Are forests potential landscape barriers for foraging bumblebees? Landscape scale experiments with Bombus terrestris agg. and Bombus pascuorum (Hymenoptera, Apidae)     

Daria Kreyer  Kerstin Walther-Hellwig 《Biological conservation》2004,116(1):111-118

Habitat fragmentation is generally considered to have detrimental effects on insect movement and associated pollen flow between plant populations. Against this background the role of forests as potential barriers for foraging bumblebees of the species Bombus terrestris agg. and Bombus pascuorum was studied in different experiments. Bombus terrestris agg. workers were found foraging at distances of up to 2.2 km from their nests. B. terrestris agg. as well as B. pascuorum individuals crossed 600 m of forestland between floral mass resources (Phacelia tanacetifolia, Helianthus annuus), although in general a high degree of site fidelity was observed. B. pascuorum workers accepted artificial floral resources within the forest, whereas the minor use of resources below forest canopy observed for B. terrestris agg. possibly indicates a preference for direct forage flights, probably leading above the forest canopy. Our results warn against experiments with genetically modified crop species with potential bumblebee pollination (e.g. Brassica napus), in which an isolating effect of forests is assumed.  相似文献   

The Application of Multivariate Statistical Methods for the Evaluation of Soil Profiles (8 pp)     

Kerstin Sielaff  Jürgen W. Einax 《Journal of Soils and Sediments》2007,7(1):45-52

Background, Aim and Scope   Contamination of soils does not only occur on their surface over large areas, but also in depth. Therefore a characterization of soil state after pollution demands a three-dimensional soil sampling, by what a large number of samples has to be analyzed. Analytical results could be evaluated by multivariate statistical methods, which have already been used for the evaluation of data sets containing results from soil sampling of two dimensions like areas or single profiles. In this case study, multivariate statistical methods were applied to investigate structure and interactions between features in a data set containing results of three-dimensional soil sampling. The investigated soil profiles were contaminated by emissions of a former cement and phosphate fertilizer plant. The aim of this study was to determine the remaining extent of contamination and to analyze whether pollutants are mobilized and vertically transported within the profiles. Materials and Methods: Three soil profiles were sampled in the surroundings of the plant. Grain size, organic and carbonatic bonded carbon, pH value, and the total contents of Ca, Cd, Co, Cu, F, Fe, K, Mn, Mg, Na, Ni, P, Pb, and Zn were determined. The resulting data set was evaluated by cluster analysis, linear discriminant analysis, and principal components analysis. The sequential extraction procedure according to Zeien and Brümmer was applied to analyze the binding properties of Ca, Cd, Cu, Na, Pb, and Zn from selected samples. Results: Cd was identified as contaminant of the top soils. The pH values of the bottom soils were determined to be in alkaline range, which is unnaturally high. Variables were clustered according to enrichment of variables in top soils. The samples were classified regarding their pollution state and their substrate by cluster analysis, which was confirmed by linear discriminant analysis. Geogenic and anthropogenic sources of variables as well as relationships between variables like the binding of heavy metals at organic matter were detected by using principal components analysis. The binding of heavy metals at organic matter in the top soils was confirmed by the results of the applied sequential extraction. A vertically altered distribution of Na binding was determined. Discussion: According to the current soil conditions, the uptake of heavy metals had probably occurred by the over ground part of plants during the deposition. The distribution of Na should likely result from the vertical transport of Na, which would also explain the high pH values of the bottom soils by ion exchange. Altogether, the main amount of deposited Ca, F, Na, P, and heavy metals is likely nearly insoluble bound in the top soils. Conclusions: Ten years after the end of production, the pollution of top soils in the surroundings of the former plant is still high. However, regarding the ecotoxicological relevance the now explored interactions between several soil features and elements strongly indicate that there is no short-term to medium-term risk of a mobilization of the deposited elements with the exception of Na. Recommendations and Perspectives: The results of this case study prove that multivariate statistical methods are powerful tools to explore interactions of variables and relationships in a data set derived from three dimensional soil sampling. The methods applied in this work can be highly recommended for evaluations of large data sets resulting from two- or three-dimensional samplings. Multivariate statistical methods enable the characterization of soils and their pollution state in a simple and economic way.  相似文献   

Consumer reactions to boar meat - A reviewRéactions des consommateurs à la viande de porcs mâles entiers-une revueVerbraucherreaktionen auf Eberfleisch — ein Übersichtsreferat     

Birgitta Malmfors  Kerstin Lundström 《Livestock Production Science》1983,10(2):187-196

Over the last ten years, consumer reactions to boar meat have been studied in nine experiments performed in six European countries. In these different studies, conditions have differed with regard to experimental design, proportions of tainted boars and products tested. The proportions of consumers judging the odour of the tested boar meat to be less pleasant than that of normal pig meat has mainly varied from about 5 to 35%. This should be compared with 3–10% for meat tested from gilts and castrates. The results differ between countries and also between products. The most favourable results have been obtained for cured bacon, cooked ham and sausage. The conclusion must be drawn that most boar meat would be accepted by consumers. Further research should be directed to finding a reliable screening test for sorting out tainted boar carcasses.  相似文献   

Physiological experiments on bolting of sugar beet     

Lexander  Kerstin 《Plant foods for human nutrition (Dordrecht, Netherlands)》1966,13(1-4):368-374

Plant Foods for Human Nutrition -  相似文献   

Analysis of relationships between German heavy horse breeds based on pedigree information     

Aberle K  Wrede J  Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(1-2):72-75

We analysed the relationship coefficients (R) between the four German heavy horse breeds South German Coldblood, Rhenish German Draught Horse, Schleswig Draught Horse and Black Forest Draught Horse. The relationship coefficient makes it possible to ascertain crossbreeding between the breeds over time, or autonomous developments of the breeds, respectively. The investigation revealed that the relationship coefficients between the German draught horse breeds were very low. The mean relationship coefficients between the four German heavy horse breeds were largest between the South German Coldblood and Schleswig Draught Horse (0.103%), whereas mean relationship coefficients were lowest between the Rhenish German and Black Forest Draught Horse (0.001%). The Rhenish German Draught Horse showed largest relationship coefficients with the Schleswig Draught Horse (0.09%), while the Black Forest Draught Horse was mostly related to the South German Coldblood (0.06%). The results reveal the presence of very few common progenitors of the breeds. The gene flow between the breeds is primarily due to crossbreeding of stallions and, especially, in the Rhenish German Draught Horse population breeding with a few mares from other German draught horse breeds.  相似文献   

The effects of a single injection of dexamethasone-21-isonicotinate on the lymphocyte functions of dairy cows at two weeks post partum     

Thanasak J  Jorritsma R  Hoek A  Noordhuizen JP  Rutten VP  Müller KE 《Veterinary research》2004,35(1):103-112

Dexamethasone is a potent therapeutic for treatment of the fatty liver syndrome or primary ketosis in post partum dairy cows. Reservations exist, however, among practitioners with respect to the risk of immunosuppression induced by corticosteroids. The aim of this study was to investigate the effect of a single injection of dexamethasone-21-isonicotinate on distinct immune functions of postpartum dairy cows because only scarce information is available on the effects of corticosteroid preparations when administered at a dosage and frequency for treatment of the fatty liver syndrome or primary ketosis. Sixteen Swedish red-pied dairy cows, between days 9 and 15 post partum, were allotted to either a control group (n = 8) or a treatment group (n = 8). The cows in the treatment group received a single intramuscular injection of a dexamethasone-21-isonicotinate suspension at a dosage of 0.02 mg/kg i.m. at the start of the experiment. White blood cell counts and selected lymphocyte functions (lymphocyte proliferation, expression of lymphocyte markers and the b2 and a4 chain of adhesion molecules belonging to the integrin family) and some parameters of the energy metabolism (glucose, insulin) were determined before the administration of corticosteroids (day 0) and subsequently at days 2, 4, 7 and 9 of the experiment. Changes in glucose and insulin were within the target range for treatment of the fatty liver syndrome or primary ketosis. Significant (P < 0.05) increases in the number of circulating white blood cells were observed in treated cows on the second day following treatment which was exclusively caused by an increase in the number of circulating neutrophils. Lymphocyte blastogenesis in response to ConA and the percentages of lymphocytes positive for CD2, CD4, CD8, CD49d and CD18 as well as the intensity of CD49d expression did not differ between the treatment and control groups. There was, however, a significant reduction (P < 0.01) in the intensity of CD18 expression on lymphocytes in the treated animals on the fourth day after treatment. In conclusion, a single administration of dexamethasone-21-isonicotinate in a dosage of 0.02 mg/kg i.m. at two weeks post partum in healthy cows had a significant but highly transient effect on CD18 expression on lymphocytes and the number of peripheral blood neutrophils, but did not affect lymphocyte blastogenesis or lymphocyte subpopulation patterns in peripheral blood.  相似文献   

Prolonged remission after immunosuppressive therapy in six dogs with pemphigus foliaceus     

Olivry T  Bergvall KE  Atlee BA 《Veterinary dermatology》2004,15(4):245-252

Limited information is available on the long-term outcome of treatment of pemphigus foliaceus in dogs. The purpose of this study is to report that a prolonged remission can occur after discontinuation of immunosuppressive regimens in some animals with this disease. Six dogs were diagnosed with pemphigus foliaceus based on suggestive clinical signs and histopathology. These patients were treated either with immunosuppressive doses of oral glucocorticoids or with a combination of oral glucocorticoids and azathioprine. After clinical signs underwent complete remission, which occurred 1.5-5 months after immunosuppression was initiated, the drugs were tapered progressively and eventually withdrawn. The total duration of immunosuppressive therapy varied between 3 and 22 months. Skin lesions of pemphigus foliaceus did not recur for 1.5-6 years after treatment was stopped. These observations suggest that, in some dogs with pemphigus foliaceus, immunosuppression can lead to long-term remission of skin lesions, and that discontinuation of treatment is not necessarily followed by a recurrence of clinical signs.  相似文献   

Effect of different hand-milking techniques on milk production and teat treatment in Zebu dairy cattle     

Millogo V  Norell L  Ouédraogo GA  Svennersten-Sjaunja K  Agenäs S 《Tropical animal health and production》2012,44(5):1017-1025

The aim of the study was to test three different hand-milking techniques (“pull down”, “thumb in”, and “full hand grip”) and their effects on milk production and teat treatment. This is important since milk production in many tropical areas still rely on hand-milking. The study was carried out at a peri-urban farm in the Bobo-Dioulasso area in Burkina Faso. Twelve indigenous Zebu cows in early lactation were used in the study. The sequences of the treatments (hand-milking techniques) and the milkers were balanced for carry-over effects between successive periods and days, respectively. The sequences were constructed by using special Latin squares. Yield and composition of saleable milk was not affected by milking technique but there were differences between the milkers in milk yield. There was also a significant interaction for saleable milk yield between milker and milking technique. Hemoglobin in milk was measured as an indicator of teat damage. The hemoglobin content was numerically higher in post-milking strip milk samples than in saleable milk. It was concluded that the amount of milk removed depends mainly on the milker and how well the milking technique works for the individual milker. No effect of milking technique was observed on teat treatment.  相似文献   

A review of topical therapy for skin infections with bacteria and yeast     

Mueller RS  Bergvall K  Bensignor E  Bond R 《Veterinary dermatology》2012,23(4):330-41, e62

Background – Cutaneous infections with bacteria and yeasts are common in small animal practice. Treatment with systemic antibiotics or antifungal agents may not be ideal, because of the increasing development of multiresistant organisms, the cost and the possible adverse effects. Topical antimicrobials may be used as adjunctive therapy to systemic treatment or as sole therapy instead of systemic treatment. Objective – This literature review evaluated studies on topical antimicrobial treatment of skin infections. Methods – In vitro and in vivo studies evaluating topical antimicrobial agents were identified using a number of electronic and manual searches of textbooks and articles. Studies were evaluated, and the evidence for or against the use of the topical agents was extracted. Results – There is good evidence for the efficacy of chlorhexidine and, to a lesser degree, benzoyl peroxide in canine bacterial skin infections. There is limited evidence for the efficacy of silver sulfadiazine and medical honey against bacterial skin infections in the dog, and for the efficacy of hydrogen peroxide and stannous fluoride in the horse. Good evidence supports the use of a combination of chlorhexidine and miconazole in dogs with cutaneous Malassezia infections. There is insufficient evidence to recommend any other topical therapy for use in cutaneous infections. Conclusions and clinical importance – Although many antimicrobial topicals are marketed in veterinary dermatology, the efficacy has been reported for only a minority of agents. Randomized controlled trials evaluating various topical treatments are therefore urgently needed.  相似文献   

Establishment of diagnostic criteria for feline nonflea-induced hypersensitivity dermatitis     

Favrot C  Steffan J  Seewald W  Hobi S  Linek M  Marignac G  Olivry T  Beco L  Nett C  Fontaine J  Roosje P  Bergvall K  Belova S  Koebrich S  Pin D  Kovalik M  Meury S  Wilhelm S 《Veterinary dermatology》2012,23(1):45-50, e11

Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD.  相似文献