scholarly journals Fitness characteristics of the malaria vector Anopheles funestus during an attempted laboratory colonization

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Halfan S. Ngowo ◽  
Emmanuel E. Hape ◽  
Jason Matthiopoulos ◽  
Heather M. Ferguson ◽  
Fredros O. Okumu
Keyword(s):  
Malaria Vector ◽  
Mating Success ◽  
Wing Length ◽  
Anopheles Funestus ◽  
Larval Survival ◽  
Future Studies ◽  
Laboratory Conditions ◽  
Median Lifespan ◽  
And Control ◽  
Success Percentage

Abstract Background The malaria vector Anopheles funestus is increasingly recognized as a dominant vector of residual transmission in many African settings. Efforts to better understand its biology and control are significantly impeded by the difficulties of colonizing it under laboratory conditions. To identify key bottlenecks in colonization, this study compared the development and fitness characteristics of wild An. funestus from Tanzania (FUTAZ) and their F1 offspring during colonization attempts. The demography and reproductive success of wild FUTAZ offspring were compared to that of individuals from one of the only An. funestus strains that has been successfully colonized (FUMOZ, from Mozambique) under similar laboratory conditions. Methods Wild An. funestus (FUTAZ) were collected from three Tanzanian villages and maintained inside an insectary at 70–85% RH, 25–27 °C and 12 h:12 h photoperiod. Eggs from these females were used to establish three replicate F1 laboratory generations. Larval development, survival, fecundity, mating success, percentage pupation and wing length were measured in the F1 -FUTAZ offspring and compared with wild FUTAZ and FUMOZ mosquitoes. Results Wild FUTAZ laid fewer eggs (64.1; 95% CI [63.2, 65.0]) than FUMOZ females (76.1; 95% CI [73.3, 79.1]). Survival of F1-FUTAZ larvae under laboratory conditions was low, with an egg-to-pupae conversion rate of only 5.9% compared to 27.4% in FUMOZ. The median lifespan of F1-FUTAZ females (32 days) and males (33 days) was lower than FUMOZ (52 and 49 for females and males respectively). The proportion of female F1-FUTAZ inseminated under laboratory conditions (9%) was considerably lower than either FUMOZ (72%) or wild-caught FUTAZ females (92%). This resulted in nearly zero viable F2-FUTAZ eggs produced. Wild FUTAZ wings appear to be larger compared to the lab reared F1-FUTAZ and FUMOZ. Conclusions This study indicates that poor larval survival, mating success, low fecundity and shorter survival under laboratory conditions all contribute to difficulties in colonizing of An. funestus. Future studies should focus on enhancing these aspects of An. funestus fitness in the laboratory, with the biggest barrier likely to be poor mating.

scholarly journals Fitness Characteristics of the Malaria Vector, Anopheles Funestus, During an Attempted Laboratory Colonization

2020 ◽  
Author(s):  
Halfan S Ngowo ◽  
Emmanuel E Hape ◽  
Jason Matthiopoulos ◽  
Heather M Ferguson ◽  
Fredros O Okumu
Keyword(s):  
Malaria Vector ◽  
Mating Success ◽  
Wing Length ◽  
Anopheles Funestus ◽  
Larval Survival ◽  
Future Studies ◽  
Laboratory Conditions ◽  
Median Lifespan ◽  
And Control ◽  
Success Percentage

Abstract Introduction: The malaria vector Anopheles funestus is increasingly recognized as a dominant vector of residual transmission in many African settings. Efforts to better understand its biology and control are significantly impeded by the difficulties of colonizing it under laboratory conditions. To identify key bottlenecks in colonization, this study compared the development and fitness characteristics of wild An. funestus from Tanzania (FUTAZ) and their F1 offspring during colonization attempts. The demography and reproductive success of wild FUTAZ offspring were compared to that of individuals from one of the only An. funestus strains that has been successfully colonized (FUMOZ, from Mozambique) under similar laboratory conditions.Methods: Wild An. funestus (FUTAZ) were collected from three Tanzanian villages and maintained inside an insectary at 70-85% RH, 25-27oC and 12hr:12hr photoperiod. Eggs from these females were used to establish three replicate F1 laboratory generations. Larval development, survival, fecundity, mating success, percentage pupation and wing length were measured in the F1 FUTAZ offspring and compared with wild FUTAZ and FUMOZ mosquitoes.Results: Wild FUTAZ laid fewer eggs (64.1; 95%CI [63.2, 65.0]) than FUMOZ females (76.1; 95%CI [73.3, 79.1]). Survival of F1-FUTAZ larvae under laboratory conditions was low, with an egg-to-pupae conversion rate of only 5.9% compared to 27.4% in FUMOZ. The median lifespan of F1-FUTAZ females (32 days) and males (33 days) was lower than FUMOZ (52 and 49 for females and males respectively). The proportion of female F1-FUTAZ inseminated under laboratory conditions (9%) was considerably lower than either FUMOZ (72%) or wild-caught FUTAZ females (92%). This resulted in nearly zero viable F2-FUTAZ eggs produced. Wild FUTAZ wings appear to be larger compared to the lab reared F1-FUTAZ and FUMOZ. Conclusions: This study indicates that poor larval survival, mating success, low adult fecundity and shorter survival under laboratory conditions all contribute to difficulties in colonizing of An. funestus. Future studies should focus on enhancing these aspects of An. funestus fitness in the laboratory, with the biggest barrier likely to be poor mating.

scholarly journals Evidence of a multiple insecticide resistance in the malaria vector Anopheles funestus in South West Nigeria

2016 ◽  
Vol 15 (1) ◽  
Author(s):  
Rousseau J. Djouaka ◽  
Seun M. Atoyebi ◽  
Genevieve M. Tchigossou ◽  
Jacob M. Riveron ◽  
Helen Irving ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Malaria Vector ◽  
Anopheles Funestus ◽  
South West

scholarly journals Attraction of Astylus variegatus (Germ.) (Coleoptera: Melyridae) by volatile floral attractants

2007 ◽  
Vol 64 (3) ◽  
pp. 305-307 ◽  
Author(s):  
Maurício Ursi Ventura ◽  
Tania Pereira ◽  
Daiane Heloisa Nunes ◽  
Iara Cintra de Arruda
Keyword(s):  
Phaseolus Vulgaris ◽  
Common Beans ◽  
Phaseolus Vulgaris L ◽  
Release Rates ◽  
Plastic Strip ◽  
Feeding Stimulant ◽  
Laboratory Conditions ◽  
Diabrotica Speciosa ◽  
And Control ◽  
Lagenaria Vulgaris

The beetle Astylus variegatus (Germ.) (Coleoptera: Melyridae) is frequently found in flowers feeding on pollen. Responses of A. variegatus to volatile floral attractants were studied in common beans (Phaseolus vulgaris L.) fields. Traps originally designed to capture Diabrotica speciosa (Germ.) (Coleoptera: Chrysomelidae), consisted of plastic bottles (2 L) with 150 holes (5-mm diameter) yellow gold painted and containing inside a plastic strip (3.5 <FONT FACE=Symbol>´</FONT> 25 cm) with Lagenaria vulgaris (L.) powder (0.28% B cucurbitacin - feeding stimulant and arrestant for diabroticites) sprayed with carbaril insecticide. Treatments consisted of 1,4-dimethoxybenzene (one or two dispensers per trap), 1,4-dimethoxybenze + indole, 1,4-dimethoxybenzene + cinnameldehyde and control. Volatile average release rates (over ten days) was approximately 32 mg day-1 per dispenser under laboratory conditions. 1,4-dimethoxybenzene-lured traps caught significantly more beetles than the control, three and seven days after trap setting. Ten days after the onset of the experiment, there were no differences in number of beetles caught by treatments. Captures were higher in the 1,4-dimethoxybenzene + cinnamaldehyde treatment than in 1,4-dimethoxybenzene only in the first assessment. Adding indole to 1,4-dimethoxybenzene did not improve beetle captures.

Theory A, Theory B and Theory C of managing people at work

2021 ◽  
Vol 5 (1) ◽  
pp. 69-75
Author(s):  
Birendra Nath Singh
Keyword(s):  
Empirical Studies ◽  
Shop Floor ◽  
Scientific Management ◽  
Business Organization ◽  
Business Organizations ◽  
Research Gaps ◽  
Future Studies ◽  
Modern Business ◽  
And Control ◽  
The Impact

Managing people and productivity are prime concerns of modern business organizations. Many empirical studies were conducted during the era of scientific management (Taylor, 1911) to investigate What and How? McGregor’s (1960) epic theory — Theory X and Theory Y, categorizing all employees into two groups and prescribing methods to motivate and control them was the best. However, his findings also suffered strong criticisms, creating research gaps. The objective of this study was to investigate further and to conclude that there are three major groups named Theory A, Theory B, and Theory C. Amongst them, a middle group — Theory B is most dominant, having all capabilities to significantly influence productivity and prosperity of organizations. The methodology used was qualitative, based upon intensive and critical shop-floor observations. Since this study was not empirical, it had many limitations requiring further researches. Therefore, rightly recommended that future studies should correlate the impact of technological advancements upon motivations and productivity of the modern business organization (Veitch, 2018).

scholarly journals A chromosome-scale assembly of the major African malaria vector Anopheles funestus

GigaScience ◽  
2019 ◽  
Vol 8 (6) ◽  
Author(s):  
Jay Ghurye ◽  
Sergey Koren ◽  
Scott T Small ◽  
Seth Redmond ◽  
Paul Howell ◽  
...  
Keyword(s):  
Malaria Vector ◽  
Anopheles Funestus

scholarly journals Exposure to the insecticide-treated bednet PermaNet 2.0 reduces the longevity of the wild African malaria vector Anopheles funestus but GSTe2-resistant mosquitoes live longer

PLoS ONE ◽  
2019 ◽  
Vol 14 (3) ◽  
pp. e0213949 ◽  
Author(s):  
Ange Tchakounte ◽  
Magellan Tchouakui ◽  
Chiang Mu-Chun ◽  
Williams Tchapga ◽  
Edmond Kopia ◽  
...  
Keyword(s):  
Malaria Vector ◽  
Anopheles Funestus

Current status of Plasmodium knowlesi vectors: a public health concern?

Parasitology ◽  
2016 ◽  
Vol 145 (1) ◽  
pp. 32-40 ◽  
Author(s):  
I. VYTHILINGAM ◽  
M. L. WONG ◽  
W. S. WAN-YUSSOF
Keyword(s):  
Public Health ◽  
Plasmodium Knowlesi ◽  
Point Of View ◽  
Control Measures ◽  
Health Concern ◽  
Current Status ◽  
Malaria Vectors ◽  
Future Studies ◽  
Simian Malaria ◽  
And Control

SUMMARYPlasmodium knowlesi a simian malaria parasite is currently affecting humans in Southeast Asia. Malaysia has reported the most number of cases and P. knowlesi is the predominant species occurring in humans. The vectors of P. knowlesi belong to the Leucosphyrus group of Anopheles mosquitoes. These are generally described as forest-dwelling mosquitoes. With deforestation and changes in land-use, some species have become predominant in farms and villages. However, knowledge on the distribution of these vectors in the country is sparse. From a public health point of view it is important to know the vectors, so that risk factors towards knowlesi malaria can be identified and control measures instituted where possible. Here, we review what is known about the knowlesi malaria vectors and ascertain the gaps in knowledge, so that future studies could concentrate on this paucity of data in-order to address this zoonotic problem.

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