Factors influencing development of free-living generations of Strongyloides stercoralis

Parasitology ◽  
1988 ◽  
Vol 97 (1) ◽  
pp. 129-138 ◽  
Author(s):  
K. Shiwaku ◽  
Y. Chigusa ◽  
T. Kadosaka ◽  
K. Kaneko
Keyword(s):  
High Temperature ◽  
Incubation Temperature ◽  
Strongyloides Stercoralis ◽  
Test Tube ◽  
Paper Test ◽  
Free Living ◽  
Factors Influencing ◽  
Prednisolone Treatment ◽  
Duration Of Infection ◽  
Incubation Temperatures

SUMMARYThe effects of duration of infection and of temperature and nourishment in cultures on development of free-living generations of Strongyloides stercoralis were studied quantitatively. Rhabditiform larvae, 228–353 μm long, were collected from infected dogs with or without prednisolone treatment using the Baermann apparatus. Cultures were carried out by the filter paper test-tube method under the following conditions: incubation temperature 15–40°C and faecal dilution 1:0–1:16. Rhabditiform larvae developed predominantly to free-living females at incubation temperatures of 15–30°C and low faecal dilutions, but filariform larvae appeared mainly under extreme conditions such as high temperature. Recovery rates of filariform larvae were inversely related to those of females. It was remarkable that high temperature, but not low faecal dilution, affected development of filariform larvae. Although the appearance of free-living males was constant in various environmental conditions, the present study indicated an increase in free-living males with the duration of infection. Thus, it seems that free-living males are already fixed as male in the egg stage, and potential female rhabditiform larvae differentiate into free-living females or filariform larvae depending on environmental factors. There is no marked difference in the development of rhabditiform larvae into filariform larvae in either the immunosuppressed dog or the intact dog.

scholarly journals Long-term consequences of high incubation temperature in a wild bird population

2016 ◽  
Vol 12 (4) ◽  
pp. 20160087 ◽  
Author(s):  
Andreas Nord ◽  
Jan-Åke Nilsson
Keyword(s):  
High Temperature ◽  
Body Mass ◽  
Incubation Temperature ◽  
Temperature Treatment ◽  
High Temperature Treatment ◽  
Bird Population ◽  
Biologically Relevant ◽  
Faster Development ◽  
Incubation Temperatures

Because incubation by birds is energetically costly, parents frequently trade off investment in incubation against self-maintenance. This can be manifested by a reduction in incubation temperature, which comes at high somatic costs for nestlings. The extent to which these costs constrain fitness is poorly understood. We incubated wild blue tit clutches at three biologically relevant temperatures and subsequently recorded winter survival and survival to the breeding season. Fledglings from the coldest treatment (35.0°C) survived less well than other fledglings, but the proportion of winter and breeding survivors did not differ significantly between treatments. However, survival probability in both seasons increased with body mass at fledging in birds from low and mid incubation temperatures, but decreased with fledging body mass in the high-temperature treatment. Mid-temperature nestlings were heavier as adults, weighing 7% more than low- and high-temperature survivors. Thus, high incubation temperature can be beneficial in the short term, but costs of accelerated embryonic development may equal those of protracted development in the long term. Such hidden consequences of faster development could maintain natural selection for average incubation temperature.

The effect of high temperature incubation upon the myocardial glycogen in the chick embryo

Development ◽  
1965 ◽  
Vol 14 (3) ◽  
pp. 273-280
Author(s):  
John M. Delphia ◽  
John Elliott
Keyword(s):  
High Temperature ◽  
Chick Embryo ◽  
Incubation Temperature ◽  
Growth Stages ◽  
Chick Embryos ◽  
One Stage ◽  
Accelerate Growth ◽  
Small Intestines ◽  
Incubation Temperatures

Numerous studies have shown that high temperature incubation for the chick embryo will accelerate growth. Ancel & Lallemand (1941) reported that, with incubation temperatures of 39·0 to 42·0°C. during the 3rd through the 6th day of incubation, 49·2 per cent, to 62·7 per cent, of the specimens expressed Coelosomia. This malformation is characterized by the eventration of the viscera through a body cleft. Delphia & Eveleth (1961) found that continuous incubation of chick embryos at 40·0°C. resulted in Coelosomia of the heart, liver, ventriculus and small intestines in 63 per cent, of the specimens. Further studies by Delphia (1963) indicated that, with a continuous incubation temperature of 40·0°C, the embryos were advanced in growth stages (Hamburger-Hamilton, 1951) by one stage and were 1·3 times heavier than normally incubated specimens at 8 days incubation. At this time (8 days incubation) coelosomia is demonstrated clearly.

AMEBAS PATÓGENAS DE VIDA LIBRE DEL GÉNERO ACANTHAMOEBA EN AGUAS RECREATIVAS EN LA HUASTECA POTOSINA, MÉXICO

2014 ◽  
Vol 7 ◽  
Author(s):  
Ricardo Ortiz Ortega ◽  
Alonso Vilches Flores ◽  
Marco Aurelio Rodríguez Monroy ◽  
Patricia Bonilla Lemus
Keyword(s):  
High Temperature ◽  
Water Body ◽  
Tropical Climate ◽  
Dry Season ◽  
Thermal Waters ◽  
Free Living ◽  
Severe Infections ◽  
Amebic Encephalitis ◽  
Animal Tests

Studies accomplished in freshwater demonstrate the importance of identify the presence of<br />protozoa like free living amoebae (FLA). In particular, the genera Acanthamoeba is associated with<br />severe infections in man, as the Granulomatous Amebic Encephalitis (GAE). The most important<br />factor for the development of these organisms is the high temperature of the water body. The<br />region of the Huasteca Potosina in Mexico, with a tropical climate and great aquatic resorts, like<br />rivers, waterfalls and pools of thermal waters, that allows the development of amoebae. In this<br />study we evaluated the presence of amoebas in the most visited places on the Huasteca Potosina.<br />Samples of a liter were taken in nine sites during the rainy and dry season. 54 strains of amoebas<br />were identify, 46 belong to the genera Acanthamoeba, resulting 30 of them pathogenic in the<br />animal tests. The pathogenic isolated amoebas were present in the most attended resorts by the<br />people in the waterfalls or pools of the places sampling. Temperature turned out to be the most<br />important factor for the presence of amoebae.

Phytotoxic Effect of Decaying Quackgrass (Agropyron repens) Residues

Weed Science ◽  
1979 ◽  
Vol 27 (6) ◽  
pp. 595-598 ◽  
Author(s):  
T. V. Toai ◽  
D. L. Linscott
Keyword(s):  
Incubation Temperature ◽  
Soil Surface ◽  
Water Soluble ◽  
Water Extracts ◽  
Phytotoxic Activity ◽  
Phytotoxic Effect ◽  
Effects Of Temperature ◽  
Incubation Temperatures ◽  
Toxin Formation ◽  
Agropyron Repens

We studied the effects of temperature (5, 10, 20, and 30 C) on the phytotoxic activity of decaying quackgrass [Agropyron repens (L.) Beauv.] leaves and rhizomes that were incubated in soils for 0, 1, 2, 4, and 6 weeks. Alfalfa (Medicago sativa L.) seeds were grown for 96 h in water, water extracts of control soils, and water extracts of soil with quackgrass rhizomes or leaves. Dried quackgrass rhizomes and leaves contained water-soluble toxins that inhibited alfalfa seedling development and growth. There was a strong interaction between incubation time and temperature on the development of additional toxins by decomposing quackgrass. High incubation temperature (30 C) accelerated toxin formation and ultimate decay. Intermediate temperature (20 C) delayed toxin formation and decay. Low incubation temperatures (5 C and 10 C) prevented formation of additional toxin. In all extracts of quackgrass and soil that had been incubated for 6 weeks, normal alfalfa seedling number equaled that in water. However, seedling growth varied with incubation temperatures.Treatment of quackgrass with glyphosate [N-(phosphonomethyl) glycine] in the greenhouse did not influence the toxicity of decaying quackgrass leaves. The highest toxic effect was noted after 1 week of decay on the soil surface.

Thermal and water source effects upon the stability of enteroviruses in surface freshwaters

1989 ◽  
Vol 35 (4) ◽  
pp. 474-480 ◽  
Author(s):  
Christon J. Hurst ◽  
William H. Benton ◽  
Kim A. McClellan
Keyword(s):  
Bacterial Growth ◽  
Incubation Temperature ◽  
Water Source ◽  
Inactivation Rate ◽  
Human Enterovirus ◽  
Strongly Correlated ◽  
Artificial Lake ◽  
Viral Inactivation ◽  
Term Survival ◽  
Incubation Temperatures

The long-term survival of three human enterovirus serotypes, Coxsackievirus B3, echovirus 7, and poliovirus 1 was examined in samples of surface freshwater collected from five sites of physically different character. These were an artificial lake created by damming a creek, a small groundwater outlet pond, both a large- and a medium-sized river, and a small suburban creek. Survival was studied at temperatures of −20, 1, and 22 °C. The average amount of viral inactivation was 6.50–7.0 log10 units over 8 weeks at 22 °C, 4–5 log10 units over 12 weeks at 1 °C, and 0.4–0.8 log10 units over 12 weeks at −20 °C. The effect of incubation temperature upon viral inactivation rate was statistically significant (p < 0.00001). As determined by pairing tests, survival was also significantly related to both viral serotype and water source at each of the three incubation temperatures (p ≤ 0.05). Efforts were made to determine whether the rate of viral inactivation observed at the different incubation temperatures was related to characteristics inherent to the water that was collected from the different locations. The characteristics examined included physical and chemical parameters, indigenous bacterial counts, and the amount of bacterial growth that the waters would support (measured as the maximum number of generations which seeded bacteria could undergo after being placed into either pasteurized or sterile-filtered water samples). Analysis of viral inactivation rate versus these characteristics revealed three apparent effectors of viral persistence. These were (i) hardness and conductivity, both of which strongly correlated with one another; (ii) turbidity and suspended solids content, both of which strongly correlated with one another; and (iii) the number of generations of bacterial growth that a sample was capable of supporting, which also correlated with hardness and conductivity.Key words: virus, survival, inactivation rate, water.

Nest temperature´s influence on morphology of Dermochelys coriacea hatchlings incubated in hatcheries in Oaxaca, Mexico

2021 ◽  
Author(s):  
Jesús García-Grajales ◽  
Juan Francisco Meraz ◽  
José Luis Arcos García ◽  
Eustacio Ramírez Méndez
Keyword(s):  
Incubation Temperature ◽  
Carapace Width ◽  
Principal Component ◽  
Dermochelys Coriacea ◽  
Egg Mass ◽  
Natural Environments ◽  
Data Logger ◽  
Geometric Morphometric ◽  
Low Weight ◽  
Incubation Temperatures

The influence of nest incubation temperatures on the carapace shape and morphological traits of Dermochelys coriacea (Vandelli 1761) hatchlings incubated in two hatcheries of Oaxaca, Mexico was evaluated. This study was carried out from October 2016 through May 2017. On each beach, there are community groups consisting of volunteers without association with universities, that protect and relocate the nests to increase hatching success. In each translocated nest, a data logger was placed in the centre of the egg mass. Hatchlings were collected as they emerged from each nest. The carapaces of the hatchlings were photographed and subjected to geometric morphometric analysis; later, hatchlings were weighed and their bodies were measured. The mean temperature of 12 nests in each hatchery were recorded, with no significant differences between hatcheries. The principal component analysis (PCA) revealed an overlapping of the carapace shape under different duration of temperature. Temperature had a significant influence on hatchling morphology. Higher mean incubation temperatures produced hatchlings with low weight, smaller appendage; narrower carapace width and shorter flippers length. Lower mean incubation temperatures produced hatchlings that had greater weight, greater appendage width, wider carapace width and longer flipper length. Results indicate that the D. coriacea hatchlings incubated in hatcheries demonstrate morphology that varies in relation to nest incubation temperature in a similar way to hatchlings produced in natural environments.

scholarly journals Assessment of factors influencing surface recrystallisation during high temperature exposure of fine-grained PM 2000 alloy

2007 ◽  
Vol 471 (1-2) ◽  
pp. 120-124 ◽  
Author(s):  
J.L. González-Carrasco ◽  
J. Chao ◽  
C. Capdevila ◽  
J.A. Jiménez ◽  
V. Amigó ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperature Exposure ◽  
Fine Grained ◽  
Factors Influencing ◽  
Temperature Exposure

Observation of the Free-living Adults of Strongyloides stercoralis from a Human Stool in Korea

2009 ◽  
Vol 41 (2) ◽  
pp. 105 ◽  
Author(s):  
Young-Hee Hong ◽  
Jong-Wan Kim ◽  
In-Soo Rheem ◽  
Jae-Soo Kim ◽  
Suk-Bae Kim ◽  
...  
Keyword(s):  
Strongyloides Stercoralis ◽  
Free Living ◽  
Human Stool

Factors influencing the distribution of Egregia menziesii (Phaeophyta, Laminariales) in British Columbia, Canada

1978 ◽  
Vol 56 (9) ◽  
pp. 1198-1205 ◽  
Author(s):  
D. K. Gordon ◽  
R. E. DE Wreede
Keyword(s):  
British Columbia ◽  
High Temperature ◽  
Laboratory Experiments ◽  
Algal Flora ◽  
The West ◽  
Common Component ◽  
Strait Of Georgia ◽  
Low Salinity ◽  
Factors Influencing ◽  
Juan De Fuca

Egregia menziesii (Turner) Areschoug is a common component of the algal flora along the west coast of Vancouver Island, Queen Charlotte Strait, and the Strait of Juan de Fuca but is absent from the Strait of Georgia in British Columbia, Canada. This distribution pattern was found to be correlated with temperature and salinity in that E. menziesii is not present in areas where there are seasonal periods of low salinity and high temperature. To test this correlation, field transplants of sporophytes and laboratory experiments with sporophytes and culture work were carried out. The results suggest that the distribution of E. menziesii is limited by specific combinations of salinity and temperature; it requires high salinities and temperatures less than 15 °C for its survival.

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