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781.
Palmeri G Turchini GM Keast R Marriott PJ Morrison P De Silva SS 《Journal of agricultural and food chemistry》2008,56(19):9037-9045
The aim of this study was to determine the effects of starvation and water quality during the purging process on the biometric parameters, fatty acids, and flavor volatiles of Murray cod farmed in a recirculation system. Market size Murray cod, at the end of the grow-out stage, were divided into eight treatments. The treatments were either fed/starved (F or S) and kept in clean water (CW: CWF2, CWS2, CWF4, and CWS4) or fed/starved and kept in recycled water (RW: RWF2, RWS2, RWF4, and RWS4) for either 2 or 4 weeks. Fish were sampled at 0, 2, and 4 week intervals. Food deprivation was responsible for a significant (P < 0.05) weight loss compared to that of fed treatments. The same was observed for the condition factor (K), hepatosomatic index (HSI), and dress-out percentage (DP). No significant changes were, however, observed in the visceral fat index (VFI). Saturated fatty acids (SFA) were highest in RWF4 and lowest in CWS4 (P < 0.05), while monounsaturated fatty acids (MUFA) were lowest in CWF4 (P < 0.05). Starvation did not affect the flavor volatile compounds, which were mainly affected by changes in water quality. Specifically, total aldehyde (% w/w) content was significantly (P < 0.05) affected by water quality, but the time of purging was not responsible for any noteworthy differences. This study was able to separate the effects of starvation and water quality, in the purging process, on the final eating quality of farmed market size Murray cod. It is concluded that because of the inevitable weight loss during starvation, Murray cod should be fed during the purging stage but kept in clean water and deprived of food only for the time necessary to empty the gastro-intestinal tract. 相似文献
782.
783.
A novel type of seaweed extract as a natural alternative to the use of iron chelates in strawberry production 总被引:1,自引:0,他引:1
Francesco Spinelli Giovanni FioriMassimo Noferini Mattia SprocattiGuglielmo Costa 《Scientia Horticulturae》2010
The new generation of seaweed extracts, such as Actiwave®, may represent a promising strategy to reduce the use of phytochemicals in agriculture. Actiwave® is a metabolic enhancer derived by the algae Ascophillum nodosum, but differently from some older seaweed extracts, it has a constant and balanced formulation containing kahydrin, alginic acid and betaines which synergistically contribute to the efficacy of the product. Actiwave® has been proposed to increase the mineral nutrient uptake and the abiotic stress tolerance. The aim of this work was to evaluate, under a multidisciplinary approach, the effect of the biostimulant on the vegetative and productive performances of strawberry plants grown on a lime inducing iron chlorosis substrate. This biostimulant increased the vegetative growth (10%), the leaf chlorophyll content (11%), the stomata density (6.5%), the photosynthetic rate and the fruit production (27%) and berry weight. The most significant result was the increase of the plant biomass: the shoot dry matter was increased up to 27% and root dry matter up to 76%. Finally, preliminary experiments showed that Actiwave® positively influenced also the root-associated microbial biocoenosis. These results are discussed in relation to the physiological and ecological mechanisms proposed to explain the beneficial effects of this seaweed extract. Finally, the effects of Actiwave® and sequestrene were significantly similar, thus showing that this biostimulant may represent an environmental-friendly substitute of the iron chelates. 相似文献
784.
Giovanna Cucci Giovanni Lacolla Gianraffaele Caranfa 《Archives of Agronomy and Soil Science》2018,64(1):13-24
The aim of this research was to investigate the spatial distribution of roots and cracks in two clay soils cropped with sunflower under different inter-row spacing in order to identify the optimal management. A latin square experimental design was applied to compare bare soil and soil cropped with sunflower, with three plant densities, obtained by keeping constant the number of plants on the row (3 plants m?1) and varying the row spacing (0.4, 0.6, 0.8 m). The presence of the crop and the different distance between rows influenced soil moisture content as well as the root spatial distribution and thus the structural features of cracks. Increasingly lower values of moisture were found in both soils as the distance between rows decreased; an opposite trend was observed for both root density and crack size. The volume of cracks in the soil grown with sunflower at 0.4 m row spacing was 201.4 m3 ha?1, thus 8 times higher than the value on the bare soil and 2.5 times higher compared to the one grown at 0.8 m between rows. Optimal results in terms of root density, soil moisture and crack size were obtained with an inter-row spacing of 0.6 m. 相似文献
785.
Francesca Cecchi Claudia Russo Daniela Iamartino Alessia Galiero Barbara Turchi Filippo Fratini Sara Degl’Innocenti Raffaele Mazza Stefano Biffani Giovanna Preziuso Carlo Cantile 《Tropical animal health and production》2017,49(6):1135-1142
Paratuberculosis disease is a chronic bacterial disease infection of ruminants of global relevance, caused by MAP (Mycobacterium avium subsp. paratuberculosis). The present study was conducted on the Garfagnina goat breed that is an Italian native goat population registered on the Tuscan regional repertory of genetic resources at risk of extinction. Forty-eight adult goats (27 serologically positive to MAP-positive and 21 serologically negative to MAP-negative) belonging to a single flock that had experienced annual mortalities due to MAP infection were identified and genotyped with the Illumina GoatSNP60 BeadChip. Diagnosis was achieved by serological tests, as well as post-mortem examination of affected animals. A genome-wide scan was then performed on the individual marker genotypes, in an attempt to identify genomic regions associated with MAP infection disease. Nine significant markers were highlighted and they were located within, or nearby, annotated genes. Two genes found in this study encode are linked to protein kinases that are among the most important enzymes involved in the immune response to Johne’s disease, and four genes are involved in the functions of the Golgi complex. 相似文献
786.
Rhyzopertha dominica (F., 1792) (Coleoptera: Bostrichidae): a stored grain pest on olive trees in Sicily 下载免费PDF全文
E. Buonocore D. Lo Monaco A. Russo H. P. Aberlenc G. Tropea Garzia 《EPPO Bulletin》2017,47(2):263-268
In October 2014 samples were collected from olive trees growing in South‐Eastern Sicily (Italy) that were showing wilting symptoms. In the field, clear signs of flagging appeared on young twigs and lateral shoots, and many leaves had fallen to the ground. Initial laboratory examinations of attacked twigs revealed the presence of a large number of adults of Rhyzopertha dominica (F., 1792). Sampling was repeated during the following 2 years, and while an outbreak of the pest did not occur, continuous damage was observed. In 2016, exclusively using pheromone‐baited traps in olive trees, a large number of adults were captured. The main local climatic parameters were monitored from 2014 to 2016 and compared with the population levels. The incidence of damage and survival of R. dominica in an environment different from its usual one (stored grain) deserves attention, especially considering that climate change could greatly affect pest demographics and put olive trees in this area and further afield at risk of increased damage. 相似文献
787.
Aurelia Tubaro Anna Giangaspero Silvio Sosa Roberto Negri Gianpaolo Grassi Salvatore Casano Roberto Della Loggia Giovanni Appendino 《Fitoterapia》2010
A selection of seven phytocannabinoids representative of the major structural types of classic cannabinoids and their corresponding cannabivarins was investigated for in vivo topical anti-inflammatory activity in the Croton oil mouse ear dermatitis assay. Differences in the terpenoid moiety were far more important for anti-inflammatory activity than those at the C-3 alkyl residue, suggesting the involvement not only of cannabinoid receptors, but also of other inflammatory end-points targeted by phytocannabinoids. 相似文献
788.
Sylvie Oddou-Muratorio Aurore Bontemps Etienne K. Klein Igor Chybicki Giovanni G. Vendramin Yoshihisa Suyama 《Forest Ecology and Management》2010
The comparison between estimates of historical gene flow, using variance in allelic frequencies, and estimates of contemporary gene flow, using parentage assignment, is expected to provide insights into ecological and evolutionary processes at work within and among populations. Genetic variation at microsatellite loci was used to quantify genetic structure in two wind pollinated, gravity and animal-dispersed tree species (Fagus sylvatica L. and Fagus crenata Blum.) and to derive historical estimates of gene flow. The gene dispersal distances estimated assuming effective population density to be 1/4 of the observed density were ∼77 m in European beech and ∼40 m in Japanese beech. Parentage analyses and a neighbourhood model approach were used to estimate contemporary patterns of seed and pollen dispersal. Our results suggest restricted seed dispersal abilities in both European beech (δs = 10.5 m) and Japanese beech (δs = 12.4 m), with an exponential shaped seed dispersal kernel. A non-negligible rate of seed immigration (ms = 27%) was detected in European beech sites but not in Japanese beech site. Pollen dispersal within studied sites also appeared limited (δp = 41.63 m in European beech and δp = 79.4 m in Japanese beech), despite high rate of pollen immigration (mp = 68% in European beech and mp = 40% m in Japanese beech). Interestingly, contemporary and historical estimates of gene flow were within the same order of magnitude (a few tens of meters). 相似文献
789.
Michela Rigoni Anna Toffan Elisabetta Viale Marzia Mancin Filippo Cilloni Elena Bertoli Angela Salomoni Sabrina Marciano Adelaide Milani Bianca Zecchin Ilaria Capua Giovanni Cattoli 《Veterinary research》2010,41(5)
Highly pathogenic avian influenza (HPAI) viruses of the H5 and H7 subtype pose a major public health threat due to their capacity to cross the species barrier and infect mammals, for example dogs, cats and humans. In the present study we tested the capacity of selected H7 and H5 HPAI viruses to infect and to be transmitted from infected BALB/c mice to contact sentinels. Previous experiments have shown that viruses belonging to both H5 and H7 subtypes replicate in the respiratory tract and central nervous system of experimentally infected mice. In this study we show that selected H7N1 and H5N1 HPAI viruses can be transmitted from mouse-to-mouse by direct contact, and that in experimentally infected animals they exhibit a different pattern of replication and transmission. Our results can be considered as a starting point for transmission experiments involving other influenza A viruses with α 2-3 receptor affinity in order to better understand the viral factors influencing transmissibility of these viruses in selected mammalian species. 相似文献
790.
Aspergillus ochraceus, a widely distributed filamentous fungus, was isolated and identified by cytology and culture as the cause of unilateral ceruminous purulent otitis in a 4‐year‐old male mixed‐breed dog. The pathogenic role of the fungal isolate was confirmed by a good response to antifungal therapy and the absence of other pathogens. No underlying diseases were identified and the dog recovered after 3 weeks of therapy with oral itraconazole and topical miconazole. 相似文献