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191.
AIM: To estimate incidence risk, cumulative mortality and case fatality rate within herds affected by bovine anaemia associated with Theileria orientalis infection (TABA), in New Zealand during the early phase of the epidemic (August 2012–September 2013).

METHODS: A mixed methods approach was utilised to integrate data from various sources, including a detailed questionnaire carried out on 18 dairy farms which had experienced cases of TABA; a brief telephone survey of an additional 139 case farms; and data extracted from a Ministry for Primary Industries database for a further 42 case farms. The subsequent analysis determined incidence risk, cumulative mortality and case fatality rates for beef and dairy herds.

RESULTS: Data were analysed from 196/263 (74%) known case farms at the date of closing the questionnaires. These farms contained 99,505 cattle; 2,847 animals were reported with clinical disease, and a further 590 animals were recorded as having died from TABA. The within-herd incidence risk, cumulative mortality and case fatality rate were consistent between the three data sources, did not differ between beef and dairy herds, and were estimated to be 0.97 (inter-quartile range (IQR) 0.36–2.07)%, 0.23 (IQR 0.00–0.66)% and 16.67 (IQR 0.00–33.33)%, respectively. There was substantial variability in the level of impact, with 22 farms severely affected (incidence risk >5% and cumulative mortality >5%).

CONCLUSIONS: The mixed methods approach was effective in dealing with the disparate data sources. The inclusion of the majority of farms known to be affected at the time the questionnaires were performed implies that the information is likely to be representative. The collective outputs of the analyses represent the best estimate available of within-herd measures of disease frequency in the early phase of the epidemic in New Zealand. The limitations of the data imply that their primary application may be to inform the design of subsequent structured observational field studies.

CLINICAL RELEVANCE: The results of this study provide information on the impact of TABA on cattle farms during the emergence and early spread of the disease, as well as for generating hypotheses on causal mechanisms and risk factors that may influence the course of disease.  相似文献   

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CONTENT OF INOSITOL PENTA- AND HEXAPHOSPHATES IN SOME CANADIAN SOILS   总被引:2,自引:0,他引:2  
The combined amounts of inositol penta- and hexaphosphates in a number of Canadian soils of differing origin have been measured. The esters were precipitated as barium salts from alkali extracts and purified by anion-exchange chromatography; their identity was confirmed by paper-partition chromatography. An alternative method involving precipitation of the esters as ferric salts in acid medium was found to give much lower values, probably because of incomplete precipitation. Values for eighteen surface soils ranged from 20 to 71 and for twelve subsoils from 18 to 43 ppm P. The amounts found were related to the contents of both total phosphate and total organic phosphate, and accounted, on average, for 6 per cent of the former and 17 per cent of the latter. A correlation of +0.67 (P < 0.01) was found with orthophosphate retention capacity but correlations with soil N and C contents were poor. Amounts of the esters were higher in forest soils than in grassland soils.  相似文献   
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The influence of temperature and relative humidity (r.h.) on the efficacy of glufosinate ammonium was investigated in controlled environment growth chambers using a tolerant species, barley (Hordeum vulgare L. cv. ‘Samson’), and a susceptible species, green foxtail (Setaria viridis (L.) Beauv.). The shoot ammonia concentration and visual injury of plants treated with glufosinate-ammonium doses of 100 and 800 g ha?1 were compared at day/night temperature regimes of 8/5,15/10 and 22/17°C at 60% r.h. The effect of relative humidity levels of 40% and 95% on the shoot ammonia concentration, visual injury and dry weight accumulation of glufosinate-ammonium treated plants was tested at temperature regimes of 15/10 and 22/17°C, with both species treated with 800 g ha?1. In addition, green foxtail treated with 100 g ha?1. was tested at both r.h. levels at 22/17°C. As the temperature de creased, less ammonia was produced in treated green foxtail plants. However, ammonia levels were comparable at all temperature regimes for barley. Lowest temperatures resulted in delayed injury to both species, but only small differences in injury existed among temperature regimes 288 h after spraying. The activity of glufosinate ammonium on both species was significantly de creased by low r.h. For example, when grown at 22/17°C, green foxtail survived the potentially lethal dose of 100 g ha?1 at 40% r.h. and accumulated 70% of the dry weight of control plants, but was killed at 95% r.h. Of the two environmental factors examined, r.h. had the most significant effect on the phytotoxic action of glufosinate-ammonium. L'influence de la température et de I'humidité relative sur I'efficacité du glufosinate-ammonium L'influence de la température et de 1'humidité relative (hr) sur I'efficacité du glufosinate ammonium a étéétudiée en chambre climatique en utilisant une espéce d'orge tolérante (Hor deum vulgare L. cv ‘Samson’) et une espéce sensible la svtaire verte (Setaria viridis L. Beauv). La concentration en ammoniaque des pieds et les dégats visuels des plantes traitérs avec des doses de glufosinate ammonium de 100 et 800 g/ ha?1 ont été comparés pour des régimes de températures jour/nuit de 8/5, 15/10 et 22/17°C à 60% hr. L'effet de taux d'humidité relative de 40 et 95% sur la teneur en ammoniaque des pieds, les dégats visuels et (l'accumulation de matiére séche chez des plantes traitéres au glufosinate ammonium a été testéà des régimes de températures de 15/10 et 22/17°C, pour les 2 espéces traitées à 800 g ha?1. En outre, la sétaire verte traitée à 100 g hr?1 a été testée aux 2 hr à 22/17°C. Quand la température diminue, il y a moins d'ammoniaque produit chez les sétaires vertes trailérs. Cependant les taux d'ammon iaque ont été comparables à toutes les tempéra tures chez 1'orge. Les températures les plus basses ont abouti à un retard de phytotoxicité ches les 2 espéces, mais à peu de différences entre les régimes de températures 288 h après 1'application. L'activité du glufosinate ammon ium chez les deux espèces a été significative ment réduite par des faibles hr. Par exemple cul tivée à 22/17°C, la sétaire verte a survécu à des doses potentiellement léthales de 100 g ha?1à 40% d'hr et a accumulé 70% de la matière sèche des témoins mais a été détruite à 95% d'hr. Sur les 2 facteurs environnementaux étudiés, l'hr a l'effet le plus important sur l'activité phytotoxique du glufosinate ammonium. Einfluβ von Temperatur und relativer Feuchte auf die Wirksamkeit von Glufosinat-ammonium Der Einfluß von Temperatur und relativer Feuchte (rF) auf die Wirksamkeit von Glufosinat-ammonium wurde in Klimakammern anhand einer toleranten Art, der Gersten-Sorte ‘Samson’ (Hordeum vulgare L.), und einer empfindlichen Art, der Grünen Borstenhirse (Setaria viridis (L.) Beauv.), untersucht. Die Ammonium-Konzentration im Sproß und sichtbare Schädigungen der Pflanzen, die mit Dosen von 100 und 800 g ha?1 behandelt worden waren, wurden bei Tag/Nacht-Temperaturen von 8/5, 15/10 und 22/17 °C bei 60% rF verglichen. Die Wirkung von 40 oder 95% rF auf die Ammonium-Konzentrationen im Sproß, sichtbare Pflanzenschädigungen und die Trockenmassebildung wurde bei 15/10 und 22/17°C und bei 800 g ha?1 Glufosinat-ammonium untersucht. Zusätzlich wurde die Grüne Borstenhirse mit 100 g ha?1 behandelt und bei den beiden Feuchtegraden und 22/17 °C untersucht. Mit abnehmender Temperatur bildete die Grüne Borstenhirse weniger Ammonium, dessen Gehalt bei der Gerste jedoch bei allen Temperaturen gleich war. Geringere Temperaturen verzögerten bei beiden Arten die Schädigungen, doch ließen sich 288 h nach der Behandlung nur noch geringe Unterschiede bei den verschiedenen Temperaturen beobachten. Die Wirkung von Glufosinat-ammonium war bei niedriger rF bei beiden Arten signifikant schwächer. Z. B. überlebte die Grüne Borstenhirse die potentiell letale Dosis von 100 g ha?1 bei 22/17 °C und 40% rF und bildete 70% der Trockenmasse von Kontrollpflanzen, wurde jedoch bei 95% rF abgetötet. Die rF war von den beiden untersuchten Umweltfakoren der signkfikantere für die phytotoxische Wirkung des Glufosinat-ammoniums.  相似文献   
197.
Pod rot and stem canker, caused by Phytophthora palmivora , are serious diseases of cocoa causing pod losses of up to 63% and the death of up to 10% of trees annually on Kar Kar Island. Papua New Guinea. Trials were conducted on commercial cocoa plantations to compare the effectiveness of potassium phosphonate when applied as trunk injections, trunk paints and foliar sprays, and trunk injections of Aliette CA and of Ridomil 250EC, with conventional Ridomil-based spray programmes. The results show that, in trials conducted over 5 years, injections of potassium phosphonate give the highest healthy pod yield and lowest incidence of Phytophthora pod rot and stem canker when compared with Ridomil-based spray programmes or trunk injections of Ridomil 250EC or Aliette CA. The increase in ripe healthy pod yields was due to both pod rot and stem canker control. The level of control is independent of the seasonal timing of injection. Optimum control was achieved with annual injections of 15 g a. i. per tree, and varied with tree size and disease severity. Injections of phosphonate will, under the range of conditions found in our trials. provide the most cost-effective control of Phytophthora diseases.  相似文献   
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Subtilin, a new antibiotic obtained from B. subtilis, proved active in vitro against L. plantarum, E. histolytica and its associated bacterium ;t', and T. equiperdum without causing immediate hemolysis of erythrocytes. Subtilin is tensioactive, and amounts required for antibiotic effect are within the range of surface tension activity. It was relatively nontoxic for four species of mammals, especially after intragastric administration. Gramicidin is more hemolytic and more toxic than subtilin.  相似文献   
200.
Objectives— To compare short‐ and long‐term functional and radiographic outcome of cranial cruciate ligament (CrCL) injury in dogs treated with postoperative physical rehabilitation and either tibial plateau leveling osteotomy (TPLO) or lateral fabellar suture stabilization (LFS). Study Design— Prospective observational clinical study. Animals— Medium to large breed dogs with naturally occurring CrCL injury (n=65). Methods— Dogs with CrCL injury were treated with either TPLO or LFS and with identical physical rehabilitation regimes postoperatively. Limb peak vertical force (PVF) was measured preoperatively and at 3, 5, and 7 weeks, and 6 months and 24 months postoperatively. Stifles were radiographically assessed for osteoarthrosis (OA) preoperatively and 24 months postoperatively. Results— Thirty‐five dogs had LFS and 30 dogs had TPLO. Radiographic OA scores were significantly increased at 24 months compared with preoperative scores in all dogs. Radiographic OA scores preoperatively and at 24 months were not significantly different between treatment groups. PVF was significantly increased from preoperative to 24 months among both treatment groups but not significantly different between treatment groups preoperatively or at 3, 5, 7 weeks, 6, or 24 months. Conclusion— No significant difference in outcome as determined by ground reaction forces or radiographic OA scores were found between dogs with CrCL injury treated with LFS or TPLO. Clinical Relevance— LFS and TPLO remain good options for stabilizing stifles with CrCL injury with all dogs showing significant functional improvement. This study does not support the superiority of either surgical technique.  相似文献   
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