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71.
Previous studies on the oxidative stress in swine indicated a strong link between the values of reactive oxygen metabolites (ROMs), the subsequent antioxidant adaptive response (OXY) and the genetic selection. Such findings, mainly related to a cardiovascular inadequacy in lean, large muscle blocks and fast growing breeds, is associated with specific metabolic diseases such as porcine stress syndrome and mulberry heart disease. In this study, we investigated the oxidative stress parameters to trace the genetics of Cinta Senese (CS) pigs, a historical breed free-range reared in Siena countryside. Sera from CS (n = 24) and Large White x CS (LW x CS) (n = 24) groups around 120 kg body weight fed the same diet were sampled at slaughter. Sera from wild boars (WB) (n = 24) hunted in the same district were also considered. ROMs and OXY were evaluated in the three groups of swine. Significant differences by one-way anova (P < 0.05) between groups were found for both procedures. ROM levels were lower in WB (9.79 +/- 5.76 mm H2O2) and CS (18.02 +/- 7.42 mm H2O2), and highest in LW x CS (42.78 +/- 8.61 mm H2O2). OXY values ranged from 271.37 +/- 50.90 microm neutralized HOCl (WB) to 343.21 +/- 57.45 microm neutralized HOCl (LW x CS). Results indicated that the evaluation of the oxidative stress can effectively trace the CS pigs, thus aiding in preserving the overall specific traits of such a historical animal.  相似文献   
72.
The ability of pigs to neutralize the reactive oxygen species (ROS) plays a key role in their welfare. Two micromethods were developed to evaluate the oxidative stress and the anti-oxidative response in sera. We tested these methods for linearity, repeatability and reproducibility. A hydroxyl radicals (HR) test, based on the Fenton reaction, showed a linearity between 0.26 and 4.5 mM H2O2 (r = 0.997), with a coefficient of repeatability (CVr) of 1.9 and a coefficient of reproducibility (CVR) of 2.9. An anti-oxidant power (AOP) test, based on the capability of sera to neutralize a titred hypochlorous acid solution (HClO), showed a linearity between 55 and 880 microM HClO neutralized (r = 0.984), with CVr = 3.1 and CVR = 4.9. We assessed the applicability of such tests in field conditions on three different farms. Farm A recorded a positive anamnesis of Mulberry heart disease. Dietary Vitamin E supplementation was given at 50 p.p.m. in farms A and B and at 150 p.p.m. in farm C, respectively. The group from farm A showed HR sera levels higher than those of farm B and farm C (farm A, mean = 31.61 +/- 2.87 mM H2O2, n = 10; farm B, 28.53 +/- 2.30, n = 10; and farm C, 25.63 +/- 1.03, n = 10; P < 0.01). The AOP test was not able to discriminate between farms. The AOP levels found (mean = 472.50 microM HClO neutralized: n = 30) probably represent the maximum response of the organism to compensate the oxidative stress. HR and AOP are stable in sera stored at +4 degrees C. We discuss the application of such methods for the assessment of farmed animals' welfare.  相似文献   
73.
74.
Virgin olive oils from percolation (first extraction) have been compared with the corresponding oils from centrifugation (second extraction). The former were characterized by (i) higher contents of total phenols, o-diphenols, hydroxytyrosol, tyrosol-aglycons, tocopherols, trans-2-hexenal, total volatiles, and waxes; (ii) higher values of resistance to autoxidation and of turbidity; (iii) higher sensory scores; (iv) higher ratios of campesterol/stigmasterol, trans-2-hexenal/hexanal, and trans-2-hexenal/total volatiles; (v) lower contents of chlorophylls, pheophytins, sterols, and aliphatic and triterpene alcohols; (vi) lower alcoholic index and color indices; (vii) similar values of acidity, peroxide index, and UV (ultraviolet) spectrophotometric indices; (viii) similar percentages of saturated and unsaturated fatty acids, triglycerides, and diglycerides; and (ix) similar values of glyceridic indices. Stigmastadienes, trans-oleic, trans-linoleic, and trans-linolenic acid isomers were not detected in the two genuine oil kinds. Hence, the qualitative level of the first extraction oil was superior to the second extraction one.  相似文献   
75.
Leaf spot of tomato, incited by Pseudomonas syringae pv. syringae, has been reported recently in Italy on grafted and non-grafted tomato plants (scion Cuore di Bue, rootstock Solanum lycopersicum x Solanum hirsutum cv. Beaufort). In some greenhouses, more than 80% of plants were affected, with a marked reduction in yield. This work was undertaken in order to understand the effect of the number of hours of incubation at high relative humidity (r.h.) and temperature as well as the effect of the presence of wounds at infection time on the development of leaf spot. A difference in sensitivity to leaf spot was observed in the various cultivars tested, in terms of severity of P. syringae pv. syringae, with “Cuore di Bue” being the most susceptible of these cultivars. The development of leaf spot is mostly favored by the presence of wounds, at temperatures between 15 and 20°C. The severity of the disease is lower at 10 and 25°C and very low at 30°C. Under the most favorable temperature conditions, the presence of wounds is sufficient to allow the development of the pathogen immediately upon incubation at high r.h. The effect of wounds and the relatively low requirement of hours of incubation at high r.h. suggest the need for careful management and handling of plants when temperatures range between 15 and 25°C, and particularly within 15 and 20°C. All operations carried out, particularly at transplant and immediately after, should avoid the creation of wounds.  相似文献   
76.

Key message

Compared to the traditional approach, applying micrometric image analysis to fine root samples of Fagus sylvatica with subsequent data treatment through principal component and cluster analysis yielded specific diameter sizes for fine root sub-classes having better resolution of the corresponding branching orders, and a more coherent relationship with the values of annual production and turnover rate.

Context

Fine root traits are poorly understood, impeding an accurate representation of terrestrial biogeochemical models. Traditionally used, arbitrary diameter thresholds lead to a misestimation of fine root traits such as branching order, environmental relationship, annual production, and turnover rate.

Aims

Here, we present, as modification of the traditional method, an integrated approach to segregate, at high-resolution, fine root populations of Fagus sylvatica into new diameter sub-classes that better correspond with the traits mentioned above.

Methods

Samples, collected with a sequential soil coring method, were subjected to a micrometric image analysis, and resultant data were treated with principal component and cluster analysis.

Results

Results showed that fine roots were distributed into diameter-size sub-classes (0–0.3 mm, 0.3–1 mm, and 1–2 mm) different from those determined by traditional methods (0–0.5 mm, 0.5–1 mm, and 1–2 mm). New sub-classes provided a better resolution of the corresponding branching-orders, and the values of annual production and turnover rate were more coherent with diameter class and soil depth. Moreover, new sub-classes provided a more precise match with soil temperature than traditional methods.

Conclusion

Our method may help to unveil fine root dynamics and development, reduce data analysis time, and make the diameter-based classification more precise and trustworthy even in the case of non-intact samples.
  相似文献   
77.
The strategy for breeding blueberries has been based on phenotypic selection without accounting for pedigree correlation information. A central premise of classical quantitative genetics is that through knowledge of the relationships among individuals in a population, we can make inferences about breeding values (BVs), estimate genetic parameters, and support phenotypic selection. Genetic evaluations using best linear unbiased prediction (BLUP) and restricted maximum likelihood (REML) are founded on pedigree information and have been the standard method used in livestock and forest breeding. Despite theoretical and practical benefits, their application in blueberry breeding programs remains unexploited. The objective of this study was to evaluate the use of REML/BLUP in the University of Florida blueberry breeding program in order to estimate genetic parameters and predict BVs of primary selection traits. To do this, we collected phenotypic data for eight selectable traits (yield, flower bud density, fruit weight, fruit firmness, fruit diameter, fruit soluble solids, fruit pH, and fruit scar diameter) from 1996 individuals. The highest narrow-sense heritabilities were found for fruit weight, scar diameter, and yield. The majority of genetic correlations between traits were under 0.20. The largest genetic gain was achieved when selections from early stages were used as parents and the top 5% of the population was selected. Compared to traditional phenotypic selection, our results are evidencing of the importance of implementing REML/BLUP to estimate genetic parameters that help and support the breeding strategy and maximize genetic gains.  相似文献   
78.
Nitric oxide (NO) is generated via the oxidation of l-arginine by the enzyme NO synthase (NOS) both in vertebrates and invertebrates. Three NOS isoforms, nNOS, iNOS and eNOS, are known in vertebrates, whereas a single NOS isoform is usually expressed in invertebrates, sharing structural and functional characteristics with nNOS or iNOS depending on the species. The present paper is focused on the constitutive Ca2+/calmodulin-dependent nNOS recently sequenced by our group in the neogastropod Stramonita haemastoma (ShNOS). In this paper we provide new data on cellular distribution of ShNOS in the CNS (pedal ganglion) and peripheral organs (osphradium, tentacle, eye and foot) obtained by WB, IF, CM and NADPHd. Results demonstrated that NOS-like proteins are widely expressed in sensory receptor elements, neurons and epithelial cells. The detailed study of NOS distribution in peripheral and central neurons suggested that NOS is both intracellular and presynaptically located. Present findings confirm that NO may have a key role in the central neuronal circuits of gastropods and in sensory perception. The physiological relevance of NOS enzymes in the same organs was suggested by thermal stress experiments demonstrating that the constitutive expression of ShNOS is modulated in a time- and organ-dependent manner in response to environmental stressors.  相似文献   
79.
80.
Precision Agriculture - In this work, basil plants were fertilized with 0, 2.5&nbsp;mM and 10&nbsp;mM nitrogen (with different NO3?/NH4+ ratios), and then monitored using a low-power...  相似文献   
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