Orloffia		Contents		Rev 03/08/2024
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Orloffia Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Haemonchidae Menu		Feeding		References
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Classification

Chromadorea

Chromadoria

Rhabditida

  Rhabditina

   Trichostronglyloidea

    Haemonchidae

Ostertagiinae

Orloffia Drozdz, 1965

Type species of the genus: Orloffia bisonis Chapin, 1925

Synonyms:

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Morphology and Anatomy:

Opinions differ on the taxonomic independence and specific composition of the genus Orloffia. Some consider Orloffia bisonis and O. orloffi to be synonumous. Others consider O. bisonis to be a member of the genus Ostertagia although Drozdz (1995) points to significant differences in the pattern of rays in the male bursa.  Many consider O. dahurica a lasrger variant of O. bisoins (Kuznetsov, 2011).

Analysis of ITS2 seuences of rDNA of the genus Orloffia do not differ among nematodes determined imorphologically and morphometrically as O. bisonis, O. kasakhstanica, O. dahurica, and O. buriatica. Kuznetsov (2011) concluded that the only valid species in the genus Orloffia is Orloffia bisonis, which has males representing two morphs, O. bisonis and minor O. kasakhstanica.  Further, differences in ITS2  in Orloffia spp. and representatives of the genera Ostertagia, Teladorsagia, and Trochostrongylus nor justify synonymization of Orloffia and Ostertagia.

• Female: Male:

  Bursa of Orloffia orloffi (Sankin, 1930) (=O. bisonis?) (Haemonchidae, Ostertagiinae), ventral view. Rays numbered per Chabaud et al (1970): 0, unpaired pre-cloacal papilla; 1, pre-bursal papilla; 2, ventro-ventral ray; 3, ventro-lateral ray; 4, 5, 6, lateral trident of rays composing the lateral trunk; 4, externo- (or antero-) lateral ray; 5, medio-lateral ray; 6, postero-lateral ray; 7, paired papillae on dorsal opening of cloaca; 8, externo-dorsal ray. Width of bursa approx. 0.5 mm Adapted from Beveridge et al., 2013

..

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Distribution

Parasites of the abomasum  of domestic and wild ruminants.

Reported from Russia, Belarus, Kazakhstan, Uzbekistan, Mongolia, the United States, and Canada (Kuznetsov, 2011).

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Economic Importance:

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Hosts:

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Feeding

Many of the species are parasites of the abomasa and small intestine of ruminants.

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Life Cycle:

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Damage:

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Management:

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References:

Beveridge, I., Spratt, D.M., Durette-Desset, M-C. 2013. Order Strongylida (Railliet & Henry, 1913). Handbook Of Zoology Online. De Gruyter

Chabaud, A. G., Puylaert, F., Bain, O., Petter, A. J., Durette-Desset, M.-C. 1970. Remarques sur l’homologie entre les papilles cloacales des Rhabditides et les cotes dorsales des Strongylida. C. R. Hebd. Seances Acad. Sci. 271: 1771-1774.

Drozdz, J., 1995. Polymorphism in the Ostertagiinae Lopez Neyra, 1947 and Comments on the Systematics of These Nematodes, Syst. Parasitol., 1995, 32:91-99.

Kuznetsov, D.N. 2011. Taxonomic Revision of the Genus Orloffia (Nematoda: Ostertagiinae) Based on an ITS2 rDNA Study. Biology Bulletin, 38:608-614. Original Russian Text: Kuznetsov, D.N. 2011, in Izvestiya Akademii Nauk, Seriya Biologicheskaya, 2011, 6: 710-16.

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