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21.
Species of Botryosphaeriaceae are associated with canker and dieback of Eucalyptus spp. worldwide, but little is known about their effect on the host physiology. The aim of this study was to evaluate the impact of Botryosphaeriaceae isolates from nine species in three genera (Botryosphaeria, Diplodia and Neofusicoccum), previously isolated from eucalypts, on three different Eucalyptus hosts (seedlings of E. nitens, cuttings of E. globulusand of E. globulus× E. cypellocarpa). An approach combining standard pathogenicity trials with evaluation of plant morpho‐physiological parameters was used. The size of the lesions produced revealed differences in fungal aggressiveness and host susceptibility. Isolates of Neofusicoccum kwambonambienseand Diplodia corticolawere the most aggressive, while Botryosphaeria dothidea and Diplodia seriataisolates were the least aggressive. In general, hybrid E. globulus× E. cypellocarpa plants developed smaller lesions, followed by E. nitens and E. globulus. Eucalyptus nitensplants showed minimal modifications on the morpho‐physiological profile when infected, although more severe symptoms and mortality were observed. This is probably due to a more variable genetic background of the plants. However, in general, no direct association between putative fungal aggressiveness and plant physiological disorders could be found. Results suggested that under optimal growth conditions plants manage to cope with pathogen attack and maintain their physiological performance.  相似文献   
22.
Cataracts are among the most common ocular diseases, and are a leading cause of vision loss in humans and dogs. Jack Russell Terriers (JRT) and Labrador Retrievers (LR) are among the most popular canine breeds in the United Kingdom, and also among the most affected by cataracts.This study aimed to analyze the clinical features and the surgical outcome of cataracts in JRT and LR in an ophthalmologic reference Veterinary Hospital in the United Kingdom. For that purpose, medical records from JRT and LR diagnosed with cataracts between January 2015 and December 2016 were retrospectively evaluated. Data related to identification, clinical history, preoperative features, and surgical outcomes were analyzed.Forty-four dogs (81 eyes), including 26 JRT and 18 LR, were enrolled in the study. Mean ages were 10.2 ± 3.2 years in JRT and 8.5 ± 3.7 years in LR. Twenty-eight (63.6%) were females and 16 (36.4%) were males. Most dogs (84.1%) presented with bilateral cataracts. Nuclear and cortical cataracts were the most prevalent type in both breeds (JRT: n?=?30, 61.2%; LR: n?=?16, 50.0%), although subcapsular cataracts were also frequent in LR (n?=?10, 31.3%). Significant differences in cataract location within the lens were detected between the two breeds (P?=?.002).Senile in JRT (n?=?7) and genetic in LR (n?=?7) were the most common etiologies. Concomitant ocular lesions were more frequent in dogs presented with cataracts in advanced stages, and included lens (n?=?18; JRT: n?=?15; LR: n?=?3) and retinal alterations (n?=?8; JRT: n?=?2; LR: n?=?6), and glaucoma (n?=?6; JRT: n?=?5; LR: n?=?1). Thirty-three animals (75.0%, 51 eyes) were submitted to phacoemulsification with intraocular lens placement. Of these, 28 eyes (54.9%; JRT: n?=?21; LR: n?=?7) were visual, 19 eyes (37.3%; JRT: n?=?11; LR: n?=?8) presented impaired vision and four eyes (7.8%; JRT: n?=?0; LR: n?=?4) were blind at last clinical record. Postoperative complications were detected in 11 eyes (21.6%), and were more frequent in dogs presented with cataracts in advanced stages.These results and the multifactorial nature of cataracts call for further studies to identify and characterize the variables in a broader assessment, including other breeds and influencing factors.  相似文献   
23.
Three Hg sources were characterised and mass balance calculations were used to determine their relative contributions to the contamination of the Amazonian environment. About an order of magnitude more Hg is emitted to the atmosphere by goldmining activity than by the burning of forest biomass. However, anthropogenic atmospheric Hg cannot account for the high Hg burdens found in terrestrial ecosystems: deposition of Hg from goldmining sources is estimated to account for less than 3% of the Hg present in the surface horizons of soils. We propose that erosion of deforested soils following human colonization constitutes a major disturbance of the natural Hg cycle. Deforestation thus increases soil Hg mobilisation by runoff, which may explain the increase of Hg burdens in Amazonian aquatic ecosystems in newly colonized watersheds.  相似文献   
24.
This study evaluated the effects of dietary supplementation of organic acids blend (OAB) alone or in combination with essential oil, Lippia origanoides (OAE) for Nile tilapia fed supplemented diets for 30 days. Fish (1.1 ± 0.04 g) were fed control (Control), or OAB 0.5% or OAB 0.5% + essential oil 0.125% (OAE) respectively. At the end of the experiment, samples were collected for de hemato‐immunological, histological analysis of the intestine and liver, as well as microbiology of the intestine. The pH of the diets supplemented with OAB and OAE reduced 0.92 and 0.19 respectively. The growth and FCR were unaffected by the treatments, but survival was significantly higher in the OAB treatment. Fish fed the OAB diet showed reduced concentration of total heterotrophic bacteria and Pseudomonas sp. in the intestine. Increased glucose in fish fed OAB and high number of circulating monocytes in fish fed OAE diet were observed. The anterior intestine of fish fed OAE diet showed larger number of goblet cells and increased villi height. The diet supplemented with OAB, mainly, improved the intestinal health and survival of tilapia juveniles and can be used in juvenile production.  相似文献   
25.
Intensive fish farming has resulted in an increased concern for disease outbreaks. Probiotic use is one of the strategies being developed to improve fish health and productivity. Measures of probiotic colonization, growth performance, haematological characteristics and parasite load were used to evaluate the effect of diets supplemented with Enterococcus faecium on growth and health of Arapaima gigas juveniles. A completely randomized design with four treatments (diet with E. faecium at 1 × 106 CFU/g and 1 × 108 CFU/g, control diet and diet with the culture medium MRS) and three replicates was used. Ninety‐six Arapaima juveniles were distributed in 12 cages fed with the specified diet for 68 days. Colonization of the intestinal tract by lactic acid bacteria reduced the total number of heterotrophic bacteria in fish fed with probiotics compared to controls. Fish fed a supplemented diet containing 1 × 108 CFU/g presented higher values of weight gain, survival and fish growth uniformity, and lower values of feed conversion ratio. The prevalence of Trichodina sp. could have affected the survival of fish in the control group. Reduction in parasite load and an increase in haematocrit, the number of erythrocytes, thrombocytes, neutrophils and monocytes were also observed in fish fed the diet containing 1 × 108 CFU/g. Enterococcus faecium presented a probiotic effect in A. gigas juveniles and can be recommended for use at a concentration of 1 × 108 CFU/g to modify the gut microbiota, improve growth performance and haematology and reduce parasitic load.  相似文献   
26.
This work aimed to evaluate the probiotic Lactobacillus spp. in the microbiota of Astyanax bimaculatus reared in a water recirculation system. The experiment was randomized, using 800 postlarvae distributed into eight polyethylene containers, separated into two treatments, in quadruplicate: supplementation with Lactobacillus spp. (Probiotic) and no supplementation (Control). After 90 days of culture, 13 fish per container were anaesthetized. Three of these underwent microbiological evaluation, and haematological analyses were carried out on five. Immunological assessment was performed on another five fish. Zootechnical parameters were evaluated for all animals. In the microbiological evaluation, the probiotic group presented higher counts of lactic acid bacteria, but lower counts of Vibrio spp., Pseudomonas spp., and Staphylococcus spp., when compared with control. After haematological analysis, the supplemented group presented low haematimetric indices of Mean Corpuscular Haemoglobin Concentration and Mean Corpuscular Haemoglobin (MCHC and MCH, respectively) and higher amounts of total leucocytes, thrombocytes and circulating monocytes when compared with control. The immunological profile did not differ between treatments. In the zootechnical performance, probiotic group presented higher productivity, survival and apparent food efficiency when compared with control. Therefore, when Lactobacillus spp. was supplemented in the diet of A. bimaculatus, immunocompetence and the zootechnical performance of animals increased.  相似文献   
27.
This study relies on the Flying Beauties Citizen Science project conducted in the Philippines to assess personal motivations and learning outcomes of volunteers who were involved in documenting butterflies and dragonflies in rice ecosystems. While evaluation of motivations of volunteers in Citizen Science is not new, at least in affluent western countries, little is done in investigating volunteers’ motivations and learning outcomes of Citizen Science projects in low-income countries. Using surveys, we collected data from volunteers that were analysed qualitatively and quantitatively. We adopted a two stages evaluation format—before and after volunteers finished the project exercise. We compared pre-motivations to motivations attained and changes in level of knowledge before and after the project ended. We use Spearman’s Rho, Kendall’s Tau—nonparametric tests to draw correlations between variables. The results showed that key determinants that drove people to volunteer in the project were (a) learning about species and (b) being part of scientific research and the principal learning outcome was improved awareness about ecosystem functions of the species.  相似文献   
28.
墨西哥锡那罗亚是拉丁美洲最重要的粮食生产区。2009年以来,霜冻和大风不断袭击该区,造成作物减产25%,损毁作物17万hm2,每年损失粮食折合5亿美元。在锡那罗亚州,引种麻竹作为一种主要的经济作物,可以弥补因气候变化导致的粮食损失,并可为墨西哥西北部地区增加17万hm2的竹林。麻竹鲜笋亦可销往墨西哥其他地区、美国南部和中美洲各国。文章旨在阐述当前气候变化背景下竹子资源为人类带来巨大效益的潜力,并可进行商业性生产。在中国的大力帮助下,在墨西哥设计建立了一个竹子商业性生产的试验项目,以此说明竹子在提高人们生活质量方面的潜力。总之,竹子及其相关产业的社会经济价值会极大地影响墨西哥锡那罗亚人们的生活方式。  相似文献   
29.
Epidemiological studies have shown a relation between antioxidants and the prevention of several chronic diseases. Microalgae are a potential novel source of bioactive molecules, including a wide range of different carotenoids that can be used as nutraceuticals, food supplements and novel food products. The objective of this review is (i) to update the research that has been carried out on the most known carotenoids produced by marine microalgae, including reporting on their high potentialities to produce other less known important compounds; (ii) to compile the work that has been done in order to establish some relationship between carotenoids and oxidative protection and treatment; (iii) to summarize the association of oxidative stress and the various reactive species including free radicals with several human diseases; and (iv) to provide evidence of the potential of carotenoids from marine microalgae to be used as therapeutics to treat or prevent these oxidative stress-related diseases.  相似文献   
30.
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