scholarly journals The type of blood used to feed Aedes aegypti females affects their cuticular and internal free fatty acid (FFA) profiles

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0251100
Author(s):  
Agata Kaczmarek ◽  
Anna Katarzyna Wrońska ◽  
Mieczysława Irena Boguś ◽  
Michalina Kazek ◽  
Aleksandra Gliniewicz ◽  
...  

Aedes aegypti, the primary vector of various arthropod-borne viral (arboviral) diseases such as dengue and Zika, is a popular laboratory model in vector biology. However, its maintenance in laboratory conditions is difficult, mostly because the females require blood meals to complete oogenesis, which is often provided as sheep blood. The outermost layer of the mosquito cuticle is consists of lipids which protects against numerous entomopathogens, prevents desiccation and plays an essential role in signalling processes. The aim of this work was to determine how the replacement of human blood with sheep blood affects the cuticular and internal FFA profiles of mosquitoes reared in laboratory culture. The individual FFAs present in cuticular and internal extracts from mosquito were identified and quantified by GC–MS method. The normality of their distribution was checked using the Kolmogorov-Smirnov test and the Student’s t-test was used to compare them. GC-MS analysis revealed similar numbers of internal and cuticular FFAs in the female mosquitoes fed sheep blood by membrane (MFSB) and naturally fed human blood (NFHB), however MFSB group demonstrated 3.1 times greater FFA concentrations in the cuticular fraction and 1.4 times the internal fraction than the NFHB group. In the MFSB group, FFA concentration was 1.6 times higher in the cuticular than the internal fraction, while for NFHB, FFA concentration was 1.3 times lower in the cuticular than the internal fraction. The concentration of C18:3 acid was 223 times higher in the internal fraction than the cuticle in the MHSB group but was absent in the NFHB group. MFSB mosquito demonstrate different FFA profiles to wild mosquitoes, which might influence their fertility and the results of vital processes studied under laboratory conditions. The membrane method of feeding mosquitoes is popular, but our research indicates significant differences in the FFA profiles of MFSB and NFHB. Such changes in FFA profile might influence female fertility, as well as other vital processes studied in laboratory conditions, such as the response to pesticides. Our work indicates that sheep blood has potential shortcomings as a substitute feed for human blood, as its use in laboratory studies may yield different results to those demonstrated by free-living mosquitoes.

2010 ◽  
Vol 100 (5) ◽  
pp. 599-603 ◽  
Author(s):  
D.D. Chadee

AbstractThe diel oviposition periodicity of two groups of Aedes aegypti females (Trinidad strain), (i) thoses allowed access to oviposition sites and (ii) females forced to retain-eggs for four days, were studied under laboratory conditions using one female per cage and monitoring by changing substrates every two hours. The individual females which were allowed access to oviposition sites showed peak oviposition between 16.00–18.00 h (50% of eggs), whereas individuals forced to retain eggs for four days showed a similar pattern but with a significantly (P<0.001) larger peak oviposition between 16.00–18.00 h (94% of eggs). However, females forced to retain eggs laid most or all of their eggs in one container (84%), while females given access to oviposition sites distributed their eggs among 2–4 containers. The results of this study are discussed in the context of the strength of the circadian rhythms, oviposition strategies and its impact on vector control activities.


2009 ◽  
Vol 24 ◽  
pp. 156 ◽  
Author(s):  
Ishan Gautam ◽  
Megh Nath Dhimal ◽  
Shambhu Raj Shrestha ◽  
Anand Shova Tamrakar

Aedes aegypti is the primary vector for the transmission of Dengue Fever (DF)/Dengue Haemorrhagic Fever (DHF). Entomological investigations on breeding habitats and larval prevalence of mosquitoes Aedes aegypti (L.) and Ae. albopictus (Skuse) were conducted from April to June 2009 in Kathmandu district, Nepal. Different water-filled containers were examined for the presence or absence of Aedes larvae. Larval survey techniques were used to obtain the House Index (HI), Container Index (CI) and Breteau Index (BI). The over all HI, CI and BI for Aedes aegypti were 6.25, 4.83, 9.37 and for Aedes albopictus were 6.25, 3.22 and 6.25 respectively. It was also observed that discarded tires lying outdoors were the preferred breeding habitats. No breeding was observed in other containers in April and May during this three months survey. Herewith, we report the first collection and identification of Aedes aegypti in Kathmandu during June, 2009. Indeed, this finding constitutes the first record from the capital of Nepal within the urban agglomeration of Basundhara and Gongabu-Balaju area.Therefore, DF/DHF transmission risk may occur locally if imported cases are introduced.  Key Words: Aedes aegypti; Ae. albopictus;  Kathmandu; First record; Dengue Fever.Journal of Natural History MuseumVol 24, 2009.Page:


2012 ◽  
pp. 74-84
Author(s):  
Thi Kieu Nhi Nguyen

Objectives: 1. Estimating the ratios of clinical and paraclinical signs of post-term newborns hospitalized at Pediatric Department of Hue University Hospital. 2. Identifying the relation between clinical signs and paraclinical signs. Materials and Method: 72 post- term babies < 7 days of life hospitalized at NICU from 2010/5 to 2011/4. Classification of post - term newborn was based on WHO 2003: gestational age ≥ 42 weeks with clinical manifestations: desquamation on press with fingers or natural desquamation, withered or meconial umbilicus, meconial long finger nails (*) or geatational age still < 42 weeks with theses clinical manifestations (*). Data were recorded on a clinical record form. Per-protocol analysis of clinical outcomes was performed by using Medcalc 11.5 and Excell 2007. Analyses used the χ2 test or Fisher's exact test for categorical data; Student's t test was used for continuous data and the Mann-Whitney U test for nonparametric data. Data were presented as means or proportions with 95% CIs. Results: Clinical characteristics: Tachypnea and grasp were main reasons of hospitalisation (48.61%). Poor feeding, vomitting (16.67%). Asphyxia (8.34%). Jawndice (6.94%). Hypothermia < 36.50C (13.89%), fever (13.89%). Tachypnea (59.72%). Bradycardia (1.39%). Poor feeding (11.11%). Hypertonia (9.72%). Paraclinical characteristics: Erythrocytes < 4.5.1012/l (51.39%), Leucocytes 5 – 25.103/mm3 (81.94%), Thrombocytes 100- 400.103/mm3 (94.44%). Hemoglobinemia < 10mg/l (67.61%). Maternal characteristics: Menstrual cycles regular (75%). Primiparity (75%). Amniotic volume average (70.42%), little (29.58%). Aminiotic liquid clair (62.5%), aminiotic liquid yellow (4.17%), aminiotic meconial liquid (33.33%). Maternal manifestation of one of many risk factors consist of genital infection; urinary infection; fever before, during, after 3 days of birth; prolonged delivery; medical diseases influence the foetus (75%). The relation between clinical signs and paraclinical signs: There was significantly statistical difference: between gestationnal age based on obstetrical criteria and amniotic volume on ultrasound (p < 0.05); between birth weight and glucosemia p < 0.02). There was conversional correlation of average level between erythroctes number and respiratory rate (r = - 0.5158; p < 0,0001), concordance correlation of weak level betwwen leucocytes number and respiratory rate r = 0.3045; p = 0.0093). Conclusion: It should made diagnosis of postterm baby based on degree of desquamation. The mother who has menstrual cycles regular is still delivered of a postterm baby. A postterm baby has the individual clinical and paraclinical signs.


Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 140 ◽  
Author(s):  
Véronique Paris ◽  
Ellen Cottingham ◽  
Perran Ross ◽  
Jason Axford ◽  
Ary Hoffmann

Wolbachia bacteria have been identified as a tool for reducing the transmission of arboviruses transmitted by Aedes aegypti. Research groups around the world are now mass rearing Wolbachia-infected Ae. aegypti for deliberate release. We investigated the fitness impact of a crucial element of mass rearing: the blood meal required by female Ae. aegypti to lay eggs. Although Ae. aegypti almost exclusively feed on human blood, it is often difficult to use human blood in disease-endemic settings. When females were fed on sheep or pig blood rather than human blood, egg hatch rates decreased in all three lines tested (uninfected, or infected by wMel, or wAlbB Wolbachia). This finding was particularly pronounced when fed on sheep blood, although fecundity was not affected. Some of these effects persisted after an additional generation on human blood. Attempts to keep populations on sheep and pig blood sources only partly succeeded, suggesting that strong adaptation is required to develop a stably infected line on an alternative blood source. There was a decrease in Wolbachia density when Ae. aegypti were fed on non-human blood sources. Density increased in lines kept for multiple generations on the alternate sources but was still reduced relative to lines kept on human blood. These findings suggest that sheep and pig blood will entail a cost when used for maintaining Wolbachia-infected Ae. aegypti. These costs should be taken into account when planning mass release programs.


2018 ◽  
Vol 10 (10) ◽  
pp. 1601 ◽  
Author(s):  
Carl Talsma ◽  
Stephen Good ◽  
Diego Miralles ◽  
Joshua Fisher ◽  
Brecht Martens ◽  
...  

Accurately estimating evapotranspiration (ET) at large spatial scales is essential to our understanding of land-atmosphere coupling and the surface balance of water and energy. Comparisons between remote sensing-based ET models are difficult due to diversity in model formulation, parametrization and data requirements. The constituent components of ET have been shown to deviate substantially among models as well as between models and field estimates. This study analyses the sensitivity of three global ET remote sensing models in an attempt to isolate the error associated with forcing uncertainty and reveal the underlying variables driving the model components. We examine the transpiration, soil evaporation, interception and total ET estimates of the Penman-Monteith model from the Moderate Resolution Imaging Spectroradiometer (PM-MOD), the Priestley-Taylor Jet Propulsion Laboratory model (PT-JPL) and the Global Land Evaporation Amsterdam Model (GLEAM) at 42 sites where ET components have been measured using field techniques. We analyse the sensitivity of the models based on the uncertainty of the input variables and as a function of the raw value of the variables themselves. We find that, at 10% added uncertainty levels, the total ET estimates from PT-JPL, PM-MOD and GLEAM are most sensitive to Normalized Difference Vegetation Index (NDVI) (%RMSD = 100.0), relative humidity (%RMSD = 122.3) and net radiation (%RMSD = 7.49), respectively. Consistently, systemic bias introduced by forcing uncertainty in the component estimates is mitigated when components are aggregated to a total ET estimate. These results suggest that slight changes to forcing may result in outsized variation in ET partitioning and relatively smaller changes to the total ET estimates. Our results help to explain why model estimates of total ET perform relatively well despite large inter-model divergence in the individual ET component estimates.


2019 ◽  
Vol 8 (1) ◽  
pp. 1-7
Author(s):  
Dora Dayu Rahma Turista ◽  
Eka Puspitasari

BAP media is a medium used to distinguish pathogenic bacteria based on their hemolytic power on red blood cells. Staphyllococcus aureus is a bacterium that is able to emolate red blood cells with 3 types of hemolysis, namely α, β, γ, and δ. Usually BAP media is made by adding 5-10% sheep blood. Making BAP media using sheep blood has become a problem for several laboratories today, including health education laboratories. This is because the health education laboratory does not yet have a sheep farm, so it has not been able to procure sheep blood. The use of human blood as a substitute for sheep blood in making BAP media may be a solution, but it is not yet known whether there are differences in the growth and hemolysis of S. aureus bacteria on BAP media in sheep's blood and human blood. This research is an experimental study with a completely randomized design (CRD) of 3 replications which aims to determine whether there are differences in growth and hemolysis of bacteria S. aureus in BAP media of sheep blood and human blood groups A, B, AB, and O. The results showed that S. aureus bacteria could grow and show hemolysis in BAP media in sheep blood and human blood in groups A, B, AB, and O. The results of subsequent studies analyzed ANOVA using the software spss for windows with a significant level of 0.05. From the results of research and data analysis it can be concluded that S. aureus bacteria can grow and show hemolysis in BAP media of sheep blood and human blood groups A, B, AB and O, but there are significant differences in the number of S. aureus bacteria colonies grown in BAP media of sheep's blood and human blood groups A, B, AB and O.


2015 ◽  
Vol 05 (07) ◽  
pp. 299-305 ◽  
Author(s):  
Ahmed M. Alshammari ◽  
Abdullah S. Alshammari ◽  
Adel A. Abdelmageed ◽  
Ashraf A. Mangoud ◽  
Naimah A. Al Anazi ◽  
...  

1956 ◽  
Vol 9 (1) ◽  
pp. 125 ◽  
Author(s):  
AK O’gower

The rate of ciigesl;iol1 of human blood was invcsLigated at 4-hourly intorval" by tho I'reeipitin and benzidine tests for tho mosquito species .Aedes aegypti, A. concolor, A. noto8oriptu8, A. soutellaris, and Culea., fllliymis. In an enviroWllent ill which temperature and humidity w('["o oonstant and in whioh thoro were equal periods of light and darkness, the mie of digestion ranged from :11 hI' for 8CUtellm'is to ·Hl hI' for A. COil color.


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