Das Erlernen eines Anwendungszeitraumes mit Hilfe eines Signals1

It was examined if animals can learn to perform bar-pressing only within a determined period of time by the aid of light and tone signals. 6 male BDE-rats (70 days old at the beginning of the experiments) were trained in a modified test chamber to press a bar only in 2h/day (experimental subjects 1 and 2: 13.00–15.00 h; 3 and 4: 15.00–17.00 h; 5 and 6: 24.00–2.00 h). During this time light and tone signals were given and only during this time bar-pressing was rewarded. At the end of the training period all 6 rats showed a change of behavior according to the task, that means: at least 90% of the whole bar pressing activity fell into the determined period of time. Under test conditions the maintenance of this behavior was less stable.     

ELISA – Nachweis von Pflanzenviren mit Hilfe unterschiedlicher Reagenzstreifen

Abstract Detection of plant viruses by ELISA using different reagent strips
A simplified immunoassay for detection of plant viruses under field conditions was developed on the basis of the direct double antibody sandwich ELISA using dry reagent carriers immobilized on PVC-supports which are arranged in a fan-like manner. The fan consists of a first reagent carrier with antivirus IgG covalently bound to cyanuric chloride-activated (CCA) paper while the second and third are filter papers impregnated with alkaline phosphatase labelled antivirus IgG and the fluorogenic subsrate, 4-methylumbelliferylphosphate, respectively. Performing the test, the first carrier is contacted with a liquid sample containing the virus to be identified, the second and third carriers is contacted with a liquid sample containing the virus to be identified the second and third carriers are sequentially put one upon the other and the reactions carried out. The virus is detected by the reacted substrate fluorescing under a UV-light. The applicability of the test is demonstrated with cucumber mosaic virus and potato virus X.     

Die Herstellung polyploider Pflanzen mit Hilfe von Colchicin-Injektionen

Ohne Zusammenfassung     

Die Bestimmung des Solaningehaltes von Pflanzen mit Hilfe vonCladosporium fulvum

Ohne Zusammenfassung     

Untersuchungen zur Photosynthese-Induktion bei Chlorella mit Hilfe von radioaktivem CO2

Summary ¹⁴CO₂ fixation and radioactive products in Chlorella cells were examined during the induction period. Chlorella vulgaris (strain 211-11f) grown under low CO₂ concentration (0.03 vol.-%) was used in our experiments. No transients in ¹⁴CO₂ fixation could be observed under the conditions used (0.7 vol.-% CO₂). Autoradiographic studies of the kinetics of appearance of labelled products showed that at the beginning of the illumination period radioactivity appeared first in intermediates of the Calvin cycle (e.g. phosphate esters). After 2 min smaller amounts of radioactivity were incorporated in malate and aspartate. In another series of experiments the influence of iodoacetamide (0.001 M) on ¹⁴CO₂ fixation was examined. In Chlorella cells inhibited with iodoacetamide radioactivity was located in malate, aspartate and 3-phosphoglycerate only. Results were discussed with reference to the participation of two different carboxylation pathways in the formation of the transients. Also the possible role of photorespiration in these transients was discussed.     

Zur Frage der Zuordnung von Genen zu bestimmten Autosomen des Menschen mit Hilfe von Chromosomenaberrationen

A precise localization of a gene on a definite autosome has not yet been successful. We dispose only of some linkage data obtained from pedigree analyses. The classical methods of experimental crossing cannot be applied to man. The possibilities for a methodical approach towards the establishment of human chromosome maps has been substantially imporved by new methods in human genetics, especially cytogenetics. The authors provide a survey of the methods which can at present be used. These are based on the analyses of chromosome aberations, above all duplications and deficiences. Duplications may lead to (1) gene dosage effects, (2) triallelicaly controlled characters, (3) a deviation from frequency distributions which were theoretically to be expected of definite phenotypes. Deficiencies allow visualization of (1) gene dosage effects and (2) monoallelic characters in expected heterozygosity, as well as (3) the exclusion of a localization in heterozygosity. The methodological possibilities for each of these aspects are discussed, and the difficulties and limitations are alsommentioned. Finally, the experimental findings on each aspect are taken into consideration.     

Die Rückkehr der Wölfe. Das erste Jahrzehnt

The first decade: the return of the wolves Wolves returned to Saxony in the year 2000 since then they have been regularly rearing pups. Nowadays at least 60‐80 wolves are living in Germany. To face its attendant conflicts a wolf management has been installed including wolf monitoring, public relation work and damage compensation. According to the monitoring wolves feed almost completely on wild ungulates, whereas livestock does not play a major role. The wolves' natural origin from north‐eastern Poland could be proven by genetic analyses. By the use of radiotelemetry important information could be gained on the adaption of the wolves to the anthropogenic landscape.     

Speichelforschung im Zoo - Eine Hilfe zur artgemäßen Fütterung von Tierarten mit besonderer Nahrungsanpassung

Between 2008 and 2010 the Zoological gardens in Rheine, Stuttgart, Karlsruhe, Cologne and Zurich took part in a research project initiated by scientists of the Institute of Animal Science, University of Bonn. Saliva was collected from various zoo animals to determine certain dietary adaptations on enzymatic and physiological levels that might explain or change our current understanding of animal nutrition and the feeding in zoo environments. The interest was primarily focused on species with specialized nutritional needs or fermentation strategies such as geladas, chimpanzees, camels and zebras. The work produced highly valuable data especially on geladas, which, despite from their adaptation to grass diet, revealed to have the enzymatic precondition (salivary amylase) to use starch-rich food items very effectively. Therefore, to prevent obesity in captive geladas, the reduction of starchy food in their daily rations is mandatory. Finally, saliva sampling is an easy, cost-effective and non-invasive procedure, the use of which is both practical and attractive in a zoo environment. In the future, the world-wide emerging field of salivary research might give birth to new applications of saliva as a tool to detect biomarkers of physiology and diseases in zoo animals.