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1.
Vitamin E supplementation has become a common procedure to promote growth and health and improve the qualitative characteristics of farm animals. It has been demonstrated to be an efficient strategy for improving their reproductive function. Germ cells are particularly vulnerable to oxidative damage and may thus require additional antioxidant protection. The aim of this review is to give a comprehensive overview of the current knowledge of the biochemistry and physiology of vitamin E; successively, the effect of this compound on the reproductive activity of rabbit buck is accurately described. In particular, this review examines studies on the effects of animal age, dose and duration of vitamin E supplementation, as well as the co-supplementation with selenium, vitamin C and polyunsaturated fatty acids. Several investigations have shown beneficial effects in bucks supplemented with vitamin E levels higher than the standard dietary requirement (50 mg/kg) particularly when the semen is stored. However, the exact dietary intake of vitamin E should be decided according to specific tissue needs for the individual vitamin E forms and the specific saturation markers. 相似文献
2.
Gabriela Claudia Cangahuala-Inocente Lírio Luiz Dal Vesco Douglas Steinmacher Antonio Carlos Torres Miguel Pedro Guerra 《Scientia Horticulturae》2007
Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA3 (1 μM) and activated charcoal (1.5 g L−1) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA3 (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets. 相似文献
3.
Alessandro Zanzotto Federica Autiero Diego Bellotto Gianluca Dal Cortivo Gianluca Lucchetta Michele Borgo 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(2):183-192
During a 6-year study, grapevine propagation materials and young grapevines were analysed to evaluate the presence of internal
wood discolouration and the occurrence of fungal species involved in Petri disease. The intensity of wood discolouration increased
with the ageing of the plants. The maximum incidence of dark streaks was observed in the rootstock while necrosis originating
from buds or nodes were notably present in the trunk and cordon of older vines. In contrast, the highest levels of brown-red
halo symptoms, defined as discoloured areas around the pith, were recorded in the early growth stages. Phaeoacremonium spp. and Phaeomoniella chlamydospora were usually isolated from the rooted-grafts and the 3-year old plants, respectively. The number of infected grapevines increased
with age. Most of the P. chlamydospora strains were isolated from dark streaks or dots, while Phaeoacremonium spp. were detected in brown-red halo symptoms and other symptomatic or asymptomatic wood. The greatest incidence of the two
fungal taxa was recorded in the lower parts of the grapevine, including the roots and rootstock. 相似文献
4.
Large‐scale fuzzy rule‐based prediction for suitable chestnut ink disease sites: a case study in north‐east Italy 下载免费PDF全文
In the past few decades, economic interest in the cultivation of chestnuts for both timber and nut production has resurfaced in the Mediterranean area. However, chestnut cultivation has suffered in recent years from the spread of exotic pests, such as the gall wasp Dryocosmus kuriphilus, and from the resurgence of previously present diseases, most likely due to anomalous climate dynamics. This is the case with chestnut ink disease, caused by the soilborne pathogens Phytophthora cinnamomi and P. cambivora. Scientific and technical support in monitoring and management, that utilizes new forecasting approaches incorporating related environmental variables, is therefore essential. The main aim of this study was to develop a mathematical model assessing the potential for the establishment of chestnut ink disease at a large scale. Towards this goal, fuzzy rule‐based theory was applied to the environmental variables associated with host presence, pathogens' ecological niches and ink disease symptoms expression. The effectiveness of the rule‐based modelling outcomes, provided with uncertainty maps to facilitate their correct interpretation, was confirmed by detailed field data collected from a large chestnut‐growing area where ink disease has been increasing in recent years. The final model gave consistent predictions for disease presence. For this reason, it represents a flexible and valuable decision‐support tool to forecast which sites are at risk from CID. 相似文献
5.
Claudio Chiesa Alma Dal Prà Giancarlo Guarneri Sandro Penso Leonardo Rodella Laura Volterra Adriano Zugno 《Water, air, and soil pollution》1987,34(3):241-244
Results from examining shellfish collected from ‘safe’ (2–34Escherichia coli/100 mL) and ‘unsafe’ (> 34E. coli/100 mL) waters for the presence ofYersinia enterocolitica and related bacteria are reported. The recovery of these microorganisms was low in bivalve mollusks destined for food consumption, high in those derived from prohibited areas. No human pathogenic bio-serogroup f Yersinia was found during the entire survey. 相似文献
6.
7.
Maria Laura Gabriel Kuniyoshi Rafaela Nunes da Silva‐Gomes Bruna Tereza Thomazini Zanella Lucilene Delazari dos Santos Maeli Dal‐Pai‐Silva 《Aquaculture Research》2020,51(3):1101-1112
Here, we aimed to study the slow muscle of the fish Piaractus mesopotamicus submitted to 30 days of fasting (D30) followed by 1 day (D31) or 30 days of refeeding (D60). Histological analysis of fibre diameter was performed in D30 and D60. The gene expression of parvalbumin (pvalb), atrogenes (murf1a, murf1b, mafbx) and anabolic genes (igf‐1, mtor) was analysed using RT‐qPCR in D30, D31 and D60. The proteome was obtained by shotgun proteomics at D30 and D60, and the set of differentially expressed proteins was analysed by bioinformatics. In all experiments, the control was regularly fed fish. The histological analysis showed no changes in muscle fibre diameter. The expression of catabolic and anabolic genes was not changed, except for the downregulation of igf‐1 in D30 and of mafbx in D31. The expression of pvalb was not changed in D30 and D60 but was decreased in D31. The proteomic analysis identified 169 proteins in D30 (24 upregulated and 18 downregulated) and 170 proteins in D60 (17 upregulated and 21 downregulated); many of them were related to energetic metabolism and intracellular Ca2+ homoeostasis. Overall, our results indicate that the slow‐twitch muscle presented few changes upon prolonged fasting and refeeding condition. 相似文献
8.
9.
Bioassays were conducted in stored grains to evaluate the combined use of the entomopathogenic fungus Beauveria bassiana, diatomaceous earth (DE) and fenitrothion against adults of Rhyzopertha dominica and Tribolium castaneum. The insecticide agents were applied to wheat as follows: the fungus at 1 × 108 conidia/kg of wheat, DE at 3 g/kg of wheat and fenitrothion at a rate of 0.15 ml/kg of wheat (25% of field dose rate). Surviving insects and progeny production were monitored at thirty-day intervals until four months. For both insect species, significantly less progeny was produced on wheat treated with fenitrothion and DE + B. bassiana formulations in comparison with controls. The effect of insecticides on the grain damage, germination power of wheat and bulk density was also evaluated. After four months, B. bassiana mixed with DE reduced the damaged insect grains by 50% in comparison with both fenitrothion and control treatments. Trials using DE caused a reduction in bulk density while there were no significant differences for germination testing between treatments. 相似文献
10.
Edith K. Hüttner Fabio Dal Bello Emanuele Zannini Jean Titze Steffen Beuch Elke K. Arendt 《Cereal Chemistry》2011,88(6):602-608
The breadmaking potential of six oat varieties was compared with and related to their physicochemical properties. The most significant differences in the bread characteristics were found in the crumb structure. The varieties Buggy, Energie, and Zorro resulted in good bread quality with an even gas‐cell distribution characterized by a high number of relatively small pores. In contrast, Typhon, Ivory, and Nord 08/311 each had a large hole in the center of the crumb and accordingly poor quality. Breads differed little in specific volume, bake loss, and density. Rheological analysis revealed positive effects of low batter resistance to deformation on oat bread quality. On the basis of the physicochemical characterization, protein and fat contents were identified as key factors responsible for differences observed in bread quality, provided that starch damage and water‐hydration capacity were low. Additionally, high setback and final viscosity, as determined by Rapid Visco Analyser (RVA) analysis, positively affected oat bread quality. High α‐amylase activity was found to influence negatively the breadmaking performance of oats. Overall, protein, fat, dietary fiber content, starch pasting properties, and α‐amylase activity were responsible for the breadmaking properties of oat varieties. 相似文献