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41.
3 colostomized laying hybrids received orally with a conventional ration 1% urea with 96.06 atom-% 15N excess (15N'). over a period of 6 days. In the period of the experiment every hen consumed 2.87 g 15N'. After another 2 days, on which they received conventional feed urea, the animals were butchered. 15N' was determined in the total N and in 15 amino acids of the oviduct. Of the 15 amino acids the labelling of glutamic acid, glycine and serine was highest and on average amounted to 0.80, 0.66 and 0.67 atom-% 15N'. In lysine and arginine only 0.10 and 0.11 atom-% 15N' could be detected. The amino acid N with natural isotopic frequency amounted to a quarter for the basic amino acids, a tenth for the branched chain ones and for the non-essential ones (glutamic acid, aspartic acid, serine, glycine, alanine, proline) a third of the total oviduct 14N, The average quota of 15N' is only 3.6%, that of the branched chain amino acids 4.5 and that of the non-essential ones 21.1%. Consequently, the 15N' of the urea is mainly used for the synthesis of the non-essential amino acids of the oviduct. 相似文献
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The colostomised hens received 15N-labelled wheat. For a period of 8 days the incorporation of the 15N excess (15N') into the albumen, the yolk and the egg-shell was measured. In addition to that, the values for atom-percent of 15N' in the amino acids lysine, histidien and arginine of the albumen and the yolk were ascertained. The egg-shell and the albumen were labelled shortly after the beginning of the experiment. In both fractions the atom-per cent of 15N' rises more quickly than in the yolk. After the withdrawal of the labelled feed the decrease in the yolk was slower than in the egg-shell and the albumen. Concerning the atom-per cent of 15N' there is hardly a difference between the total N and the amino acids. Despite the different supply with amino acids, the relation of histidine 15N' : lysine 15N' : arginine-15N' in the yolk and the albumen remains largely constant. It is 1 : 2 : 3 and corresponds to the quantitative relation of the N content of the three amino acids in the egg protein. The utilisation of 14N and 15N' of the wheat lysin for the egg synthesis amounts to approximately 50%. There are considerable differences between the utilisation of 15N' of the histidine and 15N' of the arginine and the 14N of the two dietary amino acids. 相似文献
44.
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
48.
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
49.
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
50.