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71.
Snia J. Amarante Marcelo D. Catarino Catarina Maral Artur M. S. Silva Rita Ferreira Susana M. Cardoso 《Marine drugs》2020,18(11)
Microwave-assisted extraction (MAE) was carried out to maximize the extraction of phlorotannins from Fucus vesiculosus using a hydroethanolic mixture as a solvent, as an alternative to the conventional method with a hydroacetonic mixture. Optimal MAE conditions were set as ethanol concentration of 57% (v/v), temperature of 75 °C, and time of 5 min, which allowed a similar recovery of phlorotannins from the macroalgae compared to the conventional extraction. While the phlorotannins richness of the conventional extract was slightly superior to that of MAE (11.1 ± 1.3 vs. 9.8 ± 1.8 mg PGE/g DWextract), both extracts presented identical phlorotannins constituents, which included, among others, tetrafucol, pentafucol, hexafucol, and heptafucol structures. In addition, MAE showed a moderate capacity to scavenge ABTS•+ (IC50 of 96.0 ± 3.4 µg/mL) and to inhibit the activity of xanthine oxidase (IC50 of 23.1 ± 3.4 µg/mL) and a superior ability to control the activity of the key metabolic enzyme α-glucosidase compared to the pharmaceutical drug acarbose. 相似文献
72.
Torsein M Lindberg A Sandgren CH Waller KP Törnquist M Svensson C 《Preventive veterinary medicine》2011,99(2-4):136-147
The aim of this study was to identify possible risk factors for 1-90 day calf mortality in large Swedish dairy herds. Sixty herds with a herd size of ≥160 cows were visited once between December 2005 and March 2006. Thirty herds were known to have low mortality (LM) and 30 were known high mortality herds (HM). Upon the visit, data about housing and management was collected from interviews with personnel responsible for the calves. The herd status regarding the calves' passive transfer (total protein), levels of α-tocopherol, β-carotene and retinol, and excretion of faecal pathogens (Cryptosporidium spp., Escherichia coli F5, rota and corona virus) was evaluated based on targeted sampling of high risk calf groups; in each herd, blood and faecal samples were collected from calves 1-7 and 1-14 days old, respectively. Similarly, the herd status regarding clinical respiratory disease in calves and history of respiratory virus exposure was evaluated based on lung auscultations and blood samplings of calves 60-90 days old. The median calf mortality risk (in calves 1-90 days of age) among HM herds was 9% (Range: 6-24%) and among LM herds 1% (Range: 0-2%). LM and HM herds were compared using five logistic regression models, covering potential risk factors within different areas: "Disease susceptibility", "Factors affecting the gastrointestinal tract", "Factors related to transmission of infectious disease", "Hygiene" and "Labour management". The percentage of calves, 1-7 days old, with inadequate serum concentrations of α-tocopherol and β-carotene were significantly higher in HM herds compared to LM herds and also associated with higher odds of being a HM herd (OR=1.02; p=0.023 and OR=1.05; p=0.0028, respectively). The variable "Average number of faecal pathogens in the sampled target group" was significantly associated with higher odds of being a HM herd (OR=4.65; p=0.015), with a higher average in HM herds. The percentage of calves with diarrhoea treated with antibiotics was significantly higher in HM herds and was associated with higher odds of being a HM herd (OR=1.08; p=0.021). The median age at death of calves in the age interval 1-90 days that died during a one-year period was significantly lower among HM herds (13 days) than in LM herds (24 days) (p=0.0013) The results indicate that gastrointestinal disorders may be an important cause of calf mortality in large Swedish dairy herds. Furthermore, our study provides additional indications that fat soluble vitamins might play an important role for calf health. 相似文献
73.
Pacheco MA Escalante AA Garner MM Bradley GA Aguilar RF 《Veterinary parasitology》2011,182(2-4):113-120
The avian haemosporidian parasites (phylum Apicomplexa) are taxonomically diverse and cosmopolitan in distribution; infecting most bird families. Sources of concern are reports of clinical haemosporidian infections in birds kept as part of zoo and aviary collections. Recently, severe and acute mortality episodes have been reported in masked bobwhite quail (Colinus virginianus ridgwayi), an endangered subspecies from the American Southwest. Two hundred and five eggs of the captive flock held in Arivaca, Arizona, were hatched at a zoo in the American Southwest. Thirty-four sub-adult or adult animals had lesions associated with tissue phases of haemoparasites, especially vasculitis, ventricular leiomyositis and ulcerative pododermatitis. Molecular techniques applied to blood collected from the zoo's last twelve remaining animals resulted in the detection of a Plasmodium juxtanucleare-like and Haemoproteus sp. parasites. A Raven (Corvus corax), in a contiguous exhibit, was positive for the same P. juxtanucleare-like parasite, but remained asymptomatic for three years following detection. These findings indicate that other birds in the exhibit within the zoo premises could act as reservoirs. We conclude that haemosporidian infections could be a factor in the demise of the captive masked bobwhite quails housed at the zoo. We suggest that active surveillance for haemoporidian parasites should be incorporated as a precaution to ex situ conservation efforts of susceptible endangered species. 相似文献
74.
Rafael de Paula Xavier de Andrade Marcelo de Andrade Ferreira Stela Antas Urbano Marcílio de Azevedo Sabrina Carla Rodrigues Félix Michelle Christina Bernardo de Siqueira Felipe José Lins Alves Juana Catarina Cariri Chagas 《Tropical animal health and production》2013,45(5):1191-1196
The objective of this study was to evaluate the effect of replacing Tifton 85 hay (0, 33, 66, or 100 %) with by castor bean hulls on the intake and nutrient digestibility and performance of 28 noncastrated lambs, averaging 7 months in age, 19.5?±?2.0 kg average live weight, fed on diets based on forage cactus. The animals were housed in individual pens for 100 days. The digestibility trial occurred 40 days after the start of the performance using LIPE® as an external indicator for estimating fecal dry matter production. The replacement of hay with Castor beans hulls linearly decreased the intakes of dry matter, neutral detergent fiber, organic matter, and crude protein and reduced the digestibility coefficients of the dry matter, neutral detergent fiber, organic matter content, crude protein, and total digestible nutrient content. The hot carcass and true carcass yields were not influenced by the treatments and the feed conversion increased linearly. The empty body weight, live weight at slaughter, hot and cold carcass weights, total gain, and average daily gain decreased linearly with the replacement. The replacement of Tifton 85 hay with castor bean hulls reduced the intake of dry matter, crude protein and energy, consequently reducing the performance of the animals. However, as the regression coefficients were of low magnitude, data were subjected to analysis of variance and means were compared using the Dunnett test with diet without castor bean hulls set as the control treatment. The Tifton 85 hay can be replaced up to 66 % by castor bean hulls in finishing diets for lambs. 相似文献
75.
Catarina Pereira Fernando Caldeira Jorge Mark Irle José Maria Ferreira 《Journal of Wood Science》2006,52(4):311-317
Data are presented on the effects that cork, blue gum, or maritime pine, all grown in Portugal, have on cement setting. These
materials were mixed with cement either without any treatment or after being extracted previously with a range of solvents
(ranging from nonpolar to very polar). Other experiments were carried out in which extractives or calcium chloride were added
to the cement paste. All lignocellulosic substrates have detrimental effects on cement setting, which is mostly seen by a
delay in attaining the maximum temperature in the process. However, the addition of calcium chloride was able to overcome
this disadvantage. Extraction of the substrates with some polar extraction agents before addition to the cement paste only
slightly improved compatibility, and the addition of water-based extractives to a cement paste affects the setting much less
than the lignocellulosic material by itself. Several thermal compatibility indices, including a new index proposed in this
article, were calculated from data taken from temperature profiles, and conclusions are presented on the performance of the
setting systems, as compared with a neat cement paste. In addition, comments are expressed on the level of accuracy offered
by the indices applied in this study, and how such accuracy can be checked or improved by matching them to the physical properties
of the wood-cement composites. 相似文献
76.
M. Luisa Valdeira Catarina Bernardes B. Cruz A. Geraldes 《Veterinary microbiology》1998,60(2-4):131-140
African swine fever virus (ASFV) enters Vero cells by adsorptive endocytosis [Valdeira, M.L., Geraldes, A., 1985. Morphological study on the entry of African swine fever virus into cells, Biol. Cell. 55, 35–40]. Electron microscopy of a lysosomotropic drug-controlled penetration indicated that this step takes place in the endosomes, after fusion between the viral envelope and the limiting membrane of the endosome. Inhibition studies with colcemid, cytochalasin B, sodium azide, dinitrophenol, lysosomotropic weak bases, and the ionophore monensin, showed that the virus uptake is largely independent of cytoskeletal and lysosomal function, but dependent on oxidative phosphorylation. Some protease inhibitors inhibited viral replication at an early step, indicating that the initiation of infection depends on a viral proteolytic cleavage. 相似文献
77.
Comparison of portuguese soils from different geographical regions using physicochemical,biological and biochemical parameters 总被引：1，自引：1，他引：0
78.
Cortisol and finfish welfare 总被引：1，自引：0，他引：1
Ellis T Yildiz HY López-Olmeda J Spedicato MT Tort L Øverli Ø Martins CI 《Fish physiology and biochemistry》2012,38(1):163-188
Previous reviews of stress, and the stress hormone cortisol, in fish have focussed on physiology, due to interest in impacts
on aquaculture production. Here, we discuss cortisol in relation to fish welfare. Cortisol is a readily measured component
of the primary (neuroendocrine) stress response and is relevant to fish welfare as it affects physiological and brain functions
and modifies behaviour. However, we argue that cortisol has little value if welfare is viewed purely from a functional (or
behavioural) perspective—the cortisol response itself is a natural, adaptive response and is not predictive of coping as downstream
impacts on function and behaviour are dose-, time- and context-dependent and not predictable. Nevertheless, we argue that
welfare should be considered in terms of mental health and feelings, and that stress in relation to welfare should be viewed
as psychological, rather than physiological. We contend that cortisol can be used (with caution) as a tractable indicator
of how fish perceive (and feel about) their environment, psychological stress and feelings in fish. Cortisol responses are
directly triggered by the brain and fish studies do indicate cortisol responses to psychological stressors, i.e., those with
no direct physicochemical action. We discuss the practicalities of using cortisol to ask the fish themselves how they feel
about husbandry practices and the culture environment. Single time point measurements of cortisol are of little value in assessing
the stress level of fish as studies need to account for diurnal and seasonal variations, and environmental and genetic factors.
Areas in need of greater clarity for the use of cortisol as an indicator of fish feelings are the separation of (physiological)
stress from (psychological) distress, the separation of chronic stress from acclimation, and the interactions between feelings,
cortisol, mood and behaviour. 相似文献
79.
Conceição LE Aragão C Dias J Costas B Terova G Martins C Tort L 《Fish physiology and biochemistry》2012,38(1):119-141
Little research has been done in optimizing the nitrogenous fraction of the fish diets in order to minimize welfare problems.
The purpose of this review is to give an overview on how amino acid (AA) metabolism may be affected when fish are under stress
and the possible effects on fish welfare when sub-optimal dietary nitrogen formulations are used to feed fish. In addition,
it intends to evaluate the current possibilities, and future prospects, of using improved dietary nitrogen formulations to
help fish coping with predictable stressful periods. Both metabolomic and genomic evidence show that stressful husbandry conditions
affect AA metabolism in fish and may bring an increase in the requirement of indispensable AA. Supplementation in arginine
and leucine, but also eventually in lysine, methionine, threonine and glutamine, may have an important role in enhancing the
innate immune system. Tryptophan, as precursor for serotonin, modulates aggressive behaviour and feed intake in fish. Bioactive
peptides may bring important advances in immunocompetence, disease control and other aspects of welfare of cultured fish.
Fishmeal replacement may reduce immune competence, and the full nutritional potential of plant-protein ingredients is attained
only after the removal or inactivation of some antinutritional factors. This review shows that AA metabolism is affected when
fish are under stress, and this together with sub-optimal dietary nitrogen formulations may affect fish welfare. Furthermore,
improved dietary nitrogen formulations may help fish coping with predictable stressful events. 相似文献
80.