MOTOR ABILITIES AND COORDINATION
The RotaRod system by TSE Systems allows for accurate and fast measurement of motor coordination and fatigue resistance in rodents. In the test, the animal is put on a rotating cylinder to measure the latency of dropping down from the cylinder. Up to 5 mice and 4 rats can be run at the same time. Each lane on the system is controlled by its own timer and operated independently and animal falls are automatically registered. Unique for this system, the software allows to define, store and automatically run speed profiles with up to 100 steps per profile; within each step the initial speed, final speed and acceleration/decelaration time can be defined. All RotaRod units are also equipped with a programmable reverse rotation mode. With its most flexible test protocols, performance differences between animals can be detected that are unparallelled by other systems.
The Centre is equipped with rotarod systems for mice and rats.
Grip strength meter
The TSE Systems grip strength meter is a device for measuring the grip strength of rodents.
This test can be used to seek for the effects of targeted mutations or quantify the effects of various substances on the muscular strength of the animal. The animal pulls a special grip which is mounted on a high precision force sensor. The value of maximum force exerted upon having to release the grip is transferred to the controlling computer. There are different grip specifications (mesh, trapezoid) or custom grips.
The Centre has grip strength meters for mice and rats.
Together with the existing devices for measurement of anxiety (elevated plus-maze and zero-maze, dark-light exploration test) we have the equipement for measurement of social interaction and behavioural despair (Porsolt test).
Sociability testing is a specific study of social behaviour and focuses on the behaviour of one animal towards the others. University of Tartu has acquired the sociability platform from Noldus Information Technology. There are several options to perform this test, all conducted in a three-chambered test apparatus. It could include the study of the animal’s interest in a social stimulus (a conspecific in a wired cage placed in one of the outer chambers), versus a neutral stimulus (an empty wired cage placed in the other outer chamber). In a preference test for social novelty, the two wired cages contain a familiar and an unfamiliar conspecific. A third variation involves testing the social preference for two different, but both unfamiliar conspecifics. In most cases the interest is measured by assessing the time spent in the same chamber or in close proximity to the familiar or unfamiliar other mouse.
The behaviour is recorded and scored with EthoVision XT program, a software for the reliable analysis of behaviour
Specific options for both mice and rats are available.
The Porsolt test is a test for studying the behavioural effects of antidepressants in small laboratory animals, i.e depression-like behaviour in rodents.
The animal is first put into a pretest for 15 minutes and made to swim in a a water cylincer it cannot escape from. In the second test session, the animal is again put into the cylinder, and videotaped. This time, the animal stays in the device for 6 minutes, of which the last 4 are automatically analyzed for the amount of time spent immobile. The amount of time spent immobile is taken as a measure of hopelessness. Typically, antidepressants decrease the immobility time.
The Centre acquired the Porsolt test devices from Med Associates Inc. The behaviour of animals is automatically scored by the EthoVision XT program from Noldus Information Technology.
Neurometer® electrodiagnostic sensory nerve conduction threshold (sNCT) testing equipment is unmatched in its ability to painlessly and non-invasively provide a functional evaluation of sensory nerve integrity. Established normative painless Current Perception Threshold (CPT®) values individually measure each of the three major sub-populations of sensory nerve fibers that comprise the typical sensory nerve. The CPT® evaluation permits the determination of neurological dysfunction from hyperesthesia/neuritis through hypoesthesia/neuropathy as well as monitoring the progression of nerve regeneration. The Neurometer® is unique among all sensory nervous system evaluation tests with these capabilities. The sNCT test reliably and accurately measures the function at any cutaneous site on the body including mucosal surfaces such as in the palate and the bladder.
MOTOR AND EXPLORATORY ACTIVITY
In addition to the existing computer-aided motility boxes (TSE Systems) we have PhenoTyper purchased from Noldus Information Technology.
PhenoTyper is an instrumented cage to measure and test the behaviour of laboratory rodents.
The PhenoTyper homecage contains, besides the PhenoTyper topunit, a food and drink station and a shelter to allow an animal to live inside the PhenoTyper home cage for days in a row. During its stay, spontaneous behaviours such as locomotor activity, place preference and shelter use are recorded on a continuous basis and analyzed with EthoVision XT’s video tracking technology. More over, the PhenoTyper system is equipped with infrared cameras, which makes it possible to track animal behaviour in the dark. Additionally to basic tracking, auditory and visual cues can be given separately for each cage in the system, depending on the conditions set in the EthoVision program.
The Centre is equipped with 16 PhenoTyper cages for mice and 16 PhenoTyper cages for rats making it possible to generate reliable results very quickly.
LEARNING AND MEMORY
Fear conditioning system
Fear conditioning is a behavioural paradigm in which organisms learn to predict aversive events. It is a form of learning in which an aversive stimulus (e.g. an electrical shock) is associated with a particular neutral context or a cue, resulting in the expression of fear responses to the originally neutral stimulus or context.
The TSE Fear Conditioning System is a widely used and established system for studying contextual cued fear learning, retention and extinction in mice and rats. The animal associates a given cue with an electric shock. Alternatively for context conditioning, only an electric shock can be given in the box. During a subsequent retention trial the animal is tested for its natural fear response to the cue and/or context. The fear conditioning software allows the free definition of trace and delay fear conditioning experimental designs. The user-defined sequence of stimuli is applied in 4 measuring stations that are controlled by a single PC. The comprehensive graphical and numerical evaluation of the animal's fear response includes calculation of freezing frequency and duration, activity, hyperactivity and hyperactivity times, rearing events, average speed and % area explored.
The TSE Fear Conditioning System features high-resolution light-beam frames for ultra-precise movement detection in 3 dimensions – up to 100 Hz sampling rate, free definition of experimental designs, context adjustments of visual, auditory and tactile cues, optional computer-control of sound and noise amplitude and sine frequency, and ultra-sound loudspeekers for the evaluation of panic responses in rats.
The TSE Fear Conditioning System is an integral part of the highly flexible Multi Conditioning System.
The active avoidance task provides a convenient method to assess associative learning and memory. It is designed to test the ability of the mouse to avoid an aversive event by learning to perform a specific behaviour in response to a stimulus cue.
The active avoidance task is a fear-motivated associative avoidance test based on electric current as a source of punishment. In this task the mouse has to learn to predict the occurrence of an aversive event based on the presentation of a specific stimulus, in order to avoid the aversive event by actively moving to a different compartment. The measures recorded, number of avoidances (the mouse crossing to the other compartment during the stimulus signal), number of non-responses (the mouse failing to cross to the other compartment during the trial), response latency (latency to avoid or escape), serve as an index of learning and allows memory to be assessed.
The TSE Active Avoidance system is a fully computerized avoidance conditioning system. A variety of compartment dividers are available. Light-beam frames with variable distances for several species monitor the animal’s movements and location. Many parameters are easily adjustable, including habituation, time to shock, shock length, maximum duration and inter-stimulus interval and shock parameters. The resulting data table lists for example conditioned, unconditioned and inter-stimulus transfers and mean reaction times. Distance traveled is presented as a measure of locomotor activity.
The passive avoidance task is a fear-aggravated test used to evaluate learning and memory in rodent models of CNS disorders. In this test, subjects learn to avoid an environment in which an aversive stimulus (such as an electric shock to the feet) was previously delivered.
In this test, animals can freely explore the light and dark compartments of the chamber and a mild foot shock is delivered in one side of the compartment. Animals eventually learn to associate certain properties of the chamber with the foot shock. The latency to pass the gate in order to avoid the stimulus is used as an indicator of learning and memory.
The active and passive avoidance paradigms are also an integral part of the highly flexible Multi Conditioning System by TSE.
Morris water maze with Atlantis platform
The Morris water maze is a widely used behavioural test for measuring spatial learning and memory in rodents.
In the typical set-up, the rodent is placed into the pool, filled with opaque water and containing an escape platform hidden a few millimeters below the water surface. Initially the animal is allowed several training sessions to find the hidden platform. In the final trial, the latency to find the platform is recorded. Different visual cues are placed around the outer walls surrounding the pool to aid the animal in navigation. In the University of Tartu, the hidden on-demand escape platform by Med Associates Inc can freely be set to be controlled by EthoVision XT by Noldus Information Technology. For example, the hydraulic platform can be elevated by the computer program after a certain period of time or when the test subject enters the platform’s proximity. Additionally, EthoVision XT is used to automatically score the behaviour from the video files of the animal inside the pool.
The water maze paradigm can be used both in order to screen for genotype differences and to study pharmacological effects in research animals. University of Tartu is equipped with various sizes of Morris water maze pools, making it possible to conduct research on mice and rats.