General Health & Activity Levels
Several customized behavioral tests are offered to phenotype mouse and rat models and evaluate effects of compounds in different in vivo models.
New behavioral tests are continuously developed and validated.
|In the cylinder test the spontaneous activity of rodents can be measured. The animal is placed in a transparent Cylinder. The animals behavior is recorded from the bottom for 3 minutes. It is measured how often the animal shows rearing behavior, how many steps with the fore and hind limbs are performed and how much time the animal spends grooming.|
Glucose Tolerance Test
The glucose tolerance test is a standard procedure to test for insulin resistance. Specifically, the uptake of glucose from the blood by cells is regulated by insulin. An impairment of the uptake speed indicates problems with the maintenance of glucose homeostasis (e.g. diabetes, obesity and cardiovascular diseases).
To measure glucose tolerance, mice are fasted overnight before blood is collected for measuring baseline blood glucose concentrations. Subsequently, a single dose of a 20% glucose solution is applied intraperitoneally prior to additional blood glucose concentration measurements at 15, 30, 60 and 120 min post injection.
|Assessment of glucose tolerance in C57BL/6 mice treated with high fat diet for 12 weeks. Blood glucose level measurements per group measured at baseline (A), after 6 weeks (B) and 12 weeks (C) of high fat/control diet. Mean ± SEM. n = 10 per group. Two-way ANOVA with Bonferroni´s post hoc test. *p<0.05; ***p<0.001.|
The Irwin test is a general health check for rodents.
Using the Irwin test in mice, physical characteristics and conspicuities, sensorimotor reflexes and motor abilities are checked by an experienced observer.
Using the Irwin test in rats, physical characteristics and sensorimotor reflexes as described for the mouse (see above) are measured.
Additionally rats are tested in the following tests:
- Inclined layer test (tilted platform test, balance)
- Grasping reflex (sensorimotor reflex)
- Chimney test (spatial orientation)
- Cliff hanging (muscle strength)
|Body weight of 6 month old 5xFAD transgenic mice. Body weights separated by sex. n = 6 per group. Mean + SEM. t-test. **p<0.01; ***p<0.001.|
Nest Building Test
Nest Building Test
Nesting behavior is a simple and versatile behavioral test suitable for the evaluation of motor deficits. Nest building is an intrinsic behavior performed by male and female rodents that requires fine motor skills.
Nest Building Behavior in Mice
To test the individual Nest Building Behavior, mice are individually housed in cages containing wood chip bedding and one square of pressed cotton (`nestlet´). No other nesting material is provided. The following morning the manipulation of the nestlet and the quality of the built nest are assessed manually according to a five-point scale.
Nest Building Behavior in Rats
The ability of rats to build nests is assessed by offering the animal wood whool nesting material that is placed into the metal grid next to the food pellets.
In the evening, rats are provided with nesting material. The following morning, the quantitative amount of nesting material that was actively pulled into the cage, as well as the quality of the nest is assessed. The unused nesting material is thus weighed and recorded, and photographs of the nests are taken and analyzed manually by an experienced experimenter.
|Nest building behavior in 2, 3 and 6 month old Line 61 mice compared to non-transgenic littermates. n = 11 – 15; Mean + SEM; Two-way ANOVA with Bonferroni’s post hoc test. *p<0.05; ***p<0.001.|
Open Field Test
The Open Field Test is used to test rodents for activity and anxiety.
A Plexiglas Open Field (TSE-System®) is used to test the activity of rodents. Infrared photo beams detect movements on the ground but also rearing (standing on the hind limbs). Testing is performed under standard room lighting conditions in naïve animals. The number of fecal boli is counted as measure of emotionality. A tracking system automatically measures the activity, hyperactivity, rearing, thigmotaxis, and distance traversed.
|Open field behavior of MK-801 treated C57Bl/6 mice. A: Distance traversed of MK801-treated animals compared to sham-treated controls. MK801-treated mice show increased locomotion starting 20 minutes after treatment. B: Hyperactivity level of MK801-treated animals compared to sham-treated controls. MK801-treated mice show increased hyperactivity levels starting 20 minutes after treatment. n = 10. Mean ± SEM. Two-way ANOVA with Bonferroni’s post hoc test. *p<0.05; p<0.001.|