scholarly journals LARVICIDAL ACTIVITY OF Bacillus sphaericus 2362 AGAINST Anopheles nuneztovari, Anopheles darlingi AND Anopheles braziliensis (DIPTERA, CULICIDAE)

1999 ◽  
Vol 41 (2) ◽  
pp. 101-105 ◽  
Author(s):  
Iléa Brandão RODRIGUES ◽  
Wanderli Pedro TADEI ◽  
José Manuel Cabral da Silva DIAS
Keyword(s):  
Mortality Rate ◽  
Larvicidal Activity ◽  
Preliminary Data ◽  
Mosquito Species ◽  
Larval Instar ◽  
Bacillus Sphaericus ◽  
Anopheles Darlingi ◽  
Standard Strain ◽  
The Third ◽  
Anopheline Larvae

In this present study, preliminary data was obtained regarding the mortality rate of the Amazonian anophelines, Anopheles nuneztovari, Anopheles darlingi and Anopheles braziliensis when subjected to treatment with Bacillus sphaericus strain 2362, the WHO standard strain. Initially, experiments were conducted to test the mortality rate of the three species of anopheline larvae. The third larval instar of An. nuneztovari and the second and third larval instars of An. darlingi proved to be the least susceptible. In other experiments, the same three mosquito species were tested with the standard strain 2362, An. nuneztovari was the least susceptible to this insect pathogen, while An. braziliensis was the most susceptible. This latter species showed a difference in the level of LC50 concentration, when compared to the former, of 2.4, 2.5 and 1.8 in readings taken 24, 48 and 72 hours after exposure to the bacillus.

scholarly journals Analysis of toxicity on Bacillus sphaericus from amazonian soils to Anopheles darlingi and Culex quinquefasciatus larvae

2008 ◽  
Vol 38 (2) ◽  
pp. 255-262 ◽  
Author(s):  
Eleilza de Castro Litaiff ◽  
Wanderli Pedro Tadei ◽  
Jorge Ivan Rebelo Porto ◽  
Ila Maria de Aguiar Oliveira
Keyword(s):  
Larvicidal Activity ◽  
Culex Quinquefasciatus ◽  
Bacillus Sphaericus ◽  
Probit Analysis ◽  
Lethal Concentration ◽  
Anopheles Darlingi ◽  
Median Lethal Concentration ◽  
Standard Strain ◽  
Breeding Sites ◽  
High Effectiveness

Bioassays under laboratory conditions aiming to determine the larvicidal activity of Bacillus sphaericus were carried out on Anopheles darlingi and Culex quinquefasciatus. In order to estimate the toxicity through median lethal concentration (LC50) and the relative potency of the strains to B. sphaericus standard strain 2362, probit analysis was performed utilizing the POLO-PC program. The findings of LC50 pointed out high effectiveness on strains IB15 (0.040 ppm), IB19 and S1116 (0.048 ppm), IB16 (0.052 ppm) and S265 (0.057 ppm). Strain IB15 presented nearly 50% more potency than strain 2362 in bioassays conducted on A. darlingi. It was observed that IB16 and S1116 strains were the most powerful against C. quinquefasciatus, showing to be about 300-400% stronger than 2362 strain. The results show that laboratory conditioned evaluation can be an important way to select promising bacteria with entomopathogenic action on biolarvicides production for use on mosquitoes breeding sites.

Mosquito Species breeding in “Test” Water Containers in West Africa

1933 ◽  
Vol 24 (4) ◽  
pp. 483-491 ◽  
Author(s):  
Cornelius B. Philip
Keyword(s):  
Mosquito Species ◽  
Weather Conditions ◽  
Dense Population ◽  
Seasonal Differences ◽  
The Third ◽  
Several Variables ◽  
Test Water ◽  
Aedes Africanus ◽  
Optimum Type ◽  
Mango Leaves

Observations additional to those made by Dunn (1927) of Culicine mosquitos breeding in “ test ” water containers about a Compound in Southern Nigeria, near Lagos, are here reported for a period of the year (June to December) not covered in Dunn's study. Only the optimum type of container mentioned in Dunn's report (bamboo joints containing water and mango leaves) was employed, and these were placed in the same ten representative environmental situations. The numerical rank of infesting species differed significantly in the two studies only in the case of Culex decens, which dropped from third to last place, and of Aëdes africanus, which rose from tenth to sixth place. The total numbers of infestations in the former study were greater, but this is explainable on the basis of one or several variables, i.e., seasonal differences, elapse of time between studies, or less probably the fact that there were four containers instead of one at each station. The number of infestations at any one station has little relation to the number of resultant adults; there is a wide variation in these numbers.An analysis of the occurrence of A. aegypti in containers and a discussion of certain bionomical information together with relative weather conditions are included. Brief data are also presented of the incidence of species at three additional stations, one in a centre of dense population (Lagos), one in a suburb (Ebute Metta), and the third isolated in dense “ bush.”

The Post-embryonic Development of the Tracheal System in Drosophila melanogaster

1957 ◽  
Vol s3-98 (41) ◽  
pp. 123-150
Author(s):  
JOAN M. WHITTEN
Keyword(s):  
Drosophila Melanogaster ◽  
Adult Stage ◽  
Larval Instar ◽  
Pupal Stage ◽  
Tracheal System ◽  
True Nature ◽  
The Third ◽  
Air Sacs ◽  
Abdominal Region ◽  
Pupal Cuticle

The fate of the tracheal system is traced from the first larval instar to the adult stage. The basic larval pattern conforms to that shown for other Diptera Cyclorrhapha (Whitten, 1955), and is identical in all three instars. According to previous accounts the adult system directly replaces the larval: the larval system is partly shed, partly histolysed, and the adult system arises from imaginal cell clusters independently of the preceding larval system. In contrast, it is shown here that in the cephalic, thoracic, and anterior abdominal region there is a definite continuity in the tracheal system, from larval, through pupal to the adult stage, whereas in the posterior abdominal region the larval system is histolysed, and the adult system is independent of it in origin. Moreover, in the pupal stage this region is tracheated by tracheae arising from the anterior abdominal region and belonging to a distinct pupal system. Moulting of the tracheal linings is complete at the first and second larval ecdyses, but incomplete at the third larval-pupal and pupal-adult ecdyses. In consequence, in both pupal and adult systems there are tracheae which are secreted around preexisting tracheae, others formed as new ‘branch’ tracheae, and those which have been carried over from the previous instar. In the adult the newly formed tracheae of the posterior abdominal region fall into a fourth category. Most of the adult thoracic air sacs correspond to new ‘branch’ tracheae of other instars. The pre-pupal moult and instar are discussed with reference to the tracheal system and tentative suggestions are made concerning the true nature of the pre-pupal cuticle. There is no pre-pupal tracheal system. Events traced for Drosophila would seem to be general for Cyclorrhapha, both Acalypterae and Calypterae. The separate fates of the anterior and posterior abdom inal systems, in contrast with the straightforward development in Dipterc Nematocera, would appear to mark a distinct step in the evolution of the system in Diptera.

Neonatal Intensive Care

Curationis ◽  
1981 ◽  
Vol 4 (1) ◽  
Author(s):  
Lyn Acres
Keyword(s):  
Intensive Care ◽  
Mortality Rate ◽  
Old Age ◽  
Neonatal Intensive Care ◽  
Perinatal Period ◽  
Third Trimester ◽  
Newborn Period ◽  
The Third

THE events of the third trimester of pregnancy labour, delivery and the newborn period undoubtedly influence the whole of one’s life. Old age excluded, the highest mortality rate occurs in the perinatal period.

scholarly journals LARVICIDAL ACTIVITY OFTITHONIA DIVERSIFOLIALEAF EXTRACT ONPERI-URBAN MOSQUITO LARVEA INABAKALIKI; ALTERNATIVE TO INSECTICIDE DEVELOPMENT.

2015 ◽  
Vol 7 (1) ◽  
pp. 1225-1228
Author(s):  
UHUO CA ◽  
OKEREKE CN ◽  
NWELE ED ◽  
OGBONNA S.U ◽  
NWANCHOR K.C ◽  
...  
Keyword(s):  
Mortality Rate ◽  
Adverse Effects ◽  
Bioactive Compounds ◽  
Larvicidal Activity ◽  
Urban Areas ◽  
Insect Pests ◽  
Anopheles Mosquito ◽  
Mosquito Population ◽  
Mosquito Larvae ◽  
Dose Dependent

The bioassay activitiesofTithonia diversifolia leave extract was conducted on the larvae of Anopheles mosquito collected at peri-urban areas of Abakaliki Ebonyi State, using the concentrations of the extract in dilutions at 50/100ml, 40/100ml, 30/100ml and 20/100ml introduced with 10 Anopheles mosquito larvae each in four replicates and allowed for 3hrs. Mean mortality rate of the larvae were observed after the first hour, thus 30%, 10%, 05% and 0% respectively while in the 2nd hour were 60%, 40%, 20% and 10% and in the 3rd hour were 80%, 60%, 50% & 30% respectively. The result thus revealed that the treatment is dose dependent and that the studied specie has some bioactive compounds that can be exploited for insect pests control hence observed to be sensitive in anopheles mosquito larvae. Therefore Tithonia diversifolialeaf extract could be used as a bioassay for the control of mosquito due to its active properties as this has exhibited adverse effects on the larvae thereby reducing the mosquito population and thus reducing the malarious infection associated with the bite of mosquito.

scholarly journals THE USE OF AGENTS BASED ON THE BACTERIUM BACILLUS THURINGIENSIS VAR. ISRAELENSIS FOR MOSQUITO CONTROL

2019 ◽  
Vol 98 (8) ◽  
pp. 893-896
Author(s):  
Svetlana A. Roslavtseva
Keyword(s):  
Bacillus Thuringiensis ◽  
Aedes Aegypti ◽  
Synergistic Effect ◽  
Mosquito Control ◽  
Mosquito Species ◽  
Bacillus Sphaericus ◽  
Development Of Resistance ◽  
Blood Sucking ◽  
Low Concentrations ◽  
Bacterium Bacillus

Mosquito control is necessary to improve the epidemic and, consequently, the sanitary and hygienic situation in human settlements. At the same time, the safest and more environmentally friendly way of controlling is not the fight against adult mosquitoes, but the treatment of reservoirs with microbiological larvicides based on entomopathogenic, aerobic, spore-forming, saprophytic bacteria Bacillus thuringiensis (de Barjac) (Bti). A new serotype of the bacterium B. thuringiensis was found in Israel in the Negev desert. This serotype being more active against larvae of blood-sucking and non-blood-sucking mosquitoes and midges than previously known serotypes, was named israelensis. Bti endotoxin is a typical insecticide with intestinal type of action for different mosquito species. For example, Bti H14 is highly insecticidal to the larvae of Aedes aegypti and Ae. albopictus at very low concentrations. The parasporal body (endotoxin crystal), a crystalline protein consisted of four main polypeptides and two minor polypeptides, possesses of a larvicidal action. Larvicidal activity is associated with a synergistic effect in a combination of four polypeptides. The possibility of development of resistance to products based on Bti and Bacillus sphaericus in populations of mosquitoes (Culicidae) was investigated. The use of domestic microbiological formulations based on Bti («Baktitsid», «Larviol-pasta», and «Antinat») was shown an eradication the larvae of bloodsucking mosquitoes and midges to be possible and rational, since they are not generated resistant populations of mosquitoes. This is confirmed by more than 30 years of the use of such formulations.

scholarly journals ANÁLISIS DEL CRECIMIENTO Y LA MORTALIDAD DE ANISOTREMUS INTERRUPTUS (GILL) (PERCIFORMES: HAEMULIDAE) EN LA COSTA DE COLIMA, MÉXICO

2016 ◽  
Vol 33 ◽  
Author(s):  
Elaine Espino Barr ◽  
Manuel Gallardo Cabello ◽  
Fernando González Orozco ◽  
Arturo Garcia Boa
Keyword(s):  
Mortality Rate ◽  
Growth Parameters ◽  
Total Mortality ◽  
Condition Index ◽  
First Year ◽  
The Third ◽  
Second Year ◽  
First Year Of Life ◽  
Mortality Analysis

This paper deals with the growth and mortality analysis of the burrito grunt A n i s o t remus interru p t u s on the coast of Colima, México. The estimated growth parameters are: L¥ = 50.59 cm; W¥ = 5,051.04 g; k = 0.147 years- 1; to = -0.916 years; A0 . 9 5 = 19.46 years. Most of the growth occurred during the first year of life, when the grunt grows 12.52 cm, the second year it grows 4.95 cm and the third, 4.60 cm. The highest value of the condition index took place between February and September. The total mortality rate (Z) was calculated as 0.53 years- 1. These values are basic for the plan of administration of the fishery of this species.

scholarly journals Characteristics of mortality in the Orenburg region population in 2011-2017

2020 ◽  
Vol 5 (2) ◽  
pp. 99-104
Author(s):  
Evgenii L. Borschuk ◽  
Dmitrii N. Begun ◽  
Tatyana V. Begun
Keyword(s):  
Mortality Rate ◽  
Causes Of Death ◽  
Age Groups ◽  
Circulatory System ◽  
Mortality Rates ◽  
Female Population ◽  
Orenburg Region ◽  
The Third ◽  
Circulatory System Diseases ◽  
External Causes

Objectives - to study the mortality indicators, their dynamics and structure, in the population of the Orenburg region in the period of 2011-2017. Material and methods. The study was conducted using the data from the territorial authority of statistics in the Orenburg region in the period from 2011 to 2017. The analytical, demographic and statistical methods were implemented for the study of the demographic indicators. Results. Cities and municipal settlements of the Orenburg region with high mortality indicators were included in the second and fourth clusters during the cluster analysis. The first and third clusters included cities and municipal settlements with an average mortality. The most favorable position has the Orenburg area with the lowest mortality rate in the region in 2017 - 8.4%. The dynamics of mortality rates among the male and female population tends to decrease, more pronounced dynamics is in men. Though, the male population is characterized by higher mortality rates in all age groups. The leading position among the causes of death is taken by diseases of the circulatory system (46.3% of the total mortality). The second position is occupied by tumors (17.2%), the third - by external causes (8.4%). Mortality from circulatory system diseases and from external causes has reduced. The dynamics of mortality from tumors does not change significantly. The rank of leading causes of death is not identical in the clusters: in the third and fourth clusters, the other causes occupy the second place in the structure of mortality, while tumors occupy the third. Conclusion. In the Orenburg region, the mortality rate is higher than overage in the Russian Federation by 0.9 per 1000 people. The study revealed significant territorial differences in the mortality rates. In general, the mortality among men in all age groups is higher than the mortality of women. The mortality rate from diseases of the circulatory system plays the leading role in the structure of mortality, but has the tendency for decline. Until 2006, the mortality from external causes ranked the second place, now the second place is taken by death from tumors The mortality from external causes is decreasing; mortality from tumors does not change significantly. The obtained results could be used by local authorities in developing the program of public health protection and assessing its effectiveness.

scholarly journals PENGARUH MUTILASI DAN ABLASI TERHADAP MOLTING KEPITING BAKAU (Scylla Serrata) SEBAGAI KEPITING LUNAK

2017 ◽  
Vol 2 (1) ◽  
pp. 81
Author(s):  
Khairiah Khairiah ◽  
Supriyono Eko Wardoyo ◽  
Pasril Wahid
Keyword(s):  
Mortality Rate ◽  
Scylla Serrata ◽  
Experimental Unit ◽  
Ablation Technique ◽  
The Third ◽  
Treatment Techniques ◽  
Mangrove Crab ◽  
Dark Color ◽  
And Control

Effect of Mutilation and Ablation to Molting of Mangrove Crab (Scylla serrata) as Soft Crab          Soft crabs that are more expensive than regular crab, that having hard carapace, in nature and in culture are very difficult to find. This study aimed to get the soft crabs more easily controlled the number  of molting in culture, by the method of mutilation and ablation. Thus the supply in market will be able to meet existing demand. Four treatment techniques had been implemented namely mutilation, ablation, ablation + mutilation, and controls which each performed four replications. Complete Randomized Desaign (CRD) was used because the experiment was conducted in a fairly homogeneous patch of tambak pond. Experimental unit in the form of bamboo pen cages with the size of 2x1x1m filled with 20 crabs.  All experimental crabs were ready for molting (dark color) even with 40-90 g of varied sizes. The results showed that each week until the third week, the average number of crabs per unit experiment with techniques of mutilation was always having highest of molting number, respectively 1.00, 3.25, and 11.00 crabs and having the lowest mortality rate, respectively  0. 25, 1.75, and 1.25 crabs, compared with the ablation, mutilations + ablation technique, and control. Statistically  four treatments in molting, in week two and  three was significantly different , eventhough in mortality was not (α = 5%).Keywords : mangrove crab (Scilla serrata), soft crabs, mutilation, ablation ABSTRAK                Kepiting lunak yang  harganya lebih mahal dari kepiting biasa bercangkang keras, di alam maupun dalam budidaya sangat susah ditemukan.  Penelitian ini bertujuan untuk mendapatkan kepiting lunak yang lebih mudah terkontrol jumlahnya dalam budidaya, dengan metoda mutilasi dan ablasi.  Dengan demikian dalam  pasar ketersediaannya akan dapat memenuhi permintaan yang ada. Empat perlakuan telah dilaksanakan yaitu teknik mutilasi, ablasi, mutilasi+ablasi, dan kontrol dengan masing-masing dilakukan empat kali ulangan. Rancangan Acak Lengkap (RAL) digunakan karena percobaan ini dilakukan di suatu petak tambak yang cukup homogen. Unit percobaan berupa keramba bambu tancap ukuran 2x1x1m yang diisi 20 kepiting yang semua kepiting dalam percobaan siap molting (warnanya gelap) meskipun dengan ukuran yang bervariatif 40-90 g. Hasil penelitian menunjukan bahwa tiap minggu sampai pada minggu ke tiga  rata-rata jumlah kepiting per unit percobaan dengan teknik mutilasi selalu tertinggi terjadinya proses molting yaitu masing–masing 1,00; 3,25; dan 11,00 ekor dan mortalitasnya terendah yaitu 0,25; 1,75; dan 1,25 ekor dibanding dengan teknik ablasi, mutilasi+ablasi; dan kontrol.  Secara statistik ke empat perlakuan dalam molting pada minggu ke dua dan ke tiga berbeda nyata hasil terbaik ditunjukkan oleh perlakuan mutilasi, meskipun dalam mortalitas tidak  berbeda nyata (selang kepercayaan 95 %).Kata Kunci : Kepiting bakau (Scilla serrata), kepiting lunak, mutilasi, ablasi.

scholarly journals Production of germ-free mosquitoes via transient colonisation allows stage-specific investigation of host-microbiota interactions

2019 ◽  
Author(s):  
Ottavia Romoli ◽  
Johan Claes Schönbeck ◽  
Siegfried Hapfelmeier ◽  
Mathilde Gendrin
Keyword(s):  
Larval Development ◽  
Emerging Adults ◽  
Larval Instar ◽  
Bacterial Colonisation ◽  
Germ Free ◽  
Functional Studies ◽  
The Third ◽  
Novel Approach ◽  
Folate Biosynthesis ◽  
Vector Borne

AbstractThe mosquito microbiota impacts the physiology of its host and is essential for normal larval development, thereby influencing transmission of vector-borne pathogens. Germ-free mosquitoes generated with current methods show larval stunting and developmental deficits. Therefore, functional studies of the mosquito microbiota have so far mostly been limited to antibiotic treatments of emerging adults. In this study, we developed a novel approach to produce germ-free Aedes aegypti mosquitoes. It is based on reversible colonisation with bacteria genetically modified to allow complete decolonisation at any developmental stage. We show that, unlike germ-free mosquitoes previously produced using sterile diets, reversibly colonised mosquitoes show no developmental retardation and reach the same size as control adults. This allowed us to uncouple the study of the microbiota in larvae and adults. In adults, we detected no impact of bacterial colonisation on mosquito fecundity or longevity. In larvae, we performed a transcriptome analysis and diet supplementation experiments following decolonisation during the third larval instar. Our data suggest that bacteria support larval development by contributing to folate biosynthesis and by enhancing energy storage. Our study establishes a novel tool to study the microbiota in insects and deepens our knowledge on the metabolic contribution of bacteria to mosquito development.

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