scholarly journals Morphological and Biological Characteristics of Amidostomum Anseris (Nematoda, Amidostomatidae) from Anser anser domesticus

2019 ◽  
Vol 53 (1) ◽  
pp. 65-74 ◽  
Author(s):  
V. А. Yevstafieva ◽  
V. V. Stybel ◽  
V. V. Melnychuk ◽  
О. В. Prijma ◽  
I. V. Yatsenko ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Infective Larva ◽  
Morphological Characteristics ◽  
Anser Anser ◽  
Size Dimorphism ◽  
Infective Larvae ◽  
Laboratory Conditions ◽  
Differential Characters ◽  
Species Specific ◽  
Amidostomum Anseris

Abstract Morphological characteristics were studied in adult and embryonic Amidostomum anseris (Zeder, 1800) obtained from domestic goose Anser anser domesticus Linnaeus, 1758. The studied characters included species-specific morphometric indices of male and female specimens and differential characters of sex-related dimorphism in that species. Stages and periods of embryonic development, and viability of the nematodes were studied at laboratory conditions. Size dimorphism in A. anseris was considerable, females were significantly larger (by 10.09–27.98 %) than males by 11 parameters. Additional metric characters were proposed to enhance effectiveness of differentiation of female and male A. anseris specimens. Under laboratory conditions, embryonic development of A. anseris occurs in four stages: blastomere cleavage; larval formation; formation of non-infective larvae I and II; formation of infective larva III which hatches from the egg. Infective larvae develop at 23 °С in six days, and their viability was up to 78.33 ± 2.08 %.

scholarly journals Species-specific morphological characteristics of adult and embryonic Capillariа obsignata roundworms (Nematoda, Capillariidae)

2018 ◽  
Vol 25 (4) ◽  
Author(s):  
V. A. Yevstafyeva ◽  
V. V. Stybel ◽  
T. A. Sharavara ◽  
V. V. Melnychuk ◽  
I. О. Yasnolob ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Adult Males ◽  
Meristic Characters ◽  
Morphometric Characters ◽  
Nematode Eggs ◽  
Males And Females ◽  
Species Specific ◽  
Shape And Size

The abundance of Capillaria obsignata Madsen, 1945, the causative agent of chicken capillariasis, was studied in the central region of Ukraine. Differential morphometric characters are determined for adult males and females of C. obsignata. The species-specific variability of its morphological parameters is characterized. New data is received on the meristic characters of C. obsignata eggs extracted from different substrates. The stages of embryonic development are determined in laboratory cultures of these nematodes, taking into account their meristic and morphological changes. Capillaria obsignata parasites are very common at the poultry farms of Poltava and Kyiv regions of Ukraine. Their abundance index is 3.4, and the intensity of infection varies from 3 to 317 specimens. Differential morphometric species-specific characters of adult C. obsignata males are the shape and size of the pseudobursa, spicule, spicule sheath. Adult females of the species can be identified by the shape and size of the vulva, the distance from the esophagus end to the vulva, and the length of the vagina. The meristic characters of nematode eggs, though typical for the species, may change depending on the sampled substrate. The parasite’s embryonic development involves five morphologically and meristically different stages. The invasive larvae of this species developed in the eggs before the 12th day of culturing in laboratory conditions at 25 °С. The invasive larvae’s viability was 90.3 ± 1.5%.

scholarly journals Comparative morphology and biology of nematodes of genus Heterakis (Nematoda, Heterakidae), parasites of the domestic goose (Anser anser) in Ukraine

2018 ◽  
Vol 9 (2) ◽  
pp. 229-236 ◽  
Author(s):  
V. A. Yevstafyeva ◽  
V. V. Melnychuk ◽  
О. V. Nikiforova ◽  
К. V. Suprunenko ◽  
L. N. Korchan ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Comparative Morphology ◽  
Laboratory Culture ◽  
Intensity Of Infection ◽  
Anser Anser ◽  
Abundance Index ◽  
Second Stage ◽  
Nematode Parasites ◽  
Morphological Differences ◽  
Species Specific

The genus Heterakis Dujardin, 1845 is one of the most widely distributed genera of nematode parasites of domestic and wild birds. Geographically and ecologically predominant species include Heterakis gallinarum Schrank, 1788 and Heterakis dispar Schrank, 1790. Prevalence and occurrence of these nematodes in the domestic goose (Anser anser dom.) depend on their biological and morphological specifics which ensure the highest viability, fast growth and maximum fertility in the host. This study presents the abundance and species composition of nematodes of the genus Heterakis in the domestic goose in Ukraine. Comparative study of morphological and metrical characteristics of H. gallinarum and H. dispar adult females and males is presented. Additional morphometric characteristics are proposed for easier identification of the two species. Stages and periods of embryonic development of H. gallinarum and H. dispar nematodes obtained from domestic geese are established according to morphological and metrical characters. Of the two species, H. dispar is prevalent in domestic geese from Poltava, Kharkiv and Kyiv regions. Abundance index of this species is 9.8 specimens, and intensity of infection index is up to 62 specimens. H. gallinarum is rarer, its abundance index is 1.2 specimens and maximum intensity of infection is 30 specimens. Species-specific morphological differences are more distinct in male nematodes in the size and structure of the spicules, lateral wing-like protrusions of pseudobursas, numbers and position of tail papillae. Additional metrical characteristics differ between H. gallinarum and H. dispar nematodes, allowing us to identify not only adult specimens but also eggs. Embryonic development of both species occurs in four morphologically distinct stages: protoplast, blastomere cleavage, formation of first and second stage larvae. Eggs of H. gallinarum nematodes become infectious in eight days at 27 °С, eggs of H. dispar in four days, their viability in laboratory culture is 84.3 ± 0.58 and 91.3 ± 1.53% respectively.

scholarly journals Embryonic development of the fire-eye-tetra Moenkhausia oligolepis (Characiformes: Characidae)

Zygote ◽  
2021 ◽  
pp. 1-5
Author(s):  
Raquel Santos dos Santos ◽  
Jeane Rodrigues Rodrigues ◽  
Jhennifer Gomes Cordeiro ◽  
Hadda Tercya ◽  
Marissol Leite ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Germ Cell ◽  
Cell Transplantation ◽  
Species Conservation ◽  
Biotechnological Applications ◽  
Model Species ◽  
Phylogenetic Classification ◽  
Laboratory Conditions ◽  
Adhesive Surface ◽  
Taxonomic Studies

Summary This study describes the embryonic development of Moenkhausia oligolepis in laboratory conditions. After fertilization, the embryos were collected every 10 min up to 2 h, then every 20 min up to 4 h, and afterwards every 30 min until hatching. The fertilized eggs of M. oligolepis measured approximately 0.85 ± 0.5 mm and had an adhesive surface. Embryonic development lasted 14 h at 25ºC through the zygote, cleavage, blastula, gastrula, neurula, and segmentation phases. Hatching occurred in embryos around the 30-somites stage. The present results contribute only the second description of embryonic development to a species from the Moenkhausia genus, being also the first for this species. Such data are of paramount importance considering the current conflicting state of this genus phylogenetic classification and may help taxonomic studies. Understanding the biology of a species that is easily managed in laboratory conditions and has an ornamental appeal may assist studies in its reproduction to both supply the aquarium market and help the species conservation in nature. Moreover, these data enable the use of M. oligolepis as a model species in biotechnological applications, such as the germ cell transplantation approach.

scholarly journals Characterization of the Bull's Eye Rot of Apple in Chile

Plant Disease ◽  
2013 ◽  
Vol 97 (4) ◽  
pp. 485-490 ◽  
Author(s):  
Sylvana Soto-Alvear ◽  
Mauricio Lolas ◽  
Inés M. Rosales ◽  
Eduardo R. Chávez ◽  
Bernardo A. Latorre
Keyword(s):  
Morphological Characteristics ◽  
The United States ◽  
Apple Fruit ◽  
Maritime Transportation ◽  
Tubulin Genes ◽  
Internal Transcribed Spacer Sequences ◽  
Apple Production ◽  
Species Specific ◽  
Bull's Eye

Apple fruit in Chile are primarily produced for export to Asia, Europe, and the United States, which typically requires 15 to 40 days of maritime transportation. Therefore, Chilean apple production must fulfill the sanitization requirements imposed by the receiving countries. Under these circumstances, it was important to clarify the etiology of bull's eye rot that can severely affect ‘Cripps Pink’ apple and other late-harvest cultivars in Chile. Based on morphological characteristics and the partial sequence analysis of the internal transcribed spacer sequences and β-tubulin genes, Neofabraea alba was identified as the causal agent of the bull's eye rot of Chilean apple. These results were further corroborated using species-specific primers. The incidence of bull's eye rot varied considerably; for instance, in 2009, 0.0 to 58.7% in 38 Cripps Pink orchards surveyed in the relatively arid and humid apple-growing areas of Chile, respectively. There was no evidence for the presence of N. malicorticis or N. perennans, which are commonly identified as causal agents of bull's eye rot in other apple-producing countries. Altogether, these data suggest that N. alba might represent the predominant and possibly the only cause of bull's-eye rot of Chilean apple.

scholarly journals First record of the semi-slug Omalonyx unguis (d’Orbigny, 1837) (Gastropoda, Succineidae) in the Misiones Province, Argentina

Check List ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 705-712
Author(s):  
Leila B. Guzmán ◽  
Enzo N. Serniotti ◽  
Roberto E. Vogler ◽  
Ariel A. Beltramino ◽  
Alejandra Rumi ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Morphological Characteristics ◽  
First Record ◽  
Coi Gene ◽  
Cytochrome Oxidase Subunit ◽  
Specific Identification ◽  
Molluscan Fauna ◽  
Misiones Province ◽  
Species Specific ◽  
Northeastern Argentina

Omalonyx unguis (d’Orbigny, 1837) is a semi-slug inhabiting the Paraná river basin. This species belongs to Succineidae, a family comprising a few representatives in South America. In this work, we provide the first record for the species from Misiones Province, Argentina. Previous records available for Omalonyx in Misiones were identified to the genus level. We examined morphological characteristics of the reproductive system and used DNA sequences from cytochrome oxidase subunit I (COI) gene for species-specific identification. These new distributional data contribute to consolidate the knowledge of the molluscan fauna in northeastern Argentina.

scholarly journals Occurrence and genetic similarity of Diplodia pinea on shoots and cones in seed orchards of Pinus spp. in north-western Turkey

2014 ◽  
Vol 50 (No. 4) ◽  
pp. 217-220
Author(s):  
H.T. Doğmuş-Lehtijärvi ◽  
A.G.A. Kaya ◽  
A. Lehtijärvi ◽  
F. Oskay ◽  
Ö.D. Kaya
Keyword(s):  
Disease Severity ◽  
Morphological Characteristics ◽  
Pinus Nigra ◽  
Marmara Region ◽  
Western Turkey ◽  
Seed Orchards ◽  
Diplodia Pinea ◽  
Shoot Blight ◽  
Species Specific ◽  
Pinus Spp

Diplodia shoot blight disease can cause significant damage on coniferous trees and be particularly injurious to cones, which reduces the amount of seed production and germination. We investigated the disease severity and genetic variation of Diplodia pinea in one Pinus nigra and two P. sylvestris seed orchards. Disease surveys were carried out in İzmit (Marmara region, Turkey) in May 2012. Symptomatic shoots and cones were examined for the presence of pycnidia. Cultural and morphological characteristics of the isolates were studied using cultures grown on potato dextrose agar (PDA). Based on morphological characteristics and results using species specific primers, the pycnidia on shoots and cones were identified as D. pinea. In addition, Random Amplified Microsatellite Sequence (RAMS) analyses indicated that there was a single genet of D. pinea which caused the disease in the seed orchards. All of the 60 sampled trees were found to be infected by the fungus. There were differences in disease severity among the stands.  

The Behaviour of sterilised exsheathed infective Trichostrongylid larvae in sterile media resembling their environment in Ovine hosts

1935 ◽  
Vol 13 (2) ◽  
pp. 115-128 ◽  
Author(s):  
Geoffrey Lapage
Keyword(s):  
Infective Larva ◽  
Physiological Study ◽  
Intestinal Cells ◽  
Distilled Water ◽  
Infective Larvae ◽  
The Third ◽  
Normal Environment ◽  
Parasitic Larva ◽  
At Will

1. Attempts were made to cultivate in sterile artificial media the sterilised first parasitic larva of intestinal nematodes of sheep. These larvae were obtained by artificial production of the second ecdysis in 1 in 20 dilutions of Milton hypochlorite in distilled water.2. Over 1,500 larvae were thus isolated, usually in hanging drops, in more than 200 different sterile media, containing ingredients likely to be present in the normal environment of these larvae inside their hosts.3. None of the larvae showed any growth. Most formed the next sheath and were ready for the third ecdysis, but only 10 larvae actually performed this. The parasitic third larva thus liberated always emerged by a rent at the side of the eosophageal region of the sheath, and never by detachment of a cap like that characteristic of the second ecdysis. In every instance the parasitic third larva died immediately after the third ecdysis, which set it free. Two of these 10 larvae underwent the second and third ecdyses simultaneously.4. The methods used by the writer (1933b) to induce artificially the second ecdysis always failed to produce the third ecdysis. No method of producing this at will was found.5. The longest time any first parasitic larva lived was 41 days. Few of them lived, however, less than 8–10 days. A life of 18–30 days was more usual before visible signs of physiological abnormality appeared, such as the gradual vacuolation and emptying of the intestinal cells which usually preceded their death.6. Those which were ready with a loose sheath for the third ecdysis, showed, as infective larvae also do, remarkable powers of resistance to changes produced in them by osmotic factors.7. None of the larvae showed any particular reaction to blood, mucosa of the stomach or duodenum, nor, indeed, to any of the ferments or tissues these larvae encounter in their hosts. They seemed to be as indifferent in this respect as the sheathed infective larvae are.8. A comparative physiological study of the sheathed infective and the exsheathed first parasitic phases of the second larva would verify, and perhaps modify, our knowledge of the functions of the so-called protective sheath of the infective larva.

Dynamics of gastropod infection by first-stage larvae of protostrongylid nematodes — a model

Parasitology ◽  
1993 ◽  
Vol 107 (5) ◽  
pp. 537-544 ◽  
Author(s):  
P. Řezáč ◽  
P. Kindlmann ◽  
I. Dostálková ◽  
E. Holasová
Keyword(s):  
Experimental Design ◽  
Infective Larva ◽  
Snail Infection ◽  
Instantaneous Rate ◽  
Rate Of Penetration ◽  
Susceptibility To Infection ◽  
Species Specific ◽  
Design Factors ◽  
Best Fit ◽  
Penetration Probability

SUMMARYFor the description of the dynamics of snail infection by the 1st-stage larvae of protostrongylid nematodes, Skorping (1988) used the miracidia-snail model (Anderson, 1978). Here it is shown that, in contrast to miracidia, in protostrongylids the instantaneous rate of infection, α, is strongly dependent on the experimental design (factors like host size and size of the experimental arena). With respect to this, Anderson's model is modified by incorporation of the experimental design. The parameter α in its new sense as the rate of penetration (probability that the infective larva will penetrate into the host during a time unit) is shown to remain dependent, although much less so, on the experimental design. Only the inclusion of the assumed effect of mucus, which decreases the rate of penetration, yields a parameter α0 (the initial rate of penetration), which is completely independent of the design of the experiment, is species-specific, and also gives the best fit to the empirical data. As the above-mentioned factors can strongly influence the value of the instantaneous rate of infection in the laboratory experiments, α0 is more suitable as a measure of either the larval infectivity for the snail or snail susceptibility to infection by the protostrongylid larvae.

scholarly journals The influence of desiccation and UV radiation on the development and survival of free-living stages of cyathostomins under field and laboratory conditions

2008 ◽  
Vol 45 (1) ◽  
pp. 32-40 ◽  
Author(s):  
I. Langrová ◽  
I. Jankovská ◽  
J. Vadlejch ◽  
M. Libra ◽  
A. Lytvynets ◽  
...  
Keyword(s):  
Uv Radiation ◽  
Field Experiments ◽  
The Other ◽  
Infective Stage ◽  
Free Living ◽  
Infective Larvae ◽  
Laboratory Conditions ◽  
Other Hand ◽  
Field And Laboratory Conditions

AbstractThe present work describing both laboratory and field experiments was performed to assess the effects of desiccation and UV radiation on the development and survival of free-living stages of equine cyathostomins.Cyathostomin larvae in horse faeces did not develop to the infective stage when faecal humidity levels dropped below 23 %, nonetheless solitary preinfective larvae were still recovered after 151 days (humidity 19.5 %). The development to infective stage after remoistening occurred for the last time after 54 days following desiccation.Preinfective stages are susceptible to the effects of the direct desiccation stage. The preinfective larvae were rapidly killed within one minute, the cyathostomin eggs within 5 hours. The numerous normal mobile infective larvae were encountered after 35 days of the desiccated period. The preinfective stage of cyathostomins also showed very little tolerance to direct sun radiation: most eggs were killed by the exposure within 3 hours and the preinfective larvae within 1 hour. The survival of infective larvae was, on the other hand, unaffected by sun radiation after 7 days (P < 0.05). However, desiccated infective larvae were then found to be susceptible to UV radiation, resulting in total mortalities after 5 days.

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