Report from »Symposium fiber Hamster und Gerbil«

No abstract availabl

Are We Using the Most Appropriate Animals for Our Research and Are We Doing It for the Best Reasons?

Over the last 50 years there have been demands to increase the quality of animals used for research. The  numbers of animals used for individual projects have in the same period decreased, while the efforts put on  the single animal to secure the highest scientific output from it have increased. Basically this is a very  important part of both “refinement” and “reduction”; those two of the three R’s which, it previously has  been argued, were less in focus than the last R, ‘replacement’ (Nevalainen, 2005).

Considering the microbiota to achieve reduction in the numbers of animals used in scientific studies

Elimination of pathogens by laboratory rodent commercial vendors has substantially improvedstandardized conditions as well as laboratory animal welfare. However, pathogensare also important for basic activation and functioning of the immune system withconsequential influences on the symbiotic bacteria composition in the individual microbiota.One of the reasons for failures of translating results from preclinical researchto the clinical phase in some studies could be due to unintentional selection processes.Some recommendations are provided to increase researchers’ awareness on this point,together with a practical checklist to optimize information from microbiota knowledge

The aerobic bacterial flora of laboratory rats from a danish breeding centre

The aerobic bacterial flora of barrier-maintained laboratory rats from 12 ditferent units was examined by the use of non-seleetive bacteriological cultivation. All rats were randomly sampled healthy rats. The number of infected clonies out of thetotal number of examined colonies is given with the mean prevalence observed within the colonies for each of the bacterial species identified. The minimal sample size for detection of the organisms in routine microbiological] monitoring is estimated on basis 01' the prevalences observed. Bacterial species from the groups Micrococcaceae, Streptococcaceae, Lactobacillus spp, Bacillus spp, Corynebacterium spp. Enterobacteriaceae, Neisseriaceae, Pasteurellaceae and Pseudomanadaceaewere found. The most frequently isolated species was Staphylococcus aureus in the respiratory organs and Escericia coli in the intestines. The prevalence of the different bacterial species within the colonies varied from 3.1 to 69.3. The minimal sample size for each bacterial species varies from 3 to 95

Statistical aspects of health monitoring of laboratory animal colonies

Sample size, sampling frequency and the importance of random sampling in health monitoring of colonies of laboratory animals are discussed and the terms nosographic sensitivity (N1), nosographic specificity (N2), diagnostic sensitivity {D1}, and diagnostic specificity (D2) are explained. It is concluded that test systems with a diagnostic specificity above 0.95 should be chosen, while a low nosographic sensitivity can be accepted, if the sample size (S) is calculated from the formulain which p is the prevalence

An improved technique for the decontamination of barrier units contaminated with Bacillus piliformis strains of rat origin

Desinfection of animal units is normally based on the use of aldehydes as desinfectants. This article describes a technique for desinfection of animal units in which the use of glutaraldehyde is supplemented with the use of heat and peracetic acid.This method is, in contrast to the use of aldehydes alone, effective against spores of Bacillus piliformis of rat origin, which is in accordance with in vitro investigations

The application of traditional behavioural and physiological methods for monitoring of the welfare impact of different flooring conditions in rodents

In this study, observations on traditional methods, such as open field test, conicosterone assays and monitoring of barbiturate sleeping time, were performed to validate the impact of housing conditions on the welfare of rats and mice in orderto compare the outcome with observations previously achieved by preference tests and telemetry. These traditional methods failed to demonstrate the impact on the animals caused by grid housing previously shown by telemetry and preference studies, and it is, therefore, concluded that these traditional tests may be less sensitive for monitoring Subtle small environmental impacts on laboratory rodents.Although. the methods were not able to reveal any differences in eortieosterone level and open field test between housing conditions, there were significant differences between mouse strains and sexes. These differences between strains should betaken i nto account when choosing the best suitable strain for a study

Weighing used for the automatic registration of preferences when testing rats

The preference test is one of the only behavioural test, which gives the animal an opportunity to make a free choice or indicate what it prefers and, therefore, it is widely used to evaluate whether an animal prefers one set-up to another. Providingwhat the experimental animal prefers (eg grids) will reduce stress, good for both experimental reliability and animal welfare.In the present study the rat’s preference for different cages was registered and recorded by digital weights This study showed that this relatively simple set-up was applicable for registration of the preferences for different housing conditions, such as bedding or grid

Strain restricted typing sera for the use in the genetic monitoring of inbred strains of mice and rats from two danish SPF breeders

Strain restricted typing sera (SRTS) were produced for some of the most used inbred mouse and rat strains in Denmark by injecting lymphocytes pooled from several different strains intraperitoneally into the recipients. The SRTS were combined with a complement dependent cytotoxieity assay. It was possible to distinguish animals from strains with different MHC haplotypes but not animals from strains with the same MHC haplotype. It was concluded that the SRTS eomhined with a  complement dependent cytotoxicity assay could distinguish between some of the most commonly used inbred strains of rats and mice in Denmark