Cecum Intestine Research Articles

Symbiotic relationship of thiothrix spp. with An echinoderm

Immunoassay procedures were used to investigate the symbiotic relationship of Thiothrix spp. in the intestinal cecum of the spatangoid species Echinocardium cordatum. Thiothrix spp. were identified in nodule samples from E. cordatum digestive tubes based on microscopic examination, enzyme-linked immunosorbent assay, and indirect immunofluorescence. Thiothrix spp. protein made up as much as 84% of the total protein content of the nodules. This is the first identification of Thiothrix spp. internally symbiotic with marine invertebrates.

Gastric Na +K +ATPase activity and intestinal urea hydrolysis of the common vampire bat, Desmodus rotundus

The blood diet of the vampire bat represents an extraordinarily high ratio of protein to other nutrients and the highest water consumption per body weight of any other mammal. This bat has a unique gastrointestinal morphology that is characterized by a reduced small intestine, absence of a large intestine and intestinal cecum and the presence of a water-absorptive gastric fundus. The present study demonstrates that the gastric fundus has a greater Na +K +ATPase activity for active ion transport compared with other equally sized mammals. This activity is believed to be necessary to establish a gradient favoring water absorption across what would otherwise be an osmotic disequilibrium. The absence of a large intestine and intestinal cecum may reflect a reduced urea hydrolysis by the vampire bat. The present study demonstrated that the vampire bat does not hydrolyze urea as does an equally sized non-sanguinivorous mammal. These data suggest that the blood diet and the relocation of water-absorptive tissue from the lower intestinal tract to the stomach is associated with an active ion transport mechanism in the gastric tissue and a reduced capacity for ureolytic microbes to hydrolyze urea in the intestine. Both processes are specializations for a diet high in protein and water.

In VitroMethylation of Inorganic Arsenic in Mouse Intestinal Cecum

The capacity of mouse intestinal cecal microflora to methylate inorganic arsenicals (iAs) was examinedin vitrounder conditions of restricted bacterial growth. Cecal contents incubated under anaerobic conditions at 37°C for 21 hr methylated up to 40% of either 0.1 μmarsenite (iAsIII) or 0.1 μmarsenate (iAsV). Methylarsenic (MAs) was the predominant metabolite; however, about 3% of either substrate was converted to dimethylarsenic (DMAs). Over the first 6 hr, the rate of methylation was several times greater for iAsIIIthan for iAsV. There was a 3-hr delay in the production of methylated metabolites from iAsV, suggesting that reduction of iAsVto iAsIIIbefore methylation could be rate limiting. Over the concentration range of 0.1 to 10 μmof iAsIIIor iAsV, there was an approximately linear increase in the production of MAs and DMAs. There was evidence of saturation or inhibition of methylation at 100 μmof either substrate. Substrate concentration had little effect on MAs/DMAs ratio. Incubation of cecal contents at 0°C abolished methylation of either arsenical. Under aerobic or anaerobic conditions, cecal tissue homogenates produced little MAs or DMAs from either arsenical. Addition of potential methyl group donors,l-methionine and methylcobalamin, into cecal contents significantly increased the rate of methylation, especially for iAsV. Addition of glutathione, but notl-cysteine, had a similar effect. Selenite, a recognized inhibitor of iAs methylation in mammalian tissues, inhibited methylation of either substrate by cecal contents. These data suggest that cecal microflora are a high capacity methylation system that might contribute significantly to methylation of iAs in intact animals.

Description of a New Species of Maritrema (Digenea: Microphallidae) from Mar Chiquita Coastal Lagoon (Buenos Aires, Argentina) with Notes on Its Life Cycle

Adults of Maritrema bonaerensis n. sp. (Digenea:Microphallidae) were collected from the intestine of the gulls Larus maculipennis and Larus atlanticus from Mar Chiquita coastal lagoon, Buenos Aires province, Argentina. The new species differs from M. pulcherrima Travassos, 1928 in having smaller sucker ratio, longer intestinal ceca, ovary not lobed, and larger eggs, and from Maritrema prosthometra Deblock and Heard, 1969 it differs in having larger suckers, smaller vitelline follicles, and in the absence of pars prostatica. It differs from Maritrema acadiae (Swales, 1933) in having larger body and pharynx and longer cirrus. It differs from Maritrema paracadiae Ching, 1974 in the larger pharynx, longer cirrus, and in the absence of prominent prostatic cells. From Maritrema majestova Ke, 1976, it differs in having a larger body, smaller eggs, and a long and protusible cirrus. Finally, M. bonaerensis differs from Maritrema chiricae Deblock, 1975 in the larger body, longer cirrus, and in the morphology of the seminal vesicle. Sporocysts and metacercarial stages isolated from the snail Heleobia australis australis and from the crabs Cyrtograpsus angulatus and Chasmagnatus granulata, respectively, suggest that those invertebrates could act as intermediate host in the life cycle of the new species in the lagoon. This assumption is supported by evidence derived from natural and experimental infections, from studies on biology of the actual and presumed hosts, as well as from previous reports on life cycles of species of Maritrema with similar transmission patterns.

A Reexamination of Proposed Morphology-Based Synapomorphies for the Families of Dasyuromorphia (Marsupialia). I. Dasyuridae

The validity of eight morphological features previously advanced as synapomorphic for Dasyuridae is investigated in the light of new fossil and molecular data. Results indicate that one of these features (alisphenoid–periotic enclosure of the foramen ovale) is common to outgroups for Dasyuromorphia. Another feature (loss of intestinal cecum) is a likely synapomorphy for Dasyuromorphia. Two features (development of a hypoconulid notch, enlargement of stylar cusp D) may represent shared–derived characters within Dasyuromorphia but not at the family level for Dasyuridae (i.e., probably unite Dasyuridae–Thylacinidae). Another two features (loss of posterolateral palatine foramina, reduction of P3) are also apomorphic within Dasyuromorphia but unite specialized clades within Dasyuridae. Only two previously treated features are probable synapomorphies for the family (enlargement of the alisphenoid tympanic wing and development of a distinct periotic hypotympanic sinus). An additional feature is identified as a dasyurid synapomorphy (presence of a distinct tubal foramen). Of all putative synapomorphies proposed to date, only the presence of a periotic hypotympanic sinus and tubal foramen are unique for Dasyuridae among dasyuromorphians. Results suggest considerable homoplasy for basicranial features within Dasyuromorphia. Independent acquisition for alisphenoid enclosure of the foramen ovale, development of secondary foramina ovale and loss of posterolateral palatal foramina has occurred in derived thylacinid and dasyurid clades. Convergence is also indicated for hypertrophy of the alisphenoid tympanic wing shown for dasyurids and myrmecobiids, and the development of a squamosal epitympanic sinus in Thylacinidae, Dasyuridae, and Myrmecobiidae. The finding of plesiomorphy for alisphenoid–periotic enclosure of the foramen ovale within Dasyuromorphia undermines the strongest morphology-based synapomorphy uniting a monophyletic Dasyuridae–Myrmecobiidae. Phylogenetic placement for some plesiomorphic fossil dasyuromorphians, known only from dental material, within Dasyuridae is currently untenable, with no dental synapomorphies uniting the family. The value of identifying morphoclines within clades known from robust phylogenetic data for consideration in character analysis is stressed, as is the importance of form–function and ontogenetic data.

A new species of Megalophallus (Digenea: Microphallidae) from the clapper rail, other birds, and the littoral isopod Ligia baudiniana

Megalophallus reamesi n.sp. infected the clapper rail, ruddy turnstone, black-bellied plover, and the isopod Ligia baudiniana. This precociously developed digenean occurred in the mid-Florida Keys, Florida, and in Pine Cay, Turks and Caicos, British West Indies, but not in numerous other examined localities from New York to Texas. It is most similar in body size (1.0–1.6 vs 1.0–1.1 mm) and structure of its copulatory organ to M. diodontis Siddiqi and Cable, 1960, but its copulatory organ has 23–39 micropapillae rather than 12–19, the species has rudimentary intestinal ceca rather than short fully developed ones, and an isopod rather than a portunid crab serves as the second intermediate host. The encysted metacercaria, occurring in the hemocoel of the isopod, was typically encapsulated with host connective tissue incorporating several host chromatophores.

Recovery of Pseudoterranova decipiens (Anisakidae) larvae from codfish of the Antarctic Ocean.

Anisakid larvae were found from the liver and stomach of the codfish (Notothenia neglecta) caught from the Antarctic Ocean, South Pole, where the Polar Research Center of The Korea Ocean Research and Development Institute is operating. Through observations by scanning electron (SEM) and light microscopy (LM), they were identified as the third stage larvae of Pseudoterranova decipiens, a potential agent of human codworm anisakiasis. They measured 25.0-28.5 mm in length, and 0.6-0.8 mm in width. The SEM revealed a prominent boring tooth, three lips, and excretory pore at the anterior end, and a small but prominent mucron at the posterior end. From whole mounts and cross sections of the larvae the ventriculus, intestinal cecum and a Renette cell were found characteristically at the same plane. Raw eating of the codfish caught from the Antarctic Ocean near the South Pole should be avoided so as to prevent human codworm anisakiasis in this area.

Studies on cercariae from the Kuwait Bay. VI. Description and surface topography of Cercaria kuwaitae VI sp. n. (Trematoda: Haplosplanchnidae).

A new haplosphlanchnid cercaria, Cercaria kuwaitae VI sp. n., was found in the prosobranch snail Cerithidea cingulata in the Kuwait Bay. Details are presented on the morphology and behavior of the cercaria and the encystment process. The new cercaria is a biocellate, distome, with a prominent single sac-like intestinal cecum extending well posterior to the ventral sucker and develops in simple sporocysts. It differ from known haplosplanchnid cercariae in the absence of finger-like processes on the tail, and the presence of V-shaped excretory vesicle extending beyond ventral sucker and the presence of cervical glands. The surface topography of the cercaria and its sporocyst is examined by scanning electron microscopy. This is the first haplosplanchnid cercaria to be described from a Cerithidea species.

The Development of a Hemogregarine of Lycodes raridens from Alaska in Its Definitive Leech Host

Piscicolid leeches from the Bering Sea that had been removed from Lycodes raridens in 1977 were examined histologically. Developmental stages of a haemogregarine blood parasite of fish were found in the intestinal ceca and in salivary tissues. The developmental sequence, including gametogenesis and sporogony followed by intestinal merogonic development and anteriad migration, was the same as is known for Haemogregarina (sensu lato) myoxocephali of Atlantic sculpins. Merozoites with perinuclear crystalloid inclusions were found in the dorsal blood vessel, interstitially between the blood vessel and salivary cells and within both the somata and ductules of salivary cells. This confirms the importance of rhynchobdellid leech circulatory anatomy in facilitating the transmission of apicomplexan parasites. The lack of distinguishing characteristics precludes assigning a specific name to this parasite and may be indicative of frustrations that will be encountered in future revisions of the systematics of the genus Haemogregarina.

EXPERIMENTAL INFECTION OF DOMESTIC DUCKS AND RODENTS BY NOTOCOTYLUS ATTENUATUS (TREMATODA: NOTOCOTYLIDAE)

In order to study transmission patterns of Notocotylus attenuatus five 3-wk-old domestic ducks, five 8-wk-old rats and ten 4-wk-old mice were infected with the parasite. All ducks became infected and all flukes were recovered from the intestinal ceca. Worms moved down the length of the cecum during development and as the parasites grew they changed their method of attachment. Flukes became gravid by day 16 post-infection, after which growth ceased. Egg filaments appear to play a role in the formation and movement of worm egg clusters from the distal portion of the cecum to the lumen of small intestine. Rodents also became infected with the parasite producing granulomatous nodular lesions in the lower small intestine but all flukes in the granulomata were dead. It is unlikely that transmission of this trematode can depend on mice and rats.

Two new species of umagillid flatworms from the 20-rayed antarctic crinoid Promachocrinus kerguelensis

Two new endosymbiotic turbellarians from the 20-rayed crinoid Promachocrinus kerguelensis are described from specimens collected off the western coast of the Antarctic Peninsula. Desmote antarcticus sp.n. differs from previously described members of the genus in the shape of the penis stylet, orientation of the terminal branches of the ovaries, and connections of the genital ducts to the exterior. Parafallacohospes bransfieldensis gen. et sp.n. is distinctive among known umagillids in having a pair of broad lobes projecting from each side of the body. The anatomy of the reproductive system is similar to that of Fallacohospes inchoatus Kozloff except that P. bransfieldensis lacks a secondary uterus. In addition, P. bransfieldensis has a functional digestive tract with small intestinal ceca, whereas F. inchoatus, the only species in the genus Fallacohospes, lacks a digestive tract. In this respect, Parafallacohospes appears to be intermediate between Desmote, which has large intestinal ceca, and Fallacohospes. Both new species belong to the subfamily Bicladinae, which includes all other crinoid-inhabiting umagillid flatworms.

Growth and development of Pygidiopsis summa in rats and mice with a supplementary note on its morphological characters.

The growth and development of Pygidiopsis summa were studied in experimental rats and mice, and a special reference was given to its morphological characters differed from the type species, P. genata. The metacercariae were obtained from young mullets (Mugil sp.), and total 21 rats and mice infected each with 1,000 metacercariae. Worms of various ages of infection, from 3 to 28 days, were subjected to a microscopic observation. The worms grew rapidly and remarkably in size up to 10 days of infection, to become 0.53-0.82 mm long and 0.31-0.39 mm wide, but nearly stopped the growth thereafter. Their genital organs developed more rapidly and fully matured within 3-5 days. At 3 days several eggs were found in uterus. The presence of two groups of small spines, 5-6 on the right and 7-9 on the left side of the genital apparatus, was a new finding in this study and considered a distinct character of P. summa. The morphology of ventral sucker and intestinal ceca was also different from P. genata. This study confirms the validity of the species, P. summa.

Sterols of Echinostoma revolutum (Trematoda) Adults

diate hosts (Hopkins, 1954, Journal of Parasitology 40: 29-31; Wardle, 1980, Bulletin of Marine Science 30: 737-743). Adult worms develop in hindguts of marine fish, Archosargus probatocephalus (Walbaum), which feed on hooked mussels (Wardle, 1980, loc. cit.). Although metacercariae are well developed in I. recurvum, progenesis has not been reported for P. maculatus from warmer waters of the southern United States. The present study describes the interactions between hooked mussels and metacercariae. During May 1984 hooked mussels were collected from an oyster reef in Calcasieu Lake, Louisiana (average salinity 17.2 ppt), taken to the laboratory, and their soft-parts examined with a stereomicroscope. Trematode specimens were removed and studied live. Small pieces of host organs containing metacercariae were fixed in Bouin's solution, prepared by routine histological procedures, serially sectioned at 7 gtm and stained with hematoxylin and eosin. Yellow marked sites of metacercariae in the mantle, gonad and digestive gland of the host. When larvae were removed and examined, their intestinal ceca contained host cells that were regurgitated under coverslip pressure. Histological sections showed larvae encapsulated within granulomas containing infiltrates of host leukocytes (Fig. 1). Although many were ingested by larvae, leukocytes were responsible for the yellow pustules and were so numerous as to form large clumps after fixation (Fig. 2). Capsule walls were thin and contained a loose network of extracellular fibers (Fig. 2). Host-parasite interactions were similar to those reported by Tripp and Turner (1978. In Comparative pathobiology, Vol. IV, L. A. Bulla and T. C. Cheng (eds.). Plenum Press, New York, pp. 73-84) for M. edulis infected with adult P. maculatus. As in the present study those authors described a leukocytic response in which host cells migrated and surrounded worms only to be ingested by them. However, the response of M. edulis apparently did not involve encapsulations of parasites with concomitant infiltrations of leukocytes through thin capsule walls. This research was supported by a grant from the U.S. Department of Commerce, Office of Coastal Zone Management.

Prevalence of Setaria equina (Nematode: Onchocercidae) in Southeastern Louisiana Horses

sucker of whole worms (Figs. 1-5). Only the flammiferous tubules of the excretory system, and not the siphonal tube or excretory bladder (see Mueller, 1935, Journal of Parasitology 21: 99-103) reacted in whole worms (Figs. 1, 2) and cryostat sections. The reaction in the flammiferous tubules was more intense in 1-3 than 4-6day-old whole worms (Figs. 1-5) and cryostat sections. A slight reaction was apparent in the nervous system, mainly in the cerebral ganglia and commissure of whole worms (Fig. 2). The intestinal ceca also showed slight reactivity, although cecal contents reacted heavily in 2and 3-day-old whole worms (Figs. 2, 3). Cecal contents contained blood ingested from the chorioallantois. In summary, AlP reactivity was used to visualize various organ systems in whole L. constantiae during its development from the metacercaria to the ovigerous adult on the chick chorioallantois. This work was supported in part by funds from the Kreider Professorship to B.F. and Grant RR8006 from the General Research Support Branch, Division of Research Resources, National Institutes of Health to W.B.L.

Simple Centrifugation Method for Rapid Separation of Sporozoites from Mosquitoes

characteristic Y-shape. Whole specimens are necessary to confirm the identification. Type HA can be differentiated from the 6 thirdstage larval types belonging to the genus Terranova that have been adequately described by the relative lengths of the ventriculus and intestinal cecum. Four larval types, Type B of Koyama et al. (1969, Jap. J. Parasit. 18: 466-487) from Japan, Type I of Cannon (1977, Int. J. Parasit. 7: 233-243) from Queensland, type HB of Deardorff et al. (1982, loc. cit.) from the Hawaiian Islands, and T. secundum (as Porrocaecum s.) of Chandler (1935, Proc. U.S. Natn. Mus. 83: 123157) from Galveston Bay, Texas, have been described as possessing an intestinal cecum the same length as, or slightly longer than, the ventriculus. The 2 other larval types, Type II of Cannon (loc. cit.) and T. trichiuri (as Porrocaecum t.) of Chandler (loc. cit.) and Lent and Teixeira de Freitas (1948, Mems Inst. Oswaldo Cruz 46: 271), were described as having a cecum about twice as long as the ventriculus. Therefore, by possessing a cecum that is much shorter than the ventriculus, type HA larvae may be differentiated from these other types. We are grateful for the technical assistance of Robert A. Rychlinski in our laboratory and express our appreciation to the staff and management of Fishland Market, Ltd. and U. Okada and Co. for their cooperation during this study. This study was supported by Contract No. 22380-2295 from the Food and Drug Administration. . cit.) and T. trichiuri (as Porrocaecum t.) of

A human case infected by the larva of Terranova type A in Korea.

A human case infected with Terranova type A larva was found in Korea. The patient was a 23-year old soldier of the Korean Army and the chief complaint was acute abdominal pain. The pain was chiefly at right lower quadrant. Appendectomy was performed under the clinical impression of acute appendicitis. However, during the surgery, a nematode larva was found moving on the serosal surface of terminal ileum. The worm was 25.76mm long and 0.66mm wide, and had the intestinal cecum reaching to anterior one-third level of ventriculus and a mucron at posterior end. Therefore, it was diagnosed as Terranova type A larva. This is the first human case of Terranova type A larva infection in Korea.

Histochemical Observations on Melanin in the Intestinal Ceca of Amblosoma suwaense (Trematoda: Brachylaimidae) Metacercariae

The intestinal ceca of metacercariae of Amblosoma suwaense (Brachylaimidae) from Campeloma decisum snails in Wisconsin are filled with black pigment (Font, 1980, J. Parasitol. 66: 861-862). The purpose of this study was to demonstrate histochemically that this pigment is melanin. Amblosoma suwaense metacercariae dissected from the visceral epithelium of naturally infected C. decisum snails from Wisconsin were fixed in 10% neutral buffered formalin (NBF), frozen at -20 C, sectioned on a cryostat at 8 g/m, and stained for melanin using the Fontana method, Nile Blue, Lillie's alternate Nile Blue, and Ferro-ferricyanide (Humason, 1972, Animal tissue techniques, Freeman, San Francisco, California, 641 p.). Cryostat sections of metacercariae were also used for bleaching and solubility tests (Pearse, 1972, Histochemistry, theoretical and applied, Vol. 2, Churchill Livingston, London, 998 p.). For bleaching, sections were treated with 10% hydrogen peroxide for 36 hr and for the solubility test, sections were treated with 1% sodium hydroxide for at least 48 hr. Some metacercariae attached to the visceral epithelium of C. decisum, and others grown in chick embryos for 5 days (Shimazu, 1974, Jap. J. Parasitol. 23: 100-105) were fixed in NBF, sectioned on a cryostat, and stained with the Fontana method. Pigment droplets in the intestinal ceca of A. suwaense metacercariae stained black with the Fontana test, pale green with Nile Blue, dark green with alternate Nile Blue, and dark green with Ferro-ferricyanide. All of these reactions are indicative of melanin. Some pigment in the gut stained blue-green with Nile Blue, indicating the presence of lipofuchsins. The gut pigment was entirely bleached in hydrogen peroxide, but was not removed in sodium hydroxide. Results of the bleaching and solubility tests also indicate the pigment is melanin. Cryostat sections of A. suwaense metacercariae attached to the snail visceral epithelium stained intensely Fontana positive in the lumen of the worm intestinal ceca and in the snail visceral epithelium. The snail subepithelial tissue was Fontana negative, although some brown and orange pigment droplets were seen in the tissue. The intestine of A. suwaense cultured in chick embryos was devoid of pigment and stained Fontana negative. Amblosoma suwaense metacercariae ingest pigment by feeding on snail epithelium (Font, 1980, loc. cit.), and egest this pigment during culture. We thank Dr. William F. Font, Department of Biology, University of Wisconsin, Eau Claire, Wisconsin for supplying infected snails.

Thynnascaris rhacodes sp. n. (Nematoda : Ascaridoidea) in fishes from the Israeli Mediterranean coast

Thynnascaris rhacodes sp. n. infects Pelates quadrilineatus, Solea vulgaris, Boops boops, Lithognathus mormyrus, Obleida melanura, Diplodus vulgaris, D. sargus, and Sparus auratus from the eastern Mediterranean Sea. Unique in that the cuticle on the female tail is wrinkled, the ascaridoid is further characterized by possessing 27 to 35 precloacal papillae, a body length of 11 to 85 mm, similar spicules 3 to 6% of body length, a length-ratio of intestinal cecum to ventricular appendage of 1 : 1 to 5, and lips longer than wide.

Nutritional Implications of Surface Feeding by Gizzard Shad (Dorosoma cepedianum) on Insect Remains in an Ohio Reservoir

On six occasions during July and August 1975, surface feeding by schools of adult gizzard shad (Dorosoma cepedianum) on insect remains was observed in Acton Lake, Ohio. Proteinases in the digestive tract presumably hydrolyze the protein in the insect cuticle. The chitin component of the cuticle also has nutritive value, as significant chitinase activity was demonstrated in extracts of gizzard mucosa, hepatopancreas, and intestinal ceca. Values were comparable to activities observed in other fish species. Chitinolytic system activity was not demonstrated.The mean caloric equivalents of the chironomid and chaoborid exuviae and winged ants in surface debris were 5355, 4363, and 6059 cal/g ash-free dry wt, respectively. Ingestion of insect remains by this forage species could accelerate the return of energy and nutrients in these materials to higher trophic levels.

Studies on helminths of North Dakota. 8. Nematodes from the paddlefish, Polyodon spathula (Walbaum), including Thynnascaris dollfusi sp. nov. (Nematoda: Stomachidae).

Thynnascaris dollfusi sp. nov. is described from the stomach of Polyodon spathula (Walbaum) in North Dakota and reported from this host in Alabama. It has a short intestinal cecum, a long ventricular appendix, spicules 1.07 to 1.45 mm long, and a vulva situated at the junction of the first and second thirds of the body. Female Camallanus sp. is also reported.