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Charles Rodde Hugues de Verdal Marc Vandeputte Franois Allal Julie Nati Mathieu Besson Felipe R Blasco John A H Benzie David J McKenzie 《Journal of animal science》2021,99(6)
Feed efficiency (FE) is the amount of body weight gain for a given feed intake. Improving FE through selective breeding is key for sustainable finfish aquaculture but its evaluation at individual level is technically challenging. We therefore investigated whether individual routine metabolic rate (RMR) was a predictor of individual FE in the European sea bass Dicentrarchus labrax, a major species in European mariculture. The European sea bass has three genetically distinct populations across its geographical range, namely Atlantic (AT), West Mediterranean (WM), and East Mediterranean (EM). We compared FE and RMR of fish from these three populations at 18 or 24 °C. We held 200 fish (62 AT, 66 WM, and 72 EM) in individual aquaria and fed them from ad libitum down to fasting. FI was assessed for an ad libitum feeding rate and for a fixed restricted ration (1% of metabolic body weight·day−1, with metabolic body weight = body weight0.8). After being refed 12 wk in a common tank, individual RMR was measured over 36 h by intermittent flow respirometry. There was a significant effect of temperature whereby fish at 18 °C had greater mean FE (P < 0.05) and lower RMR (P < 0.001). There was also a significant effect of population, where AT fish had lower FE (P < 0.05) and greater RMR (P < 0.001) than WM and EM, at both temperatures. Despite these differences in temperature and population means, individual FE and RMR were not significantly correlated (P > 0.05). Therefore, although the results provide evidence of an association between metabolic rate and FE, RMR was not a predictor of individual FE, for reasons that require further investigation. 相似文献
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Raffaele Spinelli Natascia Magagnotti Carla Nati 《European Journal of Forest Research》2011,130(5):737-744
In Italy, poplar plantations represent an important source of wood products, and especially of high-quality veneer logs. These
plantations offer favourable conditions to the introduction of forest mechanisation, and especially easy access and industrial
management. However, owners fear that mechanised log-making may cause value losses, due to poor length measurement, log surface
damage and improper grading. This study compared the performance of manual and mechanised log-making on ten commercial operations,
in order to determine the occurrence and the severity of possible value losses due to product degrade. The study found that
length measurement errors are smaller for mechanised processing, while the frequency and severity of log surface damage are
the same for both treatments. In three cases out of five, mechanised log-making extracted the same value from the stems as
manual log-making: in the remaining two, differences were very small and went opposite directions. Significant differences
were found between operators, stressing the importance of operator skills and motivation. In fact, the log-making specifications
and the pricing structure applied to poplar processing are relatively simple and are unlikely to challenge the ability of
personnel and equipment. At present, most Italian poplar growers are unaware of the potential offered by modern technology,
whose intelligent use would boost value recovery and decrease harvesting cost. Significant benefits may derive from the introduction
of optimised bucking, which may help shifting to a more articulated and rewarding product strategy. 相似文献
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Valère Cesse Mel Vincent Boubié Bado Saliou Ndiaye Koffi Djaman Delphine Aissata Bama Nati Baboucarr Manneh 《Communications in Soil Science and Plant Analysis》2019,50(11):1321-1329
Estimation of yield reduction in crop caused by the salinity stress is mostly based on variations of soil electrical conductivity and the severity of water stress. Crop response curves to salinity were developed without considering ion toxicity and nutritional imbalance in the plant. The objective of this study was to explore the possibility of using the ratio of the concentration of potassium by sodium in rice leaf (leaf-K/Na) to predict yield under the salinity stress. The rice (Oryza sativa L.) yield under fresh and saline condition and the leaf-K/Na related database was created. Data were collected from consecutive three seasons of a field experiment in the Africa Rice Center experimental farm in Senegal (16° 11? N, 16° 15?W). We studied the relationship between the relative yield (Yr), a ratio of yield under the salinity stress to the potential yield and the leaf-K/Na (x). Furthermore, we did regression analyses and F-test to determine the best fitting function. Results indicate that the exponential function [i.e. Yr = 100 exp (-b x)] was the best fitting model with the lowest root mean square error (9.683) and the highest R2 value (0.90). Example applications on independent data from published papers showed relatively good predictions, suggesting that the model can be used to predict rice yield in saline soils. 相似文献
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Yuval Ramot Michal Steiner Yossi Lavie Nati Ezov Orgad Laub Eran Cohen Yotam Schwartz Abraham Nyska 《Journal of toxicologic pathology》2021,34(4):319
Bleeding during surgical procedures is a common complication. Therefore, hemostatic agents have been developed to control bleeding, and fibrin sealants have several benefits. sFilm-FS is a novel fibrin sealant that comprises a biodegradable co-polymeric film embedded with human fibrinogen and thrombin. Herein, the safety and efficacy of sFilm-FS were compared using a liver and spleen puncture model of Göttingen minipigs with those of the standard hemostatic techniques (control animals) and EVARREST®, a reference fibrin sealant. Hemostasis and reduced blood loss were more effectively achieved with sFilm-FS than with the standard techniques in the control animals and comparable to those achieved with EVARREST®. No treatment-related adverse effects were observed in any of the groups. Histopathological evaluation indicated that sFilm-FS was slightly and moderately reactive at the liver puncture site and spleen, respectively, compared with the standard techniques in the control animals. These changes are expected degradation reactions of the co-polymeric film and are not considered as adverse events. No treatment-related abnormalities were noted in the other evaluated organs. Additionally, no evidence of local or systemic thromboses was noted. These results support the use of sFilm-FS for hemostasis in humans. 相似文献
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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
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Valère Cesse Mel Vincent Boubié Bado Saliou Ndiaye Koffi Djaman Delphine Aissata Bama Nati Baboucarr Manneh 《Archives of Agronomy and Soil Science》2019,65(8):1093-1106
Growing rice in saline soils by minimizing damage on growth and yield remains a challenge. We conducted field experiments in the Africa Rice research field located in the Senegal River delta (16° 11? N, 16° 15? W) to study the effects of three management options of fertilization e.g. (i) nitrogen, phosphorus, and potassium fertilization: NPK; (ii) NPK combined with zinc: NPK-Zn, and (iii) NPK combined with gypsum: NPK-gypsum on the soil salinity level, the nutrient uptake and the productivity of different rice cultivars. The whole objective of this study is to determine how zinc or gypsum associated to NPK fertilizer can improve the growth and productivity of rice crop in saline soil. Results showed that the initial soil salinity level was reduced rapidly in plots treated with gypsum. The leaf-K/Na ratio, agronomic nitrogen use efficiency (ANUE), and grain yield of rice cultivars under the salinity stress were improved by the NPK-gypsum and NPK-Zn options relatively to the NPK option, suggesting that NPK-gypsum and NPK-Zn are suitable management options in reducing adverse effect of low K/Na, low ANUE as well as to improve rice yield under salinity stress. 相似文献
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Sweet chestnut has been for many centuries essential to human diet in large areas of Southern Europe. Its cultivation was abandoned in the last century, but is at present under restoration for socioeconomic reasons, representing also an opportunity for allocating woody residues to the energy sector. A little is known from the literature about sweet chestnut pruning, and the aim of the study was to assess the biomass yield and quality, the productivity and costs of the system as well as its energetic balance between inputs and outputs. The yield of recovered wood material amounted to between 22.3 tonnes of dry matter per hectare (tdw ha?1) and 33.3 tdw ha?1. Time consumption for pruning has been related to trees’ DBH, so detecting a linear relationship, although weak, between tree size and the time spent for maintenance. Productivity expressed as tdw per hour varied according to the site and the operating systems adopted accordingly. Costs for the whole chain, excluding transport to the plant facility amounted to 113 or to 430 € t dw ?1 depending on the terrain relief and the presence of an underbrush to be cleaned. Wood chips distribution in size classes provided a material unsuitable for non-industrial due to the percentage of oversize particles, probably due to the high presence of twigs. The energy ratio resulted of 30:1 and 21:1 for the two sites. Transportation had the main impact in terms of energy, followed by extraction and chipping phases. 相似文献