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A goal of improvement of crob breeding and food processing is to increase the nutritional quality, which is related to the availability of nutrients. This paper describes a dynamic, computer-controlled system that mimics to a high degree the successive kinetic conditions in the stomach and intestines. The system has been validated in comparison to human and animal studies for a broad variety of applications, and showed a high extrapolation value. It is used successfully for the assessment of nutritional quality and the development of novel and functional foods.

It is well documented that the indigenous microflora, particularly in the colon, plays an important role as a natural resistance factor against pathogenic microorganisms. The number of beneficial bacteria can be increased by specific non-digestible carbohydrates known as prebiotics. One category of prebiotic is inulin, a non-starch poly-saccharide consisting of chains of fructose units coupled by β(2,l)-bonds, frequently terminated by a single glucose moiety naturally occurring as a storage carbohydrate in many plant species. From the results of various in vitro and in vivo studies in animals and humans, inulin can be considered a prebiotic with a bifidogenic factor: it selectively stimulates the in vivo growth of bacteria such as Bifidobac-terium, Lactobacillus, and Bacteroides at the expense of potential pathogenic microorganisms. Regarding safety, the tolerance level for inulin is far above the bifidogenic level.

In order to obtain practical experience on the recognition, assessment and evaluation of discomfort in laboratory animals, the degree of discomfort was studied in gallstone-free and gallstone-bearing mice. Out of nine parameters to which scores were assigned per individual mouse, only the response to palpation of the right hypochondrium was found to score significantly higher in gallstone-bearing mice. That is, the incidence of squeaking and the magnitude of muscular contractions were significantly higher in these animals compared with the gallstone-free mice. The stance of the gallstone-bearing mice also tended to be abnormal, although the difference between gallstone-free and gallstone-bearing animals did not reach statistical significance. Although this study does not prove unequivocally that the induction of gallstones per secauses discomfort or pain in mice, we tentatively conclude that it does. We feel that this should be taken into account in any projected work in which gallstone induction in animals may occur. There was considerable between-assessor variation in the assignment of scores to the variables used to assess discomfort, including the response to palpation. It is concluded that the selection of parameters and the experience and/or attitude of the assessor are critically important when the magnitude of discomfort, if any, is assessed in experimental animals.

This study was conducted to validate a dynamic model of the stomach and small intestine to quantify the survival of lactic acid bacteria and to assess the influence of gastrointestinal secretions. The survival of a single strain of each of the following species, Bifidobacterium bifidum, Lactobacillus acidophilus, Lactobacillus bulgaricus, and Streptococcus thermophilus, was measured under physiological conditions (e.g., peristalsis, changes in pH, and changes in concentrations of enzymes and bile) and were compared with data obtained from humans. No significant differences were found between the in vitro and in vivo data, indicating that the model has a predictive value for the survival of these bacteria in humans.

In a previous study, a single external treatment with Ivomec appeared to be more effective than Neguvon treatment. In this study the anti-endoparasitic qualities of external application of Ivomec were investigated, together with the effectiveness of a combined Neguvon and Ivomec treatment. After 3 treatments, all mice were mite- and worm-free: they remained free of ectoparasites until 18 weeks after the last treatment; eggs of endoparasites reappeared 9 weeks after the last treatment.

The current systems for classifying human pathogens on the basis of hazard are well developed and their basic criteria are in general agreement one with another. Of more importance, the safety practices based on these classifications have generally been successful. They have enabled extensive research activities, medical practice and industrial production to be conducted on an ever-increasing scale, involving dangerous microorganisms (e.g. in vaccine production and treatment of infected patients) with a very low incidence of adverse effects on the workers involved and the general public. Although the EU has adopted a harmonised list of agents in groups 1–4 there is as yet no complete agreement among member states and individual microbiologists. The purpose of this paper is to present a historical survey and to discuss the current processes for identifying and classifying the hazards posed by the use of microorganisms in research and technology. This is essential in the design of appropriate methods of counteracting potential risks.

Abstract: The assessment of microorganisms in respect to human health is an important step for the introduction of new natural and genetically modified production strains to biotechnology. This report outlines the potential hazards posed by industrial microorganisms, important considerations related to pathogenicity, such as routes and portals of entry into the human body, mechanisms of spread of biological material and a definition of pathogenicity.Furthermore the most important steps in the assessment of pathogenicity of unknown strains are described. A short overview on characterization and in vitro and in vivo tests is presented. The hazard related to allergens and toxic metabolites is reviewed and the choice of methods and the handling of strains with unknown potential are discussed.

Abstract: The transport of infectious and biological material is regulated by a number of international organizations. This mini-review has been compiled to increase awareness within the scientific community of problems caused by differences in terminology (such as infectious materials/substances, biological products, diagnostic specimens, genetically modified microorganisms) and certain technical aspects of the main international guidelines, and to assist policy makers in the creation of harmonized guidelines. A list of relevant Internet resources has been compiled.

The effectiveness of different methods of external applications of Neguvon and Ivomec for treating infestations with Myobia musculiand Myocoptesspp. in conventional colonies of laboratory mice was investigated.Ivomec appeared to be effective over a longer period of time than Neguvon. There was no difference in the results obtained with different methods of application, but spraying seems to be more practical for large colonies of mice than individual dipping.