Transmission of Dirofilaria ursi Yamaguti, 1941 (Nematoda: Onchocercidae) of black bears (Ursus americanus) by blackflies (Simuliidae)

1980 ◽  
Vol 58 (10) ◽  
pp. 1913-1922 ◽  
Author(s):  
Edward M. Addison
Keyword(s):  
Ursus Americanus ◽  
Morphological Changes ◽  
Prepatent Period ◽  
Malpighian Tubules ◽  
Black Bears ◽  
Infective Stage ◽  
The Third ◽  
Third Stage ◽  
Effects Of Temperature

Microfilariae of Dirofilaria ursi Yamaguti, 1941 from black bears (Ursus americanus) developed to the third stage in Simulium venustum Say and perhaps other simuliids but not in culicids, tabanids, and ceratopogonids. Malpighian tubules were the only site which supported development to the third stage. In blackflies held at 27 and 23 °C, D. ursi reached the third stage in 5 and 9 days respectively. At 18 °C larvae did not reach the third stage in blackflies held for 16 days.The effects of temperature (18, 23, and 27 °C) on growth of D. ursi in the vector are described. Morphological changes in larvae during development to the infective stage at 23 °C are reported. The prepatent period of D. ursi in black bears is 210–271 days.

Life cycle of Crenosoma petrowi (Nematoda: Metastrongyloidea) from black bears (Ursus americanus)

1994 ◽  
Vol 72 (2) ◽  
pp. 300-302 ◽  
Author(s):  
Edward M. Addison ◽  
Grant A. Fraser
Keyword(s):  
Life Cycle ◽  
Vulpes Vulpes ◽  
Ursus Americanus ◽  
Prepatent Period ◽  
Black Bears ◽  
Mephitis Mephitis ◽  
Red Foxes ◽  
The Third ◽  
Third Stage ◽  
Striped Skunks

First-stage larvae of Crenosoma petrowi Morozov, 1939 from feces of black bears (Ursus americanus) developed to the third stage in the gastropod Mesodon thyroidus. In snails held at 23.5 °C, the first and second moults occurred on days 6–7 and 9–11, respectively, after infection. The prepatent period of C. petrowi was 19–25 days in five experimentally infected black bears. Both times of first and second moults and the prepatent periods are similar among species of Crenosoma. Crenosoma petrowi did not produce patent infections in, and no nematodes were recovered from, experimentally infected striped skunks (Mephitis mephitis), raccoons (Procyon lotor), or red foxes (Vulpes vulpes).

Migration, growth, and morphogenesis of Dracunculus insignis (Nematoda: Dracunculoidea)

1975 ◽  
Vol 53 (2) ◽  
pp. 105-113 ◽  
Author(s):  
Vincent Frederick Joseph Crichton ◽  
Mary Beverley-Burton
Keyword(s):  
Quantitative Data ◽  
Subcutaneous Tissue ◽  
Abdominal Cavity ◽  
Final Host ◽  
Prepatent Period ◽  
Infective Stage ◽  
Infective Larvae ◽  
Third Stage ◽  
Migratory Route

Larvae of Dracunculus insignis developed to the infective stage in experimentally infected Cyclops vernalis and C. bicuspidatus thomasi kept at 24 C. The first molt occurred at 8–9 days and the second at 13–16 days. Second- and third-stage larvae are briefly described. Infective larvae were administered to raccoon (Procyon lotor) and mink (Mustela vison) and necropsies were performed at predetermined intervals for the determination of the migratory route. In raccoon, third-stage larvae were recovered from the gut wall and mesentery of the abdominal cavity on the 1st day. Larvae were found in the intercostal muscles by the 5th day and in the subcutaneous tissue of the thorax and abdomen by the 7th day. Development to fourth stage was complete by the 19th day. Sexual differences were apparent by the 34th day and worms were present in subcutaneous tissue of the thorax, abdomen, and inguinal region. Male worms were mature at 60 days and females at 65–70 days. Larvigerous females were found in the extremities as early as 120 days post infection. The prepatent period was 354 (309–410) days. Similar results were obtained from mink. Quantitative data on the distribution of worms in various locations within the final host at different times after infection are included.

Observations on the life history of the cat Lungworm. Aelurostrongylus abstrusus (Railliet, 1898) (Nematoda: Metastrongylidae)

1957 ◽  
Vol 5 (2) ◽  
pp. 188 ◽  
Author(s):  
MJ Mackerras
Keyword(s):  
Life History ◽  
Lung Tissue ◽  
Prepatent Period ◽  
The Body ◽  
Characteristic Pattern ◽  
Aelurostrongylus Abstrusus ◽  
The Third ◽  
Third Stage ◽  
History Of

First-stage larvae of Aelurostrongylus abstrusus (Railliet) developed readily in the garden slug, Agriolimax laevis (Muller), two moults occurring in this host. When infected slugs were eaten by a cat, the third-stage larvae migrated at once to the lungs, where they underwent the third and fourth moults. The prepatent period in the cat was about 39 days. When infected slugs were fed to laboratory-bred mice, the third-stage larvae were not digested, but congregated in great numbers in the gastro-splenic ligament, forming minute yellowish cysts. They were also recovered in small numbers from other parts of the body. Third-stage larvae survived unchanged in mice for 12 weeks, and probably would survive for longer periods. Mice were regarded as important auxillary hosts. The minute adult worms were found in the bronchioles of the cat. They were always very difficult to locate. The eggs were laid in the alveoli, forming a characteristic pattern of small, solid nodules scattered throughout the lung tissue.

scholarly journals Peculiarities of Embryonic and Post-Embryonic Development of Оesophagostomum dentatum (Nematoda, Strongylidae) Larvae Cultured in Vitro

2017 ◽  
Vol 51 (1) ◽  
pp. 67-72
Author(s):  
V. А. Yevstafieva ◽  
I. I. Panikar ◽  
V. V. Melnychuk ◽  
L. N. Korchan ◽  
N. A. Perederii
Keyword(s):  
Embryonic Development ◽  
Sus Scrofa ◽  
Infective Larva ◽  
Infective Stage ◽  
Optimum Temperature ◽  
Domestic Pig ◽  
The Third ◽  
Third Stage ◽  
Sus Scrofa Domesticus

Abstract Morphometric peculiarities of the development of Оesophagostomum dentatum Rudolphi, 1803 from egg to infective larva were studied under laboratory conditions at various temperatures. The determined optimum temperature for embryonic and post-embryonic development of О. dentatum larvae from domestic pig (Sus scrofa domesticus Linnaeus, 1758) is 22 °С. At this temperature, 81 % of larvae develop to the third stage (L3) on the 10th day. Temperatures of 24 °С and 20 °С are less favorable for the development of the nematode, at those temperatures only 67 and 63 % of larvae, respectively, reached infective stage by the 10th day of cultivation. Embryonic development of О. dentatum eggs is characterized by their lengthening (by 8.87-9.50 %, р < 0.01) and widening (by 6.77-9.35 %, р < 0.05-0.01), and post-embryonic larval development is associated with lengthening (by 4.59-17.33 %, р < 0.01-0.001).

Effects of temperature on hatching and development of Nematospiroides dubius in aerated water

1975 ◽  
Vol 49 (4) ◽  
pp. 293-296 ◽  
Author(s):  
R. Murua
Keyword(s):  
Minimum Time ◽  
The Third ◽  
Third Stage ◽  
Nematospiroides Dubius ◽  
Effects Of Temperature ◽  
Time Required

ABSTRACTFresh eggs obtained from female Nematospiroides dubius were cultured at temperatures ranging from 5°C to 33°C. Hatching occurred between 5°C and 30°C; third stage larvae were obtained between 5°C and 25°C. The minimum time required from hatching to development to the third stage was 3.6 days (at 20°C) and the maximum was seven days (at 5°C). Larvae cultured at higher temperatures were smaller than those cultured at lower ones.

THE EFFECTS OF TEMPERATURE ON THE SURVIVAL AND DEVELOPMENT OF THE FREE-LIVING STAGES OF TRICHOSTRONGYLUS RETORTAEFORMIS ZEDER (NEMATODA)

1961 ◽  
Vol 39 (1) ◽  
pp. 47-53 ◽  
Author(s):  
S. P. Gupta
Keyword(s):  
Escherichia Coli ◽  
Ambient Temperature ◽  
Infective Stage ◽  
Free Living ◽  
Infective Larvae ◽  
Third Stage ◽  
Survival And Development ◽  
Pure Cultures ◽  
Effects Of Temperature

The effects of temperature on the survival and development of the free-living stages of Trichostrongylus retortaeformis have been studied using agar cultures inoculated with pure cultures of Escherichia coli. The ova hatched and infective larvae developed at temperatures ranging from 5 °C to 30 °C, but 35 °C was lethal in 24 hours. The time of development of the larvae to the infective stage was inversely proportional to the ambient temperature between the limits of 10 °C and 30 °C. The longevity in water of third-stage larvae previously cultured at 20 °C, 25 °C, and 30 °C was studied at temperatures ranging from 5 °C to 40 °C.

The Coherence of Mary Barton: Romance, Realism, and Utopia

2015 ◽  
Vol 5 (3) ◽  
pp. 185-200
Author(s):  
Robert Z. Birdwell
Keyword(s):  
Thomas Carlyle ◽  
The Novel ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Three Stages ◽  
Mode Of Production

Critics have argued that Elizabeth Gaskell's first novel, Mary Barton (1848), is split by a conflict between the modes of realism and romance. But the conflict does not render the novel incoherent, because Gaskell surpasses both modes through a utopian narrative that breaks with the conflict of form and gives coherence to the whole novel. Gaskell not only depicts what Thomas Carlyle called the ‘Condition of England’ in her work but also develops, through three stages, the utopia that will redeem this condition. The first stage is romantic nostalgia, a backward glance at Eden from the countryside surrounding Manchester. The second stage occurs in Manchester, as Gaskell mixes romance with a realistic mode, tracing a utopian drive toward death. The third stage is the utopian break with romantic and realistic accounts of the Condition of England and with the inadequate preceding conceptions of utopia. This third stage transforms narrative modes and figures a new mode of production.

Bankruptcy Model Construction and its Limitation in Input Data Quality

2019 ◽  
Vol 10 (2) ◽  
pp. 117-125
Author(s):  
Dana Kubíčková ◽  
◽  
Vladimír Nulíček ◽  
Keyword(s):  
Data Quality ◽  
Normal Distribution ◽  
Input Data ◽  
Model Construction ◽  
The Third ◽  
Third Stage ◽  
Discriminant Analyses ◽  
One Year ◽  
The University ◽  
Multivariate Discriminant

The aim of the research project solved at the University of Finance and administration is to construct a new bankruptcy model. The intention is to use data of the firms that have to cease their activities due to bankruptcy. The most common method for bankruptcy model construction is multivariate discriminant analyses (MDA). It allows to derive the indicators most sensitive to the future companies’ failure as a parts of the bankruptcy model. One of the assumptions for using the MDA method and reassuring the reliable results is the normal distribution and independence of the input data. The results of verification of this assumption as the third stage of the project are presented in this article. We have revealed that this assumption is met only in a few selected indicators. Better results were achieved in the indicators in the set of prosperous companies and one year prior the failure. The selected indicators intended for the bankruptcy model construction thus cannot be considered as suitable for using the MDA method.

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