Synopsis of Digenetic Trematodes of Vertebrates

Studies on the Helminth fauna of Japan,pt.56.

We monitored the prevalence of endoparasitic infections of rodents in Punjab State, India, between January 2004 and December 2005. Three species of wild rodents, namely the house rat, Rattus rattus (n= 42), the lesser bandicoot rat, Bandicota bengalensis (n= 34) and the Indian gerbil, Tatera indica (n= 15), were live-captured from houses and crop fields. Examination of various organs revealed that the highest rates of endoparasitic infection occurred in R. rattus (40.5%), followed by B. bengalensis (35.3 %) and then T. indica (20.0%), with an overall infection rate of 35.2%. All three rodent species were found naturally infected with one or more species of helminths. Metacestodes (1-6) of Cysticercus fasciolaris (larvae of Taenia taeniaeformis) were found in all three rodent species (in the liver). In one male T. indica, numerous robust T. taeniaeformis metacestodes were found in oval sacs attached to the mesentery and the abdominal wall, an unusual site. The cauda epididymal fluid of the same gerbil was also found to be infected with a very rare species of strongylid nematode, which could not be identified to genus or species level. It is possible that this nematode is transmitted sexually and thus may affect the reproductive potential of gerbils. This appears to be the first report of this phenomenon. In one B. bengalensis individual, the intestine was found to be obstructed with an acanthocephalan, Moniliformis moniliformis, with concurrent infection with C. fasciolaris in the form of multiple cysts in the liver. Although no natural protozoan infection was found in these field rodents, experimental Trypanosoma evansi infection has been established in all three species with high pathogenicity, and the possibility of sexual transmission was supported by the presence of T. evansi in the cauda epididymal fluid of male rats.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1749-4877.2008.00071.x

Rodents as reservoirs of parasites in India

Proliferative kidney disease (PKD) is an emerging disease of salmonid fishes. It is provoked by temperature and caused by infective spores of the myxozoan parasite Tetracapsuloides bryosalmonae, which develops in freshwater bryozoans. We investigated the link between PKD and temperature by determining whether temperature influences the proliferation of T. bryosalmonae in the bryozoan host Fredericella sultana. Herein we show that increased temperatures drive the proliferation of T. bryosalmonae in bryozoans by provoking, accelerating and prolonging the production of infective spores from cryptic stages. Based on these results we predict that PKD outbreaks will increase further in magnitude and severity in wild and farmed salmonids as a result of climate-driven enhanced proliferation in invertebrate hosts, and urge for early implementation of management strategies to reduce future salmonid declines.

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Temperature-driven proliferation of Tetracapsuloides bryosalmonae in bryozoan hosts portends salmonid declines

Cercaria cerastodermae I, a digenean parasite of Cerastoderma edule, was recorded for the first time in the Atlantic Ocean off the Iberian peninsula. Sporocysts were present in the hemolymph of the digestive gland, gonad, gills, and foot of the mollusc. Most of the cercariae present within sporocysts were encysted as metacercariae. The corresponding adult stages were obtained after experimental infection of several Diplodus sargus artificially reared in fish farms and that had previously been protected against natural infections. Numerous adult specimens of Monorchis parvus were collected in Diplodus annularis along the French Mediterranean coast. Comparison of wild and experimental adults allowed the adult stage of Cercaria cerastodermae I to be identified as M. parvus. Another monorchid, Monorchis monorchis, a parasite of Spondyliosoma cantharus, was found in the same Mediterranean area and compared with M. parvus. Additionally, ITS1 nuclear ribosomal DNA sequences of C. cerastodermae I and of the adults collected in naturally infected D. annularis and S. cantharus were obtained. Sequence data indicate that C. cerastodermae I corresponds to the adult of M. parvus found in D. annularis and is clearly distinct from M. monorchis found in S. cantharus.

The life cycle of monorchis parvus (digenea: monorchiidae) demonstrated by developmental and molecular data

The present work was undertaken to study the histopathological changes in the intestine of male rat Nesokia indica. Histopathological sections of infected intestine were prepared by fixing small pieces of intestine in buffer formalin for 24 h. The fixed material was washed with 70% alcohol and dehydrated and cleared for paraffin block making by the usual procedure. Sections of 5 to 7 µ thickness were used for the present study. E & H stained serial sections were mounted permanently in DPX. Sections were examined in detail and photomicrographs of selected sections were taken by Nikon (Optiphot-2) photomicroscope using Fuji colour film. Histopathological study of selected portions of the intestine revealed that nematode parasites severely affected the whole thickness of the intestinal wall. Pronounced changes included atrophy of the villi and underlying tissue as a common finding. Gran- ulomatous tissue masses and granulation lesions were also obvious. Hypertrophy and hyperplasia of the glandular region were seen. Pedunculate edema forming a condition like sessile villous adenoma was an important finding.

https://journals.tubitak.gov.tr/zoology/issues/zoo-04-28-4/zoo-28-4-10-0306-7.pdf

Histopathologic Alterations Associated with Syphacia sp. (Nematode) in the Intestine of Nesokia indica

Rhabdochona (Rhabdochona) parastromatei sp.n. is characterized by its relatively large body size, 16 teeth in pros tome, right spicule 0.48-0.50 mm and left 0.10-0.12 mm in length, 9–10 pairs of caudal papillae, a single adanal papilla, eggs in female 0.029-0.044 by 0.018-0.025 mm in size, and by having a marine fish host.

Rhabdochona parastromatei sp.n. (Nematoda, Rhabdochonidae) from the Fish Parastromateus niger (Bleeker) of the Karachi Coast

During a survey of helminth parasites of fishes twelve trematodes were collected from the small intestine of fish Channa (Ophiocephalus) striatus (Bl.) and Channa (Ophiocephalus) maculatus (Bl.) and identified as Genarchopsis gibsoni new species and G. kalriai Bilqees and Khan, 1991. The present new species is separated from the previously described species of the genus in having body elongate, rounded at anterior extremity, narrower at hind body and bluntly pointed at posterior extremity, widest at the acetabular region. Forebody much longer than hindbody. Pharynx oval. Prepharynx and esophagus absent. Acetabulum near the posterior end, very large almost occupying the whole width of the body. Testes, postacetabular and transversely elongated. Genital opening at the level of the posterior margin of the pharynx. Cirrus sac long, intercecal, curved dorsally containing prominent elongate seminal vesicle and long pars prostatica. Vitellaria consist of two very small, dark, elongate masses. Ovary, vitellaria and testes are all close to each other. Uterus occupying preacetabular region and reach to end of ceca posterior to acetabulum. While G. kalriai Bilqees and Khan, 1991 is being reported from a different host, earlier this species was reported from freshwater fish Channa (Ophiocephalus) marulius (Ham.)

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A new trematode of the genus Genarchopsis Ozaki, 1925 from freshwater fish of Sindh, Pakistan.

Opisthorchis jonesae new species is described and illustrated. It is distinguished by possessing a long esophagus, absence of prepharynx and an elongate body shape. It is closely related to O. cheelis, but differs in body size, egg size and shape of testes.

A New Trematode From the Intestine of Kite, Milvus migrans migrans

Three trematodes are described from three different species of Karachi coast fishes. Complexo-bursa magna sp.n., from Lates calcarifer, is characterized by its large body size, unlotxjd rounded ovary, large operculate eggs, and numerous vitelline follicles extending from the preacetabular region to the posterior end of the body. Monorchis heterorchis sp.n., from the fish Muraenesox cinereus, is also characterized by its relatively large body, median transversely elongated testes of variable shapes, ovary consisting of four distinct follicles and relatively large operculate eggs. Waretrema piscicola Srivastava, 1937 is reported here from the Karachi coast 17 years after its last report from the Philippines, in the same host (Scato-phaugs argus) but from a new locality.

Fatima Mujib Bilqees

Papers

Histopathologic Alterations Associated with Syphacia sp. (Nematode) in the Intestine of Nesokia indica

Rhabdochona parastromatei sp.n. (Nematoda, Rhabdochonidae) from the Fish Parastromateus niger (Bleeker) of the Karachi Coast

A new trematode of the genus Genarchopsis Ozaki, 1925 from freshwater fish of Sindh, Pakistan.

A New Trematode From the Intestine of Kite, Milvus migrans migrans

Three Trematodes Including Two New Species from Fishes of the Karachi Coast