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Sep 2024 DOI 10.14302/issn.2694-2275.jzr-24-5256
O. Henderson JeffreyCorresponding author
Stimulating precocious metamorphosis in anuran larvae is an important pedagogical tool for understanding vertebrate development. However, historically, artificially provoking metamorphosis by immersing tadpoles in exogenous inducing agents (e.g., thyroxine, and iodine) compromises the longevity of the experimental animals, resulting in up to 100% mortality within a week. In our undergraduate teaching lab, we house our experimental tadpoles in circular glass dishes having a surface area of 182 cm2. Over the past four academic years this lab was performed, we observed 100% mortality of experimental animals within 10, 12, or 15 days when treated with 10-5 M, 10-6 M, or 10-7 M thyroxine, respectively. Here, we investigated whether increasing the surface area to 413 cm2 using square glass dishes would reduce the mortality of the treated animals. Omnibus Kaplan-Meier survival analysis demonstrates a statistically significant decrease in mortality in tadpoles reared in the larger square dishes compared to those housed in the smaller round dishes (P < 0.05). However, increasing the surface area of our reaction vessels could not rescue survivability of those tadpoles immersed in thyroxine, but did increase survivability of control tadpoles maintained in pond water (P < 0.01), tadpoles subjected to iodine (P < 0.05) or treated with actinomycin D (P < 0.05). These data demonstrate that increasing available reaction vessel surface area reduces overall tadpole mortality during chemically modified metamorphosis in an undergraduate teaching lab setting.
Mar 2022 DOI 10.14302/issn.2690-4837.ijip-22-4080
O AmaewhuleCorresponding author
Department of Paediatrics, University of Port Harcourt Teaching Hospital. Nigeria.
Myiasis is a parasitic infestation of the body of a mammal caused by Cordylobia Anthropophaga (Tumbu fly) larvae. The infestation is prevalent in Sub-Saharan Africa, South-East Mexico and Central America. It is usually seen among rural dwellers and has no age or sex predilection. We report a case of Tumbu fly myiasis seen in a 7month-old male living in Port Harcourt, Nigeria who was erroneously thought to have bullous impetigo.
Jul 2020 DOI 10.14302/issn.2691-6622.ijar-20-3490
Nsangou Amidou KpoumieCorresponding author
Department of Animal Sciences, University of Dschang, Cameroon
Zooplankton production and growth performance of post-larvae of common carp according to the level and frequency of fertilization with chicken droppings were studied between May and October 2017 at the IRAD pisciculture station in Foumban. To this end, two doses of hen droppings, namely 450 g/m3 (D450) and 600 g/m3 (D600), were each applied at two application frequencies (weekly (F2) and bimonthly (F1)). Thus, 1200 post-carp larvae were distributed in 12 identical concrete tanks (1.2m x 0.75m x 1m) each filled with 400 liters of water. The 2 doses applied at 2 frequencies were applied randomly in the 12 tanks in a complete random device comprising 3 treatments and 2 repetitions. Six days after fertilization, each tank was sown with zooplankton at a density of 7 individuals per liter (ind/l). The loading was carried out 12 days after fertilization at a density of 100 ind/m2. The results show that regardless of the dose and the frequency of droppings applied, the production of zooplankton was optimal 10 to 12 days after fertilization. Considering the growth performance, the tanks receiving the 600 g/m3 dose every 2 weeks presented the highest significant values (p <0.05). On the other hand, the survival rate (36% on average) was not significantly influenced (p˃0.05) by the dose and the frequency of fertilization. The 600 g/m3 dose applied every two weeks can be recommended for the rearing of post-larvae common carp.
Mar 2020 DOI 10.14302/issn.2691-3208.ijli-20-3268
Radwan EHCorresponding author
Damanhour University, Faculty of Science, Zoology department, Egypt
Pesticides are the major source of concern as water pollutants. Chlorpyrifos (CPY) (O,O-diethyl-O-(3,5,6-trichloro-2-pyridinyl) phosphorothioate; CAS No. 2921-88-2). CPY is a widely used organophosphate insecticide. The aim of current study was to determine the effects of CPY on the second instar larvae of Culex mosquito as a bio-indicator of water pollution. Levels of CPY in stream water was evaluated. Toxicity of CPY was estimated on mosquito. Along with the evaluation of effects of water polluted with CPY on mosquito to predict the water pollution levels. Results showed that LC95 of CPY was 6331.30 mg/kg after 24hr and increased to 230506.4 ppm after 48hr of exposure. It was noted that the activity of CPY is concentration and time dependent. The 0.09 ppm concentration of CPY (the amount that was found in the stream water) had no effect on the second instar Culex larvae similar to the control (tap water). There is no effect after 72,96h of exposure of the population to the detected insecticide. It could be concluded that mosquito is not a bioindicator of CPY pollution at the detected level in stream water.
Oct 2019
Radwan EHCorresponding author
Department of Zoology, Faculty of Science, Damanhour University, Egypt.
Pesticides are the major source of concern as water pollutants. Persistent organochlorines can accumulate in food chains. Chlorpyrifos (O,O -diethyl O -(3,5,6-trichloro-2-pyridinyl) phosphorothioate; CAS No. 2921-88-2; CPY). CPY is a widely used organophosphorus insecticide that is available in a granular formulation for treatment in soil. Pesticides are used to control a wide range of pests including Mosquitoes. Mosquito borne diseases infect millions of people every year globally. The aim of current study was to screen the fresh water pollutants, water quality parameter in irrigation water from El Mahmodia stream, El-Beheira Governorate, Egypt and to determine the adverse effects of Chlorpyrifos on the larvae of Culex mosquito larvae as bio-indicator. The LC95 of Chloropyrifos insecticide was 6331.30 at 24h and increased to 230506.4 after 48h of exposure to the Chloropyrifos insecticide. It is noted that the effect of the exposure time of Chloropyrifos insecticide on the LC50, LC25 and LC95 values had a synergistic interaction with time, as it increased after 48h of exposure when compared to 24 h of exposure. The 0.09 ppm concentration of Chloropyrifos had no effect on the second instar Culex larvae, as there is no mortality over time; the same result is also with the control 0 ppm. There is no effect after 72, 96h of exposure of the population to the detected insecticide. This study concerns with studying the pollutants along El Mahmodia stream in El Beheira governorate in Abo Homs city with its abundance during the four seasons (2016-2017), as well as studding the physicochemical parameters in it. Another concern of this study is estimating the effect of one of this pesticides (Chloropyrifos) insecticide on the second instar Culex mosquito larvae, determining the lethal concentration of this insecticide on the Culex larvae. Along the study area, pesticides are used within a high ratio on the agriculture scale with its four main categories organophosphates, organochlorine, pyrthoid and carbamates. Organophosphates and organochlorine are used at a wide range. Pollutants measuring achieved by using GC-MS as water samples collected seasonally and analyzed, there is a big number of Pollutants which was found as well as other compounds which are banned, such as DDT. The physicochemical parameters Turbidity, COD, BOD in El Mahmodia stream exceeded the desirable limits of (Egyptian Law 48/1982), (WHO, 1993) and (FAO, 1985) although the other parameters as EC, PH, DO,TDS TSS are to be within the permeable limits. HCO3, NH4. Cu also was found to exceed the desirable limits while, Pb, Mn, Fe and Cd within the permeable limits. Chloropyrfos as an organophosphate pesticide used in the present study which was found with 0.09 mg/l in the stream water, used to estimate its effect on the Culex mortality, determining LC25, LC50 and LC95. The experiment continued for 96 h but after 48 h there is no effect of Chloropyrfos on Culex larvae. The experiment began with 20 second instar Culex larvae immersed in 100 ppm, 10 ppm, 1 ppm, 0.1 ppm and finally 0.09 ppm of Chloropyrfos insecticide with five repeats to each concentration, it is noted that the lethal concentration increase after 48h of experiment, the larval mortality decrease with time.
Sep 2022 DOI 10.14302/issn.2639-3166.jar-22-4247
Haroun Mohamed Adam AbubakerCorresponding author
Department of Crop Science, College of Agriculture, University of Bahri- Sudan.
The greater wax moth considered one of the most worldwide-spread pests of the bee wax. This Study was designed to investigate the insecticidal activity of Carumcarvi, Eculaptus camaldulensis and Nigella sativa against 3rd larval instar of G.mellonellathrough laboratory screening. Five concentrations (5%, 7.5%, 10%, 12.5% and 15%) of each plant extract were used in this experiment. Mortality (%) was recorded after 24, 48, 72 and 96 hrs post treatment. The results showed C. carvi, E. camaldulensis and N.sativahave insecticidal activity against 3rd_ instar larvae of G. mellonella. The highest concentration (15%) caused 90% ,86.7% and 80% larval mortality after 96 hrs for C. carvi,E. camaldulensis and N.sativarespectively. The statistical analysis revealed that there is a significant difference (p< .001) between all treatments and control. The results also clearly demonstrate that the C. carvi are significantly more toxic than E. camaldulensis and N. sativa, whereas the LC50 values were 5.4% forC. carvi,6.0% for E. camaldulensis and 6.2% for N. sativa.
Jun 2021 DOI 10.14302/issn.2639-3166.jar-21-3857
Mohamed Adam AbubakerHarounCorresponding author
Department of Crop Science, College of Agriculture, University of Bahri-Sudan.
The Fall armyworm worm (FAW) (Spodopterafrugiperda) is one of the important economic pests which goes on several field crops and causes serious damage. The aim of this study was to look for efficient, less cost and environmentally friend plant extract for controlling Fall armyworm worm in cereal crops. A Complete Randomized Block Design (CRBD) experiments with three replications were conducted in the laboratory to investigate the insecticidal effects of four plant extracts consisting of ethanolic extract of Neem (Azadirachta indica) seeds, Black pepper (Piper nigrum) seeds, Usher (Calotropis procera ) leaves and water extracts of Argel (Solenostemma argel) leaves on larvae of the Fall armyworm (FAW) (Spodoptera frugiperda). Newly emerged larvae of FAW were treated topically by 4 concentrations (10, 25, 50 and 75%) of each extract, and then the larval mortalities were calculated after 24, 48 and72 hrs. The results showed the highest concentrations (75%) of the three ethanolic extracts gave higher mortality percentages (100%) after 72 hrs of exposure, compared with other concentrations. Also, these were not significantly different from the recommended dose of the standard pesticide “Spinosad”. On the other hand, Argel water extract showed no effect on the (FAW) larvae. It is recommended that this experiment to be replicated under different environments.
Jun 2021 DOI 10.14302/issn.2639-3166.jar-21-3816
Elamin Elhaj WaleedCorresponding author
Department of Plant Protection, College of Agricultural Studies, Sudan University of Science and Technology, Khartoum State, Sudan.
African bollwormis a worldwide-spread species that shows a high degree of polyphagia and it is considered as one of the main agricultural pests in the world. Laboratory experiments were conducted in the Research Laboratory, College of Agricultural Studies, Sudan University of Science and Technology to evaluate the lethal effect of C. rotundusand D. stramonium on the H. armigeraand to investigate the synergistic effect of sesame oil and tested extracts by dipping methods. Five concentrations (4%, 6%, 8%, 10% and 12%) were used for each plant extract in a Completely Randomized Design. Tubers ethanolic extract of C. rotundus at 12% concentration caused 90% mortality after 72 hrs of application, whereas 12% concentration of seeds ethanolic extract of D. stramonium generate only 70% mortality after 72 hrs of exposure. When sesame oil was added to each concentration of ethanolic extract of C. rotundus and D. stramonium it exhibited a synergistic effect. In fact, the 10% concentration scored 53.3% and 76.7% mortality, however, when mixed with sesame oil the mortality increased significantly to 83.3% and 100% for D. stramonium and C. rotundus respectively after 72 hrs of exposure. This study clearly demonstrates that both tested plants have a lethal effect on the larvae of the African bollworm. However, tubers ethanolic extract of C. rotundus seems to be significantly more toxic than the seeds ethanolic extract of D. stramonium. This study also revealed that sesame oil has a synergistic effect when added to these plant extracts.
Jun 2021 DOI 10.14302/issn.2639-3166.jar-21-3817
Elamin Elhaj WaleedCorresponding author
Department of Plant Protection, College of Agricultural Studies, Sudan University of Science and Technology, Khartoum State, Sudan.
Helicoverpaarmigera is one of the most destructive pests of field crops worldwide. The Study was designed to investigate through laboratory screening the insecticidal activity of Ricinus communis, Cassia occidentalis and Bacillus thuringiensis var. Kurstaki (Btk) and their combinations against 2nd larval instar of H. armigera. Five concentrations (4%, 6%, 8%, 10% and 12%) of each plant extract and (0.62, 1.25, 2.5, 5, and 10 mg/ml) of Bt were used in this experiment. Mortality (%) was recorded after 24,48,72 and 96 hrs post treatment. The results showed that R. communis, C. occidentalis and Btkhave insecticidal activity against 2nd instar larvae of H. armigera. The highest concentration (12%) caused 80% and 70% larval mortality after 96 hrs for R. communis and C. occidental respectively. The statistical analysis revealed that there is a significant differences between all treatments and control. Additionally, all combinations (plant/plant or plant/Bt) increased the mortality %. The results also clearly demonstrate that the R. communis are significantly more toxic than C. occidental where the LC50 values were 6.4 % for R. communis and 8.1% for C. occidental. On the other hand LC50 value for Bt was 0.41 mg/ml. The binary mixture of R. communis and C. occidental have a potentiation effect after 48 hrs. Regarding the mixture of Bt and plant extracts the results revealed that R. communis and Bt mixture induced a potentiation effect whereas C. occidental and Bt mixture induced a an additive effects.
Nov 2020 DOI 10.14302/issn.2691-6622.ijar-20-3605
Nsangou Amidou KpoumieCorresponding author
Department of Animal Sciences, University of Dschang, Cameroon
In order to contribute to the domestication of Labeobabusbatesii, the survival and growth performances in pre-grossing according to the dietary protein level were studied between January and April 2020. A total of 400 fry (0.8 ± 0.02g), divided into four batches and distributed randomly in 8 happas (50 ind / m2), respectively received in duplicate the food at 25, 30, 35 or 40% crude protein (R25%, R30%, R35% and R40%). The results show that: survival rate and growth performances were significantly influenced (p≤0.05) by the level of dietary protein except for lengths (total, standard and length gain) whose highest values were obtained with the diet at 35% crude protein, the highest significant values of the other growth characteristics were obtained in the batch fed at 25% crude protein while the lowest were recorded on individuals of batches fed at 40% crude protein. Regardless of the level of food protein, the post-larvae presented an allometric minorant growth. So, 25% of dietary protein is therefore recommended for pre-grossing of this species.
May 2016 DOI 10.14302/issn.2372-6601.jhor-14-401
Fried BernardCorresponding author
Biology Department, Lafayette College, Easton, PA 18042.
The hemocyte is a major immunological cell of molluscs. Much of the immunological phenomena associated with molluscan immunology can be attributed to cellular immunity associated with these cells suspended in the hemolymph. These cells are often referred to as amoebocytes or hemocytes. Such cells are of great importance to immune mechanisms associated withBiomphalaria snails. The Biomphalaria snail is the main vector of the important trematode parasite Schistosoma mansoni. This is a waterborne parasite that affects about 200 million people globally and puts countless other millions at risk of infection. Larval stages of the parasite are released from the snail in tainted waters and the larval cercarial stage actively penetrates the skin of humans and other vertebrates. Larvae migrate via the venous system to vital organs associated with the heaptic portal and mesenteric blood vessels. Larvae develop into sexually mature male and female adult worms that live in major venous blood vessels. The worms mate and produce eggs that lodge in major organs such as the spleen, liver, and intestines. Eggs produce extensive granulomas that cause cirrhosis and other pathological conditions in the affected organs.