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31.
32.
The reproductive efficiency of stabled domestic stallions is often lower than what could be expected from observations in feral herds. In the wild, stallions typically live with mares in harem bands, with other stallions in bachelor bands, or occasionally in mixed-sex transitional bands. We, therefore, argue that permanent contact with mares may increase reproductive efficiency of stallions suffering from low libido and/or fertility. We also provide a summary of our present knowledge of natural conditions, management, and husbandry of domestic stallions, and of intra- and intersexual behavioral interactions in horses.  相似文献   
33.
In this study we describe the generation of monoclonal antibodies (mAbs), which recognize different epitopes of the equine IgE constant heavy chain. Equi-murine recombinant IgE (rIgE), composed of the murine V(H)186.2 heavy chain variable region, linked to the equine IgE constant heavy chain and expressed together with the murine lambda(1) chain in J558L cells was used to immunize BALB/C mice. A total of 17 different mAbs were obtained, which recognized the rIgE heavy chain constant region. None of the mAbs reacted with monoclonal equine isotypes IgM, IgG1 (IgGa), IgG3 (IgG(T)), IgG4 (IgGb) or isolated equine light chains, IgGc and IgA from horse serum, or the native mAb B1-8delta, expressing the same heavy chain variable regions and light chains. One of the mAbs (alphaIgE-132) recognized the recombinant equine IgE, but did not recognize any protein in equine serum, i.e. native IgE. A total of 16 mAbs detected a serum protein of approximately 210,000Da on Western blots, corresponding to the expected MW of native IgE. In addition, one of the mAbs (alphaIgE-176) detected a protein of 76,000Da under reducing conditions, most likely the equine IgE heavy chain. According to binding inhibition studies, the equine IgE specific mAbs recognize at least two different epitopes of the equine IgE. In an ELISA using two anti-IgE mAbs which recognized different epitopes, no significant differences in the concentration of total serum IgE could be detected between adult Icelandic horses with IgE-mediated type I allergy (summer eczema) and healthy control animals. In Icelandic horse foals, no serum IgE could be measured 6 months post partum. All anti-IgE mAbs recognized a small population (1.3+/-0.5%) of leukocytes from adult Icelandic horses by surface immunofluorescence, but no cells could be detected in foal blood. The stained leukocytes from adult horses could be enriched by magnetic cell sorting and contained 32% basophils, 53% monocytes and/or large lymphocytes, 13% small lymphocytes and 2% eosinophils.  相似文献   
34.
A nutritional plan should be incorporated into every treatment plan of the critically ill patient. Weight loss and cachexia are the result of prevalence of catabolic processes over anabolic processes in addition to absolute or relative increased demands and decreased food intake.  相似文献   
35.
The spatial distribution of plant-available mineral nutrients in forest soils is often highly heterogeneous. To test the hypothesis that local nutrient enrichment of soil leads to increased root proliferation in the nutrient-rich soil zone, we studied the effects of nutrient enrichment on the growth and nutrient concentrations of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) roots. Three-year-old seedlings were grown for 9 months in split-root containers filled with nutrient-poor forest mineral soil, with one side supplemented with additional mineral nutrients. Root dry weight and root length in Scots pine and Norway spruce were increased in the nutrient-supplemented soil compared with the nonsupplemented side, whereas root growth in Douglas-fir was unaffected by nutrient enrichment. Of the three species examined, Norway spruce exhibited the highest root and shoot growth and the highest nutrient demand. Specific root length (m g(-1)) and the number of root tips per unit root length were not affected by local nutrient addition in any of the species. Despite increased root growth in Norway spruce and Scots pine in nutrient-supplemented soil, their root systems contained similar nutrient concentrations on both sides of the split-root container. Thus, coniferous trees may respond to local nutrient supply by increased root proliferation, but the response varies depending on the species, and may only occur when trees are nutrient deficient. As a response to local nutrient enrichment, increases in root dry matter or root length may be better indicators of pre-existing nutrient deficiencies in conifers than increases in root nutrient concentrations.  相似文献   
36.
West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNV-specific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNV encephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the three anti-IgM antibodies. The anti-IgM 1-22 mAb correctly identified all NVSL samples. Both the polyclonal antibody and monoclonal anti-IgM 2B-63 identified eight out of ten samples correctly. The three assays were then compared using serum samples from clinically healthy animals (n=33) and horses with neurological signs (n=21). High Spearman rank correlations (0.76-0.86) were found among the ELISA results. Inter-test agreements (weighted kappa) for assay interpretation resulted in strong agreement (0.95) of the results obtained by the mAbs and moderate agreements when monoclonal and polyclonal anti-IgM-based assays were compared. To determine the analytical sensitivities of anti-WNV IgM detection, serial dilutions of WNV IgM-positive serum samples were analyzed. The highest sensitivity was obtained by using the anti-IgM 1-22 mAb to capture IgM from equine serum. In conclusion, the use of monoclonal anti-IgM antibodies can improve the sensitivity of IgM detection in the acute phase of WN disease.  相似文献   
37.
To understand the effect of increased soil N supply on tree growth and nutrient uptake, three-year-old Norway spruce seedlings were grown in pots on low-nutrient mineral forest soil supplemented with N in mineral or organic form. Outdoor shaded growth conditions were used, to test the hypothesis that shaded plants are particularly susceptible to high soil N supply. Plants were harvested eleven months after planting. Shoot growth was not affected by the N supply, but N concentrations in needles and roots were increased in plants supplied with mineral N (150 or 300 mg N [kg soil]—1). Root growth was drastically reduced and root/shoot ratios were decreased in plants with higher N uptake. A high supply of mineral N to soil also decreased the concentrations of other essential elements (P, K) in the needles and thus had effects on plant growth which may impair the stress resistance of trees. Organic N in the form of keratin (150 mg N [kg soil]—1) did not influence plant growth significantly. The adverse effects of high mineral N supply were particularly pronounced under shaded conditions in comparison to results from other experiments using higher light intensity and temperature conditions.  相似文献   
38.
Background: As veterinary medicine has become more sophisticated, with greater numbers of veterinary patients receiving intensive care, more patients with an acute respiratory distress (ARDS)‐like syndrome have been recognized. Methods: A consensus definition meeting was held for the purpose of developing veterinary‐specific definitions for acute lung injury (ALI) and ARDS. Results/conclusions: Three clinically based definitions for acute lung injury and acute respiratory distress‐like syndromes occurring in veterinary patients were described. Neonatal equine respiratory distress syndrome (NERDS) was defined separately due to the specific requirement for primary developmental surfactant dysfunction and lack of an inflammatory component. Five diagnostic criteria categories were established for Veterinary ALI/ARDS (Vet ALI/ARDS) with 4 required and a fifth highly recommended criteria. A strong consensus was reached that onset of respiratory distress must have been acute and that known risk factors must be present. Additional criteria included evidence of pulmonary capillary leak with no evidence of increased pulmonary capillary pressure, evidence of inefficient gas exchange and, finally, evidence of inflammation. Some features of ALI/ARDS in the neonatal horse were recognized as unique, therefore, equine neonatal ALI/ARDS (EqNALI/EqNARDS) was similarly defined but with a graded gas exchange inefficiency table to allow for normal developmental changes in gas exchange. Use of these definitions in planning prospective studies of these problems in veterinary patients should allow for more direct comparisons of studies and clinical trials, with a larger goal of improving outcome in veterinary patients.  相似文献   
39.
Vossbrinck CR  Debrunner-Vossbrinck BA 《Folia parasitologica》2005,52(1-2):131-42; discussion 130
The Microsporidia are a group of obligate intracellular parasites, now thought to be derived fungi. Presented here is a comparative small subunit rDNA (ssrDNA) analysis of 125 species of Microsporidia (sequences obtained from GenBank). This analysis shows that groups or clades are formed based largely on habitat and host. This result is supported by comparative molecular analyses of the past decade, and indicates that structural and ultrastructural characters are unreliable for distinguishing among higher-level microsporidian taxa. Our findings indicate the presence of five major clades of Microsporidia which group according to habitat. We present three new classes of Microsporidia based on natural phylogenetic groupings as illustrated by the ssrDNA analysis: Aquasporidia, Marinosporidia and Terresporidia. The names of the proposed classes reflect the habitat of each group. The class Aquasporidia, found primarily in freshwater habitats, is a paraphyletic group consisting of three clades. The Marinosporidia are found in hosts of marine origin and the Terresporidia are primarily from terrestrial environments.  相似文献   
40.
Field studies and laboratory investigations based upon cultures, isoenzyme electrophoresis and RAPD-PCR were carried out to get a better understanding of the value of morphospecies within the genus Mesaphorura.Culturing of seven Mesaphorura species under constant as well as variable conditions provided a basis for evaluation of morphological characters, but did not yield any statistically supportable evidence that intraspecific variability reached interspecific delimitations.In enzyme tests, esterases gave the best results. The search for species-specific band patterns is, however, time and material consuming. DNA investigations using RAPD-PCR resulted in band patterns that appeared to be species specific. Nevertheless, these require further investigations.None of the studies carried out gave any conclusive evidence for invalidation of the morphologically defined species of the genus Mesaphorura.  相似文献   
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