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51.
Journal of Plant Diseases and Protection - We identified ten current key challenges for plant protection in cities each of them belonging to a specific field of action of IPM in urban horticulture...  相似文献   
52.
Full use of residues from industrial processes is a fundamental necessity of contemporary society, since it avoids impacts to the environment by using residues as inputs for other products of high economic and social importance. In this study, lipase production of the crude enzymatic extracts obtained by Aspergillus niger using cassava peel as substrate and sunflower oil as an inductor was investigated. The optimized cultivation temperature and concentration of inductor were determined using the response surface methodology. The two variables studied exercised influence in the production of lipase in the 95% level of confidence. The response surface obtained indicated that the conditions that maximize lipase activity production were 30.5 ~C and initial concentration of sunflower oil was 2.5% (w/w). Through this analysis, it is evident that extremes in temperature and concentration of inductor tend to decrease lipase production, since low temperatures decrease metabolism and high temperatures may inactivate the lipase. Optimum lipase yield was 59.8 U/g of dry peel which was fermented for 60 h. Lipase production presents a peak of 61.3 U/g, at 72 h of fermentation. However, this value is statistically equal (p 〉 0.05) of the value of lipase activity obtained for 60 h and 84 h of fermentation.  相似文献   
53.
Black root-rot, caused by the soil-borne pathogen Thielaviopsis basicola leads to potential problems with a wide range of crops including grain legumes. During the 2007 growing season this pathogen was isolated from naturally infected narrow-leafed lupines (Lupinus angustifolius) in several areas. A first screening of disease resistance performed with a collection of L. angustifolius cultivars indicated a range from highly susceptible to moderate tolerant. In order to accelerate the screening procedure and to improve the identification of field samples a nested PCR-based detection was developed based on pathogen specific primers derived from the internal transcribed spacer regions (ITS) of T. basicola. Tests conducted on a wide range of potential lupin pathogens showed a high T. basicola specificity without any cross-reactions on other fungal pathogens. In more than 80% of the analysed field samples T. basicola-DNA was detected. For further resistance screenings the presented diagnostic test will contribute to an early and specific identification of T. basicola in plants.  相似文献   
54.
Calf losses (CL, mortality and unwanted early slaughter) in veal production are of great economic importance and an indicator of welfare. The objective of the present study was to evaluate CL and the causes of death on farms with a specific animal welfare standard (SAW) which exceeds the Swiss statutory regulations. Risk factors for CL were identified based on information about management, housing, feeding, and medication. In total, 74 production cohorts (2783 calves) of 15 farms were investigated. CL was 3.6%, the main causes of death were digestive disorders (52%), followed by respiratory diseases (28%). Factors significantly associated with an increased risk for CL were a higher number of individual daily doses of antibiotics (DDA), insufficient wind deflection in winter, and male gender. For administration of antibiotics to all calves of the cohort, a DDA of 14-21 was associated with a decreased risk for CL compared to a DDA of 7-13 days.  相似文献   
55.
Earlier studies investigating the cross-reactivity of antibodies submitted to the HLDA8 had used flow cytometry as a method of choice to screen mAbs for reactivity with equine leukocytes, including two-color flow-cytometry to characterize the lymphocyte population they detect. In addition, immuno-histochemistry (IHC) was used to detect distribution of positive cells in lymphoid tissue sections. In this study we performed immunoprecipitation (IP) to complement the previous results and add valuable information regarding the molecules detected by the cross-reacting antibodies. Surface molecules from primary equine PBMC or the equine cell line T8888 were biotinylated prior to precipitation to determine the molecular weight of the corresponding molecules in a western blot using streptavidin-AP. 21 out of 24 mAbs precipitated the molecules with a MW corresponding to its human orthologue. Positive mAbs were directed against CD2, CD5, CD11a, CD11b, CD14, CD18, CD21, CD44, CD83, CD91, CD172a, MHCI and MHCII. Three mAbs directed against CD49d, CD163, and CD206 which were unambiguously identified earlier by flow cytometry failed to immunoprecipitate the corresponding CD molecule. MAbs detecting CD molecules which are expressed internally like CD68 and mAbs of IgM class could not be included into this approach.  相似文献   
56.
57.
By the distribution of a questionnaire between all Swiss cattle practitioners it was possible to investigate abortions and other animal health problems related to Bluetongue vaccination 2009. The questionnaire helped to obtain plausibility and timely relation of the reported disorders. 58 abortions in cattle and different herd health problems could be examined. Because there is no possibility to show that a vaccination itself leads to an abortion the results of proven causes of abortions prior and after Bluetongue vaccination were compared regarding their diagnosis. Due to the fact that diagnosis and solving rate of abortions did not differ before and after vaccination, the vaccination itself cannot be responsible for the abortions. Evaluation of different herd health problems showed that Bluetongue vaccination was not responsible for these disorders which often existed already prior to vaccination. Herd health problems generally have multifactorial causes what makes it difficult to asses the effect of Bluetongue vaccination in some cases.  相似文献   
58.
To understand soil food webs, empirically generated data on the trophic connections and the feeding ecology of the major below-ground animal taxa are needed. Here we used stable isotope analysis to assess the trophic ecology of wireworms, the larvae of click beetles, in Central European arable land. Wireworms are amongst the major soil macroinvertebrates and are of practical importance in arable soils. Besides feeding on crops, they are thought to feed on weeds, soil organic matter (SOM), and even animal prey, but their feeding ecology is poorly studied under natural conditions. Elaterid larvae and their putative feeding substrates—plant roots, SOM, and litter—were sampled at 17 locations in Austria, Germany, and Italy and their isotope ratios of carbon (12C/13C) and nitrogen (14N/15N) measured to determine the wireworms’ trophic level, the importance of SOM and weeds within the diet of Agriotes larvae, as well as the individual diet variation in Agriotes obscurus larvae. δ15N signatures suggested that Agriotes larvae are predominately herbivorous, whereas the other wireworm species primarily fed on animal prey. In contrast to SOM, weeds were readily eaten by Agriotes larvae: their dietary contribution ranged between 28% and 67% in weedy maize fields. Most A. obscurus larvae fed on a mixed diet of weeds and maize, although ~15% of the larvae fed primarily on one of the two food sources only. δ15N signatures indicated that ~10% of the “herbivorous” A. obscurus larvae fed primarily on animal prey, revealing high intraspecific trophic plasticity in these soil insects. Wireworm feeding behaviour is apparently complex at the individual level: the population consists of types A and B generalists, a phenomenon which needs further assessment.  相似文献   
59.
Acid-base disorders were investigated in 50 calves with chronic indigestion and metabolic acidosis. In the calves that were unable to stand up, the acidosis was significantly more severe than in the calves that could stand up. The anion gap and four different components of the base excess were calculated by the method described by Fencl. The anion gap was high in more than half of the calves, and it was significantly associated with the base excess due to unidentified anions. However, in seven of the calves, the excess of unidentified anions would not have been detected without the calculations, which made it possible to measure the effect of sodium, chloride, plasma protein and unidentified anions on the acid-base balance. Twenty-four of the calves had a combination of hyperchloraemic and high anion gap metabolic acidosis. Changes in sodium and plasma protein concentrations had a minor impact on the calves' acid-base status.  相似文献   
60.
Contents
Investigations into the role of pheromones in reproductive behaviour have been mainly limited to the boar, with 16-unsaturated C-19 steroids playing a major role. Similarities in the mating behaviour of the camel and pig suggest that pheromones may also be important in the camel. The aim of this study was to determine the concentrations of 16-unsaturated steroids in camel testes and other tissues. Samples of testicular tissue were obtained by castration from six male camels (9–15 years) and 16-unsaturated steroid content was measured by gas–liquid chromatography (GLC). In addition, samples of the glandula occipitalis ('poll gland'), g. parotis, g. submandibularis and the palatal flap ('dulaa') were obtained from a 10-year-old camel and also analysed for steroid content. Results were confirmed by GC-MS (gas-chromatography-mass spectrometry) in selected testicular samples. 5α-androst-16-en-3-one could be detected in all testicular specimen (range 0.05–1.28  μ g/g tissue) as well as in all the other tissues analysed, with highest concentrations in the glandula occipitalis. 5α-androst-16-en-3β-ol was present in most tissues, whereas 5α-androst-16-en-3α-ol was detectable at 0.75  μ g/g only in one testes which also had the highest level of 5α-androst-16-en-3-one. The similarities of these findings to the porcine species suggest a role of 16-unsaturated steroids as pheromones in the camel. Further experimental evidence however, is required to confirm these findings.  相似文献   
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