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排序方式: 共有561条查询结果,搜索用时 31 毫秒
131.
Miguel Urrestarazu Victor Gallegos Juan Eugenio Álvaro 《Communications in Soil Science and Plant Analysis》2017,48(13):1595-1602
Thermography is a tool used in many scientific disciplines, including agriculture. Determining the behavior of a nutritive solution in soilless culture containers using substrates is very important in order to establish the position of drippers, drainage holes, the use of humidification agents, and fertigation management in culture units. This paper describes the application of thermography to determine the humidification bulb in horticulture crops to rapidly diagnose the best way to advance fertigation in different horticultural substrates in soilless culture. Thermography was seen to be an excellent tool for evaluating the movement and distribution of the nutritive solution within the soilless culture container with different substrates. 相似文献
132.
Drago SR Velasco-González OH Torres RL González RJ Valencia ME 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(2):43-48
The effects of extrusion conditions on cooking degree, flour dispersion viscosity and mineral potential availability of extruded
bean flour were studied. Phaseolus vulgaris beans of the agronomic cultivar “Flor de mayo” were ground and dehulled to obtain
grits and then extruded at different temperatures (140, 160 and 180 °C) and moisture contents (17, 20 and 23%), according
to a bifactorial experimental design. Degree of cooking was estimated by water solubility (WS) and specific mechanical energy
(SME). The effect of variables on WS and SME were analysed by surface response methodology. Flour dispersion viscosity and
mineral availability (estimated by in vitro dialyzability), were also evaluated on selected samples. Results showed that, within the ranges of the variables used for
this study, only the effect of temperature was significant on the degree of cooking. No direct correlation was observed between
water solubility and SME, although a maximum value of WS corresponded to a range of SME values of 400–500 J/g was observed.
Dispersion viscosity decreases as WS increases, so if high calorie density is desired, for instance in order to produce a
cream soup formula, bean grits should be extruded at high temperature and as low moisture as possible, in our case 180 °C
and 17% moisture. On the other hand, the effects of extrusion variables on iron and zinc dialyzability were not much affected. 相似文献
133.
A. Luzardo-lvarez J. Martínez-Mazagatos M. T. Santamarina-Fernndez F. J. Otero-Espinar J. Blanco-Mndez 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):15-25
The aim of this work was to explore the efficacy of a veterinary drug, Triclabendazole (5-chloro-6-(2, 3-dichlorophenoxy)-2-methylthio-1H-benzimidazole), in an inclusion complex with β-cyclodextrin as a suitable treatment for parasitic diseases caused by Ichthyophthirius multifiliis in rainbow trout. The efficacy was determined by the reduction in the infection intensity. The complexes were prepared by the kneading method and were characterized by DSC and X-ray diffractometry. The selected stoichoimetry was 1:3 because of the higher percentage of Triclabendazole complexed with cyclodextrin. Administration of Triclabendazole and complex was carried out by including appropriate doses in animal feed. Our studies suggest that the Triclabendazole–cyclodextrin complex results in a reduction in the infection degree and trophont size is decreased in the animals treated. The oral treatment of Triclabendazole in inclusion complexes may be an alternative to bath treatments in trout farming. 相似文献
134.
Julia Pinedo-Gil Ana Tomás-Vidal Daniel Rico Brijesh Tiwari Carlos Álvarez García Miguel Jover-Cerdá 《Journal Of Aquatic Food Product Technology》2019,28(5):495-504
Barley concentrations ranging from 0% to 32% were incorporated into rainbow trout (Oncorhynchus mykiss) diets. The effect of barley concentration on lipid peroxidation and antioxidant activity of fish fillets were analyzed. Results showed that the inclusion of barley in rainbow trout diets had an inhibitory effect on lipid oxidation, probably associated with certain bioactive compounds in barley that could interact with scavenging and reducing metabolites involved in lipid oxidation. Concentrations up to 8% of barley produced fish fillets with high antioxidant activity and higher levels of alpha-tocopherol. 相似文献
135.
A molecular tool for parentage analysis in the Mediterranean mussel (Mytilus galloprovincialis)
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Ania Pino‐Querido José M Álvarez‐Castro Manuel Vera Belén G Pardo José Fuentes Paulino Martínez 《Aquaculture Research》2015,46(7):1721-1735
Estimation of selection response and genealogical tracing in family mixtures require an appropriate tool for parentage analysis. In this study, we tested 19 marker loci for parentage analysis allocation in Mediterranean mussel (Mytilus galloprovincialis). To this aim, we reared families in tanks isolated from wild mussel seed, analysed them using the 19 marker loci and characterized their performances based on Mendelian rules. Probabilities of exclusion of a false parent were estimated for different groups of loci and contrasted to the real paternity assignment. Based on this, we chose nine microsatellites with the highest exclusion probabilities and a real paternity assignment of 99.6%. Next, we analysed 600 individuals reared as in the usual production process, where contamination from wild seed is likely. We obtained a real assignment of 94.7% and were able to identify individuals from the wild as the most likely hypothesis to explain the observed incompatibilities with candidate parents. This information was used to evaluate parental contribution in offspring obtained from gamete mixtures of several parents, which bestowed results of interest for future breeding programs of Mediterranean mussel. 相似文献
136.
Yolanda Torres‐Corral Clara Fernndez‐lvarez Ysabel Santos 《Journal of fish diseases》2019,42(10):1359-1368
This work describes a primer pair and a high‐throughput SYBR Green I‐based real‐time PCR protocol combined with melting curve analysis for identification and quantification of Vagococcus salmoninarum in bacterial cultures and infected fish tissues. The 16S rRNA gene was selected for the design of the primer pair (SalF and SalR). The sensitivity and specificity of this primer pair were compared with other previously designed for conventional PCR. Although both primer pairs showed 100% specificity using pure bacterial cultures or DNA extracted from bacteria or fish tissues, the primer pairs designed in this study showed the highest sensitivity with a detection limit of 0.034 × 100 amplicon copies per assay (equivalent to 2 × 10?11 ng/µl, Cq value of 30.49 ± 1.71). The developed qPCR protocol allowed the detection of V. salmoninarum in non‐lethal and lethal fish samples with detection levels of 0.17 × 100 gene copies in tissues artificially infected and 0.02 × 100 in tissues of fish experimentally infected with V. salmoninarum. The high sensitivity of the developed method suggests that it could be considered as a useful tool for diagnosis of vagococcosis and the detection of V. salmoninarum in asymptomatic or carrier fish. 相似文献
137.
Miguel Urrestarazu Lizette Borges Silvia Burés Juan Eugenio Álvaro 《Journal of plant nutrition》2013,36(4):562-565
□ Plants from 60-day-old Lime Thyme (Thymus citriodorus) cuttings were potted in a medium of coconut fiber and peat moss and were treated with three different nutrient solutions: T1, T2, and T3. T1 was a standard nutrient solution; T2 was incremented with macronutrients up to an electrical conductivity (EC) of 2.8 dS m?1; and T3 was the same as T1 but incremented up to an EC of 2.8 dS m?1 with sodium chloride. The plants were then grown for 90 days in a greenhouse with natural daylight in Almería, Spain. Root growth was not affected by the treatments. The dry weight of the leaves and the total dry weight of the plants benefited from the salinity. The specific salinity of the sodium chloride negatively affected growth compared to the same salinity in the complete nutrient solution. 相似文献
138.
Genetic diversity loss due to selection for scrapie resistance in the rare Spanish Xalda sheep breed
I. lvarez L.J. Royo J.P. Gutirrez I. Fernndez J.J. Arranz F. Goyache 《Livestock Science》2007,111(3):204-212
The effect of selection for scrapie resistance on genetic variability in the rare Xalda sheep breed was studied. Pedigree information comprised 1851 animals (1444 alive) at the moment of sampling. A total of 304 reproductive (or selected for reproduction) Xalda individuals were sampled and genotyped for 14 microsatellites. Genetic variability was assessed using: gene diversity (1 − average kinship, GD), mean average relatedness (AR) and self-coancestry (ci) at the genealogical level; and expected heterozygosity (He), molecular mean kinship (Mk), molecular self-coancestry (si) and rarefacted average number of alleles per locus (A) at the molecular level. Two breeding strategies were evaluated: a) use of only young rams with genotype ARR/ARR and young ewes with low to moderate risk (risk groups R1 to R3); b) breeding without selection for PrP genotypes. The major cause of losses of genetic variability in the Xalda breed is the drift that occurs when a new group of reproductive individuals is selected. The loss of genetic variability is small in females compared to the males, where it is considerable. However, losses at the molecular level for young females with respect to adult females were above 5%. Young male individuals also retained most of the genetic variability assessed in adult rams. Selection against susceptibility to scrapie produced additional losses of more than 2% for He and A when rYF individuals are considered. As regards males, the situation becomes critical because of the scant number of available ARR/ARR young rams. The consequences for the management of the Xalda breed are discussed. 相似文献
139.
Studbook performance records for 2734 Swedish standardbred trotter broodmares have been analysed. Transformation of most variables was necessary in order to approach normality of the records. The heritability for the traits varied between 0.10 and 0.68, the lowest value for transformed “number of starts” and highest for transformed “earnings per start”. Genetic correlations were very high or high between all traits except for transformed “number of starts”. Transformed “earnings” was found to be genetically almost identical with transformed “best life-time racing time”, but more suitable for selection purposes. Several selection indices were constructed and their use in mass-selection and for adjusting for non-random distribution of dam genotypes when progeny-testing stallions is discussed. 相似文献
140.
M. PILAR OLIVAR MIKHAIL EMELIANOV FERNANDO VILLATE IBON URIARTE FRANCESC MAYNOU IGNACIO ÁLVAREZ ELVIRA MOROTE 《Fisheries Oceanography》2010,19(3):209-229
In the northwestern Mediterranean, most fish species reproduce in early summer and fewer in the autumn mixing period. This study analyses and compares larval fish assemblages (LFA) in both seasons, and is the first attempt to characterize LFA structure for the autumn period. We analyze horizontal and vertical distribution of fish larvae and the micro- and mesozooplankton biomass and abundance of the main zooplankton groups. The oceanographic situation was analyzed through the study of data from CTD, Nν-Shuttle and ADCP surveys. LFA were determined by ordination analyses based on larval abundance, and the relationships between larval assemblages and environmental variables were investigated through canonical correspondence analysis. The importance of some hydrographic variables (temperature, salinity and stability of the water column), current fields (along-shelf and across-shelf transport) and the abundance of zooplankton are discussed as important factors shaping the structure of larval assemblages. In early summer, LFA were mainly structured by a combination of bathymetry and trophic components, although sea surface temperature also played a role in shaping the horizontal larval distributions. In autumn, trophic variables were the main factors influencing the shelf-dwelling species assemblage. Larvae of oceanic species, on the other hand, were not related to trophic variables but were more affected by current fields. 相似文献