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71.
In vitro culture has great potential for the propagation of freshwater mussels in both commercial and conservation aquaculture. The use of in vitro techniques precludes the need for host fish, thus decreasing costs and increasing efficiency. However, protocols are still lacking for many species that grow substantially during the parasitic stage. In this study, we tested the effects of taurine addition, serum type and source of lipids on the survival rate and increase in length of Margaritifera margaritifera larvae during the initial stage of culture (first 11 days of exposure to media). Our results show that taurine has no significant effect on the early survival rate of glochidia; however, the possible importance of this amino acid in subsequent stages is discussed. The use of an emulsified lipid mixture instead of traditional fish oil showed significantly higher rates of survival. Finally, the addition of serum showed variable effects, with both horse serum and newborn calf serum having higher survival in trials using mussel populations from different sources. These findings can contribute to the invention or improvement of in vitro protocols for species growing during infection and at the same time show the potential that early survival assessments could have for the development of in vitro methods in species with long parasitic stages. 相似文献
72.
Karel Novák 《Veterinary immunology and immunopathology》2014,157(1-2):1-11
The exploitation of the genetic factors affecting the health status of farm animals represents an alternative approach to controlling the diseases caused by microbial pathogens. The determination of innate immunity based on the genotype of the germplasm cells is a constraint for specificity but becomes an advantage in breeding schemes. The structural deviations among Toll-like receptors (TLRs), as the most frequently studied innate immunity components, have been documented at all levels, i.e., interspecific, inter- and intravarietal, in the main farm species. The current computational methods facilitate the prediction of the functional consequences of the observed mutations. Subsequently, these predictions can be verified through immunological responsiveness and population-wide association studies. The frequency and haplotype grouping of individual polymorphisms are used to track the origin and selection coefficient as independent indicators of functional changes. The Toll-like receptor variants associated with mastitis and mycobacterial infection have been identified in cattle, consequently, the targeting of these proteins in breeding could contribute to disease control. The range of infections affected by TLR polymorphisms suggests that the improvement of innate resistance is feasible in more species. Thus, the traditional breeds and wild populations should be regarded as the resources of genetic variability accessible for these purposes. 相似文献
73.
Lukáŝ Veteŝník Ivo Papouŝek Karel Halačka Věra Lusková Jan Mendel 《Fisheries Science》2007,73(4):817-822
A Carassius auratus complex from an artificial wetland in the Morava River basin is composed of triploid females. Based on body depth, sampled
females could be divided into two groups: (i) high-dorsal (42.5% of standard length); and (ii) low-dorsal (36.1% of standard
length). Both groups differed also in number of gill rakers (50.2 versus 45.4, respectively). In concordance with morphological differences, genetic analysis proved the existence of two haplotypes
in examined individuals. The first haplotype is bound to the high-dorsal form with higher number of gill rakers. This is the
most frequent haplotype in populations of the C. a gibelio form in the Czech Republic. The second haplotype is characteristic of the low-dorsal form with a lower number of gill rakers.
This haplotype is close to haplotypes described in the C. a. langsdorfii form, which is known from Japan. and its occurrence within haplotypes specified in European territory is sporadic. 相似文献
74.
Karonen M Hämäläinen M Nieminen R Klika KD Loponen J Ovcharenko VV Moilanen E Pihlaja K 《Journal of agricultural and food chemistry》2004,52(25):7532-7540
The anti-inflammatory properties of phenolic pine (Pinus sylvestris L.) bark extract were studied. The pine bark extract was fractionated by liquid-liquid extractions and semipreparative high-performance liquid chromatography to reveal the most potent constituents. The phenolic compositions of three pine bark samples obtained, a crude extract, a chloroform fraction, and a semipreparative fraction, were analyzed using high-performance liquid chromatography with UV diode array detection and/or electrospray ionization mass spectrometry. In addition, eight compounds were isolated and identified by NMR and MS techniques. In total 28 phenolic compounds were identified. The effects of the three pine bark samples on the synthesis of two proinflammatory mediators, nitric oxide and prostaglandin E(2), were measured. It was shown that pine bark contains compounds that inhibit the production of these proinflammatory mediators. 相似文献
75.
Three monovarietal extra virgin olive oils (EVOOs) were subjected to accelerated storage conditions (60 degrees C, dark) representative of the autoxidation process during shelf life. Oxidation markers, i.e., the peroxide value, conjugated dienes, the oil stability index, and minor components, were monitored. The changes in minor components, related to the stage of ongoing oxidation and expressed as a percentage of the induction period (IP), followed a similar pattern in all oils: o-diphenols diminished by the highest rate (halved within 15% of the IP), followed by alpha-tocopherol (halved within 35% of the IP). Carotenoids and chlorophylls were also affected by autoxidation, whereas squalene showed high stability (<20% loss within 100% of the IP). Polar phenols (especially o-diphenols) and alpha-tocopherol were deduced to be the most potent antioxidants of EVOO. They efficiently inhibited oxidative lipid deterioration and subsequent development of sensory defects (rancidity, discoloration), which occurred only after substantial depletion of these antioxidants. Therefore, they could also be used as markers for the oxidative status of EVOO particularly in the early stage of oxidation. 相似文献
76.
Vladimír ustr Dana Elhottov Vclav Kritfek Alena Lukeov Alena Novkov Karel Tajovský Jan Tíska 《European Journal of Soil Biology》2005,41(3-4):69-75
Feeding biology and thermal adaptations of the terrestrial isopod Mesoniscus graniger were studied. M. graniger is a depigmented isopod mainly inhabiting cave systems, although it has also been reported in endogeic (soil) habitats. Physiological adaptations are expected to reflect the unique environmental characteristics of caves, including restricted food sources, and stable microclimate with temperatures not exceeding about 10 °C and high relative humidity. The M. graniger from Domica and Ardovská caves (Slovakian Karst) were investigated. We identified organic deposits with associated microorganisms as sources exploited by M. graniger and assessed how these might supply essential polyunsaturated fatty acids (PUFA) in its nutrition. Algae, fungi and bat guano were found as the most important potential resources of PUFA for isopods. Digestive enzymes amylase, trehalase, saccharase and maltase were confirmed in the whole body homogenates of isopods; neither cellulolytic activity nor activities against xylan, laminaran and lichenan were observed. Amylase, maltase and cellobiase activities were also observed in bacterial strains isolated and cultured from isopod midgut, and may account for the measured whole-animal activities. In an artificial temperature gradient, M. graniger selected temperature 3.5 ± 5.4 °C with lower and upper extremes of –1.5 and 18.5 °C. Respiration, as measured by VO2, was almost independent of temperature between 5 and 10 °C, then increased between 10 and 30 °C. These ecophysiological measures are consistent with adaptation to a stenothermal environment. 相似文献
77.
Cameron RG Savary BJ Hotchkiss AT Fishman ML Chau HK Baker RA Grohmann K 《Journal of agricultural and food chemistry》2003,51(7):2070-2075
A pectin methylesterase (PME) from sweet orange fruit rag tissue, which does not destabilize citrus juice cloud, has been characterized. It is a salt-dependent PME (type II) and exhibits optimal activity between 0.1 and 0.2 M NaCl at pH 7.5. The pH optimum shifted to a more alkaline range as the salt molarity decreased (pH 8.5-9.5 at 50 mM NaCl). It has an apparent molecular mass of 32.4 kDa as determined by gel filtration chromatography, an apparent molecular mass of 33.5 kDa as determined by denaturing electrophoresis, and a pI of 10.1 and exhibits a single activity band after isoelectric focusing (IEF). It has a K(m) of 0.0487 mg/mL and a V(max) of 4.2378 nkat/mg of protein on 59% DE citrus pectin. Deblocking the N-terminus revealed a partial peptide composed of SVTPNV. De-esterification of non-calcium-sensitive pectin by 6.5% increased the calcium-sensitive pectin ratio (CSPR) from 0.045 +/- 0.011 to 0.829 +/- 0.033 but had little, if any, effect on pectin molecular weight. These properties indicate this enzyme will be useful for studying the PME mode of action as it relates to juice cloud destabilization. 相似文献
78.
Nests of birds represent an unusual microhabitat for diverse groups of soil and epigeic invertebrates including millipedes. The millipede faunas of 301 birds nests from 63 localities throughout Slovakia were obtained by heat extraction of the nest substrates. In total 18 species of millipedes were found in 7 different types of nests of 40 bird species. The most frequent millipede species were Polyxenus lagurus and Proteroiulus fuscus. The similarities in the millipede nidifauna depending on the type of nests, ecological characteristics and geographical distribution of millipede species are discussed. 相似文献
79.
80.
González-Rey C Svenson SB Bravo L Siitonen A Pasquale V Dumontet S Ciznar I Krovacek K 《Comparative immunology, microbiology and infectious diseases》2004,27(2):129-139
A total of 73 strains of Plesiomonas shigelloides isolated from humans (24 strains) animals (21 strains) and aquatic environment (28 strains) were determined for their O:H serotype and susceptibility to 18 anti-microbial substances and to the vibriostatic agent O/129. Of all strains, 86.3% were typeable by the O and 94.5% by the H anti-sera used. The serotype distribution was heterogeneous within a country and between the countries. Of the 57 different serotypes identified, O11:H2 (2 strains), O22:H3 (4 strains), O35:HH11 (2 strains), O52:H3 (2 strains) and O90:H6 (2 strains) were found among isolates from humans and animals (mainly in cats) in Finland and Cuba, and O23:H1a1b (3 strains) among isolates from environmental sources in Slovak Republic and Italy. Most (93-100%) of all strains were susceptible to all anti-microbials tested but resistant (92-96%) to the broad-spectrum penicillins (ampicillin, mezlocillin). No correlation between anti-microbial resistance patterns and serotypes was found. 相似文献