Observations on the food and the gut pigment of the Polyopisthocotylea (Trematoda: Monogenea)

Llewellyn, J.

doi:10.1017/s0031182000019107

Cited by 64 publications

(40 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such an adhesive attitude is obviously well adapted to meet what appear to be the major ecological problems facing these parasites, namely those of clinging to the host in the face of a current, and of feeding, from the highly vascular secondary lamellae, on the blood that forms the main part of their diet (Llewellyn, 1954). The particular forms of adhesive attitude have been found to vary considerably.…”

Section: Discussionmentioning

confidence: 99%

The host-specificity, micro-ecology, adhesive attitudes, and comparative morphology of some trematode gill parasites

Llewellyn

1956

J. Mar. Biol. Ass.

Self Cite

113

View full text Add to dashboard Cite

In recent years there have been several accounts of the occurrence of diclidophoroidean trematodes parasitic on the gills of fishes, e.g. Price (1943), Sproston (1946), Dawes (1947), Brinkmann (1952), and Chauhan (1953), and these accounts have included descriptions of the morphology of the parasites. The distribution records have revealed a generally high degree of host specificity and, in some species, a preference even for certain gill arches of the particular hosts, while the morphological descriptions have shown that there is a considerable variation in the form of the parasites, extending to various degrees of deviation from bilateral symmetry (PI. I, figs. 1–11). These morpho-logical variations are present in spite of the fact that the different parasites occupy such broadly similar habitats in the gill chambers of their respective hosts. But, as far as I am aware, this is the first attempt to investigate the distribution and morphology of the parasites in relation to their micro-habitats.

show abstract

Section: Discussionmentioning

confidence: 99%

The host-specificity, micro-ecology, adhesive attitudes, and comparative morphology of some trematode gill parasites

Llewellyn

1956

J. Mar. Biol. Ass.

Self Cite

113

View full text Add to dashboard Cite

show abstract

“…Ci!l filaments with attached parasites from freshly preserved material were embedded in wax, sectioned and stained with haematoxylin and eosin (H&E). To determine if gut pigment in N. vanabilis was derived from a blood diet, the rate of bleaching of the pigment in hydrogen peroxide was examined (Llewellyn 1954). N. variabilis were cut in half and placed in 30 mg ml-' (10 volume) hydrogen peroxide for up to 12 h. Control tissues also placed in hydrogen peroxide at the same time were the gut contents of the sanguinivorous copepod Lernanthropus atrox, and pieces of fin and kidney with melanin deposits.…”

Section: Methodsmentioning

confidence: 99%

Extent of gill pathology in the toadfish Tetractenos hamiltoni caused by Naobranchia variabilis (Copepoda:Naobranchiidae)

Roubal¹

1999

Dis. Aquat. Org.

View full text Add to dashboard Cite

Sanguinivorous Naobranchia variabilis prefer the first gill arch, external hemibranch and anterior end of the gill arch. The smallest N. variabilis observed attached to fish by a thin filament which connects fused tips of second maxillae to a 'plug' inserted into the gill tissue. Second maxillae enlarge to encircle and increasingly compress the gill filament, which results in a thin layer of epithelium and connective tissue overlying the cartilaginous supporting bar. Early juveniles cause little tissue proliferation, but the extent of proliferated epithelia] and connective tissue (PR) adjacent to the maxillae increases from late juveniles to subadult and adult copepods. Most vanation in length of gill filament damage (PL, proliferated and compressed tissue) among age classes is explained by maxilla length (ML, length of compressed gill filament); adult trunk width (TRW) explains an extra, small amount of variation, but not trunk length (TRL) or total fish length (TL). Most variation in ML is explained by TRW of adults, subadults and late juveniles, and TRL of edrly juveniles. PR is explained by TRW for adults, but by ML for other ages. These patterns are due to elongation of the juvenile trunk during growth and lateral expansion of adult egg pouches during maturation. Up to 38 N. variabilis, average (avg.) = 9.3, infected individual Tetractenos hamiltoni and damaged up to 3.4 % (avg. 0.72%) of total filament length and 8.6% (avg. 2.1 %) of gill filaments per fish.

show abstract

“…The chemical nature of the pigments observed in the endocytosed vesicles was initially tested according to its solubility in picric acid in ethyl alcohol (Llewellyn 1954). Knowing that both formolic (formaldehyde) and hematin (hemoglobin) pigments are solved by picric acid and that formolic pigments do not react in the presence of Prussian blue (Perls), Turnbull blue, ferricyanide and ferrocyanide, contrary to what happen to hematin pigments (Lillie & Fullmer 1976), these tests were applied in samples fixed either in 70% ethanol and buffered formalin.…”

Section: Discussionmentioning

confidence: 99%

“…This can be explained by fish handling. The monogeneans were collected some hours after fish capture and according to Llewellyn (1954) erythrocytes can only be observed in their gut when fish are examined in less than one hour after capture, because a rapid haemolysis followed by phagocytosis normally occur. However, it cannot be excluded that erythrocytes are lysed during the feeding process.…”

Section: Discussionmentioning

confidence: 99%

The Ultrastructure of the Gastrodermis and the Nutrition of the Gill Parasitic Atriaster heterodus Lebedev and Paruchin, 1969 (Platyhelminthes: Monogenea)

Santos

Souto-Padrón

Lanfredi

1998

Mem. Inst. Oswaldo Cruz

View full text Add to dashboard Cite

The gastrodermis of Atriaster heterodus Lebedev & Paruchin, 1969 (Polyopisthocotylea), a gill parasite from Diplodus argenteus (Valenciennes, 1830) The functional morphology of the digestive system has been studied for different Monogenea (Smyth & Halton 1983, Bogitsh 1993 and the feeding in polyopisthocotyleans and monopisthocotyleans is generally distinct with the former ingesting blood (Llewelyn 1954, Halton 1982 and the latter, mucus and epithelial cells. However, blood pigments were observed in a few monopisthocotyleans (Uspenskaya 1962, Kearn 1963, Fournier 1978, Buchmann et al. 1987) while Allen and Tinsley (1989) demonstrated blood and epithelial cells at the same time in the gut lumen of a polyopisthocotylean species.Atriaster heterodus Lebedev & Paruchin, 1969 (Polyopisthocotylea) was recently reported from Rio de Janeiro coast (Santos et al. 1996). Surface topography and ultrastructural aspects of the spermatogenesis of this species have been described by Santos et al. (1997). The ultrastructure of the gastrodermis and the nutrition of this species are described herein. This paper represents the first ultrastructural study of gut caeca and nutrition of a marine monogenean from Brazil. MATERIALS AND METHODSParasites -Sixty five specimens of A. heterodus were obtained from the gills of 25 Diplodus argenteus (Valenciennes, 1830) Sparidae, collected in Copacabana beach, Rio de Janeiro, Brazil.Histochemistry -Monogeneans and gill filaments were fixed in 5% buffered formalin or 70% ethanol. Samples were embedded in paraffin and cut in 5 mM sections which were deparaffinized with xylene and prior to staining, hydrated in decreasing concentrations of ethanol to water. Histochemical reactions are indicated with the references and color of positive reactions as follows. Lilly and Fullmer (1976) were tested Perls (+=blue-green), Okajima (+=or-ange-red) and Dunn-Thompson (+= emerald green). The picric alcohol solubility test (Llewelyn 1954) was tested for hematin (+=solve).Ultrastructure -For ultrastructural studies, parasites were fixed for 2 hr at 4°C in a solution containing 4% paraformaldehyde, 2.5% glutaraldehyde and 0.3M sucrose in 0.1M cacodylate buffer in sea water, pH 7.2. After being washed in the same solution, they were post-fixed for 1 hr in dark conditions in a solution containing 1% OsO 4 , 0.8% potassium ferricyanide, and 5mM CaCl 2 in

show abstract

Observations on the food and the gut pigment of the Polyopisthocotylea (Trematoda: Monogenea)

Cited by 64 publications

References 7 publications

The host-specificity, micro-ecology, adhesive attitudes, and comparative morphology of some trematode gill parasites

The host-specificity, micro-ecology, adhesive attitudes, and comparative morphology of some trematode gill parasites

Extent of gill pathology in the toadfish Tetractenos hamiltoni caused by Naobranchia variabilis (Copepoda:Naobranchiidae)

The Ultrastructure of the Gastrodermis and the Nutrition of the Gill Parasitic Atriaster heterodus Lebedev and Paruchin, 1969 (Platyhelminthes: Monogenea)

Contact Info

Product

Resources

About