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231.
M. Cecilia N. Nunes Jean-Pierre Emond Sharon Dea Yavuz Yagiz 《Postharvest Biology and Technology》2011,59(3):280-288
During distribution and retail display, fruits and vegetables are often exposed to undesirable temperature and humidity conditions which often result in increased waste due to weight loss and objectionable appearance. Unwaxed fresh-market slicing cucumbers (cv. Calypso) were harvested from a commercial operation and shipped to a distribution center (DC) in Florida. At the DC, 2 d after harvest, cucumbers were sorted and either commercially machine packaged in expanded polystyrene trays covered with a polyvinylchloride film or remained unpackaged for bulk retail display. Cucumbers were transported the next day by truck to a retail store in Gainesville, collected from the store, and stored under optimum (10 °C and 90% RH) or simulated retail display conditions (4 °C or 14 °C and 90–92% RH). Sensory (visual and instrumental color, firmness, shriveling, chilling injury and decay) and compositional quality (pH, titratable acidity, soluble solids and chlorophyll contents) were evaluated initially at the DC and after a 4-d simulated retail display period. Overall, bulk cucumbers were softer, appeared more shriveled, and were more affected by pitting and decay than packaged cucumbers. Bulk cucumbers also appeared lighter green and more yellowish than packaged fruit. Hue angle was less in bulk than in packaged cucumbers, but no consistent differences were observed in the L*, chroma, and hue values between the different temperatures. Small variations in the L*, hue, and chroma values compared to significant losses in chlorophyll content suggest that insufficient chlorophyll degradation occurred to cause major visual color changes. The greater weight loss in bulk cucumbers compared to packaged fruit was associated with accelerated chlorophyll degradation, lower acidity, and lower soluble solids content. Although packaged cucumbers had better visual quality than bulk cucumbers, there was higher RH inside the packages and greater development of decay on packaged fruit. Overall, after the 4-d simulated retail display, the appearance of the cucumbers used in this study was considered to be objectionable due to either yellowing, loss of firmness, shriveling or decay, regardless of the treatment. Results from this study demonstrate the importance of using an appropriate protective package in addition to maintaining the optimum temperature during distribution and retail display. Moreover, initial quality evaluation should be performed upon reception at the DC, and before cucumbers are displayed at the retail store, in order to estimate the remaining shelf life before this product becomes unacceptable for sale. 相似文献
232.
233.
Alfredo Gravina José Cataldo Giuliana Gambetta Elisa Pardo Cecilia Fornero Sebastián Galiger Rodolfo Pienika 《Scientia Horticulturae》2011
Peel damage originated by wind is the main abiotic cause of citrus fruit discards for export in Uruguay. Natural windbreaks such as Eucalyptus and Casuarinas have not been effective in reducing it. This research was carried out during three years in a citrus orchard situated in the coastal plain of Uruguay (35° SL). The purpose of this work was to study wind climate inside the orchard, fruit seasonal sensitivity, basal leaf effect on the onset and evolution of peel damage, and the efficiency of artificial windbreaks to reduce fruit discard of ‘Ellendale’ tangor. Average wind velocity in the orchard did not exceed 5 m s−1. First peel scars were evident two weeks after petal fall and damaged fruit percentage importantly increased during the first stage of fruit growth. Low energy vortexes caused almost permanent friction between basal leaves and the developing fruitlets growing in their axil. Removal of the basal leaf decreased significantly wind damaged fruit. Natural wind flow modification through the use of semi-porous artificial windbreak nets (5 cm by 10 cm mesh) modified low energy vortexes and increased significantly the percentage of export quality fruit. We conclude that this type of net is more efficient than natural windbreaks or classical nets to reduce wind damage in citrus fruit. 相似文献
234.
Cecilia I. Perez-Moreno Laurent L. Cou?til Suzanne M. Pratt Hugo G. Ochoa-Acu?a Rose E. Raskin Mark A. Russell 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(8):821-827
The objective was to quantify the effect of furosemide and carbazochrome on exercise-induced pulmonary hemorrhage (EIPH) in Standardbred horses using red blood cell count and hemoglobin concentration in bronchoalveolar lavage (BAL) fluid. Six healthy Standardbred horses with prior evidence of EIPH performed a standardized treadmill test 4 h after administration of placebo, furosemide, or furosemide–carbazochrome combination. Red blood cell (RBC) counts and hemoglobin concentrations were determined on the BAL fluid. The RBC count in BAL ranges were (2903–26 025 cells/μL), (45–24 060 cells/μL), and (905–3045 cells/μL) for placebo, furosemide, and furosemide–carbazochrome, respectively. Hemoglobin concentration ranges were (0.03–0.59 mg/mL), (0.01–0.55 mg/mL), and (0.007–0.16 mg/mL) for placebo, furosemide, and furosemide– carbazochrome groups, respectively. No significant differences were detected among treatments. However, there was great variability among horses, suggesting that a larger sample size or better selection of horses was needed. 相似文献
235.
Cecilia Wolff Ulf Emanuelson Anna Ohlson Stefan Alenius Nils Fall 《Acta veterinaria Scandinavica》2015,57(1)
Background
Infections with bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BoCV) are endemic to the cattle populations in most countries, causing respiratory and/or enteric disease. It has been demonstrated that herds can remain free from these infections for several years also in high prevalence areas. Organically managed (OM) dairy herds have been shown to have lower seroprevalence of both viruses compared to conventionally managed (CM) herds. The objective of this study was to challenge the hypothesis of a lower occurrence of BRSV and BoCV in OM compared to CM dairy herds.In November 2011, May 2012 and May 2013 milk samples from four homebred primiparous cows were collected in 75 to 65 OM and 69 to 62 CM herds. The antibody status regarding BRSV and BoCV was analysed with commercial indirect ELISAs. Herds were classified as positive if at least one individual sample was positive.Results
The prevalence of positive herds ranged from 73.4% to 82.3% for BRSV and from 76.8% to 85.3% for BoCV among OM and CM herds, over the three sampling occasions. There was no statistically significant difference between OM and CM herds at any sampling occasion. The incidence risk of newly infected herds did not differ statistically between OM and CM herds at any sampling occasion, neither for BRSV nor for BoCV. The incidence of herds turning sero-negative between samplings corresponded to the incidence of newly infected. Bulk tank milk (BTM) samples were also sampled in the herds and analysed. Several herds were negative on individual samples but positive in BTM. Herd-level data on production, health and reproduction were retrieved from VÄXA Sweden and the study herds were representative of the source population.Conclusion
There was no difference in prevalence of or incidence risk for BRSV or BoCV between Swedish OM and CM herds. Because the incidence of herds becoming seropositive was balanced by herds becoming seronegative it should be possible to lower the prevalence of these two infections among Swedish dairy cattle herds if biosecurity is improved.Electronic supplementary material
The online version of this article (doi:10.1186/s13028-014-0091-x) contains supplementary material, which is available to authorized users. 相似文献236.
Maria Viketoft Björn Sohlenius Cecilia Palmborg Matty P. Berg 《Soil biology & biochemistry》2011,43(5):1063-1070
We report here on an 8-year study examining links between plant and nematode communities in a grassland plant diversity experiment, located in the north of Sweden on previous agricultural soil. The examined plots contained 1, 4 and 12 common grassland plant species from three functional groups; grasses, legumes and forbs. The same plant species composition was maintained in the plots through weeding and resowing during the experimental period. The hypotheses were (i) that the nematode community would shift towards a more diverse and mature fauna over time and (ii) that the effects of both plant species identity and plant species richness would increase over time. As hypothesized, the Bongers’ Maturity Index (a measure of nematode responses to disturbance) increased over time, but not nematode diversity. Instead, the nematode community development in the present grassland experiment seemed to be more characterized by shifts in dominance patterns than by colonization of new taxa. Clear temporal trends were found for plant-feeders and Adenophorea bacterial-feeders which increased in abundance over time in almost all plant treatments. Rhabditidae bacterial-feeders decreased in abundance over time, in particular in plots with legumes. Fungal-feeders, omnivores/predators and the two nematode indices PPI (Bongers’ Plant Parasitic Index) and NCR (Nematode Channel Ratio) had significant interactions between plant composition and time giving some support to our second hypothesis. Our results highlight the need for long-term experiments to examine plant species effects on soil fauna, especially on taxa belonging to higher trophic levels. The results also stress the importance of plant composition for belowground soil faunal communities. 相似文献
237.
Resquin Fernando Navarro-Cerrillo Rafael M. Carrasco-Letelier Leónidas Rachid-Casnati Cecilia 《New Forests》2020,51(4):631-655
New Forests - According to some studies, the use of forest biomass for the generation of electric power and/or heat would result in a significant reduction in the emission of greenhouse gases. This... 相似文献
238.
Use of big bale silage and haylage can be difficult on farms where daily forage consumption is comparatively low as speed of deterioration of forage after bale opening may be faster than feed-out rate. Production of smaller bales at harvest is possible, but expensive and work-intensive. Therefore, a pilot study of rebaling forage stored in big bales to smaller bales was conducted. Three separate experiments were included, where microbial and chemical composition of silage and haylage was studied before and after rebaling. In Experiment III, residual big bale forage stored and opened together with rebaled forage was included. Results showed that rebaled haylage and silage had higher yeast counts compared to initial forage; however, residual bales in Experiment III had yeast counts similar to rebaled forage, indicating an effect of storage time rather than of rebaling. In Experiment II, mould counts were higher in rebaled compared to initial silage, but not in haylage. Chemical composition was similar in initial and rebaled forage except for ammonia-N. In Experiment III, ammonia-N was higher in rebaled compared to initial and residual forage and was the only chemical variable affected by rebaling. Bale temperature during aerobic storage followed ambient temperature until day 6–8 in Experiment I and until day 14 in Experiment III where ambient temperature was lower. In conclusion, rebaling can be done without large changes in chemical composition of the forage, but yeast and mould counts may be higher in rebaled forage, and this risk should be considered when using this procedure. 相似文献
239.
Herrero-Jáuregui Cristina Arnaiz-Schmitz Cecilia Herrera Lorena Smart Simon M. Montes Carlos Pineda Francisco D. Schmitz Maria Fe 《Landscape Ecology》2019,34(7):1525-1545
Landscape Ecology - Urban–rural gradients provide a suitable framework for studying the provision of urban and rural ecosystem services (ES), linked to social welfare. Landscape structure... 相似文献
240.
Fitzroya cupressoides (Cupressaceae) is an endemic and long-lived conifer of southern Chile and Argentina (40–43° S). This species has been subject to continuous exploitation since the 16th century, causing extensive population decline. Historically, the main labour force for the exploitation of F. cupressoides (alerce) was the indigenous Mapuche-Huilliche population, first under the command of the Spanish settlers and later, of non-indigenous Chileans. In coastal forests, timber of alerce has been harvested by Huilliche communities as well as by Chilean and international forestry companies. Records of the regeneration of this pioneer tree after exploitation in the Andean mountains have generally shown limited regeneration depending on the intensity of harvest. Because indigenous exploitation does not use machinery for timber harvesting, and is supposedly less utilitarian than commercial harvest, I propose that areas in the Coastal Range harvested by Huilliche communities should present higher regeneration of alerce than areas harvested by forestry companies. To test this hypothesis, I sampled 10 stands harvested and abandoned by forestry companies and 10 stands harvested by Huilliche communities in the coastal range of the Osorno Province (41° S, 400–800 m). In each stand, I estimated the density of regeneration (sapling stage), number of stumps, number of live adults, and the number of standing and fallen dead alerce. Each stand was characterized by elevation, forest-type, incidence of fire, and vegetation cover. Results showed that forests harvested by Huilliches had higher numbers of live, remnant adult trees with a dbh ≥ 60 cm than forests harvested by timber companies. The number of stumps with a dbh ≥60 cm was significantly higher in stands harvested by timber companies than in Huilliche stands. Despite large differences in sapling densities among stands, regeneration density of alerce was unrelated to the type of harvest used by indigenous people or forestry companies. 相似文献