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This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all – a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.  相似文献   
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ABSTRACT

Sunflower is a species that is sensitive to local climate conditions. However, studies that use artificial neural networks (ANNs) to evaluate this influence and create tools such as agricultural zoning of climate risk (ZARC) have not been conducted for this species. Due to the importance of sunflower as a human food source and for biodiesel production, and also the necessity of conducting research to evaluate the suitability of this oleaginous species under different climatic conditions. Thus, we seek to construct a ZARC for sunflower in Brazil simulating sowing on different dates and using meteorological elements spatialized by ANNs. Climate data were used: air temperature (T), rainfall (P), relative air humidity (UR), solar radiation (MJ_m?2_d?1) and wind velocity (U2). Climatic regions considered suitable for the cultivation of sunflower had average annual values for T between 20 and 28°C, P between 500 and 1.500 mm per cycle, and soil water deficit (DEF) below 140 mm per cycle. A neural network is an efficient tool that can be used in spatialization of climate variables quickly and accurately. Sunflower sowing in the spring and summer are the ones that provide the largest suitable areas in southeastern Brazil, with 58.13 and 64.36% of suitable areas, respectively.  相似文献   
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Research has shown the occurrence of the hormesis effect in some upland rice cultures resulting from low-dose application of glyphosate. Glyphosate herbicide is widely used in Brazilian agriculture for controlling the large quantity of weeds. The aim of this work was to verify the effects of low-dose application of glyphosate herbicide on agronomic characteristics in upland rice. The experimental design used was randomized blocks comprising five low-dose applications of glyphosate herbicide (10, 20, 40, 70, and 100?g acid equivalent [a.e.] ha?1) and the control, in two stages of development of the rice culture (tillering [V4] and floral differentiation [R1]) with four repetitions. The agronomic traits of upland rice were evaluated. Data were subjected to variance analysis, polynomial regression analysis for the quantitative factor, and Tukey’s test for the qualitative factor at p?<?0.05. The grain yield and the number of spikelets per panicle increased with the application of 10?g a.e. ha?1 of glyphosate at the floral differentiation stage. Until the low dose of 75?g a.e. ha?1, there was an increase in the number of panicles. Low doses between 70 and 100?g a.e. ha?1 applied in R1 provided less spikelets per panicle, lower 100-grain weight, and lower grain yield. The leaf flavonoid content increased due to the increase in the low doses of glyphosate herbicide.

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Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy.  相似文献   
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The effects of crude extracts, fractions and isolated compounds from Vitex polygama Cham. and Siphoneugena densiflora Berg were evaluated on the development of Spodoptera frugiperda JE Smith, a destructive insect pest of corn and several other crops. The extracts and fractions were incorporated into an artificial diet at 1 mg g(-1) and offered to the insect during its larval stage. Length and viability of larval and pupal stages as well as pupal weight were assessed. Isolated compounds were tested through superficial contamination of the diet at 0.1 mg g(-1). Weight and viability of ten-day-old larvae were determined. Methanolic and hydroalcoholic S. densiflora extracts caused 100% larval mortality, while leaf and fruit hydroalcoholic extracts from V. polygama were the most active. Among the isolated compounds, flavonoids presented the best insecticidal results, and tannins the best larval growth inhibition.  相似文献   
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Feces from 34 species of ruminants housed at the Lisbon Zoo was examined for Cryptosporidium spp. oocysts. Three hundred and eighty-eight samples were analyzed. Three hundred and eighty species-specific group fecal samples were collected monthly, from September 1998 until August 1999, along with eight individual specimens from eight neonates. All samples were examined by four different techniques: microscopic observation of direct and concentrated fecal smears, staining with modified Ziehl-Nielsen, immunofluorescent assay, and immunoenzymatic assay. The prevalence of infection was 3.6%. Five neonates with diarrhea were infected. Cryptosporidial oocysts were shed more frequently during winter months. Some facilities may have permitted oocysts to remain viable, possibly contributing to cryptosporidial transmission between animals.  相似文献   
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