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71.
Brook RK Kutz SJ Millins C Veitch AM Elkin BT Leighton T 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(10):1115-1122
Domestic animal health services are supplied to communities in Canada's Northwest Territories (NT) in diverse ways, including private veterinary practices in 2 of 33 communities, and by mail-order, fly-in, free clinics, and a government-coordinated lay vaccinator program in some of the other 31 communities. We evaluated delivery, needs, and potential uptake of domestic animal health services in the Sahtu Settlement Area, NT by offering free clinics for 225 dogs in 2008 and 2009; and administered questionnaires to 42 dog owners and 67 students in 2008. Owners indicated that 20% of dogs were neutered, 37% had had rabies vaccinations, and 29% had been dewormed. Physical examination of dogs demonstrated that 54% were "thin" and 4% were "emaciated." Owners and youth showed a range of attitudes toward dogs and supported improved domestic animal health services. Future services need to build on existing programs and collaborate with communities to ensure relevance, ownership, and sustainability. 相似文献
72.
Restoration of grasslands dominated by tall fescue (Schedonorus phoenix [Scop.] Holub) to native tallgrass prairie usually requires burning, herbicides, or reseeding. We tested seasonal grazing by livestock in winter, combined with cessation of fertilization, as a restoration tool for modifying the competitive dynamics among herbaceous plants to restore tallgrass prairie communities in southeastern Kansas. In 2004–2005, we compared responses of grassland plants and birds across a chronosequence of pastures that were winter-grazed from 1 yr to 5 yr. We compared winter-grazed pastures to pastures grazed year-round and to local native prairie remnants as starting and endpoints for restoration, respectively. Abundance of native warm-season grasses increased from 2% to 3% mean relative frequency in pastures grazed year-round to 18% to 30% in winter-grazed pastures, and increased with duration of winter-grazing. Native warm-season grasses accounted for 1–6% of total live aboveground biomass in pastures grazed year-round, 1–34% in winter-grazed pastures, and 31–34% in native prairie remnants. Tall fescue abundance and biomass were similar among grazing treatments, with a trend for tall fescue to be less dominant in winter-grazed pastures. Tall fescue made up 9–40% of total aboveground biomass in year-round grazed pastures and 10–25% in winter-grazed pastures. Grassland birds showed variable responses to winter-grazing. Dickcissels (Spiza americana) and Henslow’s sparrows (Ammodramus henslowii) were more abundant in winter-grazed pastures, whereas eastern meadowlarks (Sturnella magna) and grasshopper sparrows (A. savannarum) had similar abundance in pastures grazed year-round and during winter. Winter-grazing of pastures dominated by tall fescue combined with suspension of nitrogen fertilization could be an effective restoration technique that allows use of prairie rangeland while improving habitat for sensitive grassland birds. 相似文献
73.
Isabelle Ann Kagan PhD Brett H. Kirch DVM PhD Craig D. Thatcher DVM PhD Chris D. Teutsch PhD François Elvinger Dr Med Vet PhD Dare M. Shepherd BS Scott Pleasant DVM MS 《Journal of Equine Veterinary Science》2011,31(9):521-529
Seasonal and diurnal patterns of sugar accumulation in bermudagrass (Cynodon dactylon) pastures were monitored to evaluate risk factors for pasture-associated laminitis of ponies and horses. Bermudagrass was collected from four plots in the morning and afternoon on a weekly basis, from mid-July until late August. Tissue was air-dried to simulate hay, or frozen to retain the sugar profiles of fresh pasture. Samples were analyzed colorimetrically for total water-soluble and ethanol-soluble carbohydrates, and electrochemically for starch. In addition, sugars were separated and quantified by high-performance liquid chromatography coupled to pulsed amperometric detection. The dominant sugars in extracts were glucose, fructose, and sucrose. Some minor peaks, corresponding to tri- and tetrasaccharides, were also detected in some extracts. Starch increased over time in fresh and dried tissue, and concentrations varied diurnally in fresh, but not in dried tissue (P = .021). Sucrose in dried tissue decreased and then increased, with higher concentrations than in fresh tissue on all sampling dates (P = .024). Glucose and fructose exhibited diurnal variation on one and two dates, respectively (P = .034 and .0028, respectively). These results reveal trends in carbohydrate concentrations and profiles that may help to evaluate the likelihood of equine laminitis outbreaks on bermudagrass. 相似文献
74.
Eberts MD Vissotto de Paiva Diniz PP Beall MJ Stillman BA Chandrashekar R Breitschwerdt EB 《Journal of the American Animal Hospital Association》2011,47(6):e86-e94
Eighteen clinically ill dogs, naturally infected with Anaplasma phagocytophilum, were examined at a veterinary practice in Baxter, Minnesota. A clinical examination, complete blood cell count, enzyme- linked immunosorbent assay (ELISA) for A phagocytophilum, Borrelia burgdorferi, and Ehrlichia canis antibodies and Dirofilaria immitis antigen, and a polymerase chain reaction test for A phagocytophilum DNA were obtained for all dogs. Physical examination findings included fever, arthropathy, lymphadenopathy, epistaxis, acute gastritis, cervical hyperpathia, and central nervous system dysfunction. Complete blood cell count abnormalities included thrombocytopenia, morulae in neutrophils, anemia, leukopenia, eosinopenia, lymphopenia, and monocytosis. Seroreactivity to A phagocytophilum was found in 61%, B burgdorferi antibodies in 17%, and D immitis antigen in 5% of the dogs. Fever, arthropathy, neurologic dysfunction, and epistaxis are clinical syndromes that can be associated with A phagocytophilum infection. Treatment with doxycycline resulted in rapid resolution of clinical signs in all dogs. 相似文献
75.
Isabelle A. Kagan Brett H. Kirch Craig D. Thatcher James R. Strickland Chris D. Teutsch François Elvinger R. Scott Pleasant 《Journal of Equine Veterinary Science》2011,31(8):488-497
Seasonal and diurnal changes in water-soluble carbohydrates (WSC) and ethanol-soluble carbohydrates (ESC), as well as in chromatographic profiles of the sugars comprising these categories, were studied in orchardgrass pastures at one location in the Piedmont region of Virginia. Grass from four experimental plots was sampled weekly in the morning and afternoon over an 8-week period (early to late spring). Tissue was air-dried to simulate hay, or frozen to preserve the sugar profiles of fresh pasture. WSC and ESC were assayed colorimetrically. To profile sugars, boiled-water extracts were separated by high-performance liquid chromatography coupled to pulsed amperometric detection. Fructan, glucose, fructose, and sucrose were quantified by high-performance liquid chromatography. All sugar concentrations were highest in the early spring in both fresh and dried tissue. Fructan chain length was highest in early spring as well. Significant diurnal differences were observed for WSC and fructan, on some dates (P < .0001 and P = .024, respectively), and for ESC, glucose, and sucrose averaged over the entire period (P = .0002, .004, and <.0001, respectively). Sucrose was barely detectable in fresh tissue but reached 1.6% to 12% dry matter in dried tissue. These results demonstrate changes in orchardgrass carbohydrates over a season, within a day, and between dried and fresh herbage. Understanding these changes may be helpful in the management of horses with a history of insulin resistance and laminitis. 相似文献
76.
77.
Blessing Mabate Chantal Dsire Daub Samkelo Malgas Adrienne Lesley Edkins Brett Ivan Pletschke 《Marine drugs》2021,19(1)
Fucoidans are complex polysaccharides derived from brown seaweeds which consist of considerable proportions of L-fucose and other monosaccharides, and sulphated ester residues. The search for novel and natural bioproduct drugs (due to toxicity issues associated with chemotherapeutics) has led to the extensive study of fucoidan due to reports of it having several bioactive characteristics. Among other fucoidan bioactivities, antidiabetic and anticancer properties have received the most research attention in the past decade. However, the elucidation of the fucoidan structure and its biological activity is still vague. In addition, research has suggested that there is a link between diabetes and cancer; however, limited data exist where dual chemotherapeutic efforts are elucidated. This review provides an overview of glucose metabolism, which is the central process involved in the progression of both diseases. We also highlight potential therapeutic targets and show the relevance of fucoidan and its derivatives as a candidate for both cancer and diabetes therapy. 相似文献
78.
Recent reports have shown that some of the immunological aspects of Q fever, a rickettsiosis caused by Coxiella burnetii, could be related to self-antigen responses. The aim of this study was to determine the specificity of the autoantibody response of patients with acute and chronic Coxiella infections. Smooth muscle and cardiac muscle-specific autoantibodies were observed in significant percentages in acutely or chronically affected Q fever patients when compared to healthy volunteers. Moreover, the incidence of cardiac muscle-specific autoantibody was significantly higher among chronically ill patients compared to acutely ill patients. Moreover, a band of 50 kD of a HeLa extract was detected in most of the sera of individuals with chronic infections and previous sequence analysis suggests that this antigen presents a high degree of homology with the human actin elongation factor 1 alpha. Further research would be necessary to confirm if antibodies to human cytoskeletal proteins could be of clinical importance in chronically infected Q fever patients. 相似文献
79.
Russell S. Crosbie Brett Wilson Justin D. Hughes Christopher McCulloch Warren McG. King 《Agricultural Water Management》2008,95(3):211-223
Planting trees has been proposed as part of the solution to dryland salinity in Australia. The best location in the landscape and the spatial arrangement of trees however, is difficult to determine. This paper presents a case study of a field experiment that compared the water use of tree belts with that of pastures in recharge and discharge areas of a first order catchment in the Central West of NSW, Australia.The recharge tree belt and both pasture sites used very similar amounts of water but the discharge tree belt used double the water of the other three land uses by accessing groundwater. The discharge tree belt operated in an energy-limited environment, transpiring at a rate equivalent to atmospheric demand whereas the other three land uses were all water-limited. From a land management point of view, the establishment of more trees on the discharge site would have the biggest impact on reducing saline discharge and the least impact on the agricultural operations. 相似文献
80.
We describe the proteomic identification of two pathogenesis-related group 5 (PR-5) proteins, an acidic thaumatin-like protein (TLP) and a basic TLP isolated from the pollination drop of hybrid yew (Taxus x media Rehder). The basic TLP (TxmTLPb) was the most abundant protein in the yew pollination drop based on protein spot size after two-dimensional electrophoresis. The acidic TLP (TxmTLPa) is also a major protein component of the yew ovular secretion and appears to be encoded by a number of mRNAs transcribed from a TLP gene family that has undergone limited sequence divergence. We have sequenced five acidic TLP-encoding cDNAs (TxmTLPa-1,2,3,4 and 5) isolated from the yew ovule that vary from each other by no more than five out of 233 amino acid residues in their predicted protein sequences. All of the cDNA variants encode TLPs possessing the 16 conserved cysteine residues and five charged amino acid side chains associated with antifungal activity. Amplification of genomic DNA with TxmTLPa primers indicated that at least 11 acidic TLPs with highly similar amino acid sequences may be expressed in yew tissues. Antibodies against TLPs confirmed the identity of TxmTLPa and TxmTLPb in the yew pollination drop and detected TLPs in the ovular secretions of four other species from three other conifer families. Our results suggest that TLPs are a conserved component of conifer ovular secretions and are involved in broad spectrum pathogen defence of ovules. 相似文献