The Nematodes That Cause Anisakiasis1,2

Anisakine nematodes responsible for human anisakiasis have been recognized in fish hosts for over a decade. They are larval stages, relatively simple in form, and lack many morphological features used for identification of the adults (e.g., cephalic structures, spicules, etc.). However, these immature helminths can be sorted into larval types on the basis of the anterior digestive tract formation and the position of the excretory pore. Problems in identfying larvae, even as to type, are often encountered in tissue sections that may not show those anterior regions containing features of the digestive system which are diagnostic for type sorting. Hence, it is necessary to reconsider the diagnostic value of lateral chords, muscle cells, etc., that are visible in all cross-sections. Fish which are eaten by the human consumer also contain larval stages of other roundworms (nematodes) than those responsible for human anisakiasis, as well as numerous species of adult nematodes.

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Formation of the gut in the first two naupliar stages of Acartia clausi and Hemidiaptomus roubaui (Copepoda, Calanoida): comparative structural and ultrastructural aspects

Canadian Journal of Zoology ◽

10.1139/z01-219 ◽

2002 ◽

Vol 80 (2) ◽

pp. 232-244 ◽

Cited By ~ 6

Author(s):

A Baud ◽

R -M Barthélémy ◽

S Nival ◽

M Brunet

Keyword(s):

Epithelial Cells ◽

Digestive Tract ◽

Digestive System ◽

Larval Stages ◽

Acartia Clausi ◽

The Future ◽

Endodermal Cells ◽

Structure And Ultrastructure

In this study, the structure and ultrastructure of the digestive system are compared in the early larval stages (nauplii I and II) of two copepod calanoid species, Acartia clausi Giesbrecht, 1889 and Hemidiaptomus roubaui Richard, 1888. The nauplii I of both species have no functional digestive tract, which is represented initially only by a blind esophageal slit and yolky endodermal cells, which fill the most part of the naupliar body, whereas at the nauplius II stage the differentiated digestive tract becomes functional. The resorption cavity corresponding to the future midgut is progressively formed in the endodermal mass during the premolt phase; it is surrounded by differentiating epithelial cells. In the ecdysial phase the foregut has associated labral glands, the midgut young R-, B-, and R'-cells of epithelium, and there is a short open hindgut.

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Entangling the Enemy: Ecological, Systematic and Medical Implications of Dermestid Beetle Hastisetae

Insects ◽

10.3390/insects12050436 ◽

2021 ◽

Vol 12 (5) ◽

pp. 436

Author(s):

Enrico Ruzzier ◽

Marcin Kadej ◽

Andrea Di Giulio ◽

Andrea Battisti

Keyword(s):

Defensive Behavior ◽

Digestive System ◽

Living Environment ◽

Morphological Features ◽

Allergic Reactions ◽

Stored Products ◽

Genus Level ◽

Basic Concepts ◽

Source Of Information ◽

Fine Morphology

Hastisetae are modified setae typical of Dermestidae Megatominae and are a primary defensive tool of both larvae and pupae against invertebrates and possibly vertebrates. Given their unique morphological features, hastisetae have recently been suggested as an additional character useful for larvae identification and possible source of information to clarify the systematics of Megatominae. Hastisetae are also recognized as important contaminants of stored products, work and living environment; in particular, the exposure to hastisetae seems to cause allergic reactions and the insurgence of skin rashes, asthma, conjunctivitis, and digestive system inflammation in humans. Starting from these basic concepts, the present paper provides a detailed description of the hastisetae of some Megatominae. Fine morphology of external and internal microstructures of the hastisetae is shown and compared at the genus level. The insertion on integument, the pedicel, the shaft, and the apical head are illustrated in detail, and the first observations of active defensive behavior based on hastisetae are recorded and presented. Possible implications to the systematics of skin beetles are proposed based on the results of the study.

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The Development and Growth of Ciona

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400013825 ◽

1947 ◽

Vol 26 (4) ◽

pp. 616-625 ◽

Cited By ~ 58

Author(s):

N. J. Berrill

Keyword(s):

Nervous System ◽

Digestive System ◽

Ciona Intestinalis ◽

Growth Cycle ◽

General Interest ◽

Botryllus Schlosseri ◽

Developmental Studies ◽

Larval Stages ◽

Artificial Fertilization ◽

Sexually Mature

Ciona intestinalis (L.) is probably the most cosmopolitan species of ascidians and has long been of general interest. The adult morphology has been well described in monographic form by Roule (1884), the physiology of the heart and circulation by Heine (1902), Enriques (1904) and Wolf (1932), of the nervous system by Magnus (1902), Hecht (1918, 1926), Cate (1928), Haffner (1933), and Bacq & Florkin (1935), and of the digestive system by Yonge (1925). Developmental studies include that of the early embryology by Conklin (1905), problems of fertilization by Morgan (1945) and Damas (1899,1900). In no work, however, has there been a presentation of the entire Ciona organism from the tadpole stage through the critical post-larval stages to the young cionid ascidian. The present account portrays this period of development, together with a discussion of some significant but relatively obscure aspects of adult structure.Eggs and theRearing ofCiona intestinalisWhile ascidians in general are difficult to rear to maturity under laboratory conditions, Ciona is relatively easy, and together with Botryllus schlosseri (Pallas) and Diplosoma gelatinosum (M.-Edw.) is liable to appear more or less spontaneously in large aquaria into which tadpoles may have been brought. Artificial fertilization is readily accomplished, and at almost any time of the year, since Ciona is sexually mature above a certain size and reproduction is seasonal only to the extent of the rhythm of the growth cycle. Normally eggs are set free spontaneously at dawn, although individuals kept in the laboratory may accumulate eggs and the oviduct become swollen.

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Morphohistology of the Digestive Tract of the Damsel FishStegastes fuscus(Osteichthyes: Pomacentridae)

The Scientific World JOURNAL ◽

10.1100/2012/787316 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 16

Author(s):

Bhaskara Canan ◽

Wallace Silva do Nascimento ◽

Naisandra Bezerra da Silva ◽

Sathyabama Chellappa

Keyword(s):

Digestive Tract ◽

Transition Region ◽

Digestive System ◽

Feeding Habits ◽

Northeastern Brazil ◽

Muscular Layer ◽

Pyloric Caeca ◽

Anterior Intestine ◽

The Mean ◽

Tidal Pools

This study investigated the morphohistology of the digestive tract and the mean intestinal coefficient of the damsel fishStegastes fuscuscaptured from the tidal pools of Northeastern Brazil. The wall of the digestive tract ofS. fuscusis composed of the tunica mucosa, tunica muscularis, and tunica serosa. The esophagus is short with sphincter and thick distensible wall with longitudinally folded mucosa. Mucous glands are predominant, and the muscular layer of the esophagus presented striated fibers all along its extension. The transition region close to the stomach shows plain and striated muscular fibers. Between the stomach and intestine, there are three pyloric caeca. The intestine is long and thin with four folds around the stomach. The anterior intestine presents folds similar to those of pyloric caeca. The estimated mean intestinal coefficient and characteristics of the digestive system ofS. fuscuspresent morphological adequacy for both herbivorous and omnivorous feeding habits.

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The enteric nervous system of echinoderms: unexpected complexity revealed by neurochemical analysis

Journal of Experimental Biology ◽

10.1242/jeb.204.5.865 ◽

2001 ◽

Vol 204 (5) ◽

pp. 865-873

Author(s):

J.E. Garcia-Arraras ◽

M. Rojas-Soto ◽

L.B. Jimenez ◽

L. Diaz-Miranda

Keyword(s):

Nervous System ◽

Enteric Nervous System ◽

Digestive Tract ◽

Radial Nerve ◽

Digestive System ◽

Nerve Ring ◽

Point Of View ◽

Distinct Component ◽

Future Studies ◽

Neurochemical Analysis

Echinoderms are one of the most important groups of metazoans from the point of view of evolution, ecology and abundance. Nevertheless, their nervous system has been little studied. Particularly unexplored have been the components of the nervous system that lie outside the ectoneural and hyponeural divisions of the main nerve ring and radial nerve cords. We have gathered information on the nervous components of the digestive tract of echinoderms and demonstrate an unexpected level of complexity in terms of neurons, nerve plexi, their location and neurochemistry. The nervous elements within the digestive system consist of a distinct component of the echinoderm nervous system, termed the enteric nervous system. However, the association between the enteric nervous system and the ectoneural and hyponeural components of the nervous system is not well established. Our findings also emphasize the importance of the large lacunae in the neurobiology of echinoderms, a feature that should be addressed in future studies.

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Occurrence of Tetracampos ciliotheca and Proteocephalus glanduligerus in Clarias gariepinus (Burchell, 1822) collected from the Vaal Dam, South Africa

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v80i1.522 ◽

2013 ◽

Vol 80 (1) ◽

Cited By ~ 3

Author(s):

Grace Madanire-Moyo ◽

Annemariè Avenant-Oldewage

Keyword(s):

South Africa ◽

Digestive Tract ◽

Standard Length ◽

Feeding Habits ◽

Clarias Gariepinus ◽

Male And Female ◽

Mean Intensity ◽

Gill Nets ◽

Larval Stages ◽

Vaal Dam

Cestodes are parasitic flatworms that live in the digestive tract of vertebrates as adults and often in the liver, muscle, haemocoel, mesentery and brain of various animals as larval stages. To identify the cestodes infecting Clarias gariepinus Burchell, 1822 (sharptooth catfish) in the Vaal Dam, a total of 45 host specimens were collected with the aid of gill nets between October 2011, January and April 2012. The fish were sacrificed and examined for cestode parasites. Two adult cestodes, Tetracampos ciliotheca Wedl, 1861 (prevalence 86.7%, mean intensity = 15, n = 45) and Proteocephalus glanduligerus (Janicki, 1928) (prevalence 51.1%, mean intensity = 5, n = 45) were found in the intestines of the catfish. Both T. ciliotheca and P. glanduligerus are new locality records. There were statistically insignificant differences in the infection of the male and female C. gariepinu. Fish with standard length ranging from 40 cm – 54 cm (≥ 3 years) had the highest prevalence and mean intensity while those ranging from 10 cm – 24 cm (< 1 year) had the lowest prevalence and mean intensity for both cestodes. The study highlights the importance of changing feeding habits of C. gariepinus with age on the prevalence and mean intensity of the two gastrointestinal cestode parasites.

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ABO histo-blood groups and Rh systems in relation to malignant tumors of the digestive tract in Bosnia and Herzegovina

Archives of Biological Sciences ◽

10.2298/abs0804593j ◽

2008 ◽

Vol 60 (4) ◽

pp. 593-599 ◽

Cited By ~ 3

Author(s):

Snezana Jovanovic-Cupic ◽

Gorana Stamenkovic ◽

Jelena Blagojevic ◽

N. Vanis ◽

B. Stanojevic ◽

...

Keyword(s):

Gastric Cancer ◽

Digestive Tract ◽

Digestive System ◽

Malignant Tumors ◽

Blood Groups ◽

Liver Carcinoma ◽

Abo Blood Groups ◽

Rhesus Factor ◽

Clinical Center ◽

Group B

The distribution of ABO blood groups and the Rhesus factor was analyzed in 279 patients who suffered from malignant tumors of the digestive system. Patients were registered retrospectively in the Gastroenterohepatology Clinic, Clinical Center, University of Sarajevo over a discontinuous period of 88 months. From the results obtained, it was concluded that: (a) men became ill from gastric cancer significantly more frequently than women; (b) the frequency of liver carcinoma was three times higher than the global frequency and the frequency neighboring ethnic groups; and (c) patients with blood group B and patients with RhD(-) exhibited a significantly higher proportion of disease.

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Morphological Features Of The Immune Structures Of The Thin Intestine Of Laboratory Animals With Various Characters Of Nutrition

The American Journal of Medical Sciences and Pharmaceutical Research ◽

10.37547/tajmspr/volume02issue09-15 ◽

2020 ◽

Vol 2 (09) ◽

pp. 72-74

Author(s):

Khusanov Erkin ◽

Ortikbaeva Nilufar ◽

Korzhavov Sherali

Keyword(s):

Small Intestine ◽

Digestive Tract ◽

Structural Organization ◽

Morphological Changes ◽

Comparative Morphology ◽

Morphological Features ◽

The Body ◽

Laboratory Animals ◽

Chemical Processing ◽

Digestive Tube

The nutritional nature of mammals, which has developed during a long evolution, leads to adaptive - morphological changes in their digestive tract and its immune structures, although the general laws of their structural organization are identical. The literature has data on the study of the immune structures of the small intestine under normal conditions and under the influence of certain factors. In the structure of immune structures there are numerous parallelisms, however, in each class of vertebrates, complication of this organization is achieved independently. The small intestine is an important section of the digestive tube, where the final chemical processing of the chyme and the absorption of nutrients into the body take place. However, the comparative morphology of the immune structures of the small intestine in mammals with different nutrition patterns remains poorly understood.

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Contribution to the parasites and associated pathology of wild Serranidae from the Aegean Sea

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.16058 ◽

2018 ◽

Vol 68 (4) ◽

pp. 599

Author(s):

V. BAKOPOULOS ◽

A. NIKOLAIDIS ◽

M. KOLYGAS ◽

F. ATHANASSOPOULOU

Keyword(s):

Digestive Tract ◽

Microscopic Observation ◽

Pathogenic Bacteria ◽

Scientific Information ◽

Aegean Sea ◽

Pathological Findings ◽

Tissue Sections

Parasites and associated pathology of wild caught Serranidae in the Aegean Sea were investigated in order to contribute to the scientific information regarding pathological findings of these fish. Various lesions and parasitic organisms, such as Digenean parasites, cysts and metacercaria, Cestode cysts and a nematode, were observed in the gills / pseudobranchs, liver, the wall of the digestive tract, the mesentery and the ovaries. None of these lesions were considered to be of pathogenic bacteria nature based on microscopic observation of stained tissue sections of affected organs. The most frequently observed parasitism among all the species studied was from Digenean parasites (11 out of 16 specimens examined) compared to infection by both cestodes and nematodes (3 out of 16 specimens examined). Heavier infestation was observed for the unidentified Digenean cysts that were found in the mesentery of one specimen (120 counts), followed by Didymozoan parasites (average 19.25 counts per specimen).

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