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1.
SUMMARY: Confinement of horses with their heads elevated for periods up to 24 hours was used to evaluate the extent and the effects of bacterial contamination of the equine lower respiratory tract. Significant (P < 0.05) increases in bacterial numbers (up to 109 colony forming units/mL in transtracheal aspirate derived samples) occurred within 6 or 12 hours in most horses. Pasteurella/Actinobacillus spp and Streptococcus spp were most commonly isolated. Lowering of the head for 30 minutes every 6 hours to facilitate postural drainage did not prevent multiplication of organisms to levels equivalent to those achieved by horses where the head was elevated for 24 hours. When horses were released from confinement and heads were no longer maintained in an elevated position, clearance of accumulated secretions and bacteria occurred within 8 to 12 hours. Thus, confinement with the head elevated resulted in significant bacterial contamination and multiplication within the lower respiratory tract during a period often encountered in routine management procedures, such as transportation. The clearance of accumulated secretions occurred over a prolonged period after release from such confinement.  相似文献   
2.
The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   
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Comparative gear tows were conducted during the summers of 1987–1990 in the Gulf of Alaska. Efficiencies of four types of ichthyoplankton sampling gear were compared with respect to total catch and size distribution of larval fish. Fish were sampled using the bongo net (333 and 505 μm mesh), 1 m Tucker net, 3 m Tucker net and the Methot frame net. Results indicate that the bongo and the 1 m Tucker nets caught similar numbers and size distribution of fish. The larger 3 m Tucker and Method frame nets caught a larger size class of fish but a smaller total catch. Although there was a slightly significant diel difference in total catch detected in the smaller nets, no diel differences in size distribution of fish caught were detected for any of the nets.  相似文献   
5.
High quality, agricultural nutrient distribution maps are necessary for precision management, but depend on initial soil sample analyses and interpolation techniques. To examine the methodologies for and explore the capability of interpolating soil properties based on neural network ensemble residual kriging, a silage field at Hayes, Northern Ireland, UK, was selected for this study with all samples being split into independent training and validation data sets. The training data set, comprised of five soil properties: soil pH, soil available P, soil available K, soil available Mg and soil available S,was modeled for spatial variability using 1) neural network ensemble residual kriging, 2) neural network ensemble and 3) kriging with their accuracies being estimated by means of the validation data sets. Ordinary kriging of the residuals provided accurate local estimates, while final estimates were produced as a sum of the artificial neural network (ANN) ensemble estimates and the ordinary kriging estimates of the residuals. Compared to kriging and neural network ensemble,the neural network ensemble residual kriging achieved better or similar accuracy for predicting and estimating contour maps. Thus, the results demonstrated that ANN ensemble residual kriging was an efficient alternative to the conventional geo-statistical models that were usually used for interpolation of a data set in the soil science area.  相似文献   
6.
基于冠层多光谱数据预测水稻氮素营养状况   总被引:5,自引:0,他引:5  
A soil batch experiment was conducted to investigate both separate and compound effects of three types of surfactants: anionic dodecylbenzene sulfonic acid sodiumsalt (DBSS), cationic cetyltrimethylammonium bromide (CTAB), and nonionic nonyl phenol polyethyleneoxy ether (TX-100), as well as ethylenediaminetetraacetic acid (EDTA) on cadmium solubility, sorption kinetics, and sorption-desorption behavior in purple soil. The results indicated that both individual application of the three types of surfactants and surfactants combined with EDTA could stimulate Cd extraction from the soil with a general effectiveness ranking of EDTA/TX-100 〉 EDTA/DBSS 〉 EDTA/CTAB 〉 EDTA 〉 TX-100 〉 DBSS 〉 CTAB. Further study showed that the compound application of surfactants and EDTA had stronger (P 〈 0.05) effects on Cd solubility than those added individually. The application of surfactants and EDTA to purple soil (P 〈 0.05) decreased the proportion of Cd sorbed, while their effectiveness ranking was similar to that of enhanced solubilization. The sorption kinetics of Cd in purple soil was best described by the double-constant equation, while the Freundlich equation gave an excellent fit to the sorption isotherm curves. Therefore, surfactant-enhanced remediation of Cd contaminated soil is feasible and further research should be conducted.  相似文献   
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Maiden heifers and lactating cows of known ovarian status and of several breeds were treated with a synthetic prostaglandin, cloprostenol, or a synthetic progestagen, norgestomet, at the start of an artificial insemination (AI) program. Animals in the cloprostenol treatment received 2 injections 10 days apart. Over the next 26 days those animals that showed oestrous behaviour were inseminated. Synchronisation rates and calving rates to insemination over the first 7 days were calculated. Those in the norgestomet treatment received an implant of norgestomet plus an injection of norgestomet and oestradiol valerate. The implant was removed 10 days later and the animals were given an injection of pregnant mare serum gonadotrophin (PMSG). They were inseminated at 48 h (maiden heifers) or 56 h (lactating cows) after implant removal. Calving rates to fixed-time insemination were recorded. After completion of the AI program the animals in both treatments were joined with bulls. Overall calving rates (AI plus bulls) were calculated. By day 7 of the program, 82% of the maiden heifers and 76% of the lactating cows in the cloprostenol treatment had been detected in oestrus. By day 21 the respective figures were 99% and 81% Norgestomet treatment had an immediate and a prolonged effect on ovarian activity in those females classified as having inactive ovaries at the start of the AI program. Calving rates of those females to fixed-time AI and overall were similar to those of the females with active ovaries in both treatments. Their calving rates to fixed-time insemination, and overall calving rates for the lactating females, were significantly higher than the corresponding values of their contemporaries treated with cloprostenol and inseminated on observed oestrus over 7 days. For those females classified as having active ovaries at the start of the AI program, calving rates to first insemination and overall were similar for both treatments. Overall calving rates of lactating cows of each breed were, with one exception, higher in the norgestomet treatment than in the cloprostenol treatment. Although norgestomet treatment was more expensive than cloprostenol treatment, the advantage in calf crop resulted in an overall monetary advantage to the norgestomet treatment.  相似文献   
9.
Wound closure utilizing tension-relieving incisions located in the skin adjacent to the wound of horses was evaluated in three experiments. Healing of lower limb wounds was compared in four treatment groups; wounds sutured under tension, wounds sutured with 7 mm and 10 mm tension relieving incisions, and unsutured controls. The wounds sutured using 10 mm tension relieving incisions healed significantly faster than the other three groups (p > 0.05). The mesh expansion technique was further evaluated in four-week-old granulating wounds. The technique was found to be unsuccessful because the tension relieving incisions that were used were too small and postoperative support was inadequate. The technique was evaluated in two clinical patients, both of which had large metatarsal lacerations. Tension relieving incisions of approximately 15 mm were made and full leg walking bar casts were applied. Both wounds had healed almost completely on removal of the casts four weeks postoperatively.  相似文献   
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