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161.
Olive oil mill wastewaters (OMWs) show significant polluting properties due to their content of organic substances, and because of their high toxicity toward several biological systems. Wastewaters' toxicity has been attributed to their phenolic constituents. A chemical study of wastewaters from a Ligurian oil mill characterized phenolic products such as 1,2-dihydroxybenzene (catechol), derivatives of benzoic acid, phenylacetic acid, phenylethanol, and cinnamic acid. The OMWs were fractioned by ultrafiltration and reverse osmosis techniques and tested for toxicity on aquatic organisms from different trophic levels: the alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum); the rotifer Brachionus calyciflorus; and two crustaceans, the cladoceran Daphnia magna and the anostracan Thamnocephalus platyurus. The fraction most toxic to the test organisms was that from reverse osmosis containing compounds of low molecular weight (<350 Da), and this was especially due to the presence of catechol and hydroxytyrosol, the most abundant components of the fraction.  相似文献   
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Land degradation reducing vegetation cover may affect the soil surface‐active fauna because both aboveground and belowground invertebrates depend on complex plant communities. In this study, we evaluated the effect of land degradation and restoration on soil fauna in northeast Brazil. Sites differed in degradation status: native vegetation, moderately degraded land, highly degraded land, and land under restoration for 4 years. Araneae and Coleoptera densities were significantly higher in natural vegetation and restored land (8 ± 4 ind./trap and 41 ± 21 ind./trap, respectively) than in degraded lands (−73% and −81%, respectively). The density of Formicidae was significantly higher in natural vegetation (206 ± 181 ind./trap) than in highly degraded land (32 ± 24 ind./trap), while restored land (51 ± 10 ind./trap) and moderately degraded land (37 ± 14 ind./trap) did not differ significantly from the other degradation levels. The density of Orthoptera did not follow the aforementioned patterns, while invertebrate groups mostly had highest densities in natural land and restored land. Linear regressions showed a strong negative relation between faunal density and soil bulk density, and a positive relation with soil organic matter due to an increase in plant cover. Our results indicate that land degradation simplifies soil surface‐active invertebrate communities with pronounced decreases in the density of Araneae, Coleoptera, and Formicidae, but that land restoration practices may recover the density of soil fauna even after only 4 years. Araneae, Coleoptera, and Formicidae respond sensitively to land degradation and restoration practice and are suggested as indicator groups for restoration success. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
164.
The present experiments on goats were conducted with the aim of verifying (a) whether the identity of the goat kids can affect the characteristics of milk let-down during suckling (Study 1) and (b) whether the presence of the goat kids may improve the milk let-down during hand milking (Study 2). In Study 1, 16 lactating goats with twins and 12 with single kids were used. Dams with single goat kids ejected more milk when suckling their kids at Days 5 and 20 of lactation, than when suckling aliens. Dams with twins ejected more milk when suckling their own kids than aliens only at Day 5 of lactation. Taking into account all the dams, they ejected more milk with more fat, protein, and lactose during suckling their own litter than when suckling aliens. In Study 2, when dams (n = 13) were hand milked in the presence of their own litter or in its absence, they ejected more milk with more fat, protein, and lactose than when milked in the presence of alien kids. We conclude that milk let-down in goats can be influenced by the type of stimuli applied or to which they are exposed to during suckling and milking.  相似文献   
165.
ObjectiveTo evaluate the evidence of analgesic efficacy of tramadol for the management of postoperative pain and the presence of associated adverse events in dogs.Databases usedA comprehensive search using PubMed/MEDLINE, LILACS, Google Scholar and CAB databases with no restrictions on language and following a prespecified protocol was performed from June 2019 to July 2020. Included were randomized controlled trials (RCTs) performed in dogs that had undergone general anesthesia for any type of surgery. Two authors independently classified the studies, extracted data and assessed their risk of bias using Cochrane’s tool. RevMan and GRADE methods were used to rate the certainty of evidence (CoE).ConclusionsOverall 26 RCTs involving 848 dogs were included. Tramadol administration probably results in a lower need for rescue analgesia versus no treatment or placebo [moderate CoE; relative risk (RR): 0.47; 95% confidence interval (CI): 0.26–0.85; I2 = 0%], and may result in a lower need for rescue analgesia versus buprenorphine (low CoE; RR: 0.50; 95% CI: 0.20–1.24), codeine (low CoE; RR: 0.75; 95% CI: 0.16–3.41) and nalbuphine (low CoE; RR: 0.05; 95% CI: 0.00–0.72). However, tramadol administration may result in an increased requirement for rescue analgesia versus methadone (low CoE; RR: 3.45; 95% CI: 0.66–18.08; I2 = 43%) and COX inhibitors (low CoE; RR: 2.27; 95% CI: 0.68–7.60; I2 = 45%). Compared with multimodal therapy, tramadol administration may make minimal to no difference in the requirement for rescue analgesia (low CoE; RR: 1.12; 95% CI: 0.48–2.60; I2 = 0%). Adverse events were inconsistently reported and the CoE was very low. The overall CoE of the analgesic efficacy of tramadol for postoperative pain management in dogs was low or very low, and the main reasons for downgrading the evidence were risk of bias and imprecision.  相似文献   
166.
The 26 December 2004 Indian Ocean tsunami had major effects on coastal communities and ecosystems. An assessment of coastlines after the tsunami indicates that coastal vegetation such as mangroves and beach forests helped to provide protection and reduce effects on adjacent communities. In recent years, mangroves and other coastal vegetation have been cleared or degraded along many coastlines, increasing their vulnerability to storm and tsunami damage. Establishing or strengthening greenbelts of mangroves and other coastal forests may play a key role in reducing the effect of future extreme events.  相似文献   
167.
European Journal of Forest Research - Subject to overexploitation in the past centuries, the Atlantic Forest is subject to very rigorous protection rules. However, the law is a controversial issue...  相似文献   
168.
In the past two decades, several cytogenetic screening programmes identified different chromosome rearrangements in pig, most of which represented by reciprocal translocation (rcp). This chromosome abnormality does not involve the variation in the number of chromosomes, but only the rearrangement of genetic material, resulting in phenotypically normal carriers with fertility problems. During an occasional cytogenetic screening, a new reciprocal translocation was detected in the black Lucano pig native breed. We analysed 15 animals reared by a family-run piggery in Basilicata region (Southern Italy). After karyotyping, four pigs (two boars and two sows) revealed two unpaired chromosomes. Analysis of the RBA karyotype and the dual-colour FISH technique confirmed that these pigs showed the same reciprocal translocation involving the chromosomes SSC3 and SSC6. The precise location of breakpoints was identified by RBH-FISH t(3;6)(p14;q26), whereas the analysis of the pedigree showed a case of Mendelian inheritance within a family, after the de novo occurrence of the new rcp. Considering the consequences of the rcp on the fertility, this study points out the importance of the cytogenetic screening in the native breeds for the safeguard of the genetic biodiversity and the sustainability of the rural areas.  相似文献   
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用于控制家禽沙门氏菌的"多重阻断"(multi-hurdle)型饲料添加剂新概念具有广阔的应用前景.此类添加剂是由有机酸、中链脂肪酸(MCFA)、丁酸盐和甘露二糖组成的混合物,可显著降低盲肠中的肠炎沙门氏菌(S.Enteritidis).该方法的原理是将对沙门氏菌在肉鸡肠道增殖、黏附或侵袭具有控制或阻断作用的添加剂复合在一起同时使用.  相似文献   
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