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The objective of this study was to identify insects species visiting decomposing rabbit carrion and to establish the relationship between insects and decomposing carrion which may be of forensic importance in Jos, Plateau state Nigeria. Six rabbit weighing between 2.3kg and 2.7kg were killed by a sharp blow with a blunt metal object on the heads. Two each of the six rabbit were exposed to the sun, under shade and near river. The carcasses were allowed to decompose and insect were collected twice a day for the first one week and thereafter once a day up to the end of the 15 weeks. Four decomposition stages recorded were fresh, bloating, decay and post decay stages. A total of 16 insect species from 7 families and 3 orders were observed. Three Diptera families (Calliphoridae, Muscidae and Sarcophagidae) were identified from carcasses in all the locations and they were the first to be observed. Species collected included Lucilia Cuprina, Chrymosya albiceps, Chrymosya megacephala, Phormiaregina, Musca domestica and Hydrotaea sp. Three Coleopteran families (Cleridae, Silphidae and Dermestidae) were identified from all the carcasses and the observed species were Necrobia rufipes, Necrophile rufithorax and Dermestes muculatus. Hymenoptera (Formicidae) was also present throughout the period. The study shows that insects from the order Diptera (Calliphoridae and Muscidae) indicate the fresh and bloat stage, while the order Coleopteran (Dermestidae) indicate the decay and post decay stage during period of decomposition of the carcasses and could be of importance for further forensic studies since they were collected from the carcasses.

In Nigeria, maize serves as a staple food and a good source of carbohydrates, protein, vitamin B and minerals, hence, the need to protect it against Sitophilus zeamais. This study was conducted to determine the phytochemical properties and insecticidal potentials of Allium sativum bulb and bulb coat powders against Sitophilus zeamais. Allium sativum bulb and bulb coat were collected, dried, and pulverized into fine powder. A 0, 2.0, 3.0, 4.0, and 5.0g of the plant powder were used. Each treatment had 16 newly emerged maize weevils. The weevils were mixed with 250g un-infested maize grains in 500ml bottles and kept at room temperature. Mortality was observed for 7 days at 24 hours intervals post treatment. The experiment was laid out in a Completely Randomized Design and treatments were replicated three times. Data obtained were analyzed using a one-way ANOVA and means were separated using Duncan multiple Range test. The results revealed that both parts showed significant percentage mortality (P ≤ 0.05). The results showed that as the dosage of the bulb powder increased from 2 - 5g, percentage mortality increased from 16-32.8%. For bulb coat powder, percentage mortality increased from 16.5-32.1%. The control showed mortality of 3.0 and 2.8% for the bulb and bulb coat powders, which were significantly different (P < 0.05) from the mortality in treated maize. The most effective dosage for both powders is 5g. Based on the results obtained, Garlic bulb and garlic bulb coat could be used in the management of Sitophilus zeamais infestation.

Fish losses to Dermestes maculatus infestation is one of the biggest problems of fish farming, hence this study was carried out to evaluate the efficacy of Cymbopogon citratus against Dermestes maculatus fed on smoke-dried Catfish. Fresh and Dermestes maculatus infested samples of Catfish were procured. The fresh Catfish were smoked traditionally and then oven dried at 60°C for 1hour to remove excess moisture. Twenty-eight of un-infested Catfish were placed in 1000mL plastic jars and Cymbopogon citratus powder was added at the rate of 2.5g, 5.0g, 7.5g, and 10.0g. The fish and the powder were thoroughly mixed and six newly emerged adults were introduced into each jar, while to a different set of experiment, six 3rd-4th instar larvae of Dermestes maculatus were introduced into each jars and then covered with muslin cloth. The experiments were arranged in a Completely Randomized Design with each treatment replicated three times. Data on mortality of the larval Demestes maculatus was collected for 21 days while data on adult mortality was collected for 7 days at 48 hours interval. The data were subjected to ANOVA and means were separated using Duncan multiple range test. Cymbopogon citratus powder showed significant effects on Dermestes maculatus larvae and adult, where the highest mortality was recorded at the following doses of 2.5 and 5.0g (72.2% and77.8% respectively) for the larvae and 5.0 and 10.0g (22.2% and 16.7%) for the adults. This study revealed that Cymbopogon citratus has insecticidal potentials and therefore, be used to preserve Catfish shelve life.