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11.
Stefania Uccheddu Eliana Pintus Jose Julian Garde Lidia Fleba Marco Muzzeddu Flavia Pudda Luisella Bogliolo Alessandro Strina Stefano Nieddu Sergio Ledda 《Reproduction in domestic animals》2020,55(10):1294-1302
Habitat degradation leads to small and fragmented populations, lower genetic variability and fertility overtime. Assisted reproductive techniques represent important tools to cope with the dramatic loss of biodiversity. Fallow deer (Dama dama), beyond its high commercial value and wide distribution, may represent the most suitable model to study endangered cervids. In this study, oocytes were recovered post-mortem from fallow deer during the breeding and no breeding seasons and were in vitro matured (IVM). The ability of cryopreserved thawed sperm samples recovered by electroejaculation from four adult males was tested by in vitro fertilization of IVM oocytes. The number of oocytes collected per ovary did significantly vary across seasons from 6.2 ± 0.92 during breeding season to 10.4 ± 1.26 during no breeding season (p = .006). Oocytes collected during the breeding season showed higher in vitro fertilization rate compared to the no breeding season (p = .045). However, no embryos reached the blastocyst stage. Semen samples obtained by electroejaculation were successfully cryopreserved, although the cryopreservation process negatively affected most kinetic parameters, mainly at 2 hr post-thawing. Moreover, the percentage of rapid spermatozoa significantly decreased between fresh samples and at 2 hr post-thawing, whereas the percentage of slow spermatozoa increased across the same period (p < .05). Our study provides the logistic steps for the application of assisted reproductive techniques in fallow deer and might be of great interest for genetic resource bank planning. 相似文献
12.
Loretta Triberti Anna Nastri Gianni Giordani Franca Comellini Guido Baldoni Giovanni Toderi 《European Journal of Agronomy》2008,29(1):13-20
The soil organic matter content represents a huge reservoir of plant nutrients and an effective safeguard against pollution; beside it can sequestrate atmospheric CO2. Since 1966 up to now in the Southeast Po valley (Italy), the soil organic C (SOC) and total N (TN) dynamics in the 0–0.40 m soil layer under a maize–wheat rainfed rotation are studied as influenced by organic and mineral N fertilizations. Every year in the same plots cattle manure, cattle slurry, and crop residues (i.e. wheat straw and maize stalk) are ploughed under to 0.40 m depth at a same dry matter rate (6.0 and 7.5 t DM ha−1 year−1 after wheat and maize, respectively) and are compared to an unamended control. Each plot is splitted to receive four rates of mineral fertilizer (0–100–200–300 kg N ha−1). In the whole experiment, in 2000 SOC concentration was lower than in 1966 (6.77 and 7.72 g kg−1, respectively), likely for the deeper tillage that diluted SOC and favoured mineralization in deeper soil layer. From 1972 to 2000 SOC stock did not change in the control and N fertilized plots, while it increased at mean rates of 0.16, 0.18, and 0.26 t ha−1 year−1 with the incorporation of residues, slurry and manure, corresponding to sequestration efficiencies of 3.7, 3.8 and 8.1% of added C with the various materials. TN followed the same SOC dynamic, demonstrating how it depends on the soil organic matter. Manure thus confirmed its efficacy in increasing both SOC content and soil fertility on the long-term. In developed countries, however, this material has become scarcely available; slurry management is expensive and implies high environmental risks. Moreover, in a C balance at a farm (or regional) scale, the CO2 lost during manure and slurry stocking should be considered. For these reasons, the incorporation of cereal residues, even if only a little of their C content was found capable of soil accumulation, appears the best way to obtain a significant CO2 sequestration in developed countries. Our long-term experiment clearly shows how difficult it is to modify SOC content. Moreover, because climate and soil type can greatly influence SOC dynamic, to increase CO2 sequestration in cropland, it is important to optimize the fertilization within an agricultural management that includes all the agronomic practices (e.g. tillage, water management, cover crops, etc.) favouring the organic matter build up in the soil. 相似文献
13.
Chemical and biological diversity of Bergamot (Citrus bergamia) in relation to environmental factors
Oil of bergamot is receiving renewed popularity in aromatherapy. The biovariability of Citrus bergamia grown wild in Calabria (Italy) was investigated as far as chemical markers (linalool, linalyl acetate and bergapten) content and antioxidant and antifungal activities of the methanolic extracts. The average content in the markers presents slight variations with the altitude and more evident changes with the latitude of the areas of plant collection. 相似文献
14.
Variability in the content of active constituents and biological activity of Glycyrrhiza glabra 总被引:1,自引:0,他引:1
Nine samples of Glycyrrhiza glabra were collected in various sites of Calabria, Italy, with the aim to determine the variability in the confront of active constituents and in antibacterial and antifungal activities of the extracts. The samples showed remarkable differences in chemical composition and biological activity. 相似文献
15.
Dall'Asta C Falavigna C Galaverna G Dossena A Marchelli R 《Journal of agricultural and food chemistry》2010,58(22):12042-12047
Hidden fumonisins have received great attention in the last years as they have been frequently found in maize products in addition to the free forms. Several papers have shown that interaction with macromolecular components such as protein and starch is at the base of the phenomenon: although the nature of the interaction (covalent or not) is still not clarified, the occurrence of hidden forms is generally revealed by the application of an alkaline hydrolysis procedure. In this study, an in vitro digestion model has been applied to raw maize to evaluate the possible release of hidden fumonisins under gastrointestinal conditions. Upon digestion of the food matrix, an increased amount of total detectable fumonisins was observed in comparison with the analysis on the nondigested matrix, an amount even higher than that calculated through the application of the hydrolysis procedure. Besides the analytical issues, our data have serious implications, since consumers may be exposed to a systematic higher risk than that estimated by conventional techniques. 相似文献
16.
Six aphid species new for Italy were caught by suction trap in the Friuli-Venezia Giulia region, Italy. They are:Chaetosiphon chaetosiphon (Nevsky),Illinoia morrisoni (Swain),Myzodium modestum (Hottes),Pseudacaudella rubida (Börner),Schizaphis longicaudata Hille Ris Lambers andTrichosiphonaphis (Xenomyzus)polygonifoliae (Shinji). All species are provided here with characteristic morphological information and line drawings. 相似文献
17.
Valeria Pasciu Maria Nieddu Elena Baralla Cristian Porcu Francesca Sotgiu Fiammetta Berlinguer 《Journal of veterinary diagnostic investigation》2022,34(1):90
Determination of serum or plasma progesterone (P4) concentrations is important to recognize pregnant and non-pregnant ewes, and also to predict the number of carried lambs. The 2 most common methodologies for the detection of plasma P4 are radioimmunoassay (RIA) and enzyme immunoassay (EIA). RIA is very expensive, and not all laboratories are equipped to perform this test; EIA is commercially available for human use, but only a few companies produce species-specific kits, which are expensive. We verified for ovine plasma a less expensive and easily available ELISA kit (DiaMetra) designed to quantify P4 in humans. Pools of ovine and human plasma were used to compare repeatability, accuracy, sensitivity, and stability of P4 measured by the DiaMetra kit. Repeatability data were within 15%, and accuracy values were ~90% for both plasma matrices. Stability data showed a loss of <20% for freeze–thaw and <30% for 30-d storage. All parameters were acceptable under international guidelines for method validation. The human ELISA kit was used successfully to quantify plasma P4 in 26 ewes during pregnancy until delivery. P4 concentrations were also correlated with the number of carried lambs. 相似文献
18.
Gianni Brundu Barbara Loi Anuta Chindris Philip Graham Dimitri Bernab Gemma Gimnez Papiol 《Aquaculture Research》2020,51(7):2936-2947
Shell characteristics and consequent marketability of the oyster Crassostrea gigas are influenced by several factors, and most important of which are the rearing methods and gears. In this study, we investigated the effects of two different gears on the quality aspect (shell shape, weight meat percentage, backward shell shape, epibionts and blisters) and growth rate (weight and length) of C. gigas by adopting the innovative Ortac Oyster Farming System, during the field grow‐out phase of production. Aspect and growth of oysters farmed in Ortac and floating bags were compared. After 14 weeks, the aspect of the animals was influenced by the gear, resulting in a lower quality in the Ortac (i.e. worse shell shape, lower weight meat percentage, higher percentage of backwards and blisters) than in the floating bag, while the incidence of epibionts was less in the Ortac. Regarding the growth performance, total wet weight gained in the Ortac was lower (~28.3 g) than in the floating bag (~32.4 g; p < .05). These results highlight the efficiency of the floating bag as oyster rearing system in the Mediterranean basin and suggest the need to alter the Ortac gear to these environmental conditions. 相似文献
19.
Utilizing the weather generator ClimGen, daily solar radiation (Rs) and vapor pressure deficit (VPD) were estimated from temperature data and used to calculate evapotranspiration at five locations, representing tropical, temperate, semi-arid, and arid climates. ClimGen was calibrated for each location using the most recent 2 or 5 years of complete daily weather records. Actual and estimated values were compared on a daily and weekly (7-day running average) basis. Error indices were defined to indicate excellent to poor performance of the estimation methods. Overall in all locations, the ClimGen estimates for both daily Rs and VPD were poor to acceptable. The weekly analyses showed significant improvement in performance for both Rs and VPD estimations in arid and semi-arid locations. Daily reference crop evapotranspiration values using the FAO Penman-Monteith equation (PM ETo) were calculated using complete daily weather records. These values were compared with (1) ETo calculated with the PM model, actual temperature data, and ClimGen estimates of daily Rs, VPD, and generated wind speed (PMEst ETo), and (2) ETo calculated solely from actual daily temperature data using a calibrated version of the Hargreaves method (HGAdj ETo). The daily PMEst ETo results were poor to acceptable in all locations, but analyses for weekly periods showed improved performance to acceptable and good levels for arid and semi-arid locations. The performance of the HGAdj ETo method was also poor to acceptable for daily ET estimates in all locations, while weekly analyses showed improvement. A non-calibrated version of the Hargreaves method did not work for either daily or weekly periods. The PMEst ETo and HGadj ETo methods appeared suitable for weekly periods in arid and semi-arid locations provided that at least 2 years of complete weather records were available to calibrate the parameters required. There was no advantage in using 5 years of weather records for calibration.Communicated by E. Fereres 相似文献
20.
Natascia Magagnotti Carla Nati Gianni Picchi Raffaele Spinelli 《Agroforestry Systems》2011,82(1):77-86
The study compares two product strategies—chips versus firewood—and two technological levels—manual versus mechanized—as applied
to the thinning of walnut agroforestry plantations, established on ex-arable land. Such plantations are widespread all across
Europe, and their establishment was subsidized under the provisions of EU Directive 2080/90, and of regional grant schemes.
Field test data were used to build a simple deterministic model for estimating thinning productivity and cost under varying
work and economic conditions. This model can assist prospective users when checking the profitability of an operation, or
when assessing the competitiveness of alternative options. Removing nurse alder from young walnut plantations yields between
25 and 50 t of fresh biomass per hectare and is crucial to the good development of the stand. The study shows that the removal
of nurse alder from walnut plantations is economically viable, and it can also offer some profits if stand and market conditions
are favourable. As a rule, the average DBH of removal trees should not be smaller than 12 cm. Best results are obtained with
mechanized harvesting, which does not seem to cause heavier stand and soil damage than manual harvesting. Manual harvesting
is preferable only if the annual utilization of machinery is very low, and in this case it should be geared to firewood production.
The manual whole-tree harvesting (WTH) method used in this study offers the lowest performance under all conditions, and should
be replaced with some other manual alternative to WTH. Mechanized WTH offers a significant cost reduction over mechanized
short-wood (SWS) harvesting, but this difference is still rather limited: hence, other parameters come into play when deciding
what system to apply, and namely product price and mass output. In this respect, one also has to consider the cost of managing
the harvesting residue, and that of fertilizing, if soil nutrient depletion is to be feared. 相似文献