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Results for “Parasitology”

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At least 217 records · Page 12Linked to original sources
USGS1979

The parasitic coelenterate, Polypodium hydriforme Ussov, from the eggs of the American acipenseriform Polyodon Spainthula

No significant differences in macro- and micromorphology were found between the parasitic stolon and free-living polyps of Polypodium sp. obtained from infected eggs of the North American acipenseriform fish Polyodon spathula and corresponding developmental stages of Polypodium hydriforme Ussov, parasitic in the Volga sterlet ( Acipenser ruthenus ). Therefore, both the American and the European forms of Polypodium belong to the species P. hydriforme Ussov.

Missouri↗
USGS1983

The white pelican (Pelicanus erythrorhynchos) as a host of Pelecanectes apunctatus (Acarina: Hypoderidae)

Several species of nymphs from the family Hypoderidae have been reported from pelecaniform birds (Cerny, 1969, Folia Parasit. (Praha) 16:271-274; Pence, 1972, J. Med. Ent. 9: 435-438; Pence and Courtney, 1973, J. Parasitol. 59: 711-718); however, there are no records from the white pelican, Pelecanus erythrorhynchos . I report here the occurrence of hypopi from this host species.

Texas↗
USGS1991

Increased population densities of Amblyomma americanum (Acari: Ixodidae) on Long Island, New York

Lone star ticks, A mblyomma americanum comprised a significantly greater proportion of total ticks flagged on eastern Long Island and Fire Island, New York, in 1986 and 1990 than in samples reported by other authors from the 1940s (when A. americanum was not collected by flagging or from hosts) and the 1970s. Therefore, population densities of A. americanum apparently have increased in recent years on southeastern Long Island, where this species now is distributed widely.

Journal of Parasitology↗
USGS1996

Haemoproteus iwa n. sp. in great frigatebirds (Fregata minor [Gmelin]) from Hawaii: Parasite morphology and prevalence

We describe a new species of Haemoproteus Kruse, 1890 from great frigatebirds ( Fregata minor [Gmelin]) captured on Tern Island-French Frigate Shoals and Laysan Island in Hawaii. Parasite prevalence on Laysan Island (35%) was not significantly different than that of Tern Island (36%). On Laysan, prevalence was highest in juveniles (52%), followed by adult males (29%) and adult females (19%). Prevalence on Tern was 36% both for adult females and juveniles, and 28% for adult males. Parasitemia was low (mean < 2 parasites/10,000 red blood cell). Parasitized red cells had significantly greater areas than unparasitized cells. We named this parasite Haemoproteus iwa after the Hawaiian name for frigatebirds (iwa). This is the first documentation of a hemoparasite from tropical pelagic seabirds in Hawaii and the first description of an endemic hemoparasite in the archipelago.

Hawai'i↗
USGS1997

Description and epizootiology of Babesia poelea n. sp. in brown boobies (Sula leucogaster (Boddaert)) on Sand Island, Johnston Atoll, Central Pacific

We describe a new species of piroplasm from brown boobies (Sula leucogaster) on Sand Island, Johnston Atoll National Wildlife Refuge, central Pacific. Mean parasitemia in adults and chicks was less than 1%, with the parasitemia in chicks significantly greater than in adults. There was no significant relation between the age of chicks and the degree of parasitemia. Parasitized red cells and red cell nuclei were significantly smaller than those of unparasitized cells, and infected birds appeared clinically normal. Prevalence of the parasite in chicks (54%) was significantly greater than in adults (13%), and the geographic distribution of parasitized chicks was skewed toward the eastern end of Sand Island. On the basis of morphologic characteristics, we named it Babesia poelea. The specific name is a concatenation of the Hawaiian names for dark (po'ele) and booby ('a). This is the second documentation of an endemic avian hemoparasite in seabirds from the central Pacific.

Johnston Atoll↗
USGS1997

Pathogenicity of entomopathogenic fungus Metarhizium anisopliae (Deuteromycetes) to Ixodes scapularis (Acari: Ixodidae)

The entomopathogenic fungus Metarhizium anisopliae is highly pathogenic to the black-legged tick, Ixodes scapularis. Spore concentrations of 108/ml for engorged larvae and 107/ml for engorged females resulted in 100% tick mortality, 2 wk post-infection. The LC50 value for engorged larvae (concentration to kill 50% of ticks) was 107 spores/ml. Metarhizium anisopliae shows considerable potential as a microbial control agent for the management of Ixodes scapularis.

Journal of Parasitology↗
USGS1997

Acanthocephala of the bald eagle (Haliaeetus leucocephalus) in North America

Examination of bald eagles (Haliaeetus leucocephalus) collected from several locations in North America contributed new information concerning the acanthocephalan fauna of this host. Representatives of Arythmorhynchus brevis, representing a new host record, were collected from eagles in Florida, New Hampshire, and Wisconsin. Plagiorhynchus sp. was collected from an eagle in Florida. Corynosoma strumosum was collected from an eagle in Alaska. Andracantha phalacrocoracis, representing a new host record, was collected from an eagle in Alaska. Southwellina hispida, representing a new host record, was collected from eagles in Maine and Virginia. The occurrence of gravid or mature females of A. brevis, Plagiorhynchus sp., and S. hispida suggests that the bald eagle may serve as a competent definitive host for these species.

Alaska, Florida, Maine, New Hampshire, Virginia, W↗
USGS1997

Spatial distribution of larval Ixodes scapularis (Acari:Ixodidae) on Peromyscus leucopus and Microtus pennsylvanicus at two island sites

Larval blacklegged ticks, Ixodes scapularis , were collected from white-footed mice, Peromyscus leucopus , on Prudence Island (where Microtus pennsylavanicus were not captured) and from meadow voles, M. pennsylvanicus , on Patience Island (where P. leucopus was absent) in Narragansett Bay, Rhode Island from June to October 1992. Ixodes scapularis larvae were also collected by flagging in the vicinity of host captures. On both islands, the relative density of larvae changed from July to September in samples from hosts, but not in flagging samples. Consequently, different sampling techniques can give different assessments of tick populations. Larvae were highly aggregated on both of the host species throughout the sampling period. As the mean relative density of larvae increased in the environment (based on flagging samples), larvae on the hosts became more dense and more crowded. Increased densities of larvae in the environment were not correlated with increased patchiness in the distribution of larvae among host animals on either island. Changes in the spatial distribution of larval I. scapularis on each host species had similar trends as larval densities and distributions within the environment. These results suggest that M. pennsylvanicus can serve as an alternative host for immature I. scapularis in a P. leucopus -free environment and have similar distributional characteristics.

Journal of Parasitology↗
USGS1957

Some myxosporidia found in Pacific Northwest salmonids

During the histological examination of a group of wild and hatchery salmonids undescribed sporazoans were frequently observed. This was not unexpected, since Myxosporidia are typical fish parasites (Kudo, 1920). Myxidium were observed in kidney tubules, Cholromyxum in glomeruli, and Myxobous in the spinal cord and on epidermal scales. The present paper will deal with the description and indentification of these unclassified Myxosporodia.

Oregon, Washington↗
USGS2016

Chewing lice of swan geese (Anser cygnoides): New host-parasite associations

Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius domesticus Arnold, 2005, and 1 Anaticola anseris (Linnaeus, 1758). These species are known from other geese and swans, but all of them were new to the swan goose. This result also indicates no overlap in lice species between older records and our findings from wild birds. Thus, ectoparasites collected from domestic or captive animals may provide biased information on the occurrence, prevalence, host selection, and host-ectoparasite interactions from those on wild hosts.

The Korean Journal of Parasitology↗
USGS2008

Modest genetic differentiation among North American populations of Sarcocystic neurona may reflect expansion in its geographic range

Sarcocystis neurona is an important cause of neurological disease in horses (equine protozoal myeloencephalitis, EPM) and sea otters in the United States. In addition, EPM-like disease has been diagnosed in several other land and marine mammals. Opossums are its only definitive hosts. Little genetic diversity among isolates of S. neurona from different hosts has been reported. Here, we used 11 microsatellites to characterize S. neurona DNA isolated from natural infections in 22 sea otters (Enhydra lutris) from California and Washington and in 11 raccoons (Procyon lotor) and 1 striped skunk (Mephitis mephitis) from Wisconsin. By jointly analyzing these 34 isolates with 26 isolates previously reported, we determined that geographic barriers may limit S. neurona dispersal and that only a limited subset of possible parasite genotypes may have been introduced to recently established opossum populations. Moreover, our study confirms that diverse intermediate hosts share a common infection source, the opossum (Didelphis virginiana).

California, Washington↗