingga dewasa dapat dipendekkan daripada 8 hingga 9 hari kepada 5 hari.
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.
This study was conducted to examine the effect of malathion on the development of Chrysomya megacephala. A total of 12 adult Sprague-Dawley rats was divided into 4 groups. Each animal in the 4 groups was given orally 0 (control), 10, 25 and 50ml/kg body weight of malathion, respectively. Chrysomya megacephala larvae were then allowed to grow on the liver of carcass. Larvae development was estimated by means of weight and length, time of adult emergence and survival rate. Results indicated that for the first 6 to 30 hours, larvae from control group developed more rapidly than larvae feeding on tissue containing malathion. However, the 3 doses of malathion did not exhibit significant impact on larvae length and weight. The time required for adult emergence was significantly greater for malathion-treated colony which was 10 days compared to 7 days in control colony. Control larvae of C. megacephala had higher survival rate compared to larvae exposed to the three different doses of malathion. Analysis of the tissues indicated that all rats and fly samples were positive for malathion. Malathion concentration was highest in liver. It was concluded that the presence of malathion altered the development rate of C. megacephala and thus disrupted normal postmortem interval estimation.