The effect of constant and changing temperatures on the development of the eggs and larvae of Oswaldocruzia filiformis (Nematoda: Trichostrongyloidea)

1988 ◽  
Vol 62 (4) ◽  
pp. 281-292 ◽  
Author(s):  
Christine T. Griffin
Keyword(s):  
Room Temperature ◽  
Rana Temporaria ◽  
Free Living ◽  
Temperature Changes ◽  
Larval Stages ◽  
The Third ◽  
Temperature Regimes ◽  
Frog Tadpoles ◽  
Eggs And Larvae ◽  
Duration Of Development

AbstractThe free-living stages of Oswaldocruzia filiformis were cultured in tapwater under constant and changing temperature regimes. Embryonation and hatching proceeded at constant temperatures from 6° to 32°C; development of larvae to the third (infective) stage occurred between 6° and 34°C. The duration of development decreased with increased temperatures up to 28°C. The duration of development of egg and larval stages under changing temperatures was compared with values predicted from constant temperature experiments. The rate of development of eggs to hatching was significantly accelerated under regimes of both sudden and gradual temperature changes. The effect of fluctuating temperatures on larval development was less consistent; both acceleration and retardation effects were recorded. Frog tadpoles (Rana temporaria) were experimentally infected with O. filiformis; early parasitic development proceeded significantly faster at room temperature than at 9–10°C.

Survival of the first-stage larvae and infective larvae of Bunostomum trigonocephalum Rudolphi, 1808

Parasitology ◽  
1965 ◽  
Vol 55 (3) ◽  
pp. 551-558 ◽  
Author(s):  
Bandana Narain
Keyword(s):  
High Temperatures ◽  
Low Temperatures ◽  
Room Temperature ◽  
Tap Water ◽  
Scientific Research ◽  
Research Committee ◽  
Free Living ◽  
Larval Stages ◽  
Infective Larvae ◽  
Laboratory Facilities

The free-living larval stages of Bunostomum trigonocephalum are better adapted to low temperatures than high temperatures. Most survived at 10°C.In tap water, 1st-stage larvae survived for 11 days at 0°C, 17 days at 5°C, 20 days at 10°C, 15 days at 15°C, 18 days at 20°C, 15 days at 25°C, 9 days at 30°C, 7 days at 34°C, 4 days at 35°C, 16 h at 40°C, 40 min at 45°C and 20 min at 50°C.In tap water infective larvae survived for 40 days at 0°C, 70 days at 5°C, 100 days at 10 and 15°C. 65 days at 20°C, 48 days at 25°C, 38 days at 30°C, 14 days at 34°C, 6 days at 35°C, 5 days at 40°C, 3 h at 45°C and 105 min at 50°C.In tap water at room temperature infective larvae survived for 26 days in January, 20 days in February, 21 days in March, 13 days in April, 10 days in May, 6 days in June, 9 days in July and August, 11 days in September, 12 days in October, 14 days in November and 17 days in December.I thank Professor M. B. Lal for his interest and for providing laboratory facilities in the Department of Zoology, University of Lucknow; Dr Premvati for guidance; and the Scientific Research Committee, U.P., India, for financial help.

Development of Syncuaria squamata (Linstow, 1883) (Nematoda: Acuarioidea) in ostracods (Ostracoda) and double-crested cormorants (Phalacrocorax auritus auritus)

1987 ◽  
Vol 65 (10) ◽  
pp. 2524-2531 ◽  
Author(s):  
P. L. Wong ◽  
R. C. Anderson
Keyword(s):  
Room Temperature ◽  
Gravid Female ◽  
Final Host ◽  
Mature Male ◽  
Phalacrocorax Auritus ◽  
Larval Stages ◽  
The Third ◽  
Third Stage ◽  
Cypridopsis Vidua ◽  
Freshwater Ostracods

Syncuaria squamata (Linstow) developed to the infective third stage in two species of freshwater ostracods (Cyclocypris ovum (Jurine) and Cypridopsis vidua (Muller)). At room temperature (19–21 °C) the first moult occurred 11 d and the second moult 18 d postinfection. In experimentally infected double-crested cormorants (Phalacrocorax auritus auritus (Lesson)) larval stages of S. squamata were found between folds of the proventriculus and underwent the third moult within 3.5 d and the fourth moult within 8 d postinfection. Mature male and gravid female worms were found under the gizzard lining at 29 d postinfection; some females were embedded in the gizzard musculature with their tails protruding into the lumen. First through fourth larval stages are described. Of 14 cormorants captured at 5 weeks of age from Pigeon Island, Lake Ontario, 13 (93%) were naturally infected with S. squamata. Five of these birds, 15 weeks or older when examined, harboured only mature male S. squamata. This suggests that female worms may become senescent before males. It is estimated that S. squamata has a life-span of about 4 months in its final host.

Crystal Structures of and Polarized Absorption-Spectroscopy in Racemic and Resolved [Ru(bpy)3] (ClO4)2 and [Zn(bpy)3] (ClO4)2Bpy=2,2'-Bipyridine

1995 ◽  
Vol 48 (5) ◽  
pp. 929 ◽  
Author(s):  
E Krausz ◽  
H Riesen ◽  
AD Rae
Keyword(s):  
Room Temperature ◽  
Energy Difference ◽  
Temperature Structure ◽  
Asymmetric Unit ◽  
Threefold Axis ◽  
Crystal Forms ◽  
The Third ◽  
Racemic Form ◽  
Ligand Charge Transfer ◽  
Dominant Influence

[Zn( bpy )3] (ClO4)2 and [ Ru ( bpy )3] (ClO4)2 are isomorphous in both their racemic and resolved crystal forms. The resolved materials are monohydrates and have a C 2, Z = 8, structure with two independent formula units on general sites in the asymmetric unit. The cations have the same chirality. The inherent threefold axis of each cation lies approximately parallel to the c axis. The unrelated racemic form has a C2/c, Z = 4, structure which is a commensurate modulation of a P3c1, Z = 2, parent structure, typified by the room-temperature structure of [ Ru ( bpy )3] (PF6)2. A primary, secondary and tertiary axis of P3c1 become the c, b and a axes respectively of C2/c, retaining a third of the symmetry elements of P3c1. The crystals grow as multiply contacted twins. This structure bas just one spectroscopic site with the cation lying on a twofold axis that passes through the metal and one of the bidendate ligands and relates the other two ligands to each other. This feature is particularly useful in the study of the optical spectroscopy of the metal-to- ligand charge transfer excitations of [ Ru ( bpy )3]2+ and related systems. A comparison of structural and spectral data indicates that the positions of the anions have a dominant influence on the relative energies of the metal-to- ligand excitations. An energy difference between excitations involving the two (lower-energy) equivalent ligands and the third ligand of the order of 800 cm-1 is indicated in both singlet and triplet regions for the racemic perchlorate. The absorption spectra of [ Ru ( bpy )3]2+and [Os( bpy )3]2+ in a number of crystalline hosts are compared and discussed.

Studies on the life-history of Bunostomum phlebotomum (Railliet, 1900), a hookworm parasite of cattle

Parasitology ◽  
1946 ◽  
Vol 37 (3-4) ◽  
pp. 192-201 ◽  
Author(s):  
J. F. A. Sprent
Keyword(s):  
Infective Larva ◽  
Stage Larva ◽  
Fourth Stage ◽  
Larval Stages ◽  
The Third ◽  
Third Stage ◽  
History Of ◽  
Time Required ◽  
Cutaneous Blood ◽  
Fourth Stage Larva

A description is given of the processes of copulation, formation of the egg and spermatozoon, cleavage, embryogeny and hatching in B. phlebotomum. These processes were found to be essentially similar to those in other strongyle nematodes.The anatomy of the first three larval stages is described and the observations of Conradi & Barnette (1908) and Schwartz (1924) were largely confirmed.Penetration of the skin of calves by the infective larva was observed histologically. The larvae were found to have reached the dermis within 30 min. and to have penetrated the cutaneous blood vessels within 60 min. of application to the skin. The larvae were found in the lung where the third ecdysis was in progress 10 days after penetration of the skin. A description is given of the growth of the third-stage larva in the lung, the changes which take place during the third ecdysis, and the anatomy of the fourth-stage larva.The fourth-stage larvae exsheath in the lungs and travel to the intestine. After a period of growth in which sexual differentiation takes place, the fourth ecdysis occurs and the adult parasite emerges. The time required for the attainment of maturity was found to be somewhere between 30 and 56 days after penetration of the skin.This paper was written at the Ministry of Agriculture and Fisheries Veterinary Laboratories, Wey-bridge, and the writer would like to express his gratitude to the Director, Prof. T. Dalling, also to Dr W. R. Wooldridge, chairman of the Council of the Veterinary Educational Trust for their help and encouragement. The writer's thanks are also due to Dr H. A. Baylis, Prof. R. T. Leiper and Dr E. L. Taylor for their advice and help on technical points, and to Mr R. A. O. Shonekan, African laboratory assistant, for his able co-operation.

The ecology of the free-living stages of Ostertagia circumcincta

Parasitology ◽  
1972 ◽  
Vol 64 (3) ◽  
pp. 451-460 ◽  
Author(s):  
T. E. Gibson ◽  
G. Everett
Keyword(s):  
Development Time ◽  
Grazing Management ◽  
Free Living ◽  
Faecal Output ◽  
Parasitic Gastroenteritis ◽  
Eggs And Larvae

The development and survival of the eggs and larvae of O. circumcincta was studied by spreading the daily faecal output of a sheep over a 2 m square grass plot for 1 week. Observations were carried out for 3 years on material spread at 4-weekly intervals and broadly similar results were obtained in each year. Development time was long in eggs placed outside in January, February, March, November and December. Yields of larvae were small and all were dead within 5 months. During the rest of the year development time was about 2 weeks, yields of larvae were high and larvae survived until July or August of the following year. The significance of these findings in devising systems of grazing management to control parasitic gastroenteritis is discussed.

The prediction of the cyclic mechanical behavior of stainless steel 304L at room temperature

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hala Messai ◽  
Salim Meziani ◽  
Athmane Fouathia
Keyword(s):  
Stainless Steel ◽  
Design Methodology ◽  
Room Temperature ◽  
Type Model ◽  
Good Prediction ◽  
304L Stainless Steel ◽  
Content Type ◽  
The Third ◽  
Chaboche Model

Purpose The purpose of this paper is to highlight the performance of the Chaboche model in relation to the database identification, tests with imposed deformations were conducted at room temperature on 304L stainless steel specimens. Design/methodology/approach The first two tests were performed in tension-compression between ±0.005 and ±0.01; in the third test, each cycle is composed of the combination of a compression tensile cycle between ±0.01 followed by a torsion cycle between ±0.01723 (non-proportional path), and the last, uniaxial ratcheting test with a mean stress between 250 MPa and −150 MPa. Several identifications of a Chaboche-type model were then performed by considering databases composed of one or more of the cited tests. On the basis of these identifications, the simulations of a large number of ratchet tests in particular were carried out. Findings The results present the effect of the optimized parameters on the prediction of the behavior of materials which is reported in the graphs, Optimizations 1 and 2 of first and second tests and Optimization 4 of the third test giving a good prediction of the increasing/decreasing pre-deformation amplitude. Originality/value The quality of the model's predictions strongly depends on the richness of the database used for the identification of the parameters.

Observations on the free-living stages of the stomach worm Haemonchus contortus

Parasitology ◽  
1963 ◽  
Vol 53 (3-4) ◽  
pp. 469-481 ◽  
Author(s):  
J. H. Rose
Keyword(s):  
Haemonchus Contortus ◽  
Free Living ◽  
Rate Of Development ◽  
Temperature And Humidity ◽  
Survival And Development ◽  
Effects Of Temperature ◽  
Eggs And Larvae ◽  
Heavy Mortality

Outdoor observations were made on the rate of development of the free-living stages of H. contortus at different times of the year, and on the migratory activities and longevity of the larvae in faeces, on herbage and in soil.The effects of temperature and humidity on the survival and development of eggs and larvae, both in faeces and when separated from the faeces, were studied in the laboratory.The results of these observations are discussed in relation to the heavy mortality of the free-living stages of H. contortus and to the transmission of infection in the field.

scholarly journals Predatory activity of Arthrobotrys oligospora and Duddingtonia flagrans on pre-parasitic larval stages of cyathostominae under different constant temperatures

2001 ◽  
Vol 31 (5) ◽  
pp. 839-842 ◽  
Author(s):  
Clóvis de Paula Santos ◽  
Terezinha Padilha ◽  
Maria de Lurdes de Azevedo Rodrigues
Keyword(s):  
Optimum Temperature ◽  
Duddingtonia Flagrans ◽  
Arthrobotrys Oligospora ◽  
Egg Development ◽  
Free Living ◽  
Predatory Activity ◽  
Larval Stages ◽  
Different Temperatures ◽  
Reduction Percentage

The effect of different temperatures on the predatory activity of Arthrobotrys oligospora and Duddingtonia flagrans on the free-living larval stages of cyathostomes were evaluated in an experiment where feces of horses containing the parasites’ eggs were treated with these fungi and incubated under different constant temperatures (10°C, 15°C, 20°C, 25°C and 30°C ). The results indicated that the optimum temperature for egg development was 25°C. At 10°C the number of L3 recovered was practically zero, and at 15°C and 20°C, the percentage of larvae recovered was less than 3% of the total number of eggs per gram of feces. When these cultures subsequently were incubated for an additional period of 14 days at 27°C, they allowed the development of L3. In all the cultures inoculated with fungi a significant reduction in the number of larvae was observed. When incubated at 25°C or 30°C, the fungi caused reductions above 90%, in the number of L3. The samples cultivated at 10°C, 15°C, 20°C, 25°C and 30°C, when incubated for an additional period of 14 days at 27°C the reduction percentage of larvae was above 90% for A. oligospora. However, the same did not occur for D. flagrans. Here a reduction percentage between 47.5% and 41.8% was recorded when the cultures were incubated at 10°C and 20°C, respectively. The two species of fungi tested showed to be efficient in reducing the number of L3 when mixed with equine feces and maintained at the same temperature for the development of larval pre-parasitic stages of cyathostomes.

scholarly journals Effect of LiNbO3 on the Electrocaloric Performance of 0.94BNT-0.06BT Ceramic Materials

2021 ◽  
Author(s):  
Jing Chen ◽  
lei Wu ◽  
Luanfan Duan ◽  
Dongren Liu
Keyword(s):  
Ceramic Material ◽  
Room Temperature ◽  
Ceramic Materials ◽  
Adiabatic Temperature ◽  
Cooling Effect ◽  
Material System ◽  
Temperature Changes ◽  
Cooling Temperature ◽  
Temperature Range

Abstract Considering that the electric refrigeration temperature range of 0.94BNT-0.06BT ceramic materials is 100 ~ 140℃, the electric refrigeration performance of the 0.94BNT-0.06BT ceramic material system was modified by LiNbO3 doping to reduce the cooling temperature. As a result, the refrigeration temperature range of the 0.94BNT-0.06BT ceramic material system was lowered to 25 ~ 80℃, achieving its cooling effect near room temperature, and in this temperature range, the adiabatic temperature changes ∆T > 0.6K.

scholarly journals Efficacy of Bacillus thuringiensis (Berliner) isolates on fig moth, Ephestia cautella (Walker) Larvae

2014 ◽  
Vol 11 (2) ◽  
pp. 943-951
Author(s):  
Baghdad Science Journal
Keyword(s):  
Bacillus Thuringiensis ◽  
Larval Stage ◽  
Filter Paper ◽  
Larval Instar ◽  
Ephestia Cautella ◽  
Larval Stages ◽  
The Third ◽  
Total Percentage ◽  
First Instar ◽  
Paper Method

The following dilution 5×10-1, 10-1, 10?2 , 10-3 gm/L for the indigenous isolate of Bacillus thuringiensis bacteria and the commercially isalate were used for experiments against the different stages of fig moth of E.cautella which exposed by filter paper method. The results showed that mortality of larval stages was increased with the increasing concentration of the biocide, in addition to increase in the mortality of the larval stages reached to the highest percentage in the third days of treatment of the larval stage in comparison with the first and second days of exposure. The results also showed that the sensitivity of larval stages was increased in first and second instars while reduced in the last instars .The high percentage of first instar mortality for the indigenous isolate in the concentration of 5×10-1 was 72.8% , while the low percentage of mortality showed in the concentration of 5×10-1 for the fifth instar larvae which was 13.3% in third days of treatment while a high percentage of mortality was showed for the first instar larvae for the commercially isulate in the concentration of 5×10-1 was 59.4% Furthermore, low percentage of mortality was shown in the concentration of 5×10-1 in fifth instar larval which was 8.3% in the third days of treatment. The results also showed that the indigenous isolated was more effective than the commercially produced bacteria for killing larval instars of fig moth E.cautella .The total percentage of larval instar mortality reached to 44.5 % after the third days of treatment in concentration 5×10-1 in the indigenous isolate , and it was 33.8 % in the commercially produced bacteria .

Sign in / Sign up

Export Citation Format

Share Document