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31.
To examine the role of longitudinal connectivity on the spatial and temporal dynamics of mountain whitefish (Prosopium williamsoni), we quantified movement and population dynamics following installation of the Landsburg Dam fishway, Cedar River, WA, USA. Mountain whitefish is widely distributed, poorly studied and not the focus of restoration. Before the fishway, mountain whitefish were not observed above the dam. Here, we focus on snorkel counts collected at reach and mesohabitat (e.g. pools) scales over 11 summers on the 20‐km above‐dam segment following restoration. A camera within the ladder provided number, size and movement timing, thereby informing on behaviour and recolonisation. Segment‐scale abundance increased following fish passage reaching an asymptote in 7 years, and mountain whitefish were detected throughout the main stem in 10 years. Annual movement through the ladder increased over time and was positively correlated with instream abundance and discharge, but negatively correlated with water temperature. About 60% of fish movements occurred in spring and early summer, potentially for foraging opportunities. Reach‐scale abundance peaked between 7 and 10 km from the dam; deep, cool (~10.6 to 11.6°C) conditions characterised these reaches. At the mesohabitat scale, mountain whitefish detection increased with depth and velocity after accounting for distance from the dam. Our results show how restoring longitudinal connectivity allowed this nontarget species to colonise newly available habitat. Their response supports the critical roles of longitudinal connectivity and environmental conditions, that manifest at different spatial scales, in dictating how freshwater fish respond to habitat disturbance.  相似文献   
32.
The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km2 grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km2 grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits.  相似文献   
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以盆花月季'仙境'为试材,采用根部浇灌方式,设置0(P0)、10 (P10)、20(P20)、30(P30)g·柱-14个磷供应水平,研究了磷水平对盆花月季'仙境'根系生长、不同器官氮磷养分吸收、叶片SPAD值以及开花品质(花朵数量、花径、花朵干质量等)的影响,以期为月季养分管理提供参考依据.结果 表明:磷不同供应水平明显改变了'仙境'的根系形态,P20和P30处理较P0和P10处理,总根长增加了81%~111%,总根表面积扩大了133%~196%,细根总长度增加了95%~119%.植株不同器官(新生叶片、新生枝条和根系)生物量和氮、磷养分积累量表现出与根系生长类似的趋势.与P0和P10处理相比,P20和P30处理单株花朵数量增加128%~206%,叶片SPAD值增加16%~21%.与对照P0相比,P10、P20和P30花径分别增加12%、19%和24%.植株总根长与总氮和总磷吸收量表现出显著的正相关关系.综上所述,盆花月季'仙境'对不同磷供应水平表现出高度的根形态可塑性,适宜的磷供应水平促进根系生长和养分吸收,提高开花数量和品质.  相似文献   
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36.
Epidermal growth factor (EGF)-like activity was measured in mares' colostrum and milk by radioreceptor assay. Milk samples were collected from 22 mares 1 or more times during early lactation. Samples of colostrum were taken after parturition and before the foal first suckled (presuckle), within 6 hours after the foal first suckled (postsuckle), and on days 1, 2, 4, and 8 of lactation. In the 5 mares from which milk samples were obtained at each sampling time, presuckle colostral mean EGF-like activity (17.8 ng/ml) was greatest (P less than 0.05). The mean values for EGF-like activity at all other sampling times were not significantly different from each other (postsuckle colostrum, 9.7 ng/ml; day 1, 9.6 ng/ml; day 2, 8.5 ng/ml; day 4, 8.0 ng/ml; day 8, 7.8 ng/ml).  相似文献   
37.
Immune system dysfunction and immunoglobulin deficiency was diagnosed in a 2-year-old horse with disseminated lymphosarcoma. Prolonged (35 days) parenteral nutrition was delivered to support the horse during a period in which immune function studies could be performed. Correction of nutritional compromise by use of parenteral nutrition did not correct the immunoglobulin deficiency, and results of lymphocyte phenotype testing did not indicate abnormal proportions of leukocytes. Lymphoblast transformation studies were suggestive of a circulating immunosuppressive factor in the horse's serum. Normal cell function was detected when the cells were stimulated in precolostral equine serum.  相似文献   
38.
Lamb carcasses (n = 278) were selected immediately after slaughter and fat thickness was measured with the SP2 Hennessy grading probe (HP) at the interface of the 12th and 13th ribs, 3.8 cm from the backbone. After a 24-h chilling period, carcasses were graded by a USDA grader and probed with the HP to obtain a fat thickness measure on the chilled carcass. One hundred sixty-five carcasses were fabricated into wholesale cuts (.64 cm of external fat trim), and 113 carcasses were fabricated into tray-ready retail cuts (.25 cm of external fat trim). Carcass weight, fat thickness (metal probe), adjusted fat thickness, hot and chilled carcass HP fat measures, as well as kidney and pelvic fat percentage and USDA yield grade, were highly correlated to cutting yield for both fabrication methods. Regression models developed to predict wholesale cut yields using HP or grader-collected measures were similar with respect to predictive accuracy. Fat thickness explained most of the variation in wholesale and tray-ready cut yields among the variables collected by the grader. Kidney and pelvic fat accounted for more of the variation in yield of wholesale cuts during stepwise regression to determine HP equations, but for predicting tray-ready yields, fat thickness taken with the HP accounted for the largest amount of variation. Equations developed to predict tray-ready retail cut yields using the HP or USDA grader-collected carcass measures were similar in the amount of variation explained. Kidney and pelvic fat percentage must be included in equations to maximize predictive accuracy when this depot site is left in carcasses.  相似文献   
39.
Osteomyelitis caused by Cryptococcus neoformans was diagnosed in a three-year-old male Irish wolfhound. The case details and radiological findings of radiolucency and periosteal reaction of the left third metatarsal bone had lead to an initial diagnosis of a malignant bone tumour. Biopsy revealed a fungal granuloma and culture identified the causal organism. A four month course of ketaconazole was instigated and the lameness resolved. Twelve months after the end of treatment there was no recurrence of the problem.  相似文献   
40.
Findings are presented on the precision of a clinical biochemistry analyser designed specifically for veterinary use. Twenty biochemical analytes have been examined in detail for variation within and between runs. The results indicate that the analyser can provide high precision for all the analytes with the possible exception of calcium, and suggest that the instrument can be used with confidence in the practice laboratory to aid diagnosis and to monitor biochemical changes in animals receiving treatment.  相似文献   
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