The effect of Trichostrongylus tenuis on the caecal mucosa of young, old and anthelmintic-treated wild red grouse, Lagopus lagopus scoticus

Parasitology ◽  
1987 ◽  
Vol 94 (2) ◽  
pp. 405-411 ◽  
Author(s):  
H. Watson ◽  
D. L. Lee ◽  
P. J. Hudson
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Disruption ◽  
Normal Functioning ◽  
Red Grouse ◽  
Lagopus Lagopus ◽  
Lagopus Lagopus Scoticus ◽  
Trichostrongylus Tenuis ◽  
Young Old ◽  
Scanning Electron

SUMMARYThe caecal mucosa of wild young and adult grouse infected naturally with Trichostrongylus tenuis was examined by means of scanning electron microscopy and compared with adult grouse which had been treated with an anthelmintic. The caecal mucosa of young red grouse with low worm burdens possessed longitudinal plicae and exhibited little damage. The caeca from adult grouse, most of which carried high worm burdens, showed a localized depression of plicae and atrophy and cell disruption in areas of nematode aggregation. Caeca from adult birds treated with an anthelmintic showed a similar caecal structure to lightly infected caeca from young birds. It is concluded that the normal functioning of the caeca is probably affected by heavy infections of T. tenuis.

The energetic consequences of parasitism: effects of a developing infection of Trichostrongylus tenuis (Nematoda) on red grouse (Lagopus lagopus scoticus) energy balance, body weight and condition

Parasitology ◽  
1995 ◽  
Vol 110 (4) ◽  
pp. 473-482 ◽  
Author(s):  
R. J. Delahay ◽  
J. R. Speakman ◽  
R. Moss
Keyword(s):  
Energy Balance ◽  
Resting Metabolic Rate ◽  
Red Grouse ◽  
Lagopus Lagopus ◽  
Energy Imbalance ◽  
Daily Energy ◽  
Total Daily Energy Expenditure ◽  
Synchronous Development ◽  
Lagopus Lagopus Scoticus ◽  
Trichostrongylus Tenuis

SUMMARYThe timing of the energetic consequences of a developing, single-dose infection of Trichostrongylus tenuis larvae was investigated in captive red grouse Lagopus lagopus scoticus. At 12 days post-infection (p.i.), infected birds had a resting metabolic rate 16% greater than controls and thenceforth lost weight at a faster rate than controls. At 16 days p.i. infected birds consumed 38% less energy and excreted 33% less energy than controls. The estimated total daily energy expenditure and energy expended on activity for infected birds at 16 days p.i. were 36% and 83% lower, respectively, than for controls. Infected birds lost condition from 16 days p.i. onwards. The period of energy imbalance at 12–16 days p.i. coincided with development of late 4th-stage larvae into adult worms and the onset of patency. After this, the effects on energy balance diminished. Synchronous development of previously arrested T. tenuis larvae in wild birds in spring probably has similar effects to those reported here and places grouse under conditions of energy imbalance. The observed effects on energy balance provide a possible mechanism by which the parasite can reduce fecundity and survival of infected grouse.

scholarly journals Morphological characterization of domatium development in Callicarpa saccata

2019 ◽  
Vol 125 (3) ◽  
pp. 521-532
Author(s):  
Emma Sarath ◽  
Kazune Ezaki ◽  
Takenori Sasaki ◽  
Yu Maekawa ◽  
Yuji Sawada ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Proliferation ◽  
Morphological Characterization ◽  
Leaf Primordia ◽  
Normal Functioning ◽  
Simple Leaf ◽  
Mesophyll Tissue ◽  
Scanning Electron

Abstract Background and aims Domatia are plant structures within which organisms reside. Callicarpa saccata (Lamiaceae) is the sole myrmecophyte, or ‘ant plant’, that develops foliar (leaf-borne) myrmeco-domatia in this genus. In this work we examined domatium development in C. saccata to understand the developmental processes behind pouch-like domatia. Methods Scanning electron microscopy, sectioning and microcomputed tomography were carried out to compare the leaves of C. saccata with those of the closely related but domatia-less myrmecophyte Callicarpa subaequalis, both under cultivation without ants. Key results Callicarpa saccata domatia are formed as a result of excess cell proliferation at the blade/petiole junctions of leaf primordia. Blade/petiole junctions are important meristematic sites in simple leaf organogenesis. We also found that the mesophyll tissue of domatia does not clearly differentiate into palisade and spongy layers. Conclusions Rather than curling of the leaf margins, a perturbation of the normal functioning of the blade/petiole junction results in the formation of domatium tissue. Excess cell proliferation warps the shape of the blade and disturbs the development of the proximal–distal axis. This process leads to the generation of distinct structures that facilitate interaction between C. saccata and ants.

Development and survival of the free-living stages of Trichostrongylus tenuis, a caecal parasite of red grouse Lagopus lagopus scoticus

Parasitology ◽  
1989 ◽  
Vol 99 (1) ◽  
pp. 105-113 ◽  
Author(s):  
J. L. Shaw ◽  
R. Moss ◽  
A. W. Pike
Keyword(s):  
Soil Surface ◽  
Winter Survival ◽  
Free Living ◽  
Red Grouse ◽  
Lagopus Lagopus ◽  
Infective Larvae ◽  
Surface Temperatures ◽  
The Mean ◽  
Lagopus Lagopus Scoticus ◽  
Trichostrongylus Tenuis

SUMMARYIn the laboratory, yields of infective 3rd-stage larvae of Trichostrongylus tenuis were determined by temperature when moisture was adequate. On the moor, eggs in caecal faeces did not develop to infective larvae during the winter. In summer, development did occur and yields of infective larvae were related to temperature: greatest yields were obtained when mean monthly soil surface temperatures ranged between 76 and 103°C. Rainfall was unimportant, as was desiccation. During summer the mean monthly mortality of infective larvae was 44% but over winter survival was negligible.

Faecal egg counts provide a reliable measure of Trichostrongylus tenuis intensities in free-living red grouse Lagopus lagopus scoticus

2004 ◽  
Vol 78 (1) ◽  
pp. 69-76 ◽  
Author(s):  
L.J. Seivwright ◽  
S.M. Redpath ◽  
F. Mougeot ◽  
L. Watt ◽  
P.J. Hudson
Keyword(s):  
Storage Time ◽  
Free Living ◽  
Red Grouse ◽  
Lagopus Lagopus ◽  
Counting Methods ◽  
Faecal Egg Counts ◽  
Lagopus Lagopus Scoticus ◽  
Trichostrongylus Tenuis ◽  
High Parasite ◽  
Exact Relationship

AbstractThe reliability of different egg counting methods for estimating the intensity of Trichostrongylus tenuis infections in red grouse, Lagopus lagopus scoticus, was investigated in the autumn, when grouse may harbour high parasite intensities. Possible limitations to the use of these methods were also examined. Faecal egg counts were found to accurately estimate T. tenuis worm intensities, at least up to an observed maximum of c. 8000 worms. Two egg counting methods (smear and McMaster) gave consistent results, although the exact relationship with worm intensity differed according to the method used. Faecal egg counts significantly decreased with increasing length of sample storage time, but egg counts were reliable for estimating worm intensity for three weeks. The concentration of eggs in the caecum was also found to reliably estimate worm intensity. However, egg counts from frozen gut samples cannot be used to estimate worm intensities. These results conclude that, despite some limitations, faecal and caecum egg counts provide useful and reliable ways of measuring T. tenuis intensities in red grouse.

scholarly journals Scanning Electron Microscopy as a Useful Tool for Monitoring Cell Disruption of Recombinant Escherichia coli SHuffle T7

2020 ◽  
Vol 26 (S1) ◽  
pp. 145-146
Author(s):  
Alina Falero ◽  
Yunier Serrano ◽  
Sandra Rodríguez ◽  
Susana Brito ◽  
Elsa Pimienta ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Scanning Electron Microscopy ◽  
Cell Disruption ◽  
Recombinant Escherichia Coli ◽  
Scanning Electron

Factors affecting the establishment of the caecal threadwormTrichostrongylus tenuisin red grouse (Lagopus lagopus scoticus)

Parasitology ◽  
1989 ◽  
Vol 99 (2) ◽  
pp. 259-264 ◽  
Author(s):  
J. L. Shaw ◽  
R. Moss
Keyword(s):  
Single Dose ◽  
Seasonal Variations ◽  
Red Grouse ◽  
Lagopus Lagopus ◽  
Factors Affecting ◽  
Infective Larvae ◽  
Lagopus Lagopus Scoticus ◽  
Trichostrongylus Tenuis

SummaryThe resistance of captive reared red grouse toTrichostrongylus tenuiswas measured as the proportion of ingested infective 3rd-stage larvae which failed to develop to adult worms. Individual grouse showed wide, repeatable variations in resistance. Seasonal variations may also have occurred. Red grouse acquired little or no effective immunity to reinfection after challenge with a single dose of infective larvae. In trickle-dosed grouse, however, adult worms weakly inhibited the establishment of incoming larvae in an intensity-dependent fashion. Despite this, the proportion of larvae established in trickle infections was similar to that in single-dose challenges.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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