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41.
Nitrogen-to-protein conversion factors were calculated for diets and fecal samples from three animal species fed low- or high-fiber diets. The conversion factors based on protein contents determined by amino acid analyses were calculated from total N (Kjeldahl analyses) and recovered amino acid plus NH3-N (amino acid analyses). Conversion factors based on protein contents determined by a fluorescamine assay for amino acids were also calculated from total Kjeldahl-N. The conversion factors based on Kjeldahl-N averaged 5.3 +/- .7 for the diets and 4.0 +/- .5 for the feces in the six animal and diet comparisons when calculated from anhydrous amino acid formula weights. The greatest deviations from the traditional 6.25 conversion factor occurred in the fecal samples of ruminant animals fed a corn-alfalfa meal diet at a maintenance level of intake. In contrast, conversion factors based on amino acid plus NH3-N were quite stable. These factors averaged 5.7 +/- .1 for feeds and 5.5 +/- .1 for feces when calculated from anhydrous amino acid residue weights. 相似文献
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Dietrich U 《Clinical Techniques in Small Animal Practice》2005,20(2):108-116
Cats are usually presented at a very late stage in the course of glaucoma when the eye is already blind. Secondary glaucoma because of another underlying ocular lesion is the most common form of glaucoma in the cat and is frequently associated with chronic anterior uveitis or intraocular neoplasia. Chronic stages of glaucoma in the cat are characterized by buphthalmus, anterior lens luxation, and exposure keratitis secondary to the enlarged globe. Ophthalmoscopic signs of glaucomatous retinal degeneration are only noticed in very advanced stages. Treatment of glaucoma in cats is usually aimed to keep the eye comfortable and within a normal intraocular pressure range. However, many antiglaucoma medications that are successfully used in humans and dogs are not very well tolerated by cats and, therefore, the selection of recommended drugs is limited in this species. 相似文献
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Rüfenacht S Marti E von Tscharner C Doherr MG Forster U Welle M Roosje PJ 《Veterinary dermatology》2005,16(2):94-101
The pathogenesis of equine urticaria is not well understood. In man, urticaria has been associated with immunological and nonimmunological mechanisms leading to the release of various mediators by mast cells. Skin biopsies of 32 horses with a history of urticaria were stained with toluidine blue, a double-labelling method for chymase and tryptase, and immunohistochemistry for immunoglobulin (Ig)E. These horses were compared with horses with pemphigus foliaceus, insect bite hypersensitivity and control horses with healthy skin. Neither formalin fixation time nor biopsy site influenced the staining methods. No chymase-positive cells were found. In all groups of horses, cells staining with toluidine blue and for tryptase and IgE were found in the epidermis and hair follicle papilla and significantly more positively staining cells were observed in the subepidermal dermis compared with the deep dermis. Horses with urticaria had significantly more IgE-bearing cells in the subepidermal dermis than control horses. However, horses with urticaria had significantly fewer toluidine-blue-stained mast cells in both subepidermal and deep dermis compared with the insect bite hypersensitivity and pemphigus foliaceus groups. This study suggests that IgE-mediated reactions play a role in the pathogenesis of urticaria. 相似文献
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Anaplasma infection in free-ranging Iberian red deer in the region of Castilla-La Mancha, Spain 总被引:4,自引:0,他引:4
De La Fuente J Vicente J Höfle U Ruiz-Fons F Fernández De Mera IG Van Den Bussche RA Kocan KM Gortazar C 《Veterinary microbiology》2004,100(3-4):163-173
Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, Anaplasma marginale, causes bovine anaplasmosis and infects erythrocytes of the vertebrate host and undergoes a complex developmental cycle in ticks which serve as biological vectors. Infected cattle, wild ruminants and ticks can all serve as reservoirs of A. marginale. In this study, hunter killed Iberian red deer (Cervus elaphus hispanicus) from the region of Castilla-La Mancha in southwestern Spain were tested for Anaplasma infection. We found that 10% of the deer examined were seropositive for Anaplasma. Three A. marginale strains were subsequently obtained from salivary glands of Hyalomma marginatum that were removed from these deer, and the sequence of the major surface protein (msp)4 gene was determined for each strain and used for phylogenetic studies. Maximum parsimony analyses of msp4 sequences from H. marginatum ticks in comparison with New World cattle and bison isolates reported previously, suggested different origins for these Spanish A. marginale strains. The results of this study demonstrated that Iberian red deer are naturally infected with Anaplasma, and may therefore serve as a wildlife reservoir of the pathogen. Although the link between deer infection and the strains of A. marginale identified in ticks was not established, H. marginatum and Rhipicephalus bursa were identified as potential biological vectors for A. marginale in this region and may effect transmission of A. marginale between deer and cattle populations. 相似文献
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Di Palma S Brunetti B Doherr MG Forster U Hilbe M Zurbriggen A Vandevelde M Oevermann A 《Comparative immunology, microbiology and infectious diseases》2012,35(5):429-441
This study examined the spatiotemporal immune response in listeric rhombencephalitis of ruminants in situ. Our data support the view that astrocytes facilitate the containment of infectious lesions. Results on the natural disease recapitulate observations in experimental rodent models and suggest that the mounted adaptive lymphocytic response of ruminants is effective in eliminating Listeria monocytogenes (LM). However, our data indicate earlier participation of the adaptive immune response, a stronger B lymphocyte contribution and a more protracted macrophage infiltration in the natural disease than it has been deduced from experimental models. Therefore, such models should be complemented by studies in natural host systems. Various macrophage and microglia subsets are involved in listeric rhombencephalitis and their differential contribution may account for species differences in clinical course and outcome of infection as might species differences in the B-cell response. Future functional ex vivo and in vitro studies are necessary to further investigate the findings obtained in the present study. 相似文献