Paramphistomum daubneyi and Fasciola hepatica : influence of temperature changes on the shedding of cercariae from dually infected Lymnaea truncatula

1999 ◽  
Vol 85 (8-9) ◽  
pp. 765-769 ◽  
Author(s):  
M. Abrous ◽  
D. Rondelaud ◽  
G. Dreyfuss
Keyword(s):  
Fasciola Hepatica ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Lymnaea Truncatula

The Influence of Temperature on the Infectivity of Fasciola hepatica Miracidia to Lymnaea truncatula

1976 ◽  
Vol 62 (5) ◽  
pp. 698 ◽  
Author(s):  
Niels Ornbjerg Christensen ◽  
Peter Nansen ◽  
Flemming Frandsen
Keyword(s):  
Fasciola Hepatica ◽  
Influence Of Temperature ◽  
Lymnaea Truncatula ◽  
Influence Of Temperature On

Flow Behaviors of High Acyl Gellan Aqueous Solutions as Affected by Temperature, and Calcium and Gellan Concentrations

2008 ◽  
Vol 4 (5) ◽  
Author(s):  
Yiqun Huang ◽  
Pawan Singh Takhar ◽  
Juming Tang ◽  
Barry G Swanson
Keyword(s):  
Shear Rate ◽  
Aqueous Solutions ◽  
Apparent Viscosity ◽  
Flow Resistance ◽  
Effect Of Temperature ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Rheological Behaviors ◽  
Low Concentrations ◽  
Influence Of Temperature On

Rheological behaviors of high acyl (HA) gellan are not well understood partially because of its relatively late commercialization compared to low acyl gellan. The objective of this study was to investigate the effect of temperature (5-30 °C), calcium (0, 1 and 10 mM) and gellan concentrations (0.0044-0.1000% w/v) on the flow behaviors of high acyl gellan aqueous solutions using rheological tests. Gellan solutions with 0 or 1 mM added Ca++ exhibited shear thinning behavior at gellan concentrations above 0.0125%. The influence of temperature on apparent viscosity (shear rate, 100 s-1) of gellan solutions can be described with an Arrhenius relationship. The apparent viscosity of gellan solution at low concentrations was more sensitive to temperature changes. The addition of Ca++ led to a decrease in flow resistance for a dilute gellan solution (<0.0125%), but an increased resistance for a relatively concentrated gellan solution (>0.0125%).

The effects of Fasciola hepatica on Lymnaea truncatula

Parasitology ◽  
1972 ◽  
Vol 65 (2) ◽  
pp. 359-369 ◽  
Author(s):  
J. K. M. Hodasi
Keyword(s):  
Rapid Growth ◽  
Egg Production ◽  
Fasciola Hepatica ◽  
Age Groups ◽  
Sharp Decline ◽  
General Belief ◽  
Functional Changes ◽  
Complete Cessation ◽  
Lymnaea Truncatula ◽  
Accelerated Growth

Among the functional changes observed in L. truncatula infected with F. hepatica were those of growth, reproduction and mortality. For the first 3 weeks after infection there was no difference between the growth of infected and uninfected groups of snails. Thereafter there was a temporary accelerated growth which occurred between the fourth and seventh weeks after infection. The onset of this period of rapid growth in the different age groups of infected snails coincided with the time of migration of the rediae into the hepatopancreas. Of more significance was the influence of infection on the reproduction of the snail. There was a sharp decline in oviposition 2–3 weeks after infection, followed by a complete cessation of egg production at the end of the fifth week. Once oviposition ceased, it was not resumed and there was no self-cure. Contrary to general belief, infected groups of L. truncatula have been found to live longer than the uninfected controls. With isolated snails, however, there was a tendency for the uninfected snails to live longer than the infected ones. The possible interpretation of the discrepancies between isolated and mass cultured snails are discussed. The hepatopancreas and the gonad (ovotestis) were the two structures directly affected by the infection. Establishment of the rediae in the hepatopancreas invariably resulted in parasitic castration.

scholarly journals Natural infection of Lymnaea truncatula by the liver fluke Fasciola hepatica in the Porma Basin, León, NW Spain

1991 ◽  
Vol 65 (1) ◽  
pp. 15-27 ◽  
Author(s):  
Y. Manga-Gonzalez ◽  
C. Gonzalez-Lanza ◽  
C. B. Otero-Merino
Keyword(s):  
Liver Fluke ◽  
Fasciola Hepatica ◽  
Natural Infection ◽  
Infection Prevalence ◽  
Average Intensity ◽  
Nw Spain ◽  
Chi Square ◽  
Monthly Average ◽  
Lymnaea Truncatula ◽  
Chi Square Test

ABSTRACTFor two years fortnightly malacological samplings were carried out to collect Lymnaea truncatula (Mollusca; Basommatophora) at five points in the upper and middle Porma river basin, León, Spain. The highest numbers of snails were collected in September, May and November. Of the 5486 molluscs examined, 11·41% harboured F. hepatica (Trematoda; Digenea) with an average intensity of 20·14. In general, the values of both infection prevalence and intensity increased with the size of the snails. It was in October when the highest figures for each parameter mentioned above were detected (18·73% and 28·48, respectively). The chi-square test showed statistically significant differences in relation to the infection prevalence among the groups of molluscs established according to: their length; the months in which they were collected; the sampling localities; monthly average ambient temperature; precipitation during the collection. Similarly, statistically significant differences were detected in the intensity of the infection among the groups of molluscs previously established, except for that based on the values of precipitation. Generally, parasites were found in the same snail at different stages of development. It seems that most mollusc infections occur in February–March and at the end of summer–beginning of autumn periods. The highest rate of rediae with mature cercariae ready to be shed were detected between September and December. Metacercariae in the grass samples were also observed at the end of autumn. For this reason, this period could be considered as the most suitable for infection of the definitive hosts to take place.

Potential influence of temperature changes in the Southern Hemisphere on the evolution of the Asian summer monsoon during the last glacial period

2016 ◽  
Vol 392 ◽  
pp. 239-250 ◽  
Author(s):  
Li-Yin Han ◽  
Ting-Yong Li ◽  
Hai Cheng ◽  
R. Lawrence Edwards ◽  
Chuan-Chou Shen ◽  
...  
Keyword(s):  
Southern Hemisphere ◽  
Summer Monsoon ◽  
Asian Summer Monsoon ◽  
Glacial Period ◽  
Potential Influence ◽  
Last Glacial Period ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Asian Summer ◽  
The Last Glacial

Cercarial productivity of redial generations in single-miracidium infections of Lymnaea truncatula with Paramphistomum daubneyi or Fasciola hepatica

2000 ◽  
Vol 74 (1) ◽  
pp. 1-5 ◽  
Author(s):  
M. Abrous ◽  
D. Rondelaud ◽  
G. Dreyfuss
Keyword(s):  
Fasciola Hepatica ◽  
The Other ◽  
Redial Generation ◽  
Post Exposure ◽  
Laboratory Conditions ◽  
Lymnaea Truncatula

AbstractSingle-miracidium infections of Lymnaea truncatula with Paramphistomum daubneyi or with Fasciola hepatica were carried out under laboratory conditions to count free rediae, their germinal embryos, and to determine the cercarial productivity of each redial generation. In snails infected by P. daubneyi, the cercariae were produced by the first (8.7 cercariae per redia) and second (8.9 per redia) generations. At day 63 post-exposure, they corresponded, respectively, to 53.9% and 46.1% of cercariae produced by all rediae. In snails infected by F. hepatica, the majority of cercariae were produced by the R2a group (18.2 cercariae per redia) and corresponded to 66.0% of cercariae produced all rediae. The cercariae produced by the other redial groups were more limited in number: 17.5 per redia in the R1b group (28.7%) and 2.0 per redia in the R2b/R3a group (5.3%). Cercarial productivity of P. daubneyi until day 63 post-exposure was more limited in number than that of F. hepatica: a total of 145 cercariae per snail versus 427 per snail.

scholarly journals Influence of temperature gradient on surface texture measurements with the use of profilometry

2017 ◽  
Vol 65 (1) ◽  
pp. 53-62 ◽  
Author(s):  
T. Miller ◽  
S. Adamczak ◽  
J. Świderski ◽  
M. Wieczorowski ◽  
A. Łętocha ◽  
...  
Keyword(s):  
Temperature Gradient ◽  
Ambient Temperature ◽  
Surface Texture ◽  
Air Conditioning ◽  
Temperature Variations ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Simultaneous Registration ◽  
Probe Measurements ◽  
Conditioning Control

Abstract The paper presents an analysis of influence of ambient temperature changes on the values of parameters in topography measurements with the use of different profilometry techniques. In order to check this, a series of measurements was performed. Two multiprofilometry instruments were used - a contact profilometer, further equipped with an interferometric transducer, and an optical one with a confocal probe. Measurements were performed on first-class flat interferometric glass and on an A-type roughness standard - under different conditions, with simultaneous registration of differences in ambient temperature values. These values were either intentionally changed or the temperature variations were the result of air conditioning control. The performed research showed that - despite the asperities on the surface being really small - there is a relationship between changes of temperature and the results obtained from the measured surface, which in some cases can be seriously distorted.

Oviposition of Lymnaea truncatula infected by Fasciola hepatica under experimental conditions

1999 ◽  
Vol 85 (7) ◽  
pp. 589-593 ◽  
Author(s):  
G. Dreyfuss ◽  
D. Rondelaud ◽  
C. Vareille-Morel
Keyword(s):  
Fasciola Hepatica ◽  
Experimental Conditions ◽  
Lymnaea Truncatula
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