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Santiago, Chile

Diaz-Villanueva J.,Fundacion Chile | Robotham H.,Diego Portales University
Latin American Journal of Aquatic Research | Year: 2015

The traditional slaughter procedure of rainbow trout (Onconrhynchus mykiss) by automatic stunning followed by bleeding by cutting gills was compared with an alternative slaughter procedures which involves rapid decreasing temperature (-3.5°C) by immersion in flow-ice without gill bleeding. Muscle pH was measured as an indicator of stress achieved during confinement and sacrifice phases. The capacity of blood retention in the gut and head is proposed as potential sources to assess biosecurity. The average weight of gut and head per fish with the alternative method was 24.4 g higher than the traditional method, equivalent to 1.04% of the body weight of an average specimen. The alternative method accumulated 5.3% more weight in gut per fish than the traditional method and 4.9% more in the head weight than the traditional method. The amount of blood retained in the gut and head with the alternative method represented 44.6% of total shed by the traditional method. For a forecast of 900,000 ton of salmonids in 2014, the blood retained in gut and head was estimated in at least 9,630 ton. No significant differences in muscle pH between the two methods were observed. The pH of the fish in the confinement point was equal to 7.06 decreasing approximately to 6.5 in the sacrifice phase independent of the method employed. The alternative method does not produce instant death of the fish; however, it has more capacity than the traditional method to retained blood in gut and head to be used in increasing biosecurity and if combined with more efficient methods to achieve rapid unconsciousness, e.g. electrical stunning, we would have a combined sacrifice method useful to improve current methods. The proposal for more efficient and effective slaughter methods of fish is an open issue that requires further investigations. Keywords: Onconrhynchus mykiss, rainbow trout, pH, stress, slaughter, gill cut, biosecurity. © 2015, Escuela de Ciencias del Mar. All rights reserved. Source

Gomez J.,Ministry of the Environment of Chile | De La Maza C.,Fundacion Chile | Melo O.,University of Santiago de Chile
Water Policy | Year: 2014

An important challenge for policymakers worldwide is how to respond to increasing water demand while still assuring healthy ecosystems via 'environmental flows'. In the case of Chile, increasing water demand and frequent water supply shortages are putting pressure on ecosystem water requirements. On the other hand, new environmental regulations are being implemented to improve the quality of several bodies of water. Consequently, there is a call for water policies that can properly tackle these complex issues. The purpose of this paper is to estimate the costs of a programme to buy back water rights to restore an environmental flow in the Maipo River, as well as assess the performance of 'pollution-dilution' as a measure to comply with water quality standards in the river's basin. Results suggest that a programme that aims to buy back 440 l/s requires expending US$1.9 million, as a one-time expense. We also find that buying and leaving water flows in the river for the distinct purpose of pollution-dilution could be an efficient policy, albeit limited in impact, to reduce nutrient contamination costing about one-fifth of alternative measures to attain the same level of pollution reduction. © IWA Publishing 2014. Source

Agency: Cordis | Branch: FP7 | Program: CP-SICA | Phase: ENERGY.2008.3.2.1 | Award Amount: 4.82M | Year: 2009

The increasing reliance on imported diesel fuels, in addition to annual increases in the quantities of organic wastes are threats to the EU and Latin America. This project (DIBANET) will combat these threats and help to eliminate diesel imports by developing novel technologies that will allow the sustainable production of diesel miscible biofuels from wastes. It will build on the key, complementary, strengths of researchers and industries of both regions to advance this field. This enhancement of co-operation will ensure that the whole process, from feedstock to process residues, is engineered for maximum efficiency. The links between regions will be further enhanced by the establishment of inter-regional student scholarships; 2 large brokerage events to engage all stakeholders; and a summer school for knowledge transfer. DIBANET will increase the yield from biomass, beyond the current art, of levulinic acid, a valuable platform chemical that can be combined with ethanol to make a diesel fuel. Processes will be advanced to utilise the solid residue that remains after the acid-treatment. From this residue treatment process a bio-oil and biochar will result. The bio-oil will be upgraded to produce a diesel miscible biofuel. The biochar will be examined for use as a soil amender for enhanced biomass yields. Advanced analytical techniques to benefit levulinic acid yields will be developed and employed online to allow real-time adjustment of biomass conversion conditions. All of the fuels produced will be tested to ensure compliance with current fuel requirements.

Wong W.,University of Chile | Barba P.,Institute Investigaciones Agropecuarias INIA | Alvarez C.,Institute Investigaciones Agropecuarias INIA | Castro A.,University of Santiago de Chile | And 7 more authors.
Chilean Journal of Agricultural Research | Year: 2010

The transgenic plum (Prunus domestica L.) C5, in which the coat protein (CP) gene of the Plum pox virus (PPV) is inserted, represents a unique example of the use of genetic engineering for fruit crop improvement in Prunus spp. Field trials in Poland, Romania, and Spain have demonstrated resistance of C5 to several D and M strain PPV isolates. In Chile, the quarantine regulations for PPV and for genetically modified (GM) plants require that the testing of C5 for resistance to Chilean PPV isolates be done under controlled isolated conditions. To carry out these tests C5 shoots were multiplied in vitro and micro-grafted onto four Adesoto101 (Prunus insititia L.) rootstock populations that had been previously infected each with one of four Chilean PPV-Ds. Tests were carried out under controlled conditions in a biosafety greenhouse. Symptoms appearance, virus detection, and viral mRNA levels for the cylindrical inclusion (CI) and CP genes were determined during three consecutive growing seasons. Complete resistance to all PPV isolates was demonstrated during the first 2 yr in all of the C5 plants. In the third season, four of 10 C5 plants showed mild symptoms on leaves close to the graft union and low but detectable CI mRNA levels in the C5 scions. These results support the effectiveness of using of micro-grafting on P. insititia for PPV resistance studies, especially in the limited space of a quarantine facility; whereas resistance levels in C5 after 3 yr indicate the importance of long term and field scale evaluations. Source

Olate V.R.,University of Talca | Nachtigall F.M.,Fraunhofer Chile Research | Santos L.S.,University of Talca | Santos L.S.,Fraunhofer Chile Research | And 7 more authors.
Journal of Mass Spectrometry | Year: 2016

Piscirickettsia salmonis is a pathogenic bacteria known as the aetiological agent of the salmonid rickettsial syndrome and causes a high mortality in farmed salmonid fishes. Detection of P. salmonis in farmed fishes is based mainly on molecular biology and immunohistochemistry techniques. These techniques are in most of the cases expensive and time consuming. In the search of new alternatives to detect the presence of P. salmonis in salmonid fishes, this work proposed the use of MALDI-TOF-MS to compare serum protein profiles from Salmo salar fish, including experimentally infected and non-infected fishes using principal component analysis (PCA). Samples were obtained from a controlled bioassay where S. salar was challenged with P. salmonis in a cohabitation model and classified according to the presence or absence of the bacteria by real time PCR analysis. MALDI spectra of the fish serum samples showed differences in its serum protein composition. These differences were corroborated with PCA analysis. The results demonstrated that the use of both MALDI-TOF-MS and PCA represents a useful tool to discriminate the fish status through the analysis of salmonid serum samples. © 2016 John Wiley & Sons, Ltd. Source

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