Comparative evaluation of a commercial microdilution method and a conventional disk diffusion method for determination of antibiograms of gram-positive cocci

A commercial broth microdilution system for testing the antimicrobial susceptibility of gram-positive cocci was compared with the standardized disk agar-diffusion method by testing 254 clinical strains of staphylococci and streptococci using both methods. A total of 2,794 parallel determinations were made with 92.3% complete agreement between the 2 methods; of the discrepancies encountered, 3.0% were minor, 2.5% were major, and 2.1% were very major. The results indicate that the commercial microdilution system may provide a reliable quantitative method for antimicrobial susceptibility testing of clinical isolates from animals.     

Determination of the transit rates in different sections of the pig's intestine

An experiment was carried out using pigs weighing approximately 30 kg. The animals were fitted with two re-entrant cannulas in duodenum and ileum. During a 5 day period the passage of digesta through duodenum and ileum as well as the excretion by urine and faeces was estimated, taking an aliquot of 5% for N analysis. Transit of digesta amounted to 12.4 ... 13.2. kg/d in the duodenum and 2.7 ... 3.6 kg/d in the ileum. The appertaining N passage rates were 36.8 ... 42.4 resp. 8.7 ... 11.2 g N/d, corresponding to 108 ... 120% and 27 ... 32% of the N intake. The transit rate of duodenal digesta was highest immediately after feeding (1.4 ... 1.5 kg/h), decreased thereafter strongly, reaching a second lower maximum of 0.85 ... 1.0 kg/h 2 ... 3 h after feeding and then going down to 0.3 ... 0.4 kg/h just before the next feeding. The daily mean value was about 500 g/h. Endogenous N content of duodenal digesta varied between 10% after feeding and 50% 6 ... 12 h after feeding, with an average of 18.1%. In contrast the endogenous N content of ileal digesta was relatively constant amounting about 42% during the whole day. These findings correspond with those found by other authors using other rations and other live weights of the pigs. They refer to a clear diurnal rhythm of digesta transit and to the enormous dynamics of absorption and secretion processes in the intestinal tract of pigs during digestion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Zur Massenvermehrung des Schlehenspinners,Orgyia antiqua (L.) 1971/72 in Bayern

Summary On an outbreak of Orgyia antiqua L. (Lepid., Lymantriidae) at Memmingen, Bavaria, 1972.The number of larvae ofO. antiqua on pine trees at Memmingen reached its high level during autumn 1971. About 350 ha mainly the old trees were infested. The number of egg masses per stem was more than 42 in max. with an average of 205 eggs per egg mass (n = 40). The percentage of hatching was found to be 74,5%. The rest of the eggs was mainly parasitized byTelenomus dalmanni (Ratz.). The pest had only one generation. The old larvae were infected with a virus disease and a great part of pupae was killed by fungi. These two diseases were the main factors in regulating the population ofO. antiqua.     

Aufgaben und Ziele der Landschaftstechnik im Rahmen der forstlichen Ausbildung

Summary Landscape management, defined as measures and means for the protection and restoration of landscape damages, is neither landscape planning nor forest management policy on an ecological basis but rather a technical discipline in the field of ecology. The problems of recreation management also belong to landscape management. Preliminary for this view is that deeper informations are given about landuse and landscape planning in other subjects (courses). Special problems like those given by the development of the region of the alps should be discussed in a more advanced education program.

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Vortrag gehalten vor der Forstwiss. Fakult?t in München, Mai 1974.     

Accurate determination of the limiting viscosity number of pulps

The viscosity of copper ethylenediamine (CED) solutions of pulps exhibits a decrease with time, while the viscosity loss is insignificant when the time between dissolution and measurement is just 15–20 min. Time of 1 h or longer would lead to noticeable differences from the initial viscosity. The viscosity of the solution at the beginning can be estimated from a series of measurements performed under strict conditions. In particular, tight control of the temperature of the solution and accurate measurement of the flow time are of importance. The plot of efflux times against elapsed times to the measurements results in a almost linear correlation, which enables to determine the initial viscosity.