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61.
The persistence of Sphaeropsis sapinea, Leptographium serpens and Heterobasidion annosum s.s. in artificially inoculated pine branch pieces (S. sapinea and L. serpens) and wood blocks (L. serpens and H. annosum s.s.) was investigated in order to discuss the alternative of leaving coarse woody debris in stands of Italian stone pine (Pinus pinea). Also, natural colonization by S. sapinea of pine cones of different ages was assessed. Methods used for inoculating branch pieces and wood blocks were highly effective for all fungi. Type of a forest stand in which branch pieces and wood blocks have been incubated did not affect the persistence of the pathogens in the inoculated samples. For branch pieces, the success of re-isolation of L. serpens dropped as the sample incubation time increased, while S. sapinea was always successfully (100%) re-isolated (even 12 months after the inoculation). L. serpens and H. annosum s.s. were re-isolated from most of the buried wood blocks (from more than 95% samples) up to 3 months following the inoculation. Of the observed P. pinea cones (in most cases, more than 2 years old), 74% were naturally infected byS. sapinea. All three investigated pathogens were able to survive in dead plant tissues for long periods of time (at least for several (3–12) months). The persistence of these pine-pathogenic species in dead plant material questions the feasibility of leaving coarse woody debris in managed Italian stone pine forests meant for landscape conservation and leisure activities.  相似文献   
62.
Background: Colostrum is the first secretion produced by mammary glands during the hours immediately preceding and succeeding parturition. This secretion differs from milk and represents an essential vehicle of passive immunity,prebiotic compounds and growth factors involved in intestinal development. Most of the literature concerning colostrum composition refers mainly to human and cow; and little is known about pig colostrum metabolome and how it varies between pig breeds and different farrowing parity. Thus, the aim of the present research is to provide new information about pig colostrum composition and the associations between metabolites, the sows' breed and the survival and growth rates of their litters.Results: Colostrum samples were gathered from 58 parturitions of sows belonging to three different breeds chosen for their importance in Italian heavy pig production: 31 Large White, 15 Landrace and 12 Duroc respectively. The defatted and ultrafiltered colostrum samples were analysed using1 H–NMR spectroscopy. Principal Components Analysis(PCA) was assessed on the obtained spectra. In addition, using a Stepwise Regression and a Linear Regression analyses the metabolites named after the signals assignment were tested for their associations with piglets' performances.Twenty-five metabolites were identified, comprehending monosaccharides, disaccharides(such as lactose), organic acids(lactate, citrate, acetate and formate), nitrogenous organic acids(such as creatine) and other compounds,including nucleotides. PCA results evidence a clustering due to breed and season effects. Lactose was the main compound determining the assignment of the samples into different clusters according to the sow breed. Furthermore, some metabolites showed to be associated with piglets' performance and survival traits: acetate and taurine were positively related to litter weight gain and piglets' survival rate, respectively, while dimethylamine and cis-aconitate were linked to new-borns' impaired ability to survive.Conclusions: The results obtained suggest that colostrum composition is affected by breed, which, together with environmental conditions, may cause changes in colostrum metabolites content with possible consequences on piglets' performances. Among the identified metabolites, acetate, taurine, dimethylamine and cis-aconitate showed consistent associations with piglets' survival rate and litter weight gain, implying that these compounds may affect new-borns' ability to survive.  相似文献   
63.
Headspace solid-phase microextraction (HS-SPME) -gas chromatography using flame ionization detection and multivariate analysis were applied to the study of the specificity of protected designation of origin (PDO) virgin olive oils produced in a southern French region (Alpes-Maritimes) based on their volatile compounds. A total of 35 PDO olive oils from Nice, 6 commercial oils, and 12 other French PDO olive oils were analyzed. Recorded data were subjected to principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). The method developed here was able to perfectly distinguish different qualities of olive oils. Representative samples from each class obtained by chemometric treatment were analyzed by HS-SPME and GC-MS. PCA and SIMCA of chromatographic data were related to sensory analysis and led to a better understanding of the chemical features and observed sensory effects of olive oils.  相似文献   
64.
Differential scanning calorimetry (DSC) was used to study the thermal behavior of authentic honeys (Lavandula, Robinia, and Fir honeys) and industrial sugar syrups. Thermal or thermochemical parameters such as the glass transition temperature (Tg), enthalpies of fusion (DeltaH(fus)), and heat capacity variation (DeltaC(p)) were measured. The syrups and honeys showed significant differences in thermal phenomena, as well as in their amplitude and position on the temperature scale. Results showed good reproducibility of the method for all samples studied. The effect of adulteration of honey with different amounts of syrup (5, 10, 20, 40, and 60%) was investigated. A linear relationship was found between the percentage of added syrup and the glass transition temperature. A similar relationship was obtained from the enthalpy of fusion results in the temperature range of 40-90 degrees C. Under applied conditions, the effects of adulteration of honeys by industrial syrups appeared to be detectable from a level as low as 5%.  相似文献   
65.
This paper reports the optimization of an electrochemical bioassay for the determination of chlorpyrifos-methyl and its application to the analysis of grape and vine leaf samples treated with that pesticide. The analytical method was based on electrochemical determination of the extent of the inhibition exerted by the pesticide on acetylcholinesterase using the substrate acetylthiocholine. Two similar calibration plots were obtained, in the range of 1-300 ng/mL, respectively, for chlorpyrifos-methyl in pure standard form and in the commercial preparation Reldan, with comparable coefficients of variation (CV) in the range of 10% < CV < 20%. After an insecticide treatment, samples were analyzed to evaluate its persistence both in grapes and in vine leaves. Samples were evaluated using different extraction procedures: one based on solvent extraction of pesticide residue from grapes and the other based on aqueous extraction from vine leaves using phosphate buffer. The grape solvent extracts were analyzed using both gas chromatography and electrochemical bioassay, whereas the vine leaf buffer extracts were analyzed using the electrochemical bioassay. Quantitative analysis of chlorpyrifos-methyl determined in the two samples, with the electrochemical bioassay, showed a comparable decrease profile over the experimental period.  相似文献   
66.
67.
Serum amyloid A (SAA), the major equine acute-phase protein, is often measured after the race to investigate whether poor performances could depend on inflammation. The aim of this study was to assess whether there is an increase in concentration of SAA in serum samples collected from 12 clinically healthy Standardbred horses 1 hour after a standard race. Exercise induced an increase in red blood cells, hematocrit, and total proteins but not in SAA. However, a two- to threefold increase of SAA concentration as compared with prerace values was found in three horses. In conclusion, the concentration of SAA in most of the samples collected 1 hour after the race remains unchanged as compared with prerace samples. However, individual variability in response to exercise exists. The evaluation of SAA immediately after the race is not clinically useful.  相似文献   
68.
The aim of this study was to quantify and compare interferon-γ (IFN-γ) concentrations in the serum of clinically normal cats infected with feline coronavirus (FCoV) with its concentration in the sera and effusions of cats with feline infectious peritonitis (FIP), a disease associated with infection with a mutated form of FCoV.Clinically normal FCoV-infected cats living in catteries with a high prevalence of FIP had the highest serum IFN-γ concentrations. The serum concentration of IFN-γ was not significantly different in cats with FIP compared with clinically normal FCoV-infected animals living in catteries with a low prevalence of the disease. Moreover, the concentration of IFN-γ was significantly higher in the effusions than in the serum of cats with FIP, probably due to IFN-γ production within lesions. These findings support the hypothesis that there is a strong, ‘systemic’ cell mediated immune response in clinically normal, FCoV-infected cats and that a similar process, albeit at a tissue level, is involved in the pathogenesis of FIP.  相似文献   
69.
In order to investigate the genotypes of Giardia duodenalis from domestic and farm animals in Italy, 21 Giardia isolates, 17 from dogs, 1 from cat and 3 from dairy calves, were genetically characterised by SSU-rRNA gene sequencing. Among dogs, 76.5% of isolates showed the dog-specific genotypes (Assemblages C, D and C/D mixed Assemblage) and 23.5% exhibit potential zoonotic genotypes (Assemblage A and A/C mixed Assemblages). The cat isolate belonged to assemblage A, whereas the sequences among the isolates from calves were found to correspond to hoofed-livestock genotype, namely Assemblage E. These findings suggest that infection of humans by zoonotic genotypes from domestic animals could be of low epidemiological significance, although possible. The present study represents the first contribute to the knowledge of G. duodenalis genotypes in domestic and farm animals from Italy.  相似文献   
70.
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