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61.
Whitney MS Schwan TG Sultemeier KB McDonald PS Brillhart MN 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(2):212-216
Spirochetemia was diagnosed in 2 Siberian Huskies and a Rottweiler from the northwestern region of Texas between June 1999 and October 2001. Clinical findings were nonspecific; tick exposure was documented in 2 of the dogs. Hematologic abnormalities included anemia (n=2), neutrophilia (n=2, including 1 with a left shift), lymphopenia (n=3), eosinopenia (n=3), and thrombocytopenia (n=2). One anemic dog had a positive Coombs' test. In 1 dog, Western blot analysis of serum yielded multiple positive bands with B turicatae lysate, indicating the spirochetemia most likely was due to B turicatae infection. In 2 dogs, spirochetes were cultured from the blood and identified using DNA analysis as Borrelia turicatae; 1 of these dogs also was seropositive for Ehrlichia canis and B burgdorferi. In 2 cases, spirochetemia was more prominent in blood smears prepared immediately after sample collection than in smears prepared from EDTA blood. Two dogs recovered with doxycycline treatment; 1 dog declined clinically despite treatment and was euthanized. B turicatae is the agent of tick-borne (endemic) relapsing fever in humans and is distinct from B burgdorferi, the agent of Lyme disease; however, serologic cross-reactivity may occur. B turicatae is transmitted by the soft tick, Ornithodoros turicata, and infection should be considered in dogs with spirochetemia and possible exposure to the tick vector. 相似文献
62.
OBJECTIVE: To determine the effect of meperidine administered prior to anesthesia on the incidence of vomiting before, and gastroesophageal reflux (GER) and regurgitation during, the subsequent period of anesthesia in dogs. STUDY DESIGN: Randomized, controlled trial. ANIMALS: A total of 60 healthy dogs, 4.3 +/- 2.3 years old, and weighing 35.5 +/- 13.1 kg. METHODS: Dogs were admitted to the study if they were healthy, had no history of vomiting, and were scheduled to undergo elective orthopedic surgery. The anesthetic protocol used was standardized to include thiopental and isoflurane in oxygen. Dogs were randomly selected to receive one of the following pre-medications: morphine (0.66 mg kg(-1) IM) with acepromazine (0.044 mg kg(-1) IM), meperidine (8.8 mg kg(-1) IM) with acepromazine (0.044 mg kg(-1) IM) or meperidine alone (8.8 mg kg(-1) IM). A sensor-tipped catheter was placed to measure esophageal pH during anesthesia. Gastro-esophageal reflux was judged to have occurred if there was a decrease in esophageal pH below four or an increase above 7.5. RESULTS: No dogs vomited after the administration of meperidine, but 50% of dogs vomited after the administration of morphine. When compared with morphine, treatment with meperidine alone or combined with acepromazine before anesthesia was associated with a 55% and 27% reduction in absolute risk of developing GER, respectively. Dogs receiving meperidine alone were significantly less sedate than other dogs in the study, and required more thiopental to induce anesthesia. Arterial blood pressure and heart rate were not significantly different between groups at the start of the measurement period. Cutaneous erythema and swelling were evident in four dogs receiving meperidine. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of meperidine to healthy dogs prior to anesthesia was not associated with vomiting and tended to reduce the occurrence of GER, but produced less sedation when compared with morphine. Meperidine is not a useful addition to the anesthetic protocol if prevention of GER is desired. 相似文献
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64.
Quanqi Zhang Haiyang Yu Aimee Howe Whitney Chandler Standish K. Allen Jr 《Aquaculture Research》2010,41(11):1658-1667
Triploid oyster induction has been very successful. However, during field culture, a certain proportion of triploids apparently loses one set of chromosomes, ‘reverting’ to diploid–triploid mosaics. The revertants will lose their aquaculture advantages due to the recovery of reproductive ability. Mitotic chromosomes were observed in mosaics of Crassostrea gigas and Crassostrea Ariakensis to elucidate the cytogenetic mechanism of reversion. Most individuals showed a modal number of 30 in triploid cells and varying numbers of chromosomes in other cells. From all 15 mosaics of C. gigas and 16 mosaics of C. ariakensis individuals, high proportions of aneuploid cells with various numbers of chromosomes were observed. Most of the aneuploid cells were hypotriploid cells with 26–29 chromosomes. Notably, in 10 out of 15 C. gigas and 9 out of 16 C. ariakensis, some cells consisted of 20–26 well‐spread chromosomes and 3–10 chromosome ‘clumps’. Individuals with more chromosome clumps tended to have higher percentages of hypotriploid cells. The correlation between these two categories of cells was significant (P<0.05) in C. gigas and highly significant (P<0.01) in C. ariakensis. Thus, we conclude that some chromosomes are eliminated during mitotic divisions because they clump together and are thus unable to undergo normal segregation. 相似文献
65.
66.
Municipal annexation is the most common form of local government boundary change and can have profound impacts on the annexing municipality as well as the area being annexed. While urban scholars have often touted the economic benefits of annexation for municipalities, little research has been conducted on the effect of annexation type on the economic well‐being of a municipality. Do voluntary annexations result in a larger economic windfall for annexing municipalities? Do involuntary annexations cost more? This study examined more than 6,000 annexations conducted by North Carolina municipalities between 1990 and 2000 in order to explore the impact annexation methodology had on municipal fiscal health. The results reveal that during the study period annexation resulted in a decrease in municipal fiscal health for North Carolina municipalities and that involuntary annexation had a particularly detrimental effect. This finding contradicts much of the previous research on the economic benefits of annexation for municipalities. 相似文献
67.
Evaluation of angler reporting accuracy in an off‐site survey to estimate statewide steelhead harvest
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J. L. McCormick D. Whitney D. J. Schill M. C. Quist 《Fisheries Management and Ecology》2015,22(2):134-142
Accuracy of angler‐reported data on steelhead, Oncorhynchus mykiss (Walbaum), harvest in Idaho, USA, was quantified by comparing data recorded on angler harvest permits to the numbers that the same group of anglers reported in an off‐site survey. Anglers could respond to the off‐site survey using mail or Internet; if they did not respond using these methods, they were called on the telephone. A majority of anglers responded through the mail, and the probability of responding by Internet decreased with increasing age of the respondent. The actual number of steelhead harvested did not appear to influence the response type. Anglers in the autumn 2012 survey overreported harvest by 24%, whereas anglers in the spring 2013 survey under‐reported steelhead harvest by 16%. The direction of reporting bias may have been a function of actual harvest, where anglers harvested on average 2.6 times more fish during the spring fishery than the autumn. Reporting bias that is a function of actual harvest can have substantial management and conservation implications because the fishery will be perceived to be performing better at lower harvest rates and worse when harvest rates are higher. Thus, these findings warrant consideration when designing surveys and evaluating management actions. 相似文献
68.
Richard B. Chandler David I. King Carlin C. Chandler 《Forest Ecology and Management》2009,258(7):1669-1676
Many shrubland bird species are declining in eastern North America and as a result forest managers have used a variety of techniques to provide breeding habitat for these species. The maintenance of permanent “wildlife openings” using prescribed burns or mechanical treatments is a widely used approach for providing habitat for these species, but there have been no studies of the effects of treatment regime on bird abundance and nest survival in managed wildlife openings. We studied shrubland birds in wildlife openings on the White Mountain National Forest (WMNF) in New Hampshire and Maine, USA, during 2003 and 2004. We analyzed bird abundance and nest survival in relation to treatment type (burned versus mowed), treatment frequency, time since treatment, and patch area. We found that wildlife openings provided habitat for shrubland birds that are not present in mature forest. There was relatively modest support for models of focal bird species abundance as a function of treatment regime variables, despite pronounced effects of treatment on habitat conditions. This probably was attributable to the combined effects of complex site histories and bird site fidelity. Overall nest success (52%) was comparable to other types of early-successional habitats in the region, but there were few supported relationships between nest survival and treatment variables. We conclude that wildlife openings provide quality habitat for shrubland birds of high conservation interest as long as managers ensure treatment intervals are long enough to permit the development of woody vegetation characteristic of the later stages of this sere. Also, wildlife openings should be large enough to accommodate the territory sizes of all target species, which was ≥1.2 ha in this study. 相似文献
69.
Cory W. Whitney Eike Luedeling John R. S. Tabuti Antonia Nyamukuru Oliver Hensel Jens Gebauer Katja Kehlenbeck 《Agriculture and Human Values》2018,35(2):399-424
Homegardens are traditional food systems that have been adapted over generations to fit local cultural and ecological conditions. They provide a year-round diversity of nutritious foods for smallholder farming communities in many regions of the tropics and subtropics. In southwestern Uganda, homegardens are the primary source of food, providing a diverse diet for rural marginalized poor. However, national agricultural development plans as well as economic and social pressures threaten the functioning of these homegardens. The implications of these threats are difficult to evaluate, because the structure and functions of the homegardens are not well understood. The aim of the study was to identify patterns and influencing factors in the diversity of homegardens by documenting the floristic diversity and its interactions with spatial, environmental and socio-economic factors. A geographically and socially focused assessment of floristic diversity in 102 randomly selected homegardens in three districts of southwest Uganda was conducted along a deforestation gradient following a human ecology conceptual framework and testing multiple quantitative hypotheses regarding the above mentioned factors. A merged mixed-method approach was followed to provide context and feedback regarding quantitative findings. Results show a high total richness of 209 (mean 26.8 per homegarden) crop species (excluding weeds and ornamentals) dominated by food species, which constituted 96 percent of individuals and 44 percent of all species. Forest-edge homegardens maintained higher plant diversity compared to homegardens in deforested areas and near degraded wetlands. Multiple linear regression models indicated elevation, location, homegarden size, distance to market, additional land ownership (outside the homegarden) and livestock ownership as significant predictors of crop diversity. Cluster analysis of species densities revealed four garden types: ‘diverse tree gardens’, ‘small forest-edge gardens’, ‘large, old, species-rich gardens’, and ‘large, annual-dominated herb gardens’, with 98% correct classification. Location, elevation, and garden size were also important determinants in the cluster assignment. We conclude that the diversity of the studied homegardens may be changing as part of adaptive traditional practices and in response to external drivers. The identified patterns illustrate the importance of homegardens for rural livelihoods and may offer some ways to support farmers to maintain these systems as relevant mechanisms for development in Uganda. 相似文献
70.
N. Gosman† Srinivasachary A. Steed E. Chandler M. Thomsett P. Nicholson 《Plant pathology》2010,59(1):147-157
A series of experiments was conducted to determine whether type I resistance (resistance to initial infection) to fusarium head blight (FHB) in wheat could be assessed using fungal species/isolates that do not produce deoxynivalenol (DON), a mycotoxin critical to the spread of Fusarium graminearum in the wheat spike. It was shown that, while the non-toxin-producing species Microdochium nivale and M. majus could infect following spray inoculation of wheat spikes, they were unable to spread within the spike following point inoculation. However, although these species might reveal type I resistance, they are not highly pathogenic towards wheat. A nivalenol (NIV)-producing isolate of F. graminearum caused high levels of disease following spray inoculation, but spread only very slowly within the spike and rarely induced bleaching above the point of inoculation. It is proposed that spray inoculation with an appropriate, aggressive, non-DON-producing FHB pathogen may be used to characterize type I resistance to complement point inoculation with a DON-producing isolate to assess type II resistance (resistance to spread within the spike). 相似文献