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61.
The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State.  相似文献   
62.
The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT.  相似文献   
63.
Improvements in sow productivity have raised questions regarding dietary vitamin D recommendations. The present study aimed to evaluate the effects of the housing system with access to sunlight exposure and supplementation of 25-hydroxicholecalciferol on performance and serum levels of 25(OH)D3 in sows during gestation and lactation. Sows were distributed in an experimental design with two housing systems: gestation crates or gestation free-range system with external area for sunlight exposure; and two diets: 0 or 50 μg of 25-hydroxicholecalciferol kg−1. The use of 25-hydroxicholecalciferol tended (P = 0.052) to improve total born and influenced (P = 0.046) on number of born alive. Litter weight at birth was also increased (P = 0.01) by 25-hydroxicholecalciferol supplementation; 25-hydroxicholecalciferol supplementation and housing system (free-range with sunlight exposure) tended to increase weaning weight (P = 0.07) and litter daily gain (P = 0.051) during lactation. Exposure to sunlight and 25-hydroxicholecalciferol supplementation increased 25(OH)D3 serum levels when compared with control treatment during gestation (136.95 vs. 113.92 ng mL−1; P = 0.035) and lactation (120.29 vs. 88.93 ng mL−1; P = 0.026). In conclusion, the association of 25-hydroxicholecalciferol supplementation with exposure to sunlight during gestation improved significantly 25(OH)D3 serum levels and consequently performance traits in gestation and lactation.  相似文献   
64.
The objective of this study was to evaluate neutrophil oxidative metabolism and haemogram in sheep experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E. Twenty male Corriedale sheep were utilised and distributed into four experimental groups each with five animals infected with larvae: G1‐ supplemented with sodium selenite, 0.2 mg/kg body weight (bw) given intramuscularly (IM); G2‐ supplemented with sodium selenite and vitamin E, 0.2 mg/kg bw and 2000 IU per animal, respectively, both IM; G3‐ supplemented with vitamin E, 2000 IU per animal IM; G4‐ not supplemented. A haemogram and the number of parasite eggs were determined in samples of blood and faeces, respectively, on days zero (T0), 20 (T1), 40 (T2) and 60 (T3) and nitroblue tetrazolium (NBT) assays were performed on heparinized blood samples taken on days zero, 30 and 60. A lower total leucocyte count was detected in G1 in relation to G4 at T4. Lymphocytes were reduced in G1 in relation to G3 and G4 at T3. In both non‐stimulated (NBT‐NS) and stimulated (NBT‐S) dye reduction assays, there was reduced activity at 60 days, in relation to other times in the groups treated with selenium (G1 and G2). On the basis of results obtained, we conclude that supplementation with selenium provides better antioxidant protection to neutrophils.  相似文献   
65.
Physicochemical properties of maize starch obtained under different steeping conditions by intermittent milling and dynamic steeping process (IMDS) were studied. Brazilian dent maize (hybrid XL 606) was milled using a 2×2×3 factorial experimental design with two lactic acid levels (0.0 and 0.55%, v/v), two SO2 levels (0.05 and 0.1%, w/v), and three temperatures (52, 60, and 68°C). Properties of starch obtained by conventional wet‐milling process (36 hr at 52°C, 0.55% lactic acid, and 0.2% SO2) were used for comparison. Starch protein content and solubility increased with presence of lactic acid, while swelling power decreased. Higher SO2 concentration (0.1%) had the same effect as lactic acid on some properties. Steeping temperatures of 60 and 68°C increased solubility and most of the thermal properties but reduced swelling power, suggesting stronger starch annealing during IMDS at these temperatures. Some thermal changes on starch granules were visualized by scanning electron microscopy (SEM) at 60 and 68°C. Amylose content as well as pasting properties were affected by steeping factors and interactions. Starches from IMDS and conventional wet‐milling processes were similar in most properties, indicating that IMDS provides starch with quality similar to that from conventional milling.  相似文献   
66.
Experimental studies and the analysis of published data have shown that carbon reserves in soils generally increase upon soil exclusion from agricultural use. The rate of carbon accumulation in the abandoned soils depends on the soil type, the time elapsed since the soil abandoning (the restoration period), and the thickness of the layer for which the rate of carbon accumulation is determined. For the upper 20-cm-thick layer, it varies from 66 to 175 g C/m2 per year in dependence on the type of soil and averages 111 g C/m2 per year. The highest rate is typical of the first 10–15 years of soil restoration. According to our calculations, the carbon sequestration in the upper 20-cm-thick layer of Russian soils due to changes in land use was 184–673 Mt C in 1990–2005 and may reach 282–1030 Mt C by 2020.  相似文献   
67.
This study examined the effects of O2 concentration (5% vs 20%) during in vitro maturation (IVM), fertilization (IVF) and culture (IVC) or supplementation of IVM and IVC media with cysteamine (50 and 100 μm , respectively; IVM, IVF and IVC carried out in 20% O2), on blastocyst rate and relative mRNA abundance of some apoptosis‐related genes measured by real‐time qPCR in immature and in vitro‐matured buffalo oocytes and in embryos at 2‐, 4‐, 8‐ to 16‐cell, morula and blastocyst stages. The blastocyst rate was significantly higher (p < 0.05) while the percentage of TUNEL‐positive cells was significantly lower (p < 0.05) under 5% O2 than that under 20% O2. The mRNA expression of anti‐apoptotic genes BCL‐2 and MCL‐1 was significantly higher (p < 0.05) and that of pro‐apoptotic genes BAX and BID was lower (p < 0.05) under 5% O2 than that under 20% O2 concentration at many embryonic stages. Following cysteamine supplementation, the blastocyst rate and the relative mRNA abundance of BCL‐XL and MCL‐1 was significantly higher (p < 0.05) and that of BAX but not BID was lower (p < 0.05) at many stages of embryonic development, although it did not affect the percentage of TUNEL positive cells in the blastocysts significantly. The mRNA expression pattern of these genes during embryonic development was different in 5% vs 20% O2 groups and in cysteamine supplemented vs controls. At the 8‐ to 16‐cell stage, where developmental block occurs in buffalo, the relative mRNA abundance of BCL‐2 and MCL‐1 was highest under 5% O2 concentration and that of BAX and BID was highest (p < 0.05) under 20% O2 concentration. These results suggest that one of the mechanisms through which beneficial effects of low O2 concentration and cysteamine supplementation are mediated during in vitro embryo production is through an increase in the expression of anti‐apoptotic and a decrease in the expression of pro‐apoptotic genes.  相似文献   
68.
This study evaluated the influence of calcium and magnesium ions on the empirical rheological properties of wheat flour to verify possible effects of these ions on processing because, in addition to their nutritional importance, they are also responsible for water hardness. Calcium (0–1.30 g/100 g) and magnesium (0–0.34 g/100 g) ions from sulfate salts were added to wheat flour, according to a central composite rotatable design. The farinograph and extensigraph properties of wheat flour and its mixtures were evaluated. The results were analyzed by response surface methodology. Calcium ions stood out for increasing water absorption, decreasing mixing stability, and producing a delayed effect on dough extensibility (reduced at 135 min). Magnesium ions influenced most flour rheological properties in a similar manner to oxidizing agents (increased dough stability, increased resistance to extension, and reduced extensibility), thus proving to be a possible replacement agent for these additives. An interaction effect of the combined calcium and magnesium ions was observed on dough development time. The results showed that effects on processing can occur when wheat flour fortification is made, and adaptations on wheat flour specifications, product formulation, and processing parameters may be required.  相似文献   
69.
Intensive fish farming has resulted in an increased concern for disease outbreaks. Probiotic use is one of the strategies being developed to improve fish health and productivity. Measures of probiotic colonization, growth performance, haematological characteristics and parasite load were used to evaluate the effect of diets supplemented with Enterococcus faecium on growth and health of Arapaima gigas juveniles. A completely randomized design with four treatments (diet with E. faecium at 1 × 106 CFU/g and 1 × 108 CFU/g, control diet and diet with the culture medium MRS) and three replicates was used. Ninety‐six Arapaima juveniles were distributed in 12 cages fed with the specified diet for 68 days. Colonization of the intestinal tract by lactic acid bacteria reduced the total number of heterotrophic bacteria in fish fed with probiotics compared to controls. Fish fed a supplemented diet containing 1 × 108 CFU/g presented higher values of weight gain, survival and fish growth uniformity, and lower values of feed conversion ratio. The prevalence of Trichodina sp. could have affected the survival of fish in the control group. Reduction in parasite load and an increase in haematocrit, the number of erythrocytes, thrombocytes, neutrophils and monocytes were also observed in fish fed the diet containing 1 × 108 CFU/g. Enterococcus faecium presented a probiotic effect in A. gigas juveniles and can be recommended for use at a concentration of 1 × 108 CFU/g to modify the gut microbiota, improve growth performance and haematology and reduce parasitic load.  相似文献   
70.
We aimed to estimate transgenerational epigenetic variance for body weight using genealogical and phenotypic information in meat quails. Animals were individually weighted from 1 week after hatching, with weight records at 7, 14, 21, 28, 35 and 42 days of age (BW7, BW14, BW21, BW28, BW35 and BW42, respectively). Single‐trait genetic analyses were performed using mixed models with random epigenetic effects. Variance components were estimated by the restricted maximum likelihood method. A grid search for values of autorecursive parameter (λ) ranging from 0 to 0.5 was used in the variance component estimation. This parameter is directly related to the reset coefficient (ν) and the epigenetic coefficient of transmissibility (1‐ν). The epigenetic effect was only significant for BW7. Direct heritability estimates for body weight ranged in magnitude (from 0.15 to 0.26), with the highest estimate for BW7. Epigenetic heritability was 0.10 for BW7, and close to zero for the other body weights. The inclusion of the epigenetic effect in the model helped to explain the residual and non‐Mendelian variability of initial body weight in meat quails.  相似文献   
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