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101.
Staffieri F De Monte V De Marzo C Grasso S Crovace A 《Veterinary anaesthesia and analgesia》2010,37(6):483-490
ObjectiveTo compare the effects of two fractions of inspired oxygen (FiO2) (0.4 and 1) on lung aeration and gas exchange during general anaesthesia in cats.Study designRandomized, blinded, controlled study.AnimalsThirty healthy, mixed breed, client owned female cats.Materials and methodsCats were premedicated intramuscularly with acepromazine (0.03 mg kg?1) and medetomidine (0.015 mg kg?1). Anaesthesia was induced with propofol (5 mg kg?1) and, after orotracheal intubation, maintained with isoflurane carried by either 100% oxygen (G100, n = 15) or an oxygen-air mixture with 40% oxygen (G40, n = 15). All cats were placed in dorsal recumbency and breathed spontaneously throughout the entire procedure. Following surgery (ovariectomy), a spiral computed tomography (CT) of the thorax was performed, arterial oxygen (PaO2) and carbon dioxide (PaCO2) tensions were measured and alveolar-arterial gradient of oxygen [P(A-a)O2] calculated. The CT images were analysed for lung aeration by the analysis of radiograph attenuations (Hounsfield units, HU), according to the following classification: hyperinflated area (-1000 to -900 HU), normally aerated area (-900 to -500 HU), poorly aerated area (-500 to -100 HU) and non-aerated area (-100 to +100 HU). The groups were compared using one-way anova.ResultsCompared to G100, the normally-aerated lung area was significantly greater and the poorly-aerated and non-aerated areas were significantly smaller in G40. PaCO2 was similar in both groups. PaO2 and P(A-a)O2 were significantly higher in G100. In both groups, pulmonary atelectasis developed preferentially in the caudal lung fields.ConclusionIn cats anaesthetised with isoflurane, the administration of an FiO2 of >0.9 significantly impaired lung aeration and gas exchange as compared to an FiO2 of 0.4.Clinical relevanceAn FiO2 of 0.4 may better preserve lung aeration and gas exchange in anaesthetised spontaneously breathing cats but monitoring is essential to ensure oxygenation is adequate. 相似文献
102.
Closed cycle soilless techniques can be adopted to minimize water and fertilizer losses in greenhouse cultivation. There is a general lack of information regarding the soilless cultivation of vegetables with closed cycle subirrigation techniques, specifically when using saline water. In this study, a trough bench subirrigation system (SUB), with two fertilizer concentrations (“100%”, containing 9.8 mol m−3 N-NO3, 1.6 mol m−3 P-H2PO4, 8.7 mol m−3 K+, 2.8 mol m−3 Ca+, 1.8 mol m−3 Mg+, 4 mol m−3 S-SO4, and “70%”, containing 70% of the macronutrient concentration) in the nutrient solution (NS), was compared with open cycle drip-irrigation (DRIP with “100%” NS). For all the three treatments, NS was prepared using rain water (0.05 dS m−1) and adding NaCl (1 g L−1), in order to simulate moderate saline irrigation water. The effect of the treatments on tomato (Solanum lycopersicum L.) plant growth, yield, fruit quality, water use efficiency (WUE) and fertilizer consumption was evaluated. Substrate and recirculating NS composition were also studied. Subirrigation, regardless of NS concentration, reduced plant height (by 30 cm), leaf area (by 1411 cm2), total fresh and dry weight (by 429 and 48.5 g plant−1, respectively) but not dry matter percentage of the whole plant, with respect to DRIP. Yield was reduced when plants were subirrigated with the higher concentrated NS, but no differences with open cycle DRIP were recorded when the lower NS concentration was used in SUB. Fruit quality was not affected by irrigation system or NS concentration. The higher WUE was obtained with subirrigation. NaCl accumulated similarly over the crop cycle in recirculating NS of both SUB treatments and in growing substrates of all the three treatments. Higher salt concentration was found in subirrigated substrates, in particular in the upper part of the substrate profile. Fertilizers accumulated in the subirrigated substrates when the higher NS concentration was used, but not when the NS concentration was reduced by 30%. The results of this study indicate that tomato can be grown successfully in a closed cycle subirrigation system, using saline water, by reducing the fertilizer NS concentration normally used with traditional open cycle systems. 相似文献
103.
104.
Thibaut Olivier Vaidevutis Šveikauskas Elisabeth Demonty Kris De Jonghe Pascal Gentit Mojca Viršček-Marn Sabine Grausgruber-Gröger Sébastien Morio Francesco Faggioli Michèle Visage Frédéric Fauche Maria Gusina Marta Luigi Helena Lasner Irena Mavrič-Pleško 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(3):645-654
105.
Dietary Supplementation of Oregano and Sage Dried Leaves on Performances and Meat Quality of Rabbits
Luca Rotolo Francesco Gai Silvana Nicola Ivo Zoccarato Alberto Brugiapaglia Laura Gasco 《农业科学学报》2013,12(11):1937-1945
The aim of this research was to evaluate the dietary supplementation 1% (w/w) of oregano and sage dried leaves on performances and meat quality of broiler rabbits. A feeding trial, which lasted 48 d, was carried out on 105 male Bianca Italiana rabbits randomly divided in seven groups and fed ad libitum. At the end of the trial ten animals per group were slaughtered and samples of dorsal muscle were taken in order to perform laboratory analysis. Mortality rate did not statistically differ between groups. Growth performances of animals fed diets supplemented with aromatic plants were higher (P〈0.05) than those of animals of control group, whereas carcass parameters were not affected by treatments excepting for the slaughter weight that showed the same trend as growth performances. Meat quality traits, oxidative lipid stability and fatty acid proifle were not inlfuenced by aromatic plant supplementation. In conclusion, oregano and sage in form of dried leaves can be used in rabbit without adverse effects on performance, carcass characteristics and meat quality traits. 相似文献
106.
Translating land cover/land use classifications to habitat taxonomies for landscape monitoring: a Mediterranean assessment 总被引:1,自引:1,他引:0
107.
Guido Cipriani Francesco Pinosa Maura Bonoli Walter Faedi 《The Journal of Horticultural Science and Biotechnology》2013,88(4):668-675
SummaryThis study reports the development of 68 new microsatellite markers. Of these, 45 were obtained, together with 20 others already published, from an AC-enriched genomic library of the wild strawberry Fragaria vesca. The 68 markers were tested for transportability to the cultivated strawberry F. ananassa ‘Miss’ and 83% gave positive amplifications. Twenty pairs of primers were selected and tested for their transportability to 16 Fragaria taxa and eight species of Rosaceae (peach, almond, apricot, European and Sino-Japanese plums, sweet and sour cherry, apple). The average proportion of primers amplifying loci in Fragaria was 69%, while the transportability to Rosaceae was very low and resulted in null amplification for 80% of the primer pairs. In addition, 23 microsatellite markers were developed from F. ananassa ‘expressed sequence tags’ databases. A total of 141 primer pairs from these and published primers, were tested for polymorphism in the two parents (91.333.2 and ‘Snovit’; both belonging to F. vesca) of a full sib population of 46 individuals. Fifty-eight percent of the primers were discarded because they were monomorphic, or were difficult to interpret, or their allelic conformation was not useful for mapping. The segregation of 73 primers was tested in the progeny and a partial map of the female parent was constructed, based on the segregation of 66 useful markers that were ordered into eight linkage groups of which four had from seven to 14 markers. 相似文献
108.
Francesco Spinelli Giovanni Fiori Massimo Noferini Mattia Sprocatti Guglielmo Costa 《The Journal of Horticultural Science and Biotechnology》2013,88(6):131-137
SummaryAlternate bearing is a serious problem in many apple varieties. In fact, each year, apple trees have to be thinned in order to ensure a correct and constant balance between the reproductive and vegetative tendencies of the plant. In organic fruit growing, there is no alternative to the expensive and time-consuming process of hand-thinning. Under these conditions, the use of natural bio-stimulants which enhance the efficiency of nutrient uptake, plant fitness to different pedoclimatic conditions, and plant tolerance to stress, offers new opportunities to reduce the negative effects of alternate bearing. The aim of this work was to evaluate the effects of Actiwave®, a metabolic enhancer derived from the alga, Ascophillum nodosum, on ‘Fuji’ apple trees affected by experimentally-imposed alternate bearing. The experiments were carried in open field conditions over four consecutive years. Although the effect of Actiwave® was erratic from year-to-year, the compound generally reduced those problems linked to alternate bearing. Actiwave® had its most significant effect on alternate bearing plants that were also affected by nutrient deprivation due to the absence of fertilisation. In these trees,Actiwave® decreased the oscillations in yield between “on” and “off” years and increased the average fruit weight on plants affected by too-high a crop load. Treated trees also showed higher leaf chlorophyll contents (increased by 12%), with a consequent increase in the rates of photosynthesis and respiration. On the other hand, under standard conditions, in well-fertilised balanced plants, Actiwave® did not have any significant effect. This evidence corroborates the hypothesis that Actiwave® may be a useful tool to reduce alternate bearing in organic and low-input farming. 相似文献
109.
Francesco Rovero Arafat S. Mtui Amani S. Kitegile Martin R. Nielsen 《Biological conservation》2012,146(1):89-96
Hunting and habitat degradation are universal threats to primates across the tropics, thus deciphering the relative impact of threats on population relative abundance is critical to predicting extinction risk and providing conservation recommendations. We studied diurnal primates over a period of nearly 6 years in the Udzungwa Mountains of Tanzania, a site of global importance for primate conservation. We assessed how population relative abundance of five species (of which two are endemic and IUCN-Endangered) differed between two forest blocks that are similar in size and habitat types but contrast strongly in protection level, and how abundance changed during 2004–2009. We also measured habitat and disturbance parameters and, in the unprotected forest, evaluated hunting practices. We found significant differences in primates’ abundance between protected and unprotected forests, with the greater contrast being the lower abundance of colobine monkeys (Udzungwa red colobus and Angolan colobus) in the unprotected forest. At this site moreover, colobines declined to near-extinction over the study period. In contrast, two cercopithecines (Sanje mangabey and Sykes’ monkey) showed slightly higher abundance in the unprotected forest and did not decline significantly. We argue that escalating hunting in the unprotected forest has specifically impacted the canopy-dwelling colobus monkeys, although habitat degradation may also have reduced their abundance. In contrast, cercopithecines did not seem affected by the current hunting, and their greater ecological adaptability may explain the relatively higher abundance in the unprotected forest. We provide recommendations towards the long-term protection of the area. 相似文献
110.
Sattar A Rubessa M Di Francesco S Longobardi V Di Palo R Zicarelli L Campanile G Gasparrini B 《Reproduction in domestic animals》2011,46(6):1090-1097
The objectives of this work were to evaluate whether the sperm penetration speed is correlated to the in vitro fertility and whether adapting the gamete co-incubation length to the kinetics of the bull improves in vitro fertility and affects the sex ratio. In vitro matured oocytes were co-incubated with spermatozoa from four different bulls (A-D). At various post-insemination (p.i.) times (4, 8, 12, 16 and 20 h), samples of oocytes were fixed and stained with DAPI for nuclei examination, while the remaining ones were transferred into culture to evaluate embryo development. The blastocysts produced were sexed by PCR. Two bulls (A and B) had faster kinetics than the others (C and D), as shown by the higher penetration rates recorded at 4 h p.i. (43%, 30%, 11% and 6%, respectively for bulls A, B, C and D; p<0.01). The differences in the kinetics among bulls did not reflect their in vitro fertility. The incidence of polyspermy was higher for faster penetrating bulls (36%, 24%, 16% and 4%, respectively for bulls A, B, C and D; p<0.01) and at longer co-incubation times (0%, 16%, 19%, 30% and 34%, respectively at 4, 8, 12, 16 and 20 h p.i.; p<0.01). The fertilizing ability of individual bulls may be improved by adapting the co-incubation length to their penetration speed. A sperm-oocyte co-incubation length of 8 h ensured the greatest blastocyst yields for the two faster penetrating bulls. On the contrary, 16 h co-incubation was required to increase (p<0.01) cleavage rate of the two slower bulls. Bulls with a faster kinetics did not alter the embryo sex ratio towards males. The female/male (F/M) ratios recorded were 2.1, 1.4, 1.2, 1.3 and 1.6, respectively at 4, 8, 12, 16 and 20 h p.i. 相似文献