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排序方式: 共有178条查询结果,搜索用时 31 毫秒
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A comparison between marine and terrestrial invertebrate meals for mirror carp (Cyprinus carpio) diets: Impact on growth,haematology and health 下载免费PDF全文
Invertebrate meals (e.g. polychaetes and insects) present novel and sustainable high‐quality nutrient sources for use in fish feed formulations. To test this innovative source, an eleven‐week feeding trial was conducted evaluating the effects of replacing the fishmeal (FM) component as an example of a superior protein source (FM CTRL) with ragworm meal (RW, Nereis virens) and/or silkworm pupae (SWP, Bombyx mori) in mirror carp (Cyprinus carpio) diets. Three experimental diets with partial replacement of FM (diets: RW + FM, SWP + FM and RW + SWP + FM) were formulated. All diets were formulated to be iso‐nitrogenous, iso‐lipidic and iso‐energetic. Growth performance and feed utilization indices were assessed, and the feeding trial concluded with the analysis of haematological parameters to provide an indication of carp physiological and health status. Mean weight gain was greatest in mirror carp fed RW + FM (60.83 fish?1 day?1; P < 0.05 vs. all other diets) followed by SWP + FM (40.62 g fish?1 day?1; P < 0.05 vs. all other diets). The least weight gain was achieved in fish fed FM + SWP + RW+ and FM CTRL (34.34 and 33.96 g fish?1 day?1, respectively; not significantly different from each other). Fish fed on RW + FM diet had significantly lower plasma ammonia concentrations than any other dietary groups (P = 0.04). Mirror carp fed on SWP + FM diet (111.52 units mL?1) were observed to have a marked enhancement in alternative complement activity than FM CTRL (79.21 units mL?1, P = 0.041). Both ragworm and silkworm pupae meal present attractive sustainable functional feed component in carp diets, with benefits on enhancing growth performance and specific physiological parameters. 相似文献
3.
Mazzotti F Di Donna L Maiuolo L Napoli A Salerno R Sajjad A Sindona G 《Journal of agricultural and food chemistry》2008,56(1):63-67
A high-throughput mass spectrometric method is presented for the simultaneous detection of Sudan I, II, III, IV, and Para-Red azodyes in foodstuff. The method is based on the use of deuterium-labeled internal standards and atmospheric pressure chemical ionization (APCI) in a triple-quadrupole instrument. The gas-phase breakdown pattern of each labeled and unlabeled analogue displays the naphthoic moiety as a common fragment. The search for the parents of this common species (parent ion scans) allows, by flow injection and in a single run, the evaluation of the presence of each polluting species spiked in typical foodstuffs. A detailed assay of each azodye was performed by LC-APCI and isotope dilution method, through the multiple reaction monitoring approach, using deuterium-labeled internal standards. Sudan dyes can be quantified above the threshold of 10 ppb except for Sudan Para-Red, for which the limit of quantification was 20 ppb, likely due to the different ionization efficiency. 相似文献
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Donna S. Smith Solke H. De Boer 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(3):405-412
A previously published TaqMan PCR test for R. solanacearum race 3 biovar 2 was modified to enable both the validation of negative results and the confirmation of positive results in
a closed-tube system. Negative results were validated through the use of a reaction control plasmid, designated pRB2C2, which
was designed to generate a 94bp product using the same amplimers targeting the primary diagnostic 68bp sequence in R. solanacearum race 3 biovar 2 DNA. SYBR Green was included in the reaction mix to facilitate the identification of post-reaction products
using melt peak analysis. The 94bp reaction control had a melt peak temperature of about 90°C, while the diagnostic target
amplicon had a melt peak temperature of about 83°C; thus positive results could be easily confirmed and distinguished from
the reaction control product. Addition of pRB2C2 at 100 copies per reaction had no effect on the sensitivity of the TaqMan
assay for R. solanacearum race 3 biovar 2, and the modified assay successfully detected R. solanacearum race 3 biovar 2 in infected, asymptomatic tomato stems and leaves as well as in potato tubers and stems. 相似文献
6.
Donna M. White José I. Redondo Alastair R. Mair Fernando Martinez-Taboada 《Veterinary anaesthesia and analgesia》2017,44(5):1076-1084
Objective
The effect of user experience and inflation technique on endotracheal tube cuff pressure using a feline airway simulator.Study design
Prospective, experimental clinical study.Methods
Participants included veterinary students at the beginning (group S1) and end (group S2) of their 2-week anaesthesia rotation and veterinary anaesthetists (group A). The feline airway simulator was designed to simulate an average size feline trachea, intubated with a 4.5 mm low-pressure, high-volume cuffed endotracheal tube, connected to a Bain breathing system with oxygen flow of 2 L minute?1. Participants inflated the on-endotracheal tube cuff by pilot balloon palpation and by instilling the minimum occlusive volume (MOV) required for loss of airway leaks during manual ventilation. Intracuff pressures were measured by manometers obscured to participants and ideally were 20–30 cm H2O. Student t, Fisher exact, and Chi-squared tests were used where appropriate to analyse data (p < 0.05).Results
Participants were 12 students and eight anaesthetists. Measured intracuff pressures for palpation and MOV, respectively, were 19 ± 12 and 29 ± 19 cm H2O for group S1, 10 ± 5 and 20 ± 11 cm H2O for group S2 and 13 ± 6 and 29 ± 18 cm H2O for group A. All groups performed poorly at achieving intracuff pressures within the ideal range. There was no significant difference in intracuff pressures between techniques. Students administered lower (p = 0.02) intracuff pressures using palpation after their training.Conclusions and clinical relevance
When using palpation and MOV for cuff inflation operators rarely achieved optimal intracuff pressures. Experience had no effect on this skill and, as such, a cuff manometer is recommended. 相似文献7.
Omar Varela Mariana Varas Donna Rattalino Franco Crabbè Mariano Ordano 《Arid Land Research and Management》2017,31(4):418-430
In deserts, shrubs determine landscape structure and influence plant productivity by creating nutrient-enriched environments. Attributes vary among shrub species, thus their contribution to soil characteristics is expected to vary as well, and nutrient input under shrub cover will depend on species attributes. We propose that plant size determines the contribution to soil chemical characteristics. Therefore, the contribution of larger species will be higher than smaller ones. Also, each species will contribute differentially for each chemical parameter. To corroborate these premises, we measured six soil chemical characteristics in areas covered by shrubs and in bare soil, as well as among five nurse species, in four sites of the Monte desert (La Rioja, Argentina). A multivariate analysis of variance (MANOVA) indicated significant variation between cover conditions and locations. Supporting previous studies, the presence of shrubs improved soil properties. Chemical concentration between soils under shrubs and bare soils, respectively, showed as mean and (SD) were: carbon(%): 0.82 (0,47), 0.52 (0.22); nitrates (ppm): 33,33 (67,36), 2.63 (0.56); phosphorous(ppm): 16.76 (25.02), 6.56 (1.92); electrical conductivity (dS m?1): 0.24 (0,43), 0.03 (0,02); pH: 6.93 (0.56), 7.62 (0.53); and water content (%): 3,17 (8.94), 2.47 (9.15). Chemical characteristics also varied according to the nurse species. Larger nurse species affected the ensemble of chemical characteristics, after controlling for cover condition and site. Larger plant species (Bulnesia retama, Prosopis torquata, and Zuccagnia punctata) were significantly associated with higher carbon and higher nitrates concentration. These results suggest that soil properties are enhanced by the size of nurse plant species. 相似文献
9.
Donna J. Lee Ronald M. Gordon 《Aquaculture Economics & Management (Blackwell Science)》2013,17(2):83-96
Aquaculture production and invasive species are intricately linked. Invasives enter waterways threatening production, increasing costs, and diminishing grower returns. Live plants and animals introduced for economic production escape their confines and establish in the wild. This paper provides an overview of the dominant issues illustrated with cases from around the world. 相似文献
10.
Rebecca J. Kessler Shelley Rankin Sheri Young Kathleen O'Shea Maria Calabrese Amy Guldin Nicole Lipson Donna A. Oakley Urs Giger 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):29-38
Background: While screening programs have reduced the risk of infectious disease transmission by donors in human and veterinary blood banking, bacterial contamination of blood products has emerged as a major complication in human medicine. Objectives: To describe a Pseudomonas fluorescens (Pf)‐contaminated feline packed RBC (pRBC) unit and experimentally investigate Pf‐contaminated canine pRBCs. Methods: Canine pRBCs were inoculated with Pf‐rich pRBCs from the sentinel feline unit and stored at 4°C or 20°C for 72 hours. Aliquots from the pRBCs were serially evaluated by microscopy, culture, and a eubacterial 16S rRNA real‐time PCR assay. Results: One Pf‐contaminated feline unit turned black after 22 days of storage and was removed from the blood bank; a source was not found, and no other contaminated units were identified. Canine pRBCs spiked with 5 or 25 μL of the sentinel unit became culture‐ and/or 16S PCR‐positive at ≥8 hours at 20°C and 48 hours at 4°C and developed a color change at ≥24 hours. Sensitivity studies indicated that without incubation, inoculation of ≥100 μL Pf‐rich pRBCs was necessary for a positive 16S PCR test result. Conclusions: P. fluorescens grows in stored pRBCs slowly at 4°C and rapidly at 20°C. Screening of blood products for color change, estimating bacterial concentration with microscopy, and 16S PCR testing are simple and fast ways to detect bacteria in stored blood. Aseptic collection, temperature‐controlled storage, and regular visual monitoring of stored units is recommended. Discolored units should not be transfused, but examined for bacterial contamination or other blood product quality problems. 相似文献