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1.
Atopy.     
Atopy should be considered an immunological disorder that may result in several clinical conditions including respiratory disease, allergic dermatitis, food allergy dermatitis, and perhaps flea allergy dermatitis. The clinical course of the disease tends to fluctuate from season to season, which makes objective evaluation of injection therapy difficult. The disease is subject to both familial and environmental influences, and dogs maintain the atopic state throughout their life. The disease cannot be cured; however, a combination of symptomatic and specific injection therapy usually provides adequate control of the clinical signs. Owners of atopic dogs should appreciate that their pet has inherently itching skin, a cure for which is unlikely to be found.  相似文献   
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Sainfoin (Onobrychis viciifolia) is a tanniniferous, leguminous plant that has potentially beneficial effects on protein utilization in ruminants. As ensiling causes protein breakdown and elevated levels of buffer soluble N (BSN), we studied the distribution of N before and after ensiling sainfoin. Three varieties of sainfoin were either direct‐cut and frozen directly or wilted and frozen before later ensiling in mini‐silos with and without acidification with Promyr (PM; an acidifying commercial mixture of propionic and formic acid) and with or without polyethylene glycol (PEG). Extractable tannins (ET) and protein‐bound tannins (PBT) were measured with an HCl/butanol method in an attempt to correlate tannin levels to N fractions. The sainfoin silages showed good ensiling characteristics and had relatively high concentrations of undegraded protein. The effect of wilting on BSN levels (g/kg N) was dependent on sainfoin variety (P < 0·001). PEG increased and PM decreased the level of BSN in the silages (P < 0·001). PM treatment also produced less non‐protein N and ammonia‐N (P < 0·05) as compared with no additive. Addition of PEG to the silage increased the BSN‐proportion 1·8‐ and 2·6‐fold for both DM stages. A strong tannin‐protein binding effect is, therefore, confirmed in sainfoin. However, correlations between tannin levels (ET and PBT) and BSN were poor in the (non‐PEG) silages, indicating either that the HCl/butanol method is unsuitable for measuring tannin in silages or that qualitative attributes of tannins are more relevant than quantitative. The HCl/butanol method seems therefore not to be useful to predict degradation of protein in sainfoin silages.  相似文献   
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The objective of this study was to test for correlations between alopecia and ruminal drinking in young calves. 331 calves up to an age of 31 days were tested for evidence of generalized hair loss daily during their stay in the clinic. Incidence of diarrhoea and the results of ruminal fluid and blood analysis were compared between the groups with and without alopecia. Calves with alopecia showed a significantly higher incidence of diarrhoea and of ruminal acidosis persisting for at least 24 hours. Blood analysis revealed significant differences in degree of acidosis, in concentrations of D-lactate, urea, and creatinine in serum as well as in the activities of glutathione peroxidase, aspartate amino transferase, and creatine kinase. Alopecia in calves is correlated to longer periods of diseases, which are known to be accompanied by the production of D-lactate in the gastrointestinal tract, such as diarrhoea and ruminal drinking. The question, whether alopecia is due to formation of toxic substances or to deficiency of essential substances can not be answered.  相似文献   
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1. Durch intramuskulare Injektion von 0,5 mg des Prostaglandinanalogs ICI 80 996 beim Rind während der Gelbkörperphase des Zyklus kann nach 15–24 Stunden ein Abfall der Progesteronwerte unter 1 ng/ml Blutplasma und damit eine nachhaltige Luteolyse erreicht werden. Die sich anschließende Brunst ist ovulatorisch und feral. Das Präparat wird ohne Nebenwirkungen vertragen. 2. Durch zweimalige Injektion (d. h. je 1 mal 0,5 mg i. m.) im Abstand von 11 Tagen kann dieser Luteolyseeffekt zu Brunstsynchronisationen herangezogen werden; dabei ist eine Zykluskontrolle oder Brunstbeobachtung nicht erforderlich. 3. in 8 Feldversuchen konnte bei 213 Tieren ein Synchronisationserfolg von 90,6 % und, nach KB in der 1. induzierten Brunst, ein Konzeptionsergebnis von 54,7 % (bzw. von 60,1 %, wenn man die Auswertung auf die erfolgreich synchronisierten Tiere beschränkt) erzielt werden. Die KB bei 119 nicht behandelten Kontrolltieren, die in 5 dieser 8 Versuche zur Verfugung standen, war zu 60,3 % erfolgreich. 4. In einem Problembestand konnte die Fertilitätslage durch das biotechnische Vorgehen der Prostaglandinanwendung unmittelbar nicht verbessert werden 5. Die palpatorischen Ovarbefunde zum Zeitpunkt der KB ergaben, daß Tiere mit aprungbereiten Follikeln'zu 65 %, mit kleinen, nicht reifen Follikeln zu 50,8 % und mit bereitsgesprungenen Follikeln zu 15,8 % konzipierten. 6. Die bei einem Teil der Versuche eingesetzte zusdtzliche Behandlung mit 1,0 bzw. 1,5 mg des Gonadotropin-Releasinghormons (LRH-Hoechst 471) i. m. zum Zeitpunkt der Besamung zeigte bezüglich des Konzeptionsergebnisses eine positive Tendenz.  相似文献   
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OBJECTIVE: To characterize clinical and hematologic responses in dogs following experimental inoculation with Babesia gibsoni-like isolates from infected dogs in Oklahoma. DESIGN: Prospective study. ANIMALS: 6 mixed-breed dogs. PROCEDURE: 2 dogs were inoculated with organisms from a naturally infected dog, and 3 were inoculated with organisms from a second naturally infected dog (1 of these 3 dogs was splenectomized 1 week prior to inoculation). One dog was not inoculated. Complete blood counts were performed weekly. RESULTS: In the 5 dogs inoculated with organisms, parasites were initially detected 1 to 5 weeks after inoculation, and severity of parasitemia peaked with 1.9 to 6.0% of RBC infected by 4 to 6 weeks after inoculation. Parasitemia was easily detectable (> 0.1% of RBC infected) for 3 to 4 weeks. Clinical abnormalities included lethargy, fever, and pale mucous membranes but were mild to nearly inapparent in 2 dogs. All dogs developed regenerative anemia and marked thrombocytopenia. Thrombocytopenia developed before and lasted longer than the parasitemia. Profound but transient neutropenia was detected in some dogs. The splenectomized dog developed more severe parasitemia and anemia and more pronounced clinical abnormalities. Three dogs with intact spleens recovered without treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 2 or more genotypically distinct, but morphologically identical, small Babesia parasites can infect dogs in the United States. Compared with infection with small Babesia parasites from California, infection with these isolates resulted in less severe parasitemia and clinical abnormalities. Parasitemia was transient, indicating that identification of organisms in blood smears may be difficult in some dogs.  相似文献   
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Litter decomposition was studied for 2 years in a mixed forest serving as a water protection area (Rhine-Neckar conurbation, SW Germany). Two experiments differing in initial dry weight equivalent in litterbags were set up: one to compare decomposition of European beech leaves (Fagus sylvatica) with common oak leaves (Quercus robur), and the other comparing decomposition of Scots pine needles (Pinus sylvestris) with black cherry leaves (Prunus serotina Ehrh.), respectively. Mass losses were greater for oak litter than for beech (75.0 versus 34.6%), and for cherry litter than for pine (94.6 versus 68.3%). In both experiments, a strong initial loss of soluble compounds occurred. The changes in litter N and P concentrations and the decrease in C-to-N ratio coincided with changes in residual mass. However, neither tannin and phenolic concentrations nor NMR could explain the pronounced variation in mass loss after 2 years. Differences in litter palatability and toughness, nutrient contents and other organic compounds may be responsible for the considerable differences in residual mass between litter types. The fast decay of black cherry leaves appears to play a major role in the present humus dynamics at the studied site. Since black cherry has a high N demand, which is mainly met by root uptake from the forest floor, this species is crucial for internal N cycling at this conurbation forest site. These effects together may significantly contribute to prevent nitrate leaching from the forest ecosystem which is subject to a continuous N deposition on an elevated level.  相似文献   
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