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Macro-microscopic research in reideer (Rangifer tarandus) hoof suitable for efficient locomotion on complex grounds
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.
اظهر المزيد [+] اقل [-]Characterisation of thrombocytes in Osteichthyes
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.
اظهر المزيد [+] اقل [-]Taxonomic justification of the pathogenic strongylid infecting the Arabian camel Camelus dromedarius as Haemonchus longistipes by morphological and molecular phylogeny
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.
اظهر المزيد [+] اقل [-]Haemonchus contortus from the vaal ribbok, Pelea capreolus, and the bontebok, Damaliscus dorcas dorcas, in the Bontebok National Park
1983
Boomker, J. | Horak, I.G. | Gibbons, L.M. | De Vos, V.
Haemonchus contortus with exceptionally long spicules recovered from vaal ribbok and bontebok, measurements
اظهر المزيد [+] اقل [-]Notes on African Haemaphysalis ticks. XV. H. (Rhipistoma) norvali sp. n., a hedgehog parasite of the H. (R.) spinulosa group in Zimbabwe (Acarina: Ixodidae)
1983
Hoogstraal, H. | Wassef, H.Y.
The male, female, nymph, and larva of Haemaphysalis (Rhipistoma) norvali sp. n., are described and compared with other members of the H. (R.) spinulosa group. Adult H. (R.) norvali parasitize the southern African hedgehog, Erinaceus frontalis Smith, in Matabeleland, Zimbabwe. Immatures were reared on a laboratory rabbit.
اظهر المزيد [+] اقل [-]A revision of the genus Impalaia Monnig, 1924
1977
Boomker, J.
revision of Impalaia, 3 valid species (I. tuberculata (type species), I. nudicollis, I. okapiae), descriptions, measurements, host-parasite list, synonymy, "I. taurotragi (Le Roux, 1936) appears to be an aberrant form of I. nudicollis."
اظهر المزيد [+] اقل [-]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.
اظهر المزيد [+] اقل [-]Development of Sarcocystis alceslatrans Dubey, 1980, in the small inntestine of dogs
1983
Colwell, D.D. | Mahrt, J.L.
Sarcocystis alceslatrans, dogs fed moose musculature shed sporocysts in feces, endogenous development in small intestine, ultrastructure of oocyst and sporocyst walls during sporogony, intestinal inoculation; coyote and cats fed sarcocyst-infected moose meat did not pass oocysts or sporocysts in feces
اظهر المزيد [+] اقل [-]Ultrastructure of amastigotes of Leishmania donovani in the bone marrow of a dog
1982
Simpson, C.F. | Harvey, J.W. | French, T.W.
Leishmania donovani, amastigotes from dog marrow macrophages, ultrastructure
اظهر المزيد [+] اقل [-]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
اظهر المزيد [+] اقل [-]