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61.
Hijazin M Ulbegi-Mohyla H Alber J Lämmler C Hassan AA Timke M Kostrzewa M Prenger-Berninghoff E Weiss R Zschöck M 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(1-2):32-37
In the present study A. (T.) abortisuis isolated from pigs and bovines could be reliably identified by determination of phenotypic properties, genotypically by polymerase chain reaction with the help of A. (T.) abortisuis 16s-23S rDNA intergenic spacer region specific oligonucleotide primer and by Matrix-Assisted Laser Desorption Ionization-Time Of Flight mass spectrometry (MALDI-TOF MS). The latter appeared to be a promising tool for fast and cost effective identification of this species and might help to elucidate the role A. (T.) abortisuis plays in infections of pigs, bovines, possibly other animals or humans. 相似文献
62.
Haufe HC Gygax L Wechsler B Stauffacher M Friedli K 《Preventive veterinary medicine》2012,105(1-2):85-92
In this study, the effects on the claw health of dairy cows of three different floor types and access to pasture were investigated on 35 farms. The farms were fitted with a given floor type in the indoor walking area of a cubicle housing system: a solid rubber, mastic asphalt or slatted concrete floor. Because we chose farms on which the given floor type was in good condition, the data presented show what can be achieved on these types of floors under ideal circumstances. Cows on half of the farms per floor type had access to pasture during the grazing period. Each farm was visited three times at approx. 6-month intervals at the end of the winter indoor-housing period and at the end of the summer period, i.e. after the period with access to pasture on half of the farms. During each visit, the claw health of the same 10 cows per farm was assessed on the occasion of routine claw trimming. The proportion of cows with haemorrhages increased from mastic asphalt to rubber and slatted concrete floors. A lower proportion of cows kept on mastic asphalt was affected by white-line fissures and needed intermittent claw-trimming, an indicator for lameness. Cows housed in cubicle systems with slatted concrete floors were at the lowest risk of having heel-horn erosions. Access to pasture was associated with a lower incidence of slight white-line fissures and dermatitis digitalis. A higher proportion of cows with sole haemorrhages and sole ulcers were found on all floor types at the end of the summer period than at the end of the winter indoor-housing period. Floor type did not influence the presence of sole ulcers and deep white-line fissures. In conclusion, the effect of floor type on claw health was slight, and none of the investigated floor types was clearly superior to the others. Access to pasture was not effective in reducing the presence of most types of claw lesions associated with the floor type used in the indoor walking area. 相似文献
63.
Markus Euring Jerzy Trojanowski Marina Horstmann Alireza Kharazipour 《Wood Science and Technology》2012,46(4):699-708
In this work, the results of the enzymatic oxidation of TMP-fibers (thermomechanical pulp) and a well-structured lignin model compound, the dehydropolymer (DHP), were investigated by different 14C and 13C methods, caused by a Laccase–Mediator-System (LMS). These methods are the nuclear magnetic resonance spectroscopy (13C-NMR) with DHP (unmarked) and the determination of the 14CO2 release of 14C-marked DHP and TMP-fibers. The 13C-NMR measurements were chosen to analyze the structural changes of the LMS-treated DHP model compounds and TMP-fibers qualitatively and quantitatively. The data of 14CO2 release give an explanation of the demethylation of DHP and TMP-fibers. The effect of the LMS is shown by comparing the results in respect of DHP and TMP-fibers, which were only treated with laccase and of an inactivated LMS as the control. Comparing the results of the 13C-NMR method, in particular the use of the Mediator during the enzymatical treatment, showed significant changes in the structure of the DHP. Also, the TMP-fibers were materially influenced by the LMS. The analysis of the 14CO2 release data of the 14C-marked DHP and TMP-fibers revealed that the rate of 14CO2 increases in the 14C-2 atom as well as in the O14CH3 group within the first hour of Laccase–Mediator incubation. Therefore, the 14CO2 release from the DHP was higher than from the TMP-fibers. 相似文献
64.
Aberra Melesse H. Steingass J. Boguhn M. Schollenberger M. Rodehutscord 《Agroforestry Systems》2012,85(3):505-518
The baobab tree (Adansonia digitata L.) is of large socioeconomic importance. However, domesticated plant material of baobab is rarely available to African farmers, and very limited pre-breeding knowledge is available. To evaluate genetic differentiation between geographical origins we compared vigor and leaf morphology of trees from 17 West African and 13 East African provenances of baobab. Seedlings were grown and evaluated in a common garden test at Bamako, Mali. Germination was assessed and growth measured 3 and 12?months after germination. Leaf morphology (leaf length, leaflet number, petiole length and diameter and leaflet border) were assessed after 12?months. Significant differences between the provenances were observed for both growth rate and leaf morphology. West African provenances in general grew faster than East African provenances, but leaf characters did not reveal a particular geographic structure, and the correlations between geographic distances and multivariate Mahalanobis distances were not significant. The correlations between leaf morphological traits and climatic data were in general low at the provenance level. However, the number of leaflets was significantly higher for provenances from drier areas. Two years increment at a field site also varied significantly between the provenances, where West African provenances confirmed their tendency to higher growth rate. Still, trees are young and results regarding both growth data and leaf characteristics should be confirmed when the trees are closer to maturity. 相似文献
65.
The landscape matrix modifies the effect of habitat fragmentation in grassland butterflies 总被引:1,自引:0,他引:1
Erik ?ckinger Karl-Olof Bergman Markus Franzén Tomá? Kadlec Jochen Krauss Mikko Kuussaari Juha P?yry Henrik G. Smith Ingolf Steffan-Dewenter Riccardo Bommarco 《Landscape Ecology》2012,27(1):121-131
The landscape matrix is suggested to influence the effect of habitat fragmentation on species richness, but the generality
of this prediction has not been tested. Here, we used data from 10 independent studies on butterfly species richness, where
the matrix surrounding grassland patches was dominated by either forest or arable land to test if matrix land use influenced
the response of species richness to patch area and connectivity. To account for the possibility that some of the observed
species use the matrix as their main or complementary habitat, we analysed the effects on total species richness and on the
richness of grassland specialist and non-specialist (generalists and specialists on other habitat types) butterflies separately.
Specialists and non-specialists were defined separately for each dataset. Total species richness and the richness of grassland
specialist butterflies were positively related to patch area and forest cover in the matrix, and negatively to patch isolation.
The strength of the species-area relationship was modified by matrix land use and had a slope that decreased with increasing
forest cover in the matrix. Potential mechanisms for the weaker effect of grassland fragmentation in forest-dominated landscapes
are (1) that the forest matrix is more heterogeneous and contains more resources, (2) that small grassland patches in a matrix
dominated by arable land suffer more from negative edge effects or (3) that the arable matrix constitutes a stronger barrier
to dispersal between populations. Regardless of the mechanisms, our results show that there are general effects of matrix
land use across landscapes and regions, and that landscape management that increases matrix quality can be a complement to
habitat restoration and re-creation in fragmented landscapes. 相似文献
66.
Hildebrand B Boguhn J Dänicke S Rodehutscord M 《Journal of animal physiology and animal nutrition》2012,96(2):307-318
In this study, the effect of Fusarium toxin-contaminated triticale (FUS) at high (60%) and low (30%) concentrate proportion in ruminant rations on ruminal fermentation, microbial protein synthesis and digestibility was investigated, using in vivo and in vitro methods. Significant effects of the forage-to-concentrate ratio on ruminal degradation and digestibility of crude nutrients and detergent fibre fractions as well as on the pH value and the concentration of short chain fatty acids (SCFA) in rumen fluid were found. The production of SCFA was affected, and the degradation of crude fibre and neutral detergent fibre in the rumen was reduced by the inclusion of FUS at high concentrate proportion. The efficiency of microbial crude protein synthesis was higher in diets with 60% than in diets with 30% concentrates, but was impaired in the presence of FUS in vitro at the high concentrate level. Marginal effects of FUS on the amino acid pattern of microbial protein were detected. It was concluded that the use of FUS in high concentrate diets can influence ruminal fermentation and microbial protein synthesis at a dietary deoxynivalenol concentration below 5 mg/kg dry matter. 相似文献
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