The current report describes granulomatous pneumonia due to Spirocerca lupi in 2 free-ranging maned wolves (Chrysocyon brachyurus). Both wolves had multiple, white, 1-1.5 cm in diameter, soft, encapsulated granulomas in the caudal lung lobes, which contained centrally placed parasites on cut sections.
View Article and Find Full Text PDFMarshallagia lichtenfelsi sp. n. is a dimorphic ostertagiine nematode occurring in the abomasum of mountain goats, Oreamnos americanus, from the Western Cordillera of North America.
View Article and Find Full Text PDFCollections to explore helminth diversity among free-ranging ungulates in the North American Arctic revealed the occurrence of a third male, or " davtiani ," morphotype for Teladorsagia boreoarcticus . Designated as T. boreoarcticus forma (f.
View Article and Find Full Text PDFResistance to modern anthelmintics by ruminant nematode parasites is an increasing problem throughout the world. To date the problem has largely been reported in parasites of small ruminants, but there are increasing reports of such resistance in nematodes recovered from cattle. Until now there have been no published reports of drug resistant parasites from cattle in North America.
View Article and Find Full Text PDFWe previously documented the appearance of cattle nematode parasites resistant to avermectins, milbemycin, and a benzimidazole at the end of a grazing season in a backgrounding operation in the upper Midwestern US. To further characterize the pattern of drug resistance, we extended the study to (1) monitor the animals over the course of the grazing season; (2) increase the number of animals slaughtered at the end of the season to minimize the effect of potential outlying observations; (3) increase the time interval between treatment and slaughter to ensure sufficient time for drug action; (4) utilize repeated fecal sampling in the fecal egg reduction test to minimize procedural variation; (5) increase the number of drugs tested. The results of the present study were in agreement with those of the previous study and demonstrated that during the course of the grazing season the pastures harbored significant numbers of parasites that were refractory to avermectins, milbemycin, and a benzimidazole at the label recommended doses.
View Article and Find Full Text PDFThe independence of Pseudomarshallagia and its placement among the medium stomach worms of ungulates, Ostertagiinae, is confirmed based on comparative morphological studies of the synlophe and genital attributes among male and female specimens. An emended description of Pseudomarshallagia elongata is presented based on a series of specimens in sheep from northern Ethiopia. Pseudomarshallagia elongata is retained among the 15 genera of the Ostertagiinae based on presence of a prominent esophageal-intestinal valve, paired "0" papillae, a modified accessory bursal membrane containing the paired "7" papillae, and configuration of the copulatory bursa.
View Article and Find Full Text PDFAfricanastrongylus giganticus n. sp. is described based on large ostertagiine nematodes occurring in the abomasum of African buffalo, Syncerus caffer, from Uganda; this represents the second species recognized in the genus.
View Article and Find Full Text PDFThe synlophe, or system of longitudinal cuticular ridges characteristic of some trichostrongyloid nematodes, is examined in detail for 6 of 8 species in Longistrongylus (Ostertagiinae) that occur in ungulates across sub-Saharan Africa. Among the species of Longistrongylus examined, 5 are characterized by a tapering pattern laterally in the cervical zone (anterior to the esophageal-intestinal junction), which is largely consistent among multiple male and female specimens; in contrast, for Longistrongylus meyeri the lateral pattern is parallel. The synlophe is bilaterally symmetrical, with ridges extending from the base of the cephalic expansion to near the caudal extremity in males and females.
View Article and Find Full Text PDFAbomasal nematodes (Ostertagiinae: Trichostrongyloidea), representing a previously unrecognized genus and species, were discovered in kob (Kobus kob) and kongoni (hartebeest) (Alcelaphus buselaphus jacksoni) from Uganda during surveys of ungulate parasites in the 1960s. Robustostrongylus aferensis gen. nov.
View Article and Find Full Text PDFAs part of a revision of the systematics of the Cyathostominea of equids, we determined that the single type-specimen of Cylicocyclus adersi Boulenger, 1920 is missing and a modern description of this rare species parasitic in donkeys Equus asinus L. and zebras E. burchelli (Gray) and E.
View Article and Find Full Text PDFThe use of ovejector structure in the phylogeny of the Haemonchinae is hampered by differences among nematologists in the application of terminology and the recognition of homologous parts. Some workers recognize a sphincter with 2 parts, but others recognize only the proximal, rounded part of the sphincter and include the distal cylindrical part of the sphincter with the vestibule. The results of this study demonstrate that all sphincters of Haemonchinae of ruminants have 2 parts.
View Article and Find Full Text PDFIn the course of a revision of Haemonchus Cobb, 1898 (Nematoda), commonly referred to as large stomach worms, significant new morphological information was discovered that allows the recognition of 2 species believed for more than 50 yr to be synonymous. Both species, Haemonchus mitchelli Le Roux, 1929, from the eland Taurotragus oryx and other African ruminants and H. okapiae van den Berghe, 1937, from the okapi Okapia johnstoni, have a synlophe of 42 ridges, but the synlophe of H.
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