Praktiske studier på dyrevelfærd

Characterizing the intestinal flora in mice
Abstract:
The composition of the intestinal flora has an influence on the development of human autoimmune as well as metabolic diseases, and is in that connection an important factor in immunological as well as in metabolic disease models. Studies have proven a strong correlation between the composition of the intestinal flora and disease development, and it is reasonable to believe that a reduction in variation in the composition of the intestinal flora will also lead to a more homogeneous disease outline. Thus the smaller the variation in disease parameters, the smaller groups are needed for each study.

In this study we want to characterize the variation in the composition of the intestinal flora in mice, including the genetic as well as the environmental influence on the intestinal microbiota. Furthermore we want to clarify to which extent it is possible to reduce this variation in mice used for immunological as well as metabolic test studies.

 

The effects of single housing on the welfare of rats and mice

Abstract:

It is a common assumption that housing mice and rats individually may be a stressful experience. Both mice and rats are social species, and a part of the natural behavioural repertoire is social behaviour. So by housing the animals singly the behaviour repertoire of these animals is reduced.

In the biomedical research there is a need for housing rats and mice singly occasionally, therefore it is important to find the best way of doing this without compromising the welfare. Therefore two questions will tried to be answered:

· How is the cage size influencing the welfare of the animals when housed alone

· How is the environmental enrichment influencing the welfare of the animals when housed alone

In the study different kind of methods are used such as behavioural tests, observations, physiological parameters, Corticosterone level and other parameters.

 

Optimizing the surgical procedure for chronic vascular cannulation in laboratory rats

Abstract:
The goal of this project is to find out if the amount of catheter related infection can be significantly reduced by introducing proper aseptic surgery conditions, or using an antiseptic catheter material (heparin coated PU). At H. Lundbeck A/S they are currently not using aseptic surgery, and the catheter material is simple uncoated PVC.
30 male Sprague Dawley rats weighing app. 250g will be divided into 3 groups. One group will be operated on using the current procedure at H. Lundbeck (not aseptical and PVC catheter). The second group will be operated on using an aseptic procedure, but using the PVC catheter. The last group will not be operated aseptically, but will have a heparin coated PU catheter implanted. The presence of catheter related infection will then be evaluated by the following parameters:
The rats temperature, as a rise in temperature can be consistant with fever and thus acute infection. All rats will have a thermal chip implanted to monitor their temperature.
Daily serum samples will be taken to monitor the level of acute phase reactants (Haptoglobin or C-reactive protein) by ELISA.
At necropsy, the catheter tip, as well as a piece of catheter from the subcutaneous tunnel, will be examined for bacterial growth (sonication and culture), and the number of CFU will be assessed.
The kidneys will be examined for gross lesions of infection, and a swab of the renal pelvis will be cultured for bacterial growth.
Lastly, a sample of blood will also be cultured for growth.

 

The influence on animal welfare and research results when using music in the animal facility

Abstract:

In some facilities it common practice to play radio, but depending on the volume of the radio, and possibly on the program (music, talk-shows, or classical music) it could be expected that this may affect the animals in some ways.
In the present project many different aspects of the effects of music and noise on rats will be tested.

The following questions will tried to be uncovered:

· Are rats able to hear the music ?

· Are rats able to distinguish between different kind of music and noise ?

· How is music and noise affecting the physiology and behaviour of the rats ?

· Is there therapeutic effects of music or noise on the rats ?

· Is the staff more calm and relaxed towards the rats if they hear their favourite music ?

 

The effect of enrichment by the use of the Scantainer-Novo Rat Cage System on the development of diabetes in female NOD (Non-Obese Diabetic) mice

Abstract:
This study is one in a row of studies to explore the effect of different environmentally enriched housing conditions on various ”scientific” parameters. The aim of this specific study is to evaluate the effect of different housing conditions on the development of spontaneous insulin-dependant diabetes in female NOD mice. Mice will from the age of weaning, approx. 4 weeks old, be housed under one of three different environmentally enriched conditions; non-enriched in a standard type IV cage with aspen bedding, semi-enriched in a standard type IV cage with aspen bedding, paper nesting material, and a biting stick, or fully enriched in a Scantainer-Novo type IV cage, aspen bedding, paper nesting material, a biting stick and a hide. All mice will be weighed once weekly and blood glucose will be measured once weekly from the age of 8 weekly to evaluate diabetes onset and incidence.

 

The effect of alternating single housing and pair-housing in SD rats

Abstract:
In biomedical research, single housing of rats is often used in feeding paradigms, when using catheterised animals, when applying test-substances to the skin ect. Using the semi-contact cage, the aversiveness of being separated is sought to be reduced. The semi-contact cage is a type IV cage modified using a barrier consisting of a transparent Plexi-sheet perforated by 6 mm holes all over that separates the cage into two distinct compartments with separate food and water supply. However, using the semi-contact cage may increase the frustration of being separated due to the close visual and olfactory contact combined with no possibility to interact physically.
This study aims at evaluating whether housing in a semi-contact cage is preferred by the rats compared to being housed alone.  Moreover, we want to explore the resulting behaviour and physiology of single housed animals being housed alone for longer periods compared to pair-housed animals subjected to alternating separation with or without use of the semi-contact cage.

 

The effect of enrichment by the use of the Scantainer-Novo Rat Cage System on various behavioral and physiological parameters

Abstract:
This study is one in a row of studies to explore the effect of different environmentally enriched housing conditions on various behavioral and physiological parameters. The aim of this specific study is to evaluate the effect of different housing conditions on different behavioral tests and physiological parameters, as well as the general well-being under the different housing conditions.
Rats will from the age of weaning, approx. 3 weeks old, be housed in 12 to 14 weeks under one of three different environmentally enriched conditions; non-enriched in a standard type IV cage with aspen bedding, semi-enriched in a standard type IV cage with aspen bedding, paper nesting material, a biting stick and a hide, or fully enriched in a Scantainer-Novo type IV cage with an in-build shelter, aspen bedding, paper nesting material, a biting stick and a hide.
During the housing period, the water-intake, the weight gain and the use of the rats’ use of space in the cages are registered. After the pre-study housing period, the rats are tested in Open-Field-test, Elevated Plus Maze and Morris Water Maze. Also the rats are challenged by Amphetamine in the Open-Field-test. Also different Clinical Chemistry parameters are analyzed.

 

The effect of enrichment by the use of the Scantainer-Novo Rat Cage System on the tail bleeding in normal and heparinized rats

Abstract:
This study is one in a row of studies to explore the effect of different environmentally enriched housing conditions on various parameters, as well as the influence of different housing conditions on the outcome of animal studies.
The aim of this specific study is to evaluate the effect of different housing conditions on standard and heparin induced tail bleeding time and bleeding volume in Sprague-Dawley rats.
Rats will from the age of weaning, approx. 3 weeks old, be housed in 12 to 14 weeks under one of three different environmentally enriched conditions; non-enriched in a standard type IV cage with aspen bedding, semi-enriched in a standard type IV cage with aspen bedding, paper nesting material, a biting stick and a hide, or fully enriched in a Scantainer-Novo type IV cage with an in-build shelter, aspen bedding, paper nesting material, a biting stick and a hide.
After this pre-study housing period, a standardized tail bleeding study is performed, where the rats are anaesthetized and a standardized tail bleeding is induced with or without preceding heparin-treatment in order to measure bleeding time and volume.

 

The effect of enrichment by the use of the Scantainer-Novo Rat Cage System measured by telemetry in Sprague-Dawley rats

Abstract:

This study is one in a row of studies to explore the effect of different environmentally enriched housing conditions on various parameters, as well as the influence of different housing conditions on the outcome of animal studies.

The aim of this specific study is to evaluate the effect of different housing conditions on blood pressure and heart rate in Sprague-Dawley rats.

Rats will from the age of weaning, approx. 3 weeks old, be housed in 12 to 14 weeks under one of three different environmentally enriched conditions; non-enriched in a standard type IV cage with aspen bedding, semi-enriched in a standard type IV cage with aspen bedding, paper nesting material, a biting stick and a hide, or fully enriched in a Scantainer-Novo type IV cage with an in-build shelter, aspen bedding, paper nesting material, a biting stick and a hide.

After this pre-study housing period, a standardized telemetric study is performed, where the rats will be telemetric measured for several consecutive days in order to measure blood pressure and heart rate and later compare these measurements between the rats housed under the different conditions.

 

The effect of enrichment by the use of the Scantainer-Novo Rat Cage System on the development of diabetes in BB rats

Abstract:
This study is one in a row of studies to explore the effect of different environmentally enriched housing conditions on various ”scientific” parameters.
The aim of this specific study is to evaluate the effect of different housing conditions on the development of spontaneous autoimmune type 1 diabetes and breeding performance in the (BioBreeding) BB rat.
Rats will from the age of weaning, approx. 3 weeks old, be housed in breeding pairs from the same litter under one of three different environmentally enriched conditions; non-enriched in a standard type IV cage with aspen bedding, semi-enriched in a standard type IV cage with aspen bedding, paper nesting material, a biting stick and a hide, or fully enriched in a Scantainer-Novo type IV cage with an in-build shelter, aspen bedding, paper nesting material, a biting stick and a hide.
All rats will be frequently weighed and daily screened for diabetes onset and breeding performance will be recorded as age of parents by first litter, number of offspring by birth, number of offspring by weaning and weight of offspring by weaning.

 

The impact of cage ventilation on mice housed in IVC-systems

Abstract: 
Individually ventilated cage systems (IVCs) are commonly used for housing mice today. The systems commercially available today have air changes from 30 times per hour up to 120 times per hour. To achieve a rate that high, the air must enter the cage with high speed, but in most systems the air stream is regulated and at animal level most systems have air speeds below 0.2 m/s.
In the present study, two experiments were conducted, one analysing whether an air speed below 0.2 m/s, at 0.5 m/s and at 1.0 m/s affects the mice, and another one analysing whether air changes of 50, 80 and 120 times per hour affect the mice.
In a preference test the mice were given a choice between two cages, one with air speed and one without. And a choice between two cages, one with air changes and one without.