Replacement of Fish Meal with Soybean Meal,Alone or in Combination with Distiller's Dried Grains with Solubles in Practical Diets for Pacific White Shrimp,Litopenaeus vannamei,Grown in a Clear‐Water Culture System     

Kenneth R. Thompson  Alejandro Velasquez 《Journal of the World Aquaculture Society》2013,44(6):775-785

The objective of this study was to evaluate inclusion of distiller's dried grains with solubles (DDGS) as partial replacement of commercial, solvent‐extracted soybean meal (SBM) in fish meal‐free diets for Pacific white shrimp, Litopenaeus vannamei. Aquaria connected to a recirculating biofiltration system were utilized to evaluate growth, survival, and feed conversion of shrimp during the 8‐wk feeding trial. Each 110‐L aquarium was stocked with 15 shrimp (mean individual weight 0.99 g) and fed one of five diets: a diet containing 20% fish meal (FM), which served as the control (Diet 1); a diet containing 0% FM and 52.5% SBM (Diet 2); and diets containing 0% FM and either 10, 20, or 30% DDGS as partial replacement of SBM (Diets 3, 4, and 5, respectively). Shrimp were fed according to a pre‐determined feeding chart five times daily (0730, 1030, 1330, 1630, and 1930 h) and there were three replicates per dietary treatment. The results from the feeding trial demonstrated that final weight, weight gain (g), and percentage weight gain were significantly higher (P < 0.05) for shrimp fed Diet 1 (10.96 g, 10.01 g, and 1051%, respectively) compared to shrimp fed diets containing DDGS; however, shrimp fed diets containing DDGS had similar (P > 0.05) final weight, weight gain (g), and percentage weight gain as shrimp fed a diet containing 0% FM and 52.5% SBM (Diet 2). Feed conversion ratio (FCR) of shrimp fed Diet 1 (2.84) was significantly lower (P < 0.05) compared to shrimp fed any other diet. Survival (%) was not different (P > 0.05) among treatments and averaged 77.3% for the study. This study demonstrated that practical shrimp diets containing no FM had an adverse impact on growth performance of white shrimp when grown in a clear‐water system and that further research is needed to refine diet formulations when culturing shrimp in these systems when attempting to feed a diet without FM.  相似文献   

Low UV-C illumination for keeping overall quality of fresh-cut watermelon     

Francisco Artés-Hernández  Pedro A. Robles  Perla A. Gómez  Alejandro Tomás-Callejas  Francisco Artés 《Postharvest Biology and Technology》2010,55(2):114-120

The effects of four pre-packaging UV-C illumination doses (1.6, 2.8, 4.8 and 7.2 kJ m^?2) on quality changes of watermelon cubes stored up to 11 days at 5 °C were studied. Non-treated cubes were used as a control. Higher UV-C doses induced slightly higher CO₂ production throughout the storage period, while no changes in C₂H₄ production were monitored. However, UV-C did not significantly affect the final gas partial pressures within modified atmosphere packages where levels of 3–6 kPa O₂ and 13–17 kPa CO₂ were reached for all treatments. UV-C decreased microbial counts just after illumination. After 11 days at 5 °C, mesophilic, psycrophilic and enterobacteria populations were significantly lower in UV-C treated watermelon. Slight changes in CIE colour parameters were observed. According to sensory quality attributes, control and low UV-C treated cubes (1.6 and 2.8 kJ m^?2) can be stored for up to 11 days at 5 °C while the maximum shelf-life of moderate to high UV-C treated fruit was 8 days at 5 °C. Control cubes showed a 16% decrease in lycopene content after 11 days at 5 °C similar to that found for the high UV-C treatment. However low UV-C treated watermelon cubes preserved their initial lycopene content (2.8 kJ m^?2) or it was slightly decreased (1.6 kJ m^?2). UV-C radiation did not significantly affect the vitamin C content while catalase activity and total polyphenols content considerably declined throughout the storage period. However, total antioxidant capacity markedly increased, independently of UV-C doses. As a main conclusion, UV-C radiation can be considered a promising tool for keeping overall quality of fresh-cut watermelon.  相似文献   

Does recovery planning improve the status of threatened species?     

Madeleine C. Bottrill  Jessica C. Walsh  James E.M. Watson  Liana N. Joseph  Alejandro Ortega-Argueta  Hugh P. Possingham 《Biological conservation》2011,(5):1595-1601

Recovery planning is a key component of government-funded initiatives to address declining populations of threatened species. To date, there has been limited retrospective evaluation on the impact of recovery plans, despite an increasing interest in evaluating recovery planning motivated by demands for greater accountability and a shift away from single-species focused strategies to multi-species, landscape and ecosystem-based plans. In the context of threatened species management in Australia, we aimed to investigate whether listed species with recovery plans are more likely to have improved their status compared to listed species without recovery plans. Since 1999, over 600 draft and approved recovery plans have been developed for more than 850 of 1663 species currently listed threatened species in Australia. We applied a novel econometric matching analysis to reduce biases associated with the non-random selection of species for listing and recovery planning. We found that the presence or absence of a recovery plan did not have a statistically significant effect on whether a species’ status was improving, stable or declining. The result suggests that recovery plans may not be useful in the short term and uncertainty persists about whether or not they make a long term contribution to species recovery. One major contributing factor is the lack of basic accounting of recovery planning efforts. This limits our ability to refute or confirm the impact of recovery planning on species status, and has the potential to reduce public confidence in government expenditures. Better systems for reporting and evaluation are therefore required to promote transparency, improve existing knowledge and facilitate efficient investments in future management actions.  相似文献   

Dietary Intake of Purple Corn Extract Reduces Fat Body Content and Improves Antioxidant Capacity and n‐3 Polyunsaturated Fatty Acid Profile in Plasma of Rainbow Trout,Oncorhynchus mykiss          下载免费PDF全文

Alejandro Villasante  Biswamitra Patro  Boon Chew  Michael Becerra  Jurij Wacyk  Ken Overturf  Madison S. Powell  Ronald W. Hardy 《Journal of the World Aquaculture Society》2015,46(4):381-394

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Dan Brockington,Rosaleen Duffy,and Jim Igoe: Nature unbound: conservation,capitalism and the future of protected areas     

Alejandro Camargo 《Agriculture and Human Values》2014,31(1):159-160

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The espinal: agroforestry systems of the mediterranean — type climate region of Chile     

Carlos Ovalle  James Aronson  Alejandro Del Pozo  Julia Avendano 《Agroforestry Systems》1990,10(3):213-239

The Central Valley of Chile is largely occupied by a pseudo-savanna called espinal consisting of a single dominant tree species, Acacia caven (Mol.) Mol. (Leguminosae), and some 215 annuals, most of which were inadvertently introduced from the Mediterranean Basin. The probable origin and current distribution of the espino (Acacia caven) and the espinales in Chile are described. Predominant production systems of the espinal in both the semiarid and subhumid regions of Chile are outlined, with emphasis on the later region. Causes of the current low levels of productivity are discussed, and various strategies for long-term improvement of the espinal are presented.  相似文献   

Influence of eggs on the aroma composition of a sponge cake and on the aroma release in model studies on flavored sponge cakes     

Pozo-Bayón MA  Ruíz-Rodríguez A  Pernin K  Cayot N 《Journal of agricultural and food chemistry》2007,55(4):1418-1426

The use of solvent-assisted flavor evaporation extraction (SAFE) and purge and trap in Tenax allowed the identification of more than 100 volatile compounds in a sponge cake (SC-e). Gas chromatography-olfactometry (GC-O) of the SAFE extracts of crumb and crust were achieved in order to determine the most potent odorants of SC-e. The change in the traditional dough formulation of SC-e in which eggs were substituted by baking powder (SC-b) as the leavening agent produced important changes in some key aroma compounds. The release curves of some aroma compounds-some of them generated during baking and others added in the dough-were followed by cumulative headspace analysis. In the flavored SC-b, the aroma release curves showed a plateau after 15 min of purge, while the release increased proportionally with the purge time in the flavored SC-e. In general, except for some of the aroma compounds with the highest log P values, the rate of release of most of the added and generated aroma compounds was significantly influenced by the changes in the cake formulation. The higher rates of release found for the aroma compounds in SC-b could contribute to explain its rapid exhaustion of aroma compounds in the purge and trap experiments and might lead to poorer sensorial characteristics of this cake during storage.  相似文献   

The Epidemiology of Caving Injuries in the United States     

Alejandro C. Stella-Watts  Christopher P. Holstege  Jae K. Lee  Nathan P. Charlton 《The Forestry Chronicle》2012,23(3):215-222

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Venturia inaequalis resistance in local Spanish cider apple germplasm under controlled and field conditions     

Alejandro Martínez-Bilbao  Amaya Ortiz-Barredo  Emilio Montesinos  Jesús Murillo 《Euphytica》2012,188(2):273-283

Host resistance is a key method for the integrated management of apple scab caused by Venturia inaequalis, which is one of the most important diseases of apple. Artificial inoculation of 92 cider apple cultivars with a mixed inoculum of V. inaequalis identified 19 weakly resistant and 19 resistant cultivars. Twelve of these resistant cultivars were previously classified as having low susceptibility to fire blight, and four of them showed complete or weak resistance to races (1), (1, 6) and (6, 7, 13) of V. inaequalis. The analysis of a selection of 72 cultivars for 6 years under field conditions identified 14 cultivars that were classified as resistant to apple scab under high disease pressure involving one to six Mills periods of severe risk of infection each year. Eight out of these 14 cultivars previously showed high levels of resistance to fire blight, which would allow the incorporation of genetic resistance in the integrated production of cider apples in Spain through their use in breeding programs.  相似文献   

Differential interactions of virulent and non-virulent H. parasuis strains with na?ve or swine influenza virus pre-infected dendritic cells     

Tufária Mussá  Carolina Rodríguez-Cari?o  Alejandro Sánchez-Chardi  Massimiliano Baratelli  Mar Costa-Hurtado  Lorenzo Fraile  Javier Domínguez  Virginia Aragon  María Montoya 《Veterinary research》2012,43(1):80

Pigs possess a microbiota in the upper respiratory tract that includes Haemophilus parasuis. Pigs are also considered the reservoir of influenza viruses and infection with this virus commonly results in increased impact of bacterial infections, including those by H. parasuis. However, the mechanisms involved in host innate responses towards H. parasuis and their implications in a co-infection with influenza virus are unknown. Therefore, the ability of a non-virulent H. parasuis serovar 3 (SW114) and a virulent serovar 5 (Nagasaki) strains to interact with porcine bone marrow dendritic cells (poBMDC) and their modulation in a co-infection with swine influenza virus (SwIV) H3N2 was examined. At 1 hour post infection (hpi), SW114 interaction with poBMDC was higher than that of Nagasaki, while at 8 hpi both strains showed similar levels of interaction. The co-infection with H3N2 SwIV and either SW114 or Nagasaki induced higher levels of IL-1β, TNF-α, IL-6, IL-12 and IL-10 compared to mock or H3N2 SwIV infection alone. Moreover, IL-12 and IFN-α secretion differentially increased in cells co-infected with H3N2 SwIV and Nagasaki. These results pave the way for understanding the differences in the interaction of non-virulent and virulent strains of H. parasuis with the swine immune system and their modulation in a viral co-infection.  相似文献