Assessing Cognition, Memory, Pain, and Sensorimotor function.
Neurological diseases often result in a combination of motor and cognitive deficits. Thus, behavioral assessments in conjunction with physiological readouts offer a broader understanding of the basic biological mechanism of disease and cognitive impairment, highly relevant to therapeutic developments. The following are behavior assessments that are added to studies.
Pain Behavior
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Von Frey
Von Frey is used to assess allodynia in animals. A monofilament is applied to the hind paw until the rodent exhibits nocifensive behavior (paw withdrawal, licking etc).
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Dynamic Weight Bearing
The dynamic weight-bearing test (DWB) is used for assessing the distribution of the pressure exerted by each paw. Unlike the static weight-bearing test (SWB), which is carried out on restrained animals only analyzing the hind paws pressure, the DWB test is performed on free moving rats or mice (hence the term “dynamic”). Thus, each paw pressure can be analyzed during static position periods, while avoiding stress accumulation.
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Thermal
Thermal tests are used to assess heat-evoked pain behaviors. Tests include tail-flick, hot plate test, and Hargraeves test.
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Cold Test
Cold tests are used to assess pain behaviors. These tests include the cold plate, acetone test, and dry ice test.
Balance and Coordination
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Rotarod Test
Animals are placed on a rotating rod and latency to fall and rotations per minute are recorded.
Species: Mice, Rats
Uses: Coordination, balance and motor learning. Endurance
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Paw Placement/Cylinder Test
The animals are placed into an open-top, clear plastic cylinder. Forelimb (front paw) placement against the wall while rearing (e.g. for support) is recorded.
Species: Mice, Rats
Uses: Evaluation of locomotor asymmetry
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Balance Beam/Catwalk Test
Fine motor coordination and balance can be assessed by the beam walking assay. The goal of this test is for the mouse to stay upright and walk across an elevated narrow beam to a safe platform.
Species: Mice
Uses: Motor balance. motor function, balance, and fine motor function
Learning and Cognition
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Morris Water Maze Test
Animals are placed into a pool containing a hidden platform 1 cm below the surface. The time to find the hidden platform (e.g. to learn and/or remember) is recorded.
Species: Mice, Rats
Uses: Spatial learning and memory assessment. Particularly useful in hippocampal injury (e.g. 4VO cerebral ischemia models
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Tail Suspension
Mice are suspended by their tail for 6 min for assessment of immobility versus mobility time.
Species: Mice, Rats
Uses: Depression/behavioral despair reaction to an inescapable and stressful context
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Novel Object Recognition
The Novel Object Recognition test is used to assess recognition and memory. Two objects are presented to rodents in the initial test. One object is then replaced with a new object and the time the rodent explores the new object is used as an assessment of recognition memory.
Sensory and Motor Function
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Paw Adhesive Removal
Two adhesive strips are applied to each animal forepaw. Time for first reaction to the adhesive in each paw (contact time) and the time for adhesive removal (removal time) is recorded.
Species: Mice, Rats
Uses: Sensory functions, sensory neglect and motor functions (left and right side).
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Tail Suspension
Mice are suspended by their tail for 6 min for assessment of immobility versus mobility time.
Species: Mice, Rats
Uses: Depression/behavioral despair reaction to an inescapable and stressful context
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Grip Test
Animals are gently held by the tail and placed over the top of a grid such that their front paws can grip the strength meter. Animals are then pulled backwards until they can no longer grip the strength meter and exerted force is recorded.
Uses: Quantification of muscular strength
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Open Field
Measures unfettered animal movement within an inescapable enclosure.
Species: Mice, Rats, Pigs
Uses: Pain, motor function, lethargy, hyperactivity, and anxiety related behavior
Anxiety and Stress
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Open Field Test
Measures unfettered animal movement within an inescapable enclosure.
Species: Mice, Rats, Pigs
Uses: Pain, lethargy, hyperactivity, and anxiety related behavior
What can be learned from Open Field (OFT)?
While technically simple to perform, OFT is a highly versatile, informative technique for assessment of general activity levels, gross locomotor activity, and exploration habits. Additionally, enclosure may be modified to examine learning and memory functions (e.g. Novel Object Recognition).
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Tail Suspension
Rodents are suspended by their tail for 6 min for assessment of immobility versus mobility time.
Species: Mice, Rats
Uses: Depression/behavioral despair reaction to an inescapable and stressful context
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Forced Swim Test
Animals are placed in a cylinder of warm water to a depth exceeding the length of the animal. Following an initial period of acclimation, behavioral responses are assessed.
Species: Mice
Uses: Depression/behavioral despair reaction to an inescapable and stressful context
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Elevated Plus maze
Animals are placed at the junction of a cross-shaped maze consisting of 2 open arms and 2 closed arms. Unfettered movemet between the 4 arms is monitored. Both number of entries and time spent in the open arms is analyzed.
Species: Mice
Uses: Open space-induced anxiety
Spontaneous Behavior Score in Pigs.
Assessment of spontaneous behavior requires observation of the social and individual behavior of pigs in the open pen. The scoring method used is based on a numerical rating scale (NRS) of multifactorial criteria and is modified from the method described by Reyes et al. (2002). The behavior score is divided into two distinct categories: (1) solitary performance and (2) social behavior.