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101.
102.
A 4-year-old Siberian Husky dog was treated with brown snake antivenom by his regular veterinarian after a witnessed episode of brown snake envenomation. The dog was discharged 5 hours post presentation despite an ongoing coagulopathy. The dog was presented to the emergency centre 2 hours later because the owner believed the dog to be in pain. Initial examination revealed an ambulatory but neurologically normal patient with thoracolumbar pain and laboratory evidence of a coagulopathy. Despite correction of the coagulopathy, the signs progressed to bilateral hind limb paresis after approximately 3 hours of hospitalisation, and continued to deteriorate over the next 56 hours to loss of deep pain perception in the right hind limb. Computed tomography imaging identified the presence of an extradural haematoma which was subsequently removed via a hemilaminectomy. Surgical decompression was successful in treating the spinal compression and the dog recovered with minimal complications. To our knowledge this is the first report of extradural haematoma secondary to coagulopathy induced by brown snake envenomation.  相似文献   
103.
Three dogs were presented with a history of oral administration of a topical endectocide containing imidacloprid and moxidectin. They were diagnosed with imidacloprid and moxidectin intoxication, having ingested doses ranging from 7.5 to 1.4 mg/kg of imidacloprid and 1.9 to 2.8 mg/kg of moxidectin. The three dogs were affected to different degrees of severity, but all displayed signs of ataxia, generalised muscle tremors, paresis, hypersalivation and disorientation. Temporary blindness occurred in two cases. The three dogs were tested for the presence of the multi-drug resistance 1 gene deletion, which can cause an increased sensitivity to the toxic effects of moxidectin, and were found to be negative. Treatment included gastrointestinal decontamination, intravenous fluid therapy and benzodiazepines to control muscle tremors. All three dogs made a complete recovery within 48 h of ingestion.  相似文献   
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105.
Continuous stocking with sheep at high stocking rates may reduce the content of white clover (Trifolium repens) in mixed grass-clover swards. The present experiment was carried out to investigate the effects on sward production and composition of resting a perennial ryegrass (Lolium perenne)- white clover sward from grazing and taking a cut for conservation. Swards were set-stocked with 25 and 45 yearling wethers ha?1 either throughout a grazing season, or on swards that were rested for a 6-week period and then cut in early, mid- or late season. In an additional treatment swards were cut only and not grazed. Net herbage accumulation was higher at the lower of the two stocking rates and was marginally increased by the inclusion of a rest period at the high but not the low stocking rate. Clover content was higher at the lower stocking rate and was increased by the inclusion of a rest period by 30% at 45 sheep ha?1and by 11% at 25 sheep ha?1 The effect was most marked at the end of the rest period before cutting. When rested from grazing the tiller density of ryegrass decreased although tiller length increased, and clover stolon length, petiole length and leaflet diameter increased though leaf and node number per unit length of stolon decreased; the reverse applied when the sward was returned to grazing after cutting. At the high stocking rate, rest periods in mid-season or later maintained the greatest clover content and marginally increased total net herbage accumulation. At the low stocking rate the timing of the rest period had no significant effect on total net herbage accumulation or on clover content. These results show that the combination of grazing and cutting is of benefit where the stocking rate is high enough to threaten clover survival and limit sheep performance. However, at such a stocking rate, feed reserves are at a minimum throughout the grazing season and so opportunities for resting the sward are probably low.  相似文献   
106.
Perennial ryegrass was conserved by ensiling, or by dehydration, grinding and pelleting. the two resultant feeds were given ad lib. to wether sheep, either separately or in different proportions. Pellets were consumed in greater quantities than the silage, but were lower in digestibility. There was a rectilinear relationship between the percentage of pellets in the ration consumed and organic-matter digestibility, but a curvilinear relationship between the percentage of pellets and organic-matter intake. Silage intake was little affected by the feeding of pellets until more than 40% of the ration consisted of pellets. The increase in total intake with an increase in pellets above 60% was small, with the result that intake of digestible organic matter was highest when 65% pellets was fed. the results suggest that dried-grass pellets may be a useful supplement for silage rations.  相似文献   
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108.
我国热带地区具有高温多雨、雨量分布不均匀且多暴雨的特点,容易引起水土流失,土壤有机质分解快,养分淋溶流失强烈,因此热带地区的红壤和砖红壤的有机质和速效养分含量都很低。热带经济林木和果园间种绿肥覆盖作物可以保持水土,增进地力,促使主作物速生高产[1,2],而建立牧草基地以发展畜牧业和种植绿肥是增加优质有机肥料来源的有效途径。这样才有可能增施大量有机肥料,不断提高土壤肥力,保证农林作物稳产高产。  相似文献   
109.
The increasing global demand for food production, often causing excessive use of chemical fertilizers, has led to the deterioration of soil health. Immediate action is required to restore soil health in a sustainable manner. This review advocates switching to use of organic matter(manure and compost) that contains vital nutrients for plant growth and helps restore soil health. Humic substances(HSs), derived from degraded plant remains and found ubiquitously in nature,are an important source of o...  相似文献   
110.
The productivity and response to fertilizer nitrogen (N) was measured in herb-rich wetland hay meadows within a Site of Special Scientific Interest (SSSI) in Somerset, UK. Output from hay cut after 1 July each year and from beef production at aftermath grazing was measured over a total of 4 years.
Total utilized metabolizable energy (UME) output averaged from 40·6 GJ ha−1 year−1 without fertilizers to 61·7GJha−1 at 200kgNha−1 (N-200), the highest rate used, with about two-thirds of this output from hay. N response was markedly curvilinear above about 50kgN ha−1, but data from a concurrent experiment suggested that the comparatively low replacement rates of P and K applied were limiting at higher N rates. When hay cutting was delayed until early August in a wet year, yield response to N was lost because fertilized swards had passed a peak in yield several weeks before harvest.
Compared with other published data, the results suggest that output and response to N is not constrained by the diversity of the flora or the damp conditions. The data will help to estimate the financial implications for farmers of restricted or zero fertilizer use within SSSIs and the wider Environmentally Sensitive Areas.  相似文献   
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