The Effect of Temperature on Development and Diapause of the Horn Fly, Siphona irritans (L.) (Diptera: Muscidae)

1961 ◽  
Vol 93 (10) ◽  
pp. 855-859 ◽  
Author(s):  
K. R. Depner
Keyword(s):  
Effect Of Temperature ◽  
Host Animal ◽  
Horn Fly ◽  
Laboratory Colony ◽  
Southern Alberta ◽  
Single Host

Siphona irritans (L.), commonly known as the horn fly, is a serious pest of cattle. In southern Alberta, ten thousand flies have been counted on a single host animal. Properly conducted control studies require the establishment of a permanent laboratory colony. Previous attempts to establish such a colony had not been successful (McLintock and Depner, 1957) as more information about the biology of the fly was needed. The results presented in this paper will help provide this information.

scholarly journals Blood Meal Sources of Anopheles spp. in Malaria Endemic Areas of Honduras

Insects ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 450
Author(s):  
Denis Escobar ◽  
Krisnaya Ascencio ◽  
Andrés Ortiz ◽  
Adalid Palma ◽  
Ana Sánchez ◽  
...  
Keyword(s):  
Blood Meal ◽  
Host Animal ◽  
Specific Primers ◽  
Anopheles Mosquitoes ◽  
Single Host ◽  
Life Threatening ◽  
Animal Hosts ◽  
Endemic Areas ◽  
Species Specific ◽  
Feeding Sources

Malaria remains a life-threatening disease in many tropical countries. Honduras has successfully reduced malaria transmission as different control methods have been applied, focusing mainly on indoor mosquitoes. The selective pressure exerted by the use of insecticides inside the households could modify the feeding behavior of the mosquitoes, forcing them to search for available animal hosts outside the houses. These animal hosts in the peridomicile could consequently become an important factor in maintaining vector populations in endemic areas. Herein, we investigated the blood meal sources and Plasmodium spp. infection on anophelines collected outdoors in endemic areas of Honduras. Individual PCR reactions with species-specific primers were used to detect five feeding sources on 181 visibly engorged mosquitoes. In addition, a subset of these mosquitoes was chosen for pathogen analysis by a nested PCR approach. Most mosquitoes fed on multiple hosts (2 to 4), and 24.9% of mosquitoes had fed on a single host, animal or human. Chicken and bovine were the most frequent blood meal sources (29.5% and 27.5%, respectively). The average human blood index (HBI) was 22.1%. None of the mosquitoes were found to be infected with Plasmodium spp. Our results show the opportunistic and zoophilic behavior of Anopheles mosquitoes in Honduras.

scholarly journals Genetic Characterization of Escherichia coli Populations from Host Sources of Fecal Pollution by Using DNA Fingerprinting

2003 ◽  
Vol 69 (5) ◽  
pp. 2587-2594 ◽  
Author(s):  
Sandra L. McLellan ◽  
Annette D. Daniels ◽  
Alissa K. Salmore
Keyword(s):  
Escherichia Coli ◽  
Pairwise Comparison ◽  
Fecal Pollution ◽  
Host Animal ◽  
Host Group ◽  
E Coli ◽  
Single Host ◽  
Relationship Of ◽  
The Relationship

ABSTRACT Escherichia coli isolates were obtained from common host sources of fecal pollution and characterized by using repetitive extragenic palindromic (REP) PCR fingerprinting. The genetic relationship of strains within each host group was assessed as was the relationship of strains among different host groups. Multiple isolates from a single host animal (gull, human, or dog) were found to be identical; however, in some of the animals, additional strains occurred at a lower frequency. REP PCR fingerprint patterns of isolates from sewage (n = 180), gulls (n = 133), and dairy cattle (n = 121) were diverse; within a host group, pairwise comparison similarity indices ranged from 98% to as low as 15%. A composite dendrogram of E. coli fingerprint patterns did not cluster the isolates into distinct host groups but rather produced numerous subclusters (approximately >80% similarity scores calculated with the cosine coefficient) that were nearly exclusive for a host group. Approximately 65% of the isolates analyzed were arranged into host-specific groups. Comparable results were obtained by using enterobacterial repetitive intergenic consensus PCR and pulsed-field gel electrophoresis (PFGE), where PFGE gave a higher differentiation of closely related strains than both PCR techniques. These results demonstrate that environmental studies with genetic comparisons to detect sources of E. coli contamination will require extensive isolation of strains to encompass E. coli strain diversity found in host sources of contamination. These findings will assist in the development of approaches to determine sources of fecal pollution, an effort important for protecting water resources and public health.

Effect of temperature onWolbachiadensity and impact on cytoplasmic incompatibility

Parasitology ◽  
2005 ◽  
Vol 132 (1) ◽  
pp. 49-56 ◽  
Author(s):  
L. MOUTON ◽  
H. HENRI ◽  
M. BOULETREAU ◽  
F. VAVRE
Keyword(s):  
Cytoplasmic Incompatibility ◽  
Environmental Changes ◽  
Complex Interaction ◽  
Effect Of Temperature ◽  
Environmental Constraints ◽  
Temperature Changes ◽  
Real Time Quantitative Pcr ◽  
Single Host ◽  
Host Development ◽  
Single Insect

The outcome and the evolution of host-symbiont associations depend on environmental constraints, but responses are difficult to predict since they arise from a complex interaction between the host, the parasite and the environment. The situation can be even more complex when multiple parasite genotypes, with potentially different responses to environmental changes, coexist within a single host. In this paper, we investigated the effect of the temperature (from 14 to 26 °C) during the host development on the density of 3 strains of the intracellular bacteriumWolbachiathat coexist within the waspLeptopilina heterotoma. In this species,Wolbachiainduces cytoplasmic incompatibility, a sperm-egg incompatibility that allows it to spread and persist in host populations. Using real-time quantitative PCR we found that (i)Wolbachiadensity is temperature-specific and highest at 26 °C; (ii) the order of the abundance of the 3Wolbachiastrains does not vary with temperature changes; (iii) the response of bacterial density to temperature occurs within a single insect generation, during the egg-to-adult developmental period; (iv) in this species, temperature-related changes inWolbachiadensity do not influence cytoplasmic incompatibility.

EFFECT OF TEMPORAL FACTORS ON REPRODUCTIVE ISOLATION BETWEEN CHORISTONEURA OCCIDENTALIS AND C. RETINIANA (LEPIDOPTERA: TORTRICIDAE)

1984 ◽  
Vol 116 (7) ◽  
pp. 991-1005 ◽  
Author(s):  
Andrew M. Liebhold ◽  
W. Jan A. Volney
Keyword(s):  
Circadian Rhythm ◽  
Reproductive Isolation ◽  
Effect Of Temperature ◽  
Choristoneura Occidentalis ◽  
Laboratory Studies ◽  
Male Attraction ◽  
South Central ◽  
Baited Traps ◽  
Laboratory Colony ◽  
Temporal Factors

AbstractThe seasonal distributions of Choristoneura occidentalis Freeman and C. retiniana (Walsingham) males attracted to pheromone sources overlapped considerably at two sites in south-central Oregon. Bimodality in the seasonal distributions of trapped males of both species was associated with a period of cool weather. The daily periods of female calling, and attraction of males to female-baited traps and to chemically baited traps overlapped greatly between the two species. However, these three aspects of C. occidentalis mating behavior began 1–2 h before those of C. retiniana. Under laboratory conditions, there was also considerable overlap in the calling periods of the two species; but again, C. occidentalis females initiated calling slightly earlier than did female C. retiniana. Females of both species continued to call many hours past the cessation of male attraction to pheromones in the field. Male attraction to pheromones occurred earlier on cool evenings than on warm evenings. Laboratory studies indicated a similar effect of temperature on timing of female calling. Little intraspecific variation in calling periodicity was observed among field-collected populations of each species. However, a C. occidentalis laboratory colony appeared to have partially lost its circadian rhythm of calling.

scholarly journals Blood Meal Sources of Anopheles spp. in Malaria Endemic Areas of Honduras

2020 ◽  
Author(s):  
Denis Escobar ◽  
Krisnaya Ascencio ◽  
Andrés Ortiz ◽  
Adalid Palma ◽  
Ana Sánchez ◽  
...  
Keyword(s):  
Blood Meal ◽  
Host Animal ◽  
Specific Primers ◽  
Anopheles Mosquitoes ◽  
Single Host ◽  
Life Threatening ◽  
Animal Hosts ◽  
Endemic Areas ◽  
Species Specific ◽  
Feeding Sources

Malaria remains a life-threatening disease in many tropical countries. Honduras has successfully reduced malaria transmission as different control methods have been applied focusing mainly on indoor mosquitoes. The selective pressure exerted by the use of insecticides inside the households could modify the feeding behavior of the mosquitoes forcing them to search for available animal hosts outside the houses. These animal hosts in the peridomicile could consequently become an important factor in maintaining vector populations in endemic areas. Herein, we investigated the blood meal sources and Plasmodium spp. infection on anophelines collected outdoors in endemic areas of Honduras. Individual PCR reactions with species-specific primers were used to detect five feeding sources on 181 visibly engorged mosquitoes. In addition, a subset of these mosquitoes where chosen for pathogen analysis by a nested PCR approach. Most mosquitoes fed on multiple hosts (2 to 4), and 24.9% of mosquitoes were fed on a single host, animal or human. Chicken and bovine were the most frequent blood meal sources (29.5% and 27.5% respectively). The average human blood index (HBI) was 22.1%. None of the mosquitoes was found to be infected with Plasmodium spp. Our results show the opportunistic and zoophilic behavior of Anopheles mosquitoes in Honduras.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

The effect of temperature on high-resolution TEM image contrast

1995 ◽  
Vol 53 ◽  
pp. 640-641
Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz
Keyword(s):  
Form Factor ◽  
Inelastic Scattering ◽  
Accurate Method ◽  
Waller Factor ◽  
Effect Of Temperature ◽  
Specimen Thickness ◽  
Influence Of Temperature ◽  
Debye Waller Factor ◽  
Influence Of Temperature On ◽  
Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

A scanning electron microscopic study of the eggs of Culicoides variipennis (Diptera: Ceratopogonidae)

1987 ◽  
Vol 45 ◽  
pp. 884-885 ◽  
Author(s):  
R. A. Nunamaker ◽  
C. E. Nunamaker ◽  
B. C. Wick
Keyword(s):  
Distinct Species ◽  
Hemorrhagic Disease ◽  
Insect Vector ◽  
Electron Microscopic ◽  
Important Species ◽  
Scanning Electron Microscopic Study ◽  
Laboratory Colony ◽  
Culicoides Variipennis ◽  
Morphological Differences ◽  
Scanning Electron

Culicoides variipennis (Coquillett) is probably the most economically important species of biting midge in the U.S. due to its involvement in the transmission of bluetongue (BT) disease of sheep, cattle and ruminant wildlife, and epizootic hemorrhagic disease (EHD) of deer. Proposals have been made to recognize the eastern and western populations of this insect vector as distinct species. Others recommend use of the term “variipennis complex” until such time that the necessary biosystematic studies have been made to determine the genetic nature and/or minute morphological differences within the population structure over the entire geographic range of the species. Increasingly, students of ootaxonomy are relying on scanning electron microscopy (SEM) to assess chorionic features. This study was undertaken to provide comparative chorionic data for the C. variipennis complex.Culicoides variipennis eggs were collected from a laboratory colony maintained in Laramie, Wyoming.

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