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71.
Cristian Javier Antonelli Pablo Ignacio Calzadilla Juan Manuel Vilas María Paula Campestre Francisco Jos Escaray Oscar Adolfo Ruiz 《Journal of Agronomy and Crop Science》2019,205(1):65-76
Cattle production based on natural pastures is often subject to flooding periods, which affect plant performance and as a result, forage production. Although most forage legumes are not tolerant to flooding, Lotus spp. are outstanding alternatives, since species, such as L. tenuis (Lt) and L. corniculatus (LcT), have high forage quality and are adaptable to different environments. We recently obtained a L. tenuis × L. corniculatus hybrid (LtxLc) with potential new cultivar traits, although its tolerance to flooding stress has not yet been evaluated. In the present study, the performance of LtxLc, its parental diploid accessions, the model legume L. japonicus and tetraploid LcT were evaluated under 55 days of partial submergence stress and a 35‐day recovery period. Physiological, morphological and anatomical traits were analysed, showing that tolerance to partial submergence was positively associated with aerenchyma and adventitious root formation and relative growth rates. Overall, Lt and LtxLc showed the best responses under stress and during the recovery period. Nevertheless, the higher forage value of LtxLc makes it recommendable for use in environments affected by flooding. Our results could be used as breeding criteria for the generation of new cultivars tolerant to partial submergence stress. 相似文献
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Mariana N. Ştefănuţ Adina Căta Raluca Pop Cristian Tănasie Daniel Boc Ioana Ienaşcu Valentin Ordodi 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):378-384
Small fruits like bilberry, blackberry and mulberry are rich sources of anthocyanins and other phenols, compounds with a certified antioxidant activity and spectacular effects in some chronic diseases. Romanian bilberry, blackberry and mulberry extracts were tested as anti-hyperglycemic agents on diabetic rats. Anthocyanins extraction was carried out with 80 % acidified ethanol in ultrasonically conditions at 23?±?2 °C and 40 kHz. Monomeric anthocyanins content was determined by pH differential method and varied between 1200 and 2800 mg/L. The analyses of anthocyanins were achieved using high performance liquid chromatography and mass spectrometry. Phenolics content was determined by Folin-Ciocalteu procedure and values varied between 2320 and 4250 mg/L gallic acid. Antioxidant activities of extracts were estimated by DPPH scavenging method and the values varied between 8 and 16 miliequivalents Trolox. In order to evaluate the toxicology of the extracts, the heavy metals concentration and pesticides content were analyzed. The extracts were administrated to diabetic rats in drinking water for five weeks. The administration of bilberry extract offered no satisfactory results. Treatment with blackberry extract determined a significant decrease of glucose level from 360 to about 270 mg/dL (p?<?0.05). The mulberry extract administration determined a significant decrease of glucose level from 252 mg/dL at the start day to 155 mg/dL at the final of experiment (p?<?0.05). 相似文献
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Marianne Werner Christian Hepp Cristian Soto Paz Gallardo Hedie Bustamante Carmen Gallo 《Livestock Science》2013,152(1):42-46
In Chile, prolonged transport of cattle is an important issue due to geographical conditions. This study describes the variation of body weight and some blood constituents related to stress response during one long distance transport (63 h) of recently weaned calves for fattening in the Chilean Patagonia. Results concerning blood variables related to stress showed that the whole process of rounding up, weaning and transport was stressful for the calves and that animal welfare was impaired. Cortisol values were significantly lower after unloading (1.0±0.4 μg/dl), as compared to before loading (1.5±0.4 μg/dl). The significant body weight loss from before loading (240±26.9 kg) to after unloading (210±24.2 kg), and the long recovery time, adds economic losses to the producers at destiny. As transport period cannot be shortened due to the typical Chilean geography in the Patagonian region and the scarcity of proper routes, it is recommended that conditions of transported calves should be improved by using specialized livestock vehicles that can provide more comfort, as well as access to water and food during the journey. 相似文献
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Rubilar M Jara C Poo Y Acevedo F Gutierrez C Sineiro J Shene C 《Journal of agricultural and food chemistry》2011,59(5):1630-1637
The objective of this work was to evaluate the antioxidant and antihemolytic activities of crude, aqueous, and organic-aqueous extracts of maqui ( Aristotelia chilensis ) and murta ( Ugni molinae Turcz.), together with their inhibiting effect on enzymes involved in the metabolism of carbohydrates. Radical scavenging activity, inhibition of linoleic acid oxidation in a micellar system, antihemolytic activity, and inhibition of α-amylases and α-glucosidases were analyzed. Crude extracts of maqui leaves and fruits were found to be important sources of polyphenolic compounds, showing 69.0 ± 0.9 and 45.7 ± 1.1 mg GAE/g dm, respectively. Polyphenols from maqui leaves were active as antioxidants and antihemolytic compounds (p < 0.05), showing a noncompetitive inhibiting effect on α-glucosidase. Flavan-3-ol polymers and glycosylated flavonols, such as quercetin glucoside and kaempferol glucoside, were tentatively identified in extracts. This preliminary observation provides the basis for further examination of the suitability of polyphenol-enriched extracts from maqui and murta as nutritional or medicinal supplements with potential human health benefits. 相似文献
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Campos Carla Cristian do Prado Francisco Luiz dos Reis João Paulo Justo Carneiro Luisa Cunha Silva Paula Regina Basso de Moraes Giovanna Faria dos Santos Ricarda Maria 《Tropical animal health and production》2020,52(6):3061-3068
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of clinical mastitis (CM) occurring before or after the first AI postpartum, and puerperal diseases... 相似文献
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John Reid Aaron Bruner Jeffrey Chow Alfonso Malky José Carlos Rubio Cristian Vallejos 《Journal of Sustainable Forestry》2015,34(6-7):605-622
Large development projects commonly cause damage to ecosystems, even after measures have been taken to avoid and reduce impacts on site. Governments are increasingly seeking to offset losses through ecological compensation programs to maintain overall levels of biodiversity and ecosystem services. The key to successful programs are criteria that reduce uncertainty and transaction costs while enhancing ecological equivalency. In South America, the government of Brazil, and Colombia have implemented compensation programs, and Peru has recently published broad guidelines and is developing detailed rules. Brazil emphasizes regulatory simplicity, which mitigates cost uncertainty, over ecological equivalence. Colombia has sophisticated methods for establishing ecological equivalence, but has yet to develop institutions necessary to reduce transaction costs. These experiences suggest a trade-off between rules that rigorously compensate losses with ecologically equivalent areas, and simpler approaches that have low transaction costs but may fail to ensure specific biodiversity goals. The success of Peru’s system will depend on being practical enough to implement at scale and rigorous enough to deliver environmental benefits. We describe a series of mutually compatible recommendations to balance both needs. Ecological compensation is still a nascent effort in the neotropics and policy adjustments will be necessary as better information on success and failure becomes available. 相似文献
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Cristian Echeverria David Coomes Javier Salas Jos María Rey-Benayas Antonio Lara Adrian Newton 《Biological conservation》2006,130(4):481-494
The temperate forests of Chile are classified a biological “hotspot” as a result of their high species diversity and high endemism. However, they are being rapidly destroyed, with significant negative impacts on biodiversity. Three land-cover maps were derived from satellite imagery acquired over 25 years (1975, 1990 and 2000), and were used to assess the patterns of deforestation and forest fragmentation in the coastal range of south-central Chile. Between 1975 and 2000, there was a reduction in natural forest area of 67% in the study area, which is equivalent to an annual forest loss rate of 4.5% per year using a compound-interest-rate formula. Forest fragmentation was associated with a decrease in forest patch size, which was associated with a rapid increase in the density of small patches (<100 ha), and a decrease in area of interior forest and in connectivity among patches. Since the 1970s, native forest loss was largely caused by an expansion of commercial plantations, which was associated with substantial changes in the spatial configuration of the native forests. By 2000, most native forest fragments were surrounded by highly connected exotic-species plantations. The assessment of forest loss and fragmentation provides a basis for future research on the impacts of forest fragmentation on the different component of biodiversity. Conservation strategies and land use planning of the study area should consider the spatial configuration pattern of native forest fragments and how this pattern changes over time and space at landscape level. 相似文献
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Roberto José-López Cristian de la Fuente Martí Pumarola Sonia A?or 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(10):948-954
Clinical, imaging, and histological features of 8 canine spinal meningiomas, including a cervical cystic meningioma with imaging and intraoperative features of an arachnoid cyst, are described. All meningiomas were histologically classified and graded following the international World Health Organization human classification for tumors. Six meningiomas were located in the cervical spinal cord. Myelography showed intradural/ extramedullary lesions in 3/4 cases. Magnetic resonance imaging revealed hyperintense intradural/extramedullary masses on pre-contrast T1-weighted and T2-weighted images with homogeneous contrast enhancement in 7/8 cases. One dog had a cerebrospinal fluid-filled subarachnoid cavity dorsal to the cervical spinal cord. A spinal arachnoid cyst was diagnosed on imaging, but the histopathological study of the resected tissue revealed a grade I meningothelial cystic meningioma. There were no differences in outcome associated with tumor grade and surgical treatment (6/8). Cystic meningioma should be considered in the differential diagnosis of intraspinal cystic lesions, and biopsy is necessary for definitive diagnosis. 相似文献