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81.
Stefano Ponte 《Agriculture and Human Values》2007,24(2):179-193
Contemporary regulation of food safety incorporates principles of quality management and systemic performance objectives that
used to characterize private standards. Conversely, private standards are covering ground that used to be the realm of regulation.
The nature of the two is becoming increasingly indistinguishable. The case study of the Ugandan fish export industry highlights
how management methods borrowed from private standards can be applied to public regulation to achieve seemingly conflicting
objectives. In the late 1990s, the EU imposed repeated bans on fish imported from Uganda on the basis of food safety concerns.
However, the EU did not provide scientific proof that the fish were actually “unsafe.” Rather, the poor performance of Uganda’s
regulatory and monitoring system was used as justification. Only by fixing “the system” (of regulations and inspections) and
performing the ritual of laboratory testing for all consignments for export to the EU did the Ugandan industry regain its
status as a “safe” source of fish. Yet, gaps and inconsistencies abound in the current Ugandan fish safety management system.
Some operations are by necessity carried out as “rituals of verification.” Given the importance of microbiological tests and
laboratories in the compliance system, “alchemic rituals” provide an appropriate metaphor. These rituals are part and parcel
of a model that reassures the EU fish-eating public that all is under control in Uganda from boat to point of export. As a
consequence, actual non-compliance from boat to landing site allows the fishery to survive as an artisanal operation.
Stefano Ponte
is Senior Researcher at the Danish Institute for International Studies, Copenhagen. His research focuses on the role of standards,
regulation and quality conventions in the governance of agro-food value chains, with particular focus on Africa. He is co-author
of Trading Down: Africa, Value Chains and the Global Economy and The Coffee Paradox: Global Markets, Commodity Trade and the
Elusive Promise of Development. 相似文献
82.
Früh-Green GL Kelley DS Bernasconi SM Karson JA Ludwig KA Butterfield DA Boschi C Proskurowski G 《Science (New York, N.Y.)》2003,301(5632):495-498
Strontium, carbon, and oxygen isotope data and radiocarbon ages document at least 30,000 years of hydrothermal activity driven by serpentinization reactions at Lost City. Serpentinization beneath this off-axis field is estimated to occur at a minimum rate of 1.2 x 10(-4) cubic kilometers per year. The access of seawater to relatively cool, fresh peridotite, coupled with faulting, volumetric expansion, and mass wasting processes, are crucial to sustain such systems. The amount of heat produced by serpentinization of peridotite massifs, typical of slow and ultraslow spreading environments, has the potential to drive Lost City-type systems for hundreds of thousands, possibly millions, of years. 相似文献
83.
Stefano Carbonara Raffaele D'Adamo Andrea Novelli Sergio Pelosi Adele Fabbrocini 《Aquaculture Research》2019,50(9):2469-2476
The development of sustainable methods for sea urchin juvenile production is currently constrained by high mortality rates during larval growth and the high costs of larval rearing systems management. With the aim of developing a method for the production of juveniles of the purple sea urchin Paracentrotus lividus in a medium‐scale recirculating system, the present study focused on the effects of high stocking densities on larval growth. Plutei larvae were reared at three different densities (up to 7 ind/ml) in a semi‐static culture system. Larval survival and metamorphosis success were evaluated in order to identify the most effective density range. The highest metamorphosis rates (80%–95%) were obtained at 4 and 7 larvae/ml. These results are comparable with (and in some cases higher than) those reported for the same species at much lower larval densities. In conclusion, the rearing conditions tested here show for the first time that a significantly higher (4 ind/ml) stocking density than those of traditional P. lividus rearing methods (based on large volumes and low densities) can be adopted, thus supporting the feasibility of an increase in the final output of competent larvae with no increase in rearing volumes. 相似文献
84.
85.
Filippo Bargnesi Stefano Gridelli Carlo Cerrano Francesco Ferretti 《水产资源保护:海洋与淡水生态系统》2020,30(5):915-927
- Sharks are globally exposed to several anthropogenic threats, which, in many cases, have severely reduced their distribution and have impacted populations. In the Mediterranean Sea, because of its long history of exploitation and the relatively short span of scientific monitoring, reconstructing shark baselines is challenging. Many vulnerable species declined in population abundance and geographic distribution before it was possible to adequately track these changes. Consequently, for many of these species, current conservation assessments are now suffering from a severe case of shifting baseline syndrome, whereby their historical occurrence in the area is questioned.
- The sand tiger shark (Carcharias taurus) is one of these cases. Characterized by high philopatry, restricted home range, and low interchange between populations, its Mediterranean population may have been severely impacted by the high historical fishing pressure in the region before scientific monitoring began.
- In this study, the history of the abundance and distribution of C. taurus in the Mediterranean Sea was reconstructed through a comprehensive search of occurrence records in the literature and in museum collections. Between 1810 and 2008, 31 occurrence records and 54 publications provided information on the presence of the species in the area. These records were sparse but systematic over time and indicated occurrence hot spots in the south‐western Mediterranean Sea and in the eastern Adriatic Sea.
- The presence of ten sightings of juveniles from a total of 18 sightings with length information suggested local parturition. Habitat and extinction models indicate that the area has suitable oceanographic conditions for the occurrence of the species and that the species cannot be considered extinct in the Mediterranean Sea. Our study suggests that there is still hope for the recovery of the species and underlines the crucial role of historical investigations to reconstruct the history of large elasmobranchs in the Mediterranean Sea.
86.
Stefano Peruzzi Anne Kettunen Raul Primicerio & Goran Kauri 《Aquaculture Research》2007,38(9):926-932
The effects of thermal treatments on induction of triploidy in Atlantic cod have been investigated. Cold shock [−1.7±0.1°C at 20 min post fertilization (PF) for 2 h] was based on a previously developed protocol, and heat shocks, below the lethal threshold of 24°C, were at 16, 18 or 20°C applied 20, 30 or 40 min PF for 20 min. Cold shock did not affect larval survival and was ineffective for producing triploids (range 0–4%). A heat shock of 20°C at 20 min PF generated the highest percentages (range 66–100%) of triploid larvae at hatching, with survival ranging from 10% to 20% relative to the controls. Lower heat shock temperatures or delayed shocks increased survival but decreased the number of triploids, providing no net gain in triploid yield (range 1–9%). Heat shocks applied later than 20 min PF produced 2–4% tetraploid larvae at hatching. A thermal shock of 20°C initiated at 20 min PF and lasting 20 min proved to be the most generally efficient treatment for induction of triploidy in Atlantic cod. 相似文献
87.
Attilio L. Mordenti Nico Brogna Giorgia Canestrari Elena Bonfante Stefano Eusebi Ludovica M. E. Mammi Elisa Giaretta Andrea Formigoni 《Animal Science Journal》2019,90(5):619-627
Focus of this study was to evaluate the most suitable breed/crossbred and the appropriate nutritional strategies to increase marbling in beef muscle and to improve its healthy properties, in particular the n‐3 fatty acids content. One hundred and seventy‐six heifers of three crossbreed commonly reared by Emilia‐Romagna farmers: 48 Bleu Belge × Freisian (ITA), 48 Charolais × Aubrac (FRA), and 80 Angus (ANG) were used. Animals of each breed were randomly subdivided in two experimental groups that received two diets, differing for the dietary lipid source. Control group (C) received a basal diet containing protected vegetable fats, whereas treated one (T) received the same basal diet supplemented with 0.9 kg/head/day of extruded flaxseed. After slaughtering, a sample of Longissimus thoracis was collected from each animal for meat quality analysis. Our results demonstrated that, in a shorter fattening period, ANG animals obtained the best dry matter intake, average daily gain and the best fattening scores. ITA and ANG meat presented the highest marbling scores. ANG breed had the highest amount of C18:1, the highest unsaturated/saturated fatty acids ratio and the lowest n‐6/n‐3 ratio. The T animals, independently from breed, showed the highest amount of α‐linolenic acid (ALA). In addition, ANG‐T meat presented the highest ALA content. 相似文献
88.
Trends in the quality and hygiene parameters of bulk Italian Mediterranean buffalo (Bubalus bubalis) milk: A three year study 下载免费PDF全文
Marina Pasquini Andrea Osimani Stefano Tavoletti Itzhak Moreno Francesca Clementi Maria Federica Trombetta 《Animal Science Journal》2018,89(1):176-185
Buffalo milk represents an indispensable source of nourishment in many parts of the world and it is the second most consumed milk worldwide. Buffalo milk is actually used for the production of many dairy products such as pasteurized or concentrated milk, butter, yogurt, ice‐cream, dehydrated milk products and cheeses. Due to its high nutritional value and the presence of natural bioactive substances, buffalo milk can also provide health benefits to consumers. In Italy, buffalo milk is used mainly for cheese making, mozzarella PDO (Protected Designation of Origin), which is a highly valued dairy product. This 3‐year study, carried out between 2011 and 2013, was aimed at evaluating the quality of bulk Italian Mediterranean buffalo milk by monitoring physico‐chemical parameters, somatic cell and total bacterial counts. A total of 51 samples of bulk milk were collected from one herd throughout the monitored period. Analysis of variance, carried out to test month, season and year main effects, highlighted remarkable seasonal effects for fat, protein and lactose content, as well as for predicted mozzarella cheese yield, and somatic cell counts. The calculation of simple correlations allowed the identification of positive correlations between estimated cheese yield and fat and protein content. 相似文献
89.
Paltrinieri S Comazzi S Ceciliani F Prohaska R Bonfanti U 《Veterinary journal (London, England : 1997)》2007,173(1):200-203
Stomatocytosis resembles human overhydrated hereditary stomatocytosis (OHSt), a disease characterised by a reduced or absent stomatin expression. The objective of this report was to investigate the expression level of stomatin in erythrocytes from Standard Schnauzers with stomatocytosis. Routine haematology, intraerythrocytic Na(+)/K(+) concentration and stomatin expression were evaluated in blood from twelve Standard Schnauzers and from three controls. SDS-PAGE and Western blotting on isolated integral membrane proteins were used to investigate stomatin expression. Circulating stomatocytes, macrocytosis, anisocytosis, increased erythrocyte fragility and high intracellular sodium and potassium concentrations were found in 10/12 dogs from the same breeding line although stomatin levels were similar to those of controls. In spite of the clinico-pathological similarities between human and canine stomatocytosis, erythrocytes from affected dogs do not lack stomatin and the expression level of this protein cannot therefore be used to diagnose hereditary stomatocytosis in Standard Schnauzers. 相似文献
90.