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1.
Removal of the spinal cord is considered time consuming and difficult. A delay in the necropsy procedure, especially in the central nervous system, can result in significant tissue autolysis and subsequent diagnostic difficulties. In the field, where many necropsies are performed, suitable electric saws are mostly unavailable. A technically simple and rapid method for spinal cord removal, requiring only a straightforward tool, has been devised. No necropsy-induced structural damage has been noted on histopathologic examination.  相似文献   
2.
The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper.  相似文献   
3.
The state of demersal fishery in the Southern Adriatic Sea (GFCM-GSA 18, Central Mediterranean), years 1996–2003, from a biological, social and economic point of view was analysed using 47 indicators: 22 biological indicators obtained from fishery-independent data through yearly experimental bottom trawl surveys (“Medits” Programme), and 25 socio-economic indicators estimated from fishery-dependent data, available from the monitoring system of the Italian Institute for Economic Research on Fisheries and Aquaculture (IREPA). Biological indicators were applied for “single-species” (Eledone cirrhosa, E. moschata, Illex coindetti, Merluccius merluccius, Mullus barbatus, Nephrops norvegicus, Parapenaeus longirostris, Raja clavata, Zeus faber) and for “multi-species” analysis. Economic indicators describing economic performance, productivity, costs and prices, and the overall economic sustainability of fishery were estimated. Social indicators and a general indicator summarising social sustainability were also considered. Indicators’ values were displayed using the Traffic Light system. Both fishery-independent and fishery-dependent indicators highlighted a progressive decline of the trawl fishery system in the GSA 18. This decline was mainly related to the ongoing depletion of the traditional fishery target species (mostly long-living, late-maturing species) partially replaced by the increase of traditional accessory species (generally short-living species), as well as to the reduction of productivity and increasing costs. The whole procedure was proposed as a contribution to the identification and applicability of bio-economic indicators for fishery management purposes.  相似文献   
4.
Abstract

Leaf-cutting ants (LCA) are considered one of the main herbivores and one of the most destructive pest insects of the Neotropics. Northeastern Argentina harbors the greatest species richness of these ants and in turn comprises the highest surface with forest plantations. Our aim was to establish which species of leaf-cutting ants are most commonly associated with forest plantations by analyzing their geographic distribution using published and unpublished species occurrence data. Also, estimate their potential areas of distribution along a latitudinal gradient that entirely encompasses northeastern Argentina using Ecological Niche Modeling. Only seven of the 20 species recorded were strongly associated with productive systems along the gradient, but only 2–3 species in each region could be considered high-risk species for forest plantations. High-risk species composition shows a turnover between regions. Our models show the potential distribution areas where LCA could become more abundant and dominant, and possibly causing a detrimental effect on the forest plantations in the studied region. We find that ecological niche models are useful tools to assess the environmental suitability of important LCA.  相似文献   
5.
A 70‐day growth trail was conducted to investigate the effects of inclusion of high levels of meat and bone meal (MBM) and protein concentrate (PC) on growth, digestibility and economic performances of climbing perch, Anabas testudineus. Four isonitrogenous diets were formulated by lowering the level of dietary fishmeal protein at 0 (D1, control), 70 (D2), 85 (D3) and 100% (D4) with a mixture of MBM and PC protein (1:1). Triplicate groups of 300 fish (mean weight of 0.80 g) stocked in each 40 m2 pond and fed the respective test diets. A digestibility trial was conducted after the growth trial in indoor glass aquarium. The result showed that growth parameters were significantly decreased (P < 0.05) with fishmeal replacement levels. However, significant differences were not found in feed conversion ratio and survival of fish. No difference was also found in protein efficiency ratio among D1, D2 and D3. Similar to growth parameters, total fish production was highest in D1, intermediate in D2 and D3; and lowest in D4. Apparent digestibility coefficients of dry matter, protein and lipid were highest (P < 0.05) in D1 and lowest in D4. The economic analysis revealed that the benefit cost ratio was ranked by D3 (1.81), D2 (1.71), D1 (1.66) and D4 (1.46) respectively. Upon considering the overall performances and unavailability of finite protein sources, it can be concluded that 70–85% fishmeal could be replaced with a mixture of MBM and PC (1:1) in practical diets for climbing perch.  相似文献   
6.
Neurotoxicity complicates the use of several commonly administered chemotherapeutic agents (platinum based alkylating agents, taxanes and vinca alkaloids), with chemotherapy-induced peripheral neuropathy being the most common manifestation. Structural damage to the peripheral nervous system results in positive symptoms, e.g., allodynia, hyperalgesia and pain with unpleasant features as burning and shooting. Patients are unable to complete full or optimal treatment schedules. The pathophysiologic basis of nerve injury in chemotherapy-induced peripheral neuropathy is incompletely understood and appears to be unique for each class of the chemotherapeutic agents. Erythropoeitin (EPO), a well-established hematopoietic factor, is a very effective and widely used treatment for anemia in cancer patients undergoing chemotherapy. It also possesses generalized neuroprotective and neurotrophic properties. Co-treatment of chemotherapy and erythropoietin has been proposed for preventing or reversing the disabling peripheral neuropathy induced by the different chemotherapeutic agents. This study first describes the pathophysiological background of the clinically relevant chemotherapeutic agents-inducing peripheral neuropathy. Secondly, the possible mechanisms that might underlie the neuroprotective effect of erythropoietin in chemotherapy-induced neuropathy. Further clinical trials of EPO in cancer patients receiving chemotherapy and suffering from neurological symptoms seem to be warranted in the future. This might improve the quality of life in cancer patients.  相似文献   
7.
由联合国粮农组织认定的全球重要农业文化遗产(GIAHS)是一类典型的社会生态生产景观(SEPLS),在传统知识传承保护、粮食与食物安全保障、农业生物多样性保护、气候变化应对等诸多方面具有重要意义。为了更好、更有效地开展GIAHS保护及管理工作,本文在分析GIAHS评估重要性和恢复力概念的基础上,以联合国大学(UNU)等团队开发的社会生态生产景观恢复力评估框架(SEPLS模型)为基础,构建了GIAHS恢复力评估框架(GIAHS-RAF),明确了其评估及计算过程。并以中国第1个GIAHS项目——浙江青田稻鱼共生系统(Qingtian Rice-Fish Culture System in Zhejiang Province, RFC)为例,通过对核心保护区——龙现村在2004年(GIAHS项目授牌前)和2016年(GIAHS授牌11年)的恢复力状况进行评估,探讨模型在GIAHS保护成效评估中的适用性。研究结果显示:1)2016年龙现村恢复力整体状况相对较弱,各项资本评估得分为:物质资本(0.75)经济资本(0.63)人类资本(0.61)社会资本(0.57)自然资本(0.38);2)虽然农户收入来源多样且社会经济基础设施能较好地满足社区需求,但是遗产地内部农业物种较少,农户对于系统提供的粮食多样性尚不是非常满意; 3)相较于2004年,经过11年的保护工作,研究区恢复力有所提高,说明GIAHS项目的实施对该遗产的恢复力有积极影响,尤其是物质资本和经济资本两方面。评估结果与该区域相关研究结果及实地调查情况一致,说明所构建的GIAHS恢复力评估框架可以很好地应用于对GIAHS项目及其他相关农业文化遗产的保护成效评估工作。  相似文献   
8.
Prolonged exposure to captive conditions has led to the development of a rainbow trout ‘farmed’ phenotype, which is different from that of wild trout. Selection for desirable productive traits in hatcheries has resulted in the development of some morphological traits that are maladaptive in nature. The recent development of organic aquaculture, guided by the well‐being of the fish, could potentially produce a new farmed phenotype that would be more adaptive in nature. In this study, rainbow trout reared in intensive and organic farms were compared by means of shape analysis, to detect patterns of shape variation associated with rearing environment. The results of this study highlight a significant effect of the rearing method on rainbow trout shape: organically reared trout showed a higher body profile, in particular in the head and trunk regions, shorter median fins and a deeper caudal peduncle. A combined effect of density and habitat complexity could have contributed to the observed shape differences: in organic rearing systems, lower densities and steady water could increase territoriality and aggressive interactions, promoting body designs more functional in rapid attacks and escapes.  相似文献   
9.
OBJECTIVE: To determine the diagnostic value of aerobic microbial culture and cytologic evaluation of corneal specimens in the diagnosis of infectious ulcerative keratitis (IUK). DESIGN: Prospective study. ANIMALS: 48 animals (26 dogs, 13 horses, 7 cats, 1 bird, and 1 llama) with corneal ulcers. PROCEDURE: Scrapings from corneal ulcers were examined cytologically. Corneal swab specimens were submitted for microbial culture. Animals were grouped according to whether they had been receiving antimicrobials at the time of admission. RESULTS: Of the 38 animals receiving antimicrobials, 19 had positive results for IUK on cytologic evaluation, 20 on microbial culture, and 26 on cytologic evaluation, microbial culture, or both. Of the 10 animals not receiving antimicrobials at the time of admission, 7 had positive results for IUK on cytologic evaluation, and 9 had positive results on microbial culture. In this group of 10 animals, additional animals with IUK were not identified on the basis of cytologic evaluation alone. When all 48 animals were considered irrespective of antimicrobial treatment, 26 and 29 had positive results for IUK on cytologic evaluation and microbial culture, respectively, whereas IUK was confirmed in 35 animals on the basis of cytologic evaluation, microbial culture results, or both. CONCLUSIONS AND CLINICAL RELEVANCE: Microbial culture and cytologic evaluation of corneal specimens maximizes identification of IUK, especially in animals receiving antimicrobial treatment. Because of serious consequences of untreated IUK, we recommend that both diagnostic tests be used to tailor treatment and reduce risk of vision impairment in animals.  相似文献   
10.
The antifeedant effect of five organotin compounds (fentin acetate, fentin hydroxide, fentin chloride, cyhexatin and fenbutatin oxide) and of three other compounds known to possess antifeeding activity (guazatine triacetate, 4′-chloroacetophenone isobutyrylhydrazone and thiram) was investigated by feeding treated alfalfa to larvae of Boarmia selenaria. The three fentins and cyhexatin were highly active at 0.1 g litre?1, the order of activity at this concentration being fentin chloride > fentin hydroxide > fentin acetate ? cyhexatin, whereas the other compounds were practically inactive at either this or a somewhat higher concentration (0.5 g litre?1). Guazatine triacetate had a concentration-independent antifeedant effect at much higher concentrations (5–20 g litre?1).  相似文献   
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