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21.
The effects of protein quality, protein content, ingredients, and baking process of flour blends on hearth loaves were studied. The flour blends varied in protein composition and content. Flours of strong protein quality produced hearth loaves with larger loaf volume, larger bread slice area, and higher form ratio (height/width) than flours of weak protein quality. The effect of protein content on hearth loaf depended on the size distribution of the proteins. Increasing protein content was associated with increased percentage of the largest glutenin polymers, and loaf volume and slice area increased significantly. The form ratio, however, remained unchanged with increasing flour protein content. Strong protein quality flours tolerated addition of whole meal flour better than weak protein quality flours. Increased amount of flour with strong protein quality improved hearth bread characteristics to a larger extent than increased protein content. Diacetyl tartaric acid ester of monoglycerides (DATEM) improved hearth bread characteristics, but the effect was small compared with the effect of protein composition.  相似文献   
22.

Background

Peripheral nerve sheath tumors (PNSTs) are frequently found in Danish cattle at slaughter. Bovine PNSTs share several gross and histopathological characteristics with the PNSTs in humans with heritable neurofibromatosis syndromes. The aim of the present study was to investigate a possible hereditary disposition to PNSTs in dairy cattle by statistical analysis performed on data from 567 cattle with PNSTs. Furthermore, a preliminary genome-wide association study (GWAS) was performed on DNA isolated from 28 affected and 28 non-affected Holstein cows to identify loci in the bovine genome involved in the development of PNSTs.

Results

PNSTs were significantly more common in the Danish Holstein breed than in other breeds with 0.49% of Danish Holsteins slaughtered during an eight-year-period having PNSTs. PNSTs also occurred significantly more frequently in the offspring of some specific Holstein sires. Examination of three generation pedigrees showed that these sires were genetically related through a widely used US Holstein sire. The PNSTs included in GWAS were histologically classified as neurofibroma-schwannoma (43%), schwannoma (36%) and neurofibroma (21%) and derived from Holstein cows with multiple PNSTs. A single SNP on chromosome 27 reached genome-wide significance.

Conclusions

Gross and histological characteristics of bovine PNSTs are comparable to PNSTs in humans (schwannomatosis). Danish Holsteins are genetically disposed to develop PNSTs but the examined materials are insufficient to allow determination of the mode of inheritance.  相似文献   
23.

Background

Health, productivity and antimicrobial use in the production of pigs are expected to be interrelated to some extent. Previous studies on register-based data have investigated these correlations with a subsequent large variation residing at the farm level. In order to study such farm factors in more detail we designed an elaborate interview-guide. By in-depth interviews of farmers with well-managed 7–30 kg (weaner) productions we sought to describe a set of common key-factors characterizing their management practices. Identification of such common practices could be used in follow-up projects, investigating whether identified factors really are characteristic for good-practicing famers.

Results

Eleven farms were selected for a farm visit and in-depth interview. Participating farms used less antimicrobials than the national median (8.2 animal daily doses/100 weaners/day), had a mortality below the national average (2.9%) and an average daily weight gain above the national average (443 g/day). Similarities were observed among participating farms, including the sectioning of farms, use of all-in-all-out procedures with subsequent cleaning, purchasing 7 kg weaners from only one source, as well as active participation in management by a committed farm owner. Most farmers had a specific point of focus in their management, and were convinced that this was the reason for their success. This included; feeding, treatment strategy, refurbishment of facilities and presence in the shed.

Conclusion

According to register data, participating farms were alike; in the good league regarding use of antimicrobials, mortality and daily growth. However, on-farm interviews elucidated more heterogeneity among farmers than expected. Most of the farmers had a specific point of focus, which they considered to be crucial for their good results. These results indicate the importance of non-registerable factors, highlighting the value of qualitative study techniques in the understanding of human actions. Further studies on the effect of various farmer types are recommended.  相似文献   
24.
To the 11th leaf the influence of two planting systems on yield and fruit size of apple cultivars ‘Golden Delicious, Weinsberg’ and ‘Jonagold, Rubinstar’ grafted on the dwarfed rootstocks M 9 and P 16 was investigated. The planting systems “Slender Spindle” (3.25 × 1.25 m) and “Güttinger-V-System” (3.50 × 0.60 m) were compared. In average of both cultivars and rootstocks the “Güttinger-V-System” let to significantly higher yields than the planting system “Slender Spindle”. The difference between the planting systems amounted to 121.7 t/ha from the 3rd to the 11th leaf. In this period the annual per-hectare yield of the “Güttinger-V-System” was in average 13.5 t higher than the yield of the “Slender Spindle”. The simple fruit weight of the 3rd to the 11th leaf was affected by the planting system. For both rootstocks and cultivars the simple fruit weight of the “Slender Spindle” was significantly higher than that of the “Güttinger-V-System”. However the fruit size sorting showed for both cultivars no mentioning differences between the planting systems. To the additional yield of the “Güttinger-V-System” face additional costs for the installation of the orchard and for the formation of crown. Thus the decision for this planting system will be influenced in a high measure from the producer price.  相似文献   
25.
Enhanced blood glucose levels are a hallmark of diabetes and are associated with diabetic complications and a reduction of lifespan. In order to search for plant extracts that display preventive activities in such a scenario, we tested 16 extracts used in human nutrition for their survival enhancing activities in the nematode Caenorhabditis elegans. Nematodes were exposed for 48 h to 10 mM glucose in the absence or presence of 0.1 % extract. Thereafter, survival was measured at 37 °C. Extracts made from coffee, kola, rooibos and cinnamon, did not influence the glucose-induced reduction of survival. Those made from ginseng, camomile, lime blossom, paraguay tea, balm, rhodiola, black tea, or knotgrass all extended the lifespan of the glucose-treated nematodes significantly but did not rescue survival completely. Extracts from the leaves of blackberries, from hibiscus, elderberries, or jiaogulan completely countered the glucose-induced survival reduction. A potent activation of the proteasome was shown for the most preventive extracts suggesting a more efficient degradation of proteins impaired by glucose. In conclusion, we present a simple animal model to screen for plant extracts with potency to reverse glucose toxicity. Extracts from blackberry leaves, hibiscus, elderberries, and jiaogulan were identified as very potent in this regard whose exact mechanisms of action appear worthwile to investigate at the molecular level.  相似文献   
26.
In a previous study, Giardia infection patterns were studied in newborn dairy calves over a 4-month period. Chronic Giardia infections were observed in all calves with initial cyst excretion occurring at approximately 1 month of age. In the work presented here, the passive immunity and serological immune response associated with these Giardia infections were examined. Colostrum and milk samples were collected from the dams of these calves, and monthly serum samples were collected from each calf. The colostrum, milk and sera samples were analyzed by ELISA and Western blot for the presence of anti-Giardia IgG antibodies. In addition, the in vitro anti-Giardia activity of milk and colostrum was examined using a miniculture adherence assay. When examined by ELISA, mean anti-Giardia antibody titres were found to be significantly higher in colostrum compared to milk. The monthly mean serum antibody titres in the calves were not found to differ significantly at any time point during the study. Western blot analysis revealed that colostrum from the dams reacted strongly with many different Giardia antigens between 205 and 7.5kDa, while milk reacted with few antigens in the same size range. Sera collected from the calves when 30 and 60 days of age reacted with few Giardia antigens, but as the calves aged, IgG antibodies in their sera began to react with antigens of 21, 50, 65, 73 and 79kDa. The miniculture adherence assay demonstrated that colostrum had significantly more anti-Giardia activity in vitro compared to milk. These results suggest that the calves in this dairy did not mount a significant humoral immune response against Giardia following infection. However, colostrum contained a high level of anti-Giardia antibodies and exhibited anti-Giardia activity in vitro. Therefore, colostrum may have the potential to provide initial protection against Giardia infections in calves, but the lack of a strong, specific humoral immune response by these calves could account for the high prevalence and chronic duration of the infections.  相似文献   
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29.
The pigmentation and corresponding in vivo and in vitro absorption characteristics in three different deep-water coral species: white and orange Lophelia pertusa, Paragorgia arborea and Primnoa resedaeformis, collected from the Trondheimsfjord are described. Pigments were isolated and characterized by High-Performance Liquid Chromatography (HPLC) analysis and High-Performance Liquid Chromatography Time-Of-Flight Mass Spectrometer (LC-TOF MS). The main carotenoids identified for all three coral species were astaxanthin and a canthaxanthin-like carotenoid. Soft tissue and skeleton of orange L. pertusa contained 2 times more astaxanthin g(-1) wet weight compared to white L. pertusa. White and orange L. pertusa were characterized with in vivo absorbance peaks at 409 and 473 nm, respectively. In vivo absorbance maxima for P. arborea and P. resedaeformis was typically at 475 nm. The shapes of the absorbance spectra (400-700 nm) were species-specific, indicated by in vivo, in vitro and the corresponding difference spectra. The results may provide important chemotaxonomic information for pigment when bonded to their proteins in vivo, bio-prospecting, and for in situ identification, mapping and monitoring of corals.  相似文献   
30.
Carbon isotope discrimination (?) has been proposed as selection criterion for grain yield under dry conditions, and ash content (ma) and mineral concentration were suggested as surrogates for ?. In this study, the relationship between grain yield, ?, ma and mineral concentration (Si, Ca, K, Mg) was examined in 2011 and 2012 on 16 winter rye genotypes grown under severe drought, mild drought (2012 only) and well‐watered conditions. Analyses were performed on mature flag leaves and grains. Highly significant differences between water regimes occurred for all measured traits. ?, ma and mineral concentrations were significantly correlated with grain yield under severe drought in 2011, but not in 2012 except for ? in flag leaf. ? was related to ma and mineral concentrations. Although the correlations were quite inconsistent, the results indicate that the measured traits can potentially be used as selection criterion for drought tolerance in rye. For a final statement about the suitability of these traits in rye breeding, the results should be secured with a larger and more diverse set of genotypes.  相似文献   
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