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Macro-microscopic research in reideer (Rangifer tarandus) hoof suitable for efficient locomotion on complex grounds Texto completo
2017
Zhang, Rui | Qiao, Yu | Ji, Qiaoli | Ma, Songsong | Li, Jianqiao
Macro-microscopic research in reideer (Rangifer tarandus) hoof suitable for efficient locomotion on complex grounds Texto completo
2017
Zhang, Rui | Qiao, Yu | Ji, Qiaoli | Ma, Songsong | Li, Jianqiao
Introduction: Reindeer are adapted to long distance migration. This species can cope with variations in substrate, especially in ice and snow environment. However, few detailed studies about reindeer hoof are available. Thus this article describes the results of studies on macro- and micro-structures of reindeer hoof.Material and Methods: The gross anatomy of the reindeer hooves was examined. Stereo microscope (SM) and a scanning electron microscope (SEM) were used to observe four key selected positions of reindeer hooves. Moreover, element contents of the three selected positions of reindeer hooves were analysed using the SEM equipped with energy dispersive spectroscope.Results: Hoof bone structures were similar to other artiodactyl animals. In the microscopic analysis, the surfaces of the ungula sphere and ungula sole presented irregular laminated structure. Ungula edge surfaces were smooth and ungula cusp surfaces had unique features. Aside from C, O, and N, reindeer hooves contained such elements as S, Si, Fe, Al, and Ca. The content of the elements in different parts varied. Ti was the particular element in the ungula sole, and ungula edge lacked Mg and S which other parts contained.Conclusion: The macro- and micro-structures of the reindeer hooves showed high performance of skid and abrasion resistance. It is most probably essential to the long distance migration for the animals.
Mostrar más [+] Menos [-]Macro-microscopic research in reideer (Rangifer tarandus) hoof suitable for efficient locomotion on complex grounds Texto completo
2017
Zhang Rui | Qiao Yu | Ji Qiaoli | Ma Songsong | Li Jianqiao
Introduction: Reindeer are adapted to long distance migration. This species can cope with variations in substrate, especially in ice and snow environment. However, few detailed studies about reindeer hoof are available. Thus this article describes the results of studies on macro- and micro-structures of reindeer hoof.
Mostrar más [+] Menos [-]Taxonomic justification of the pathogenic strongylid infecting the Arabian camel Camelus dromedarius as Haemonchus longistipes by morphological and molecular phylogeny Texto completo
2019
Dajem, Saad | Morsy, Kareem | Al-Kahtani, Mohammed | Abdel-Gaber, Rewaida
Taxonomic justification of the pathogenic strongylid infecting the Arabian camel Camelus dromedarius as Haemonchus longistipes by morphological and molecular phylogeny Texto completo
2019
Dajem, Saad | Morsy, Kareem | Al-Kahtani, Mohammed | Abdel-Gaber, Rewaida
Introduction: There is still lack of morphological and phylogenetic information on the pathogenic nematode of the camel Haemonchus longistipes. In the present study, this parasite was isolated in Saudi Arabia and described. Material and Methods: The abomasa of two Arabian camels were collected from a slaughterhouse in Abha province and examined for nematode infection. Worms were described morphologically and morphometrically by electron microscopy. Multiple sequence alignment and the phylogenetic tree of the parasite were constructed from maximum likelihood analysis of its ITS-2 rDNA sequences. Results: These nematodes had a slender body terminating anteriorly at a conspicuous dorsal lancet. A pair of lateral cervical papillae distant from the anterior end was observed. The buccal aperture was hexagonal and surrounded by two amphids, six externo-labial papillae, and four cephalic papillae. Males terminated posteriorly at a bursa supported by spicules and lateral and dorsal rays. Females were linguiform and knobbed morphotypes with distinct ovijectors and a dorsal rim covering the anal pore. The taxonomy was confirmed by the morphology and number of the longitudinal cuticular ridges in a 43–46 range. The sequence alignment and phylogeny revealed 92% homology with H. longistipes (AJ577461.1), and the sequence was deposited into GenBank. Conclusion: The present study describes H. longistipes morphologically and molecularly which facilitates further discrimination of this species worldwide.
Mostrar más [+] Menos [-]Taxonomic justification of the pathogenic strongylid infecting the Arabian camel Camelus dromedarius as Haemonchus longistipes by morphological and molecular phylogeny Texto completo
2019
Dajem Saad | Morsy Kareem | Al-Kahtani Mohammed | Abdel-Gaber Rewaida
Introduction: There is still lack of morphological and phylogenetic information on the pathogenic nematode of the camel Haemonchus longistipes. In the present study, this parasite was isolated in Saudi Arabia and described.
Mostrar más [+] Menos [-]Characterisation of thrombocytes in Osteichthyes Texto completo
2019
Stosik, Michał | Tokarz-Deptuła, Beata | Deptuła, Wiesław
Characterisation of thrombocytes in Osteichthyes Texto completo
2019
Stosik, Michał | Tokarz-Deptuła, Beata | Deptuła, Wiesław
Thrombocytes in vertebrates other than mammals, inter alia in fish, are analogues of platelets in mammals. In Osteichthyes, these cells take part in haemostatic processes, including aggregation and release reactions in cases of blood vessel damage, and in the immune response development as well. This paper discusses the development of thrombocytes in Osteichthyes, taking into account the need to make changes to the concept of grouping progenitor cells as suggested in the literature. The following pages present the morphological and cytochemical properties of thrombocytes as well as their defence functions, and also point out differences between thrombocytes in fish and platelets in mammals. The paper further highlights the level of thrombocytes’ immune activity observed in fish and based on an increased proportion of these cells in response to antigenic stimulation, on morphological shifts towards forms characteristic of dendritic cells after antigenic stimulation and on the presence of surface structures and cytokines released through, inter alia, gene expression of TLR receptors, MHC class II protein-coding genes and pro-inflammatory cytokines. The study also points out the need to recognise thrombocytes in Osteichthyes as specialised immune cells conditioning non-specific immune mechanisms and playing an important role in affecting adaptive immune mechanisms.
Mostrar más [+] Menos [-]Characterisation of thrombocytes in Osteichthyes Texto completo
2019
Stosik Michał | Tokarz-Deptuła Beata | Deptuła Wiesław
Thrombocytes in vertebrates other than mammals, inter alia in fish, are analogues of platelets in mammals. In Osteichthyes, these cells take part in haemostatic processes, including aggregation and release reactions in cases of blood vessel damage, and in the immune response development as well. This paper discusses the development of thrombocytes in Osteichthyes, taking into account the need to make changes to the concept of grouping progenitor cells as suggested in the literature. The following pages present the morphological and cytochemical properties of thrombocytes as well as their defence functions, and also point out differences between thrombocytes in fish and platelets in mammals. The paper further highlights the level of thrombocytes’ immune activity observed in fish and based on an increased proportion of these cells in response to antigenic stimulation, on morphological shifts towards forms characteristic of dendritic cells after antigenic stimulation and on the presence of surface structures and cytokines released through, inter alia, gene expression of TLR receptors, MHC class II protein-coding genes and pro-inflammatory cytokines. The study also points out the need to recognise thrombocytes in Osteichthyes as specialised immune cells conditioning non-specific immune mechanisms and playing an important role in affecting adaptive immune mechanisms.
Mostrar más [+] Menos [-]Clarification of the status of Rhipicephalus kochi Donitz, 1905 (Ixodoidea, Ixodidae)
1983
Clifford, C.M. | Walker, J.B. | Keirans, J.E.
Rhipicephalus kochi, synonymy, description of female, male, nymph, and larva, scanning electron microscopy, brief report of laboratory life cycle study, review of host records and zoogeography in Africa, differentiation from R. pravus, R. punctatus, and R. appendiculatus
Mostrar más [+] Menos [-]Sarcocystis infection in the white-tailed deer (Odocoileus virginianus) in Montana: Intensity and description of Sarcocystis odoi n. sp
1983
Dubey, J.P. | Lozier, S.M.
Sarcocystis odocoileocanis, S. odoi n. sp., and Sarcocystis sp. found in muscles of white-tailed deer, measurements, ultrastructure; cat fed Sarcocystis-infected meat from deer shed sporocysts 24 days later which probably belonged to S. odoi n. sp.
Mostrar más [+] Menos [-]Parasites of South African freshwater fish. I. Some nematodes of the catfish (Clarias gariepinus (Burchell, 1822)) from the Hartbeespoort Dam
1982
Boomker, J.
nematodes of catfish, seasonal variation, measurements of Paracamallanus cyathopharynx and Procamallanus laeviconchus compared with those reported from other fish species recovered elsewhere in Africa
Mostrar más [+] Menos [-]Rhipicephalus zambeziensis sp. nov., a new tick from eastern and southern Africa, together with a redescription of Rhipicephalus appendiculatus Neumann, 1901 (Acarina, Ixodidae)
1981
Walker, J.B. | Norval, R.A.I. | Corwin, M.D.
Rhipicephalus zambeziensis n. sp., all stages of life cycle compared with life cycle of R. appendiculatus, redescription of R. appendiculatus, attempts to cross breed these 2 species in laboratory were unsuccessful thus validating their taxonomic separation, the 2 species can live sympatrically
Mostrar más [+] Menos [-]The development of Parafilaria bovicola in Musca xanthomelas and Musca lusoria
1981
Nevill, E.M.
Parafilaria bovicola, general appearance, size, developmental times, and site of development of each larval stage in potential vector flies (Musca xanthomelas and M. lusoria)
Mostrar más [+] Menos [-]Ixodes (Afrixodes) matopi n. sp. (Acarina: Ixodidae): A tick found aggregating on pre-orbital gland scent marks of the klipspringer in Zimbabwe
1981
Spickett, A.M. | Keirans, J.E. | Norval, R.A.I. | Clifford, C.M.
Ixodes (Afrixodes) matopi n. sp. is described from females and males collected off twigs bearing deposits of intraspecific communication marks secreted by the pre-orbital glands of the klipspringer Oreotragus oreotragus and from laboratory-reared immature specimens. One female was also found on a goat. The 4 collections were all from Zimbabwe, 3 of them from Matabeleland South Province and the fourth from Inyanga District, Zimbabwe.
Mostrar más [+] Menos [-]Studies on a bovine Babesia transmitted by Hyalomma marginatum rufipes Koch, 1844
1981
Gray, J.S. | De Vos, A.J.
Babesia occultans n. sp. originally obtained from engorged female Hyalomma marginatum rufipes collected from cattle in Northern Transvaal, transmission studies in laboratory strain of ticks and splenectomized cattle, morphological, serological, and cross-immunity studies distinguished parasite as previously undescribed species highly infective for H. marginatum rufipes but of low virulence in cattle, unsuccessful attempt to transmit transovarially with Boophilus microplus
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