Infectivity, Growth, and Development of Parorchis acanthus (Trematoda) in the Domestic Chick

New molluscan, crustacean, and avian hosts were found for four species of digenetic trematodes in Vancouver, British Columbia, from 1973 to 1977. The rediae and cercariae of Parorchis acanthus (Nicoll) were discovered in Nucella lamellosa (Gmelin). Adults were recovered after 19 days from experimental feedings of the metacercariae to a newly hatched domestic chick. The cercariae of Cryptocotyle lingua (Creplin) from the snail Littorina scutulata Gould were used to infect young fish, Leptocottus armatus Girard, Oligocottus maculosus Girard, and Platichthys stellatus (Pallas). These fish, infected with the metacercariae, were fed to newly hatched gulls, Larus glaucescens Naumann, and mature worms were found in the anterior half of the intestine after 14 and 21 days. The metacercariae of Maritrema megametrios Deblock and Rausch, found in Orchestia traskiana Stimpson and Gnorimosphaeroma oregonense (Dana), became ovigerous in Locke's solution at 40 °C at 48 h. Natural infections were found in Larus Philadelphia (Ord). The metacercariae of Maritrema gratiosum Nicoll, found in Balanus glandula Darwin, also became ovigerous in vitro. Adults were found with two other microphallid species in the intestine of one Bucephala islandica (Gmelin).

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Infectivity, growth and development of Echinostoma revolution (Trematoda) in the domestic chick

Journal of Helminthology ◽

10.1017/s0022149x0002705x ◽

1984 ◽

Vol 58 (3) ◽

pp. 241-244 ◽

Cited By ~ 11

Author(s):

Bernard Fried

Keyword(s):

Body Length ◽

Growth And Development ◽

Domestic Chick ◽

The Body ◽

Bursa Of Fabricius ◽

Echinostoma Revolutum ◽

Domestic Chicks ◽

Excretory Bladder ◽

Length Measurements

ABSTRACTInfectivity, growth and development were studied in 23 one-day-old domestic chicks each fed 25 pre-selected metacercarial cysts of Echinostoma revolutum. All chicks were infected at necropsy one to 44 days postexposure with one to 18 flukes/chick. From the 575 cysts fed to chicks, 145 (25%) flukes were recovered from the ileum, caeca, rectum-cloaca and bursa of Fabricius. Length measurements on 113 uncurled flukes fixed in hot alcohol-formalin-acctic acid showed that worms grew slowly to 1.0 mm by day 3, rapidly to 6 mm by day 14, and less rapidly to 9 mm by day 36. Worms became ovigcrous by day 9. As worms aged in the chick, the body length increased relative to the width, the acetabulum shifted more antcriad and the size of the excretory bladder increased.

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Host–parasite relationships of Zygocotyle lunata (Trematoda) in the domestic chick

Parasitology ◽

10.1017/s003118200004871x ◽

1978 ◽

Vol 77 (1) ◽

pp. 49-55 ◽

Cited By ~ 15

Author(s):

B. Fried ◽

P. D. Nelson

Keyword(s):

Post Infection ◽

Protease Activity ◽

Growth And Development ◽

Domestic Chick ◽

Mucosal Tissue ◽

Acid Mucopolysaccharides ◽

Host Parasite ◽

Sexually Mature ◽

Histopathological Effects ◽

Single Worm

SummaryDomestic chicks were infected with Zygocotyle lunata to determine gross and histopathological effects on the caecal tissues, to observe the method of feeding by worms and to examine the effects of crowding on the growth and development of the worm. Caecal weights and dimensions were significantly reduced in infected chicks. Caecal debris, abundant in control chicks, stained positive for proteins, polysaccharides, acid mucopolysaccharides and neutral fats. Caecal debris was rarely seen in infected chicks. The lumen of the intestinal caeca of the worms contained acellular material which showed protease activity and stained positive for proteins, polysaccharides and acid mucopolysaccharides. Histopathological effects of the infection showed a disruption of the architecture of host caecal mucosa, worm to worm attachment, tissue plugs in the worm acetabulum, and an engorgement of host mucosal tissue with erythrocytes. Stunting due to worm crowding was very evident and by 2 weeks post-infection, worms from single-worm infections were sexually mature and more than twice the length of immature flukes obtained from chicks infected with 100–500 cysts.

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Growth, development and pairing of Leucochloridiomorpha constantiae (Trematoda) metacercariae on the chorio-allantois of chick embryos cultivated in vitro

Parasitology ◽

10.1017/s0031182000055025 ◽

1980 ◽

Vol 81 (1) ◽

pp. 41-45 ◽

Cited By ~ 6

Author(s):

B. Fried ◽

R. H. Fine ◽

Barbara L. Felter

Keyword(s):

Growth And Development ◽

Domestic Chick ◽

Bursa Of Fabricius ◽

Multiple Infections ◽

Chick Embryos ◽

Body Area ◽

The Mean ◽

Growth Development ◽

Sexually Mature

SUMMARYA simple in vitro technique was devised to culture chick embryos in Petri dishes from the 4th to the 21st day of incubation. Leucochloridiomorpha constantiae (Trematoda) metacercariae were placed either singly or multiply (5/embryo) on the chorio-allantois of in vitro grown embryos on day 7 and were removed on day 14. Growth and development studies were also made on worms grown singly or multiply (5/chick) in the bursa of Fabricius of the domestic chick. Worms grown singly or multiply in embryos were sexually mature, although eggs from these worms were abnormal when compared with eggs from worms recovered from chicks. The mean body area of worms from chicks was 2–3 times greater than that of worms from embryos. The mean body area of single worms from embryos was significantly larger than that of worms grown multiply in this site. However, the mean body area of multiple worms from the chick was significantly larger than that of single worms from this site. Worm pairs or clusters were seen in all embryos with the multiple infections.

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An ultrastructural study of vegetative incompatibility in plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083047 ◽

1978 ◽

Vol 36 (2) ◽

pp. 436-437

Author(s):

Randy Moore

Keyword(s):

Ultrastructural Study ◽

Cell Walls ◽

Growth And Development ◽

Solanum Pennellii ◽

Initial Product ◽

Basic Aspect ◽

Tissue Interactions ◽

Graft Interface ◽

Antigen Antibody ◽

Standard Fixation

Cell and tissue interactions are a basic aspect of eukaryotic growth and development. While cell-to-cell interactions involving recognition and incompatibility have been studied extensively in animals, there is no known antigen-antibody reaction in plants and the recognition mechanisms operating in plant grafts have been virtually neglected.An ultrastructural study of the Sedum telephoides/Solanum pennellii graft was undertaken to define possible mechanisms of plant graft incompatibility. Grafts were surgically dissected from greenhouse grown plants at various times over 1-4 weeks and prepared for EM employing variations in the standard fixation and embedding procedure. Stock and scion adhere within 6 days after grafting. Following progressive cell senescence in both Sedum and Solanum, the graft interface appears as a band of 8-11 crushed cells after 2 weeks (Fig. 1, I). Trapped between the buckled cell walls are densely staining cytoplasmic remnants and residual starch grains, an initial product of wound reactions in plants.

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Identification of calcium oxalate crystals in dried or fixed tobacco leaf

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111550 ◽

1984 ◽

Vol 42 ◽

pp. 288-289

Author(s):

Vicki L. Baliga ◽

Mary Ellen Counts

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Oxalate ◽

Growth And Development ◽

Polarized Light ◽

Calcium Oxalate Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

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SEM study of the morphological effects of kinetin and zeatin on the growth and development of the apical meristem in wheat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141263 ◽

1995 ◽

Vol 53 ◽

pp. 978-979

Author(s):

G. M. Hutchins ◽

J. S. Gardner

Keyword(s):

Growth And Development ◽

Furfuryl Alcohol ◽

Apical Meristem ◽

Plant Cells ◽

Triticum Aestivum L ◽

Morphological Development ◽

Naturally Occurring ◽

Chinese Spring Wheat ◽

Sem Study ◽

Moist Environment

Cytokinins are plant hormones that play a large and incompletely understood role in the life-cycle of plants. The goal of this study was to determine what roles cytokinins play in the morphological development of wheat. To achieve any real success in altering the development and growth of wheat, the cytokinins must be applied directly to the apical meristem, or spike of the plant. It is in this region that the plant cells are actively undergoing mitosis. Kinetin and Zeatin were the two cytokinins chosen for this experiment. Kinetin is an artificial hormone that was originally extracted from old or heated DNA. Kinetin is easily made from the reaction of adenine and furfuryl alcohol. Zeatin is a naturally occurring hormone found in corn, wheat, and many other plants.Chinese Spring Wheat (Triticum aestivum L.) was used for this experiment. Prior to planting, the seeds were germinated in a moist environment for 72 hours.

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Mechanisms of ethylene biosynthesis and response in plants

Essays in Biochemistry ◽

10.1042/bse0580061 ◽

2015 ◽

Vol 58 ◽

pp. 61-70 ◽

Cited By ~ 11

Author(s):

Paul B. Larsen

Keyword(s):

Plant Growth ◽

Growth And Development ◽

Ethylene Biosynthesis ◽

Unsaturated Hydrocarbon ◽

Flower Senescence ◽

Detailed Knowledge ◽

Plant Growth And Development ◽

Step Process ◽

Ethylene Response ◽

Ethylene Signalling

Ethylene is the simplest unsaturated hydrocarbon, yet it has profound effects on plant growth and development, including many agriculturally important phenomena. Analysis of the mechanisms underlying ethylene biosynthesis and signalling have resulted in the elucidation of multistep mechanisms which at first glance appear simple, but in fact represent several levels of control to tightly regulate the level of production and response. Ethylene biosynthesis represents a two-step process that is regulated at both the transcriptional and post-translational levels, thus enabling plants to control the amount of ethylene produced with regard to promotion of responses such as climacteric flower senescence and fruit ripening. Ethylene production subsequently results in activation of the ethylene response, as ethylene accumulation will trigger the ethylene signalling pathway to activate ethylene-dependent transcription for promotion of the response and for resetting the pathway. A more detailed knowledge of the mechanisms underlying biosynthesis and the ethylene response will ultimately enable new approaches to be developed for control of the initiation and progression of ethylene-dependent developmental processes, many of which are of horticultural significance.

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The Fundamentals of the Clinical Fellowship Experience

Perspectives of the ASHA Special Interest Groups ◽

10.1044/persp1.sig11.81 ◽

2016 ◽

Vol 1 (11) ◽

pp. 81-85

Author(s):

Melanie Hudson

Keyword(s):

Growth And Development ◽

Transition Period ◽

Clinical Skills ◽

Practical Experience ◽

Professional Experience ◽

New Graduate ◽

Independent Practitioner

The Clinical Fellowship Experience is described by the American Speech-Hearing-Language Association (ASHA) as the transition period from constant supervision to independent practitioner. It is typically the first paid professional experience for the new graduate, and may be in a setting with which the new clinician has little or even no significant practical experience. The mentor of a clinical fellow (CF) plays an important role in supporting the growth and development of this new professional in areas that extend beyond application of clinical skills and knowledge. This article discusses how the mentor may provide this support within a framework that facilitates the path to clinical independence.

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