Physiological and metabolic phenotyping
1. Metabolic Phenotyping
- TSE labmaster
- EchoMRI-700
- Thermostatic chamber (warm 20°C to 35°C)
- Calorimetric bomb
- Cobas C111
- Infrared camera (FLIR E60 C05.1531a and FLIR new animal facility)
- Metabolic cages1
1. Metabolic Phenotyping
- Treadmills (calorimetric or open flied)
- Running wheels
- Rotarod
- Grip test
- rOyymetre (SpO2)
- CODA Arterial Pressure
- Telemerty (EEG, ECG, EMG, BP, Glycemie, activity)
Equipment for 16 mouse cages and 12 rat cages.
The LabMaster provides the following measurements:
- Calorimetric parameters (O₂ consumption, CO₂ production, respiratory exchange ratio (RER), energy expenditure, cage temperature)
- Water intake
- Food intake
- Locomotor activity (exploration, fine movements)
- Changes in body weight
LABMASTER PROCEDURES
The experiment takes place over one week. The user brings the animals on Monday morning after having performed an EchoMRI. The animals are placed in the machine and monitored until the following Monday.
- First habituation period (approximately 24 hours): the animals are transferred as a group to the LabMaster cages.
- Second habituation period (3 to 4 days): the mice are housed individually in the different LabMaster cages. From this point onwards, experimental data are collected.
- The recording phase can generally begin on Friday or Saturday. The experimental data are then collected, and the animals are returned to the user, who must measure body composition by EchoMRI (required for the expression of the results).
The results are first analyzed by the Core Facility to ensure that the parameters obtained are correct.
Interpretation of the results, detection of possible aberrant values, statistical analysis (ANCOVA), graphical representation of the data, and preparation of animal experimentation authorization applications may exceptionally be carried out by the Core Facility. For more information, contact Prof. Roberto Coppari
TO BE PROVIDED BY THE USER
The animals and their food.
LABMASTER RESERVATION
Contact Dr. Franck Bontems to determine the experiment schedule (machine availability and the persons responsible for the practical aspects of its operation).
Rules for using the LabMaster
- The LabMaster can be booked for one or more weeks (from Wednesday to Wednesday), depending on availability.
- Users will be charged the full rate at the time of booking (CHF 1,850/week).
- Cancellation policy: If users cancel 2 weeks before the start of the experiment, they will be refunded.
- If someone else is interested in booking the LabMaster when it has already been reserved, this person should inform the Core Facility and will be contacted as soon as the LabMaster becomes available (in the event of cancellation).
- Monday morning: users bring their mice (maximum 16 mice plus 1 extra per group).
- Users must inform the Core Facility of the following five points:
- Number of mice and groups (controls, KO, males, females, special food, special drinks, etc.).
- Number of animal cages brought at the beginning of the experiment.
- Whether they plan to interact with the animals during the experiment (food restriction, injection, food changes, body-weight monitoring, etc.).
- The temperature of the experiment (6 °C to 35 °C).
- Whether they wish to test a food or drink preference.
ANIMAL HEALTH STATUS
The use of animals originating from animal facilities outside the CMU must first be approved by the Veterinary Service of the Faculty of Medicine. A recent health certificate from the animal facility of origin, including a health history covering the previous 18 months, must be sent to the Veterinary Support Service (), before any animals are imported.
This step must be carried out when the project is initiated in order to assess the feasibility of importing the animals. Some animals may be refused if their health status is not adequate.
Depending on the animal facility of origin, a quarantine period of several weeks may be required before the animals can be used on the platform.
Any animal presenting health problems (injury, infection, abnormal behavior) will not be admitted to the LabMaster, in order to prevent potential problems for other users and to take into account the fact that it is aberrant to study an animal in poor health.
Advice:
For optimal results, two groups of 8 to 9 animals (including one backup by group) are recommended for the 16 cages. Exceeding 4 groups with very low sample sizes is discouraged.
It has never yet been possible to obtaining significantly different results with a single experiment involving more than 4 different groups of animals (n<4 animals per group)
- 4 groups with n=4 is the limit for obtaining a satisfactory result, although it will generally be necessary to repeat the experiment
- Even when repeating the experiment, n=3 animals per group, is the extreme limit for carrying out an experiment.
- Below 3 animals per group in each phenotype (n=2 or n=1, even when repeating the experiment several times) the results will be disappointing and not reproducible and it will be impossible to perform a correct analysis.
- Animals may be brought in excess to replace a potential outlier at the beginning of the experiment (e.g. an animal that does not eat or drink properly).
- Animals should have a homogeneous body weight (variation < 15%).
- Experiments characterizing movement (closely related to behavior), such as voluntary running-wheel activity or movement inside cages, should be performed with a minimum of n = 6 animals (therefore only 2 or 3 groups maximum).
Physical test apperatus
Applications include drug screening (evaluation of the effects of potentially toxic products, drugs or vaccines), neuromuscular diseases, Parkinson's disease, Huntington's disease, aging studies, and studies involving brain injury.
Endurance, effort resistance ...
Grip test
The grip test assesses neuromuscular function in rodents.
Because this test is often operator-dependent, it is performed by the Core Facility.
Rotarod
A performance test used to quantify the animal's ability to remain on a rotating horizontal rod.
It measures holding time and/or endurance and/or coordination.
Because this test is often operator-dependent, it is performed by the Core Facility
Two types of treadmills
1) Calorimetric treadmills
These four treadmills are connected to the LabMaster in order to obtain calorimetric parameters during exercise as part of experiments studying metabolism or muscle properties.
Three phases are required:
Day 1 – Habituation
- 5 min – 0 m/s – inclination 0°
- 5 min – 0 m/s – inclination 10°
- 5 min – 0.15 m/s – inclination 10°
Day 2 – Habituation
- 5 min – 0 m/s – inclination 0°
- 5 min – 0 m/s – inclination 10°
- 5 min – 0.15 m/s – inclination 10°
Day 3 – Recording
- 5 min – 0 m/s – inclination 0°
- 5 min – 0 m/s – inclination 10°
- 5 min – 0.08 m/s – inclination 10°
- 5 min – 0.15 m/s – inclination 10°
- 5 min – 0.20 m/s – inclination 10°
- 5 min – 0.25 m/s – inclination 10°
- …
A new protocol appears to be less stressful for the animals:
Graded Maximal Exercise Testing to Assess Mouse Cardio-Metabolic Phenotypes – Jennifer M. Petrosino (2016).
The new protocol is described in four phases:
Day 1 – Habituation
- 3 min – 0 m/s – inclination 0°
- 5 min – 0.1 m/s – inclination 0°
- 2 min – 0.15 m/s – inclination 0°
- 2 min – 0.2 m/s – inclination 0°
Day 2 – Habituation
- 3 min – 0 m/s – inclination 0°
- 5 min – 0.1 m/s – inclination 0°
- 2 min – 0.15 m/s – inclination 0°
- 2 min – 0.2 m/s – inclination 0°
Day 3 – Habituation
- 3 min – 0 m/s – inclination 0°
- 5 min – 0.1 m/s – inclination 0°
- 2 min – 0.15 m/s – inclination 0°
- 2 min – 0.2 m/s – inclination 0°
Day 4 – Recording
- 3 min – 0 m/s – inclination 0°
- 2 min – 0.1 m/s – inclination 0°
- 2 min – 0.15 m/s – inclination 5°
- 2 min – 0.2 m/s – inclination 10°
- 2 min – 0.25 m/s – inclination 15°
- 1 min – 0.3 m/s – inclination 15°
- 1 min – 0.35 m/s – inclination 15°
- 1 min – 0.383 m/s – inclination 15°
- 1 min – 0.40 m/s – inclination 15°
- …
This new exercise protocol is increasingly used because it is closer to the tests performed in humans.
- The duration is greater than 6 min.
- More importantly, the duration is generally less than 12 min, compared with up to 45 min for the previous protocol.
A progressive increase in speed combined with an increase in inclination provides more reproducible performance data and thus reduces the number of animals required.
Link :
2) Open treadmills
These treadmills are connected to a computer in order to obtain parameters and recorded data without calorimetry.
Movie link : Assessment of Murine Exercise Endurance Without the Use of a Shock Grid: An Alternative to Forced Exercise
EchoMRI-700 – CMU, basement, laboratory 208 (former animal facility) – Tel. 022 379 52 16
Measurement of body composition by EchoMRI-700™ in awake rats and mice.
Determination of fat mass, lean mass, free fluids (urine), and total body water.
Measurements take 1 to 2 minutes in rats and 2 to 3 minutes in mice, without anesthesia or sedation.
Link :
Thermostatic chamber – Room D02.1953a
The incubator can contain a maximum of 32 mouse cages (21 × 32 cm), 24 cages with filters (20 × 40 cm), 16 small rat cages (43 × 30 cm), or 8 large rat cages (34 × 56 cm). The number of animals authorized per cage must be respected.
To ensure the proper functioning of the climate-controlled chamber, the maximum number of cages must be respected.
The chamber temperature can be set between 20 and 35 °C. Humidity can be modified (55% ± 15%).
Finally, the day-night circadian cycles can be determined by the user (minimum interval of 30 minutes).
For practical details (e.g. cage changes during an experiment), contact a coordinator.
For requests for equipment (cages, food, etc.), please allow at least 1 week in advance.
As for the LabMaster, the cancellation policy is as follows: if users cancel 2 weeks before the start of the experiment, they will be refunded.
RESERVATION (3 months maximum)
Contact Dr. Franck Bontems
Link :
Infrared camera FLIR E60 – Room C05.1531a – Tel. 022 379 52 16
Characteristics:
Infrared camera for measuring the surface temperature of an animal.
Detection range: −20 to 650 °C.
Detection: 320 × 240 pixels.
Video camera with lamp and laser: 3.1 MP video, LED lamp, and laser pointer.
Digital zoom: 4× continuous.
Examples of use:
- Cell. 2013 Sep 26;155(1):172–87.
- FASEB J. 2012 Aug;26(8):3483–92.
Link :
Mice running wheels – Corridor D02
These are wheels (10.15 cm in diameter) designed for installation in standard cages covered with a grid. The spontaneous activity of the animals is continuously measured. This is done using a PC program that requires a cable coming out of the cage and an external USB interface.
RESERVATION
Contact Dr. Franck Bontems Tel.: 022 379 52 16
Link :
http://www.colinst.com/brief.php?id=47
Calorimetric bomb – Room C05.1741a
The calorimetric bomb is used to determine the calorimetric energy of a sample.
The samples generally tested are feces or food from animal laboratories. If the mass of food consumed and the mass of feces produced are recorded for each animal, it is possible to calculate energy absorption.
Digestible energy (cal) = (Mass of food (g) × caloric energy of food (cal/g)) − (Mass of feces (g) × caloric energy of feces (cal/g))
Note: Other types of samples can be analyzed to determine their energy values (tissues, biological fluids, etc.). Contact a coordinator.
RESERVATION
Contact Dr. Franck Bontems to determine the experiment schedule (machine availability and practical aspects of its operation).
Sample recommendations
For one measurement, a minimum of 0.25 g of dried fecal matter, finely powdered, is required.
Price per measurement: CHF 20.– (triplicate: CHF 60.–).
Cobas C111 – Room C05.1741a
The Cobas C111 is intended for the analysis of samples (blood/serum/plasma/urine).
It allows the measurement of the main analytes in animals and/or humans (see table below).
RESERVATION
Contact Dr. Franck Bontems / Tel. 022 379 52 16 to determine the experiment schedule (machine availability and practical aspects of its operation).
Important information
The COBAS is an instrument normally used for the analysis of human samples. Some analyses use antibodies against human proteins; therefore, the results obtained cannot be guaranteed for assays performed on samples from laboratory animals.
Dead volume: 50 µL per sample.
The CODA™ system was designed to allow accurate measurement of blood pressure in mice and rats. Blood pressure is measured in the tail of the mouse or rat using specific Volume Pressure Recording (VPR) sensors. The software allows continuous real-time visualization of the data.
Animal habituation is performed over a period of 3 to 4 days, followed by measurements over 4 to 5 days maximum. Groups of 8 mice are recommended (same age, same sex).
RESERVATION
Contact Dr. Christelle Veyrat-Durebex.
MouseOx Plus® Oximeter
Physiological data:
- Arterial oxygen saturation (SpO₂)
- Respiratory rate
- Respiratory distension
- Heart rate
- Pulse distension
- Non-invasive
- Anesthetized and awake animals
- Paw sensor (mice > 5 g) or neck sensor (unshaved mice > 15 g; shaved mice > 20 g; young rats 5–30 g)
Price: CHF 50 for half a day.
Attention : If the animal is awake (neck sensor), a habituation session is required.
Metabolic cages ; corridor D02.2052a
12 metabolic cages are available and can be used for 24-hour periods. They allow urine and feces to be separated from 12 animals simultaneously, enabling different types of measurements:
- Phenotyping.
- Calorimetric evaluation of feces (calorimetric bomb).
- Urine and feces volume/weight.
- Protein excretion.
- Therapeutic effects of drugs.
- Functional renal studies.
RESERVATION
Contact Dr. Franck Bontems to determine the experiment schedule (availability, persons in charge of practical aspects).