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71.
72.
刘理林 《国外畜牧学(猪与禽)》2002,(6):17-18
你喂给你的断奶猪吃的颗粒料是不是很硬或者是碎的?颗粒比较硬的优点是,从饲料厂经过长途运输直到达到饲槽中为止一直都能够保持其物理形态上的完整。然而,我们有充分的理由相信、很硬的颗粒料不是幼猪所喜欢的。 相似文献
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74.
The effect of the inspired oxygen fraction on arterial blood oxygenation in spontaneously breathing,isoflurane anaesthetized horses: a retrospective study 下载免费PDF全文
Stijn Schauvliege Ioannis Savvas Frank Gasthuys 《Veterinary anaesthesia and analgesia》2015,42(3):280-285
ObjectivesTo investigate the influence of two inspired oxygen fractions (FIO2) on the arterial oxygenation in horses anaesthetized with isoflurane.Study DesignRetrospective, case-control clinical study.AnimalsTwo hundred equine patients undergoing non-abdominal surgery (ASA class 1–2), using a standardized anaesthetic protocol and selected from anaesthetic records of a period of three years, based on pre-defined inclusion criteria.MethodsIn group O (n = 100), medical oxygen acted as carrier gas, while in group M (n = 100), a medical mixture of oxygen and air (FIO2 0.60) was used. Demographic data, FIO2, arterial oxygen tension (PaO2) and routinely monitored physiologic data were recorded. The alveolar-arterial oxygen tension difference [P(A-a)O2] and PaO2/FIO2 ratio were calculated. The area under the curve, standardized to the anaesthetic duration, was calculated and statistically compared between groups using t-tests or Mann–Whitney tests as appropriate. Categorical data were compared using Chi-square tests.ResultsNo significant differences in age, body weight, sex, breed, surgical procedure, position, anaesthetic duration or arterial carbon dioxide tension were found. Mean FIO2 was 0.78 in group O and 0.60 in group M. Compared to group O, significantly lower values for PaO2 and for P(A-a)O2 were found in group M. In contrast, the PaO2/FIO2 ratio and the percentage of horses with a PaO2 <100 mmHg (13.33 kPa) were comparable in both groups.ConclusionsAlthough a reduction of the inspired oxygen fraction resulted in a lower PaO2, the P(A-a)O2 was also lower and the number of horses with PaO2 values <100 mmHg was comparable.Clinical relevanceIn healthy isoflurane anaesthetized horses, the use of a mixture of oxygen and air as carrier gas seems acceptable, but further, prospective studies are needed to confirm whether it results in a lower degree of ventilation/perfusion mismatching. 相似文献
75.
Athanasios Balidakis Theodora Matsi Anastasia-Garyfallia Karagianni Ioannis Ipsilantis 《Soil Use and Management》2023,39(4):1403-1421
Sewage sludge treated with 15% bentonite, vermiculite or biochar was evaluated as a soil amendment in comparison to limed and untreated sludge. Seven treatments were established to two soils, an acid and an alkaline, in three replications, i.e. 2% addition of sludge treated with bentonite, vermiculite, biochar and lime and application of 2% untreated sludge, inorganic fertilization and no sludge or inorganic fertilizers (control). Then, the soil treatments were used in a pot experiment with perennial ryegrass (Lolium perenne L.) as a test plant. Sludge treated with the clay minerals or biochar improved pH of the acid soil and significantly increased organic matter and available nutrients of both soils compared to control. Although no salinity or sodicity hazard was evidenced, the initial salinity of acid and alkaline soil increased by four-eight and two-three times, respectively, upon addition of all sludge treatments, especially that of untreated sludge. Moreover, soil available zinc (Zn) increased by four-eight times. Soil application of sludge treated with the clay minerals or biochar increased the total aboveground biomass yield of ryegrass in the acid and alkaline soil by 133%–171% and 72%–88%, respectively, compared to control and enhanced nutrient uptake by plants. Furthermore the microbial metabolic quotient indicated lack of low pH and heavy metal stress with addition of sludge to the acid soil. After three harvests of ryegrass, the residual effect of sludge on pH of acid soil and salinity, available phosphorus (P), Zn and boron (B) of both soils still persisted. Thus sewage sludge treated with 15% bentonite, vermiculite or biochar could be applied to soils at a rate of 2% (≈80 Mg ha−1) to serve as soil amendment and fertilizer for grasses and pasture species; however, caution is needed regarding possible P build-up, Zn phytotoxicity and salinization risks. 相似文献
76.
Sotiris Stasinos Marios Kostakis Nikolaos Thomaidis Ioannis Zabetakis 《Water, air, and soil pollution》2014,225(10):1-14
Tropospheric ozone (O3) has long been documented to cause an injury to plants, but a plants’ protectant, widely applicable in agronomical practice, does not exist. We evaluated the potential antiozonate efficacy of the antitranspirant di-1-p-menthene (Vapor Gard) compared with ethylenediurea (EDU) on Bel-W3 tobacco plants. Plants were treated either with water, or by EDU (10, 100, and 500 mg dm?3), or by vapor (1, 5, 10, and 50 ml dm?3) and were exposed either to O3-enriched (90 ppb) or O3-free air, for 12 days and 8 h day?1. EDU when applied at 10 mg dm?3 did not protect the plants against O3, but when applied at 100 and 500 mg dm?3 offered a significant protection to the plants. Vapor, when applied at 1 ml dm?3 did not protect the plants against O3, neither by terms of foliar visible injury nor by terms of aboveground biomass. In addition, when applied at 10 and 50 ml dm?3 caused phytotoxicity to all the plants, which it was expressed as necrotic spots on the leaves’ surface, misshaping of the leaves, or short plants' height. It is obvious that vapor does not protect Bel-W3 tobacco plants against O3. The antiozonate role of di-1-p-menthene is species-specific and probably occurs only under short-term exposures. 相似文献
77.
George Arampatzis Evangelos Hatzigiannakis Andreas Panagopoulos Aikaterini Karyoti Ioannis Vrouchakis Theodore Karyotis 《Journal of plant nutrition》2013,36(17):2232-2240
Water availability is an important factor for irrigated agriculture in the Mediterranean countries, because it affects significantly crop production. Surface soil samples were collected in Merambelo area located in Eastern Crete and analyzed. High values for exchangeable potassium and magnesium values were recorded and can be attributed to intensive fertilization and soil heredity factors. Groundwater quality based on two sampling campaigns performed during two irrigation periods. Three different scenarios were taken into account regarding the height of water application by means of irrigation. The contribution and the effects of nutrients and micronutrients from irrigation water to the soil was calculated, on the basis of the mean determined concentrations and the volume of applied irrigation. Significant variation was recorded in most soil properties, and these differences may be attributed to different mobility of nutrients, erosion factors, fertilization practices, and hydraulic soil properties. 相似文献
78.
Thomas E. Sotiropoulos Athanassios Molassiotis Dimitrios Almaliotis Gethsimani Mouhtaridou Kortessa Dimassi Ioannis Therios 《Journal of plant nutrition》2013,36(3):575-583
The in vitro response of the apple rootstock MM 111 to increasing concentrations of boron (B) (0.1, 0.5, 1, 3, and 6 mM) in MS medium is reported. The in vitro cultures of MM 111 shoots produced the highest fresh mass when 0.1 mM B was included in the medium. By increasing B concentration of the culture medium from 0.1 to 6 mM, B, phosphorus (P), calcium (Ca), and magnesium (Mg) concentrations of explants increased, whereas potassium (K), iron (Fe), manganese (Mn), and zinc (Zn) concentrations decreased. Chlorophyll content (SPAD units) of leaves declined as B concentration of the culture medium increased from 0.1 to 6 mM. The highest peroxidase (POD) activity in leaves was recorded in the presence of 6 mM B in the medium. By increasing B concentration of the medium from 0.1 to 3 mM, catalase (CAT) activity increased in leaves. Superoxide dismutase (SOD) activity in leaves and stems increased as B concentration of the medium increased. The non-enzymatic antioxidant power activity of leaves (FRAP values) increased gradually as B concentration of the medium increased. 相似文献
79.
Charisiadis P Tsiafoulis CG Exarchou V Tzakos AG Gerothanassis IP 《Journal of agricultural and food chemistry》2012,60(18):4508-4513
A rapid and direct low micromolar 1H NMR method for the simultaneous identification and quantification of hydrogen peroxide and phenolic compounds in plant extracts was developed. The method is based on the highly deshielded 1H NMR signal of H?O? at ~10.30 ppm in DMSO-d? and the combined use of picric acid and low temperature, near the freezing point of the solution, in order to achieve the minimum proton exchange rate. Line widths of H?O? below 3.8 Hz were obtained for several Greek oregano extracts which resulted in a detection limit of 0.7 μmol L?1. Application of an array of NMR experiments, including 2D 1H-13C HMBC, spiking of the samples with H?O?, and variable temperature experiments, resulted in the unequivocal assignment of H?O? precluding any confusion with interferences from intrinsic phenolics in the extract. 相似文献
80.
Arbuscular mycorrhizal (AM) fungi have a key role for plant nutrition in organic farming systems where crop protection relies on biopesticides. Although these are considered safe, their effects on non-target organisms, such as AM fungi, are not known and should be evaluated. A pot and a field experiment were employed to investigate the impact of biological pesticides (azadirachtin, spinosad, pyrethrum and terpens) on exogenous AM fungal inoculum (pots) and on indigenous AM fungi (field). The synthetic fungicide carbendazim and non-pesticide treated controls with or without mycorrhizal inoculation were also included. Plant growth and root colonization were measured 20 and 40 days post inoculation (dpi) in the pot experiment, or 40 and 90 dpi in the field study. Pesticide effects on the structure of the intraradical AM fungal community were determined via DGGE and cloning. Spinosad, pyrethrum and terpenes did not affect the colonization ability and the structure of the AM fungal community. On the contrary, pot application of azadirachtin resulted in a selective inhibition of the Glomus etunicatum strain of the inoculum. DGGE analysis showed that the field application of azadirachtin induced significant and persistent shifts in the AM fungal community. Carbendazim completely hampered mycorrhizal colonization in pots, compared to its field application which had a transitory effect on the colonization ability and the community structure of indigenous AM fungi. Our study provides first evidence for the effects of biological pesticides on the diversity of AM fungi. 相似文献