Aged Dog Models

Cognitive Assessment

The cognitive abilities of companion animals include learning, memory, attention and communication and, as in humans, can profoundly affect their quality of life. In young animals, cognitive assessment procedures can be used to predict success of dogs used in high level training programs. Cognitive assessment is particularly important in evaluating older animals. Aged dogs and cats are prone to develop a form of dementia, cognitive dysfunction syndrome, which includes, but is not limited to, impaired cognitive skills.

We have developed a battery of laboratory-based cognitive tests that can provide a general profile of cognitive ability in dogs and cats. All of the tasks require the subject to make a specific response, and if correct the animal is provided with a highly palatable food reward. In most cases, cat tests are the same as those used in dogs. Furthermore, cats, like dogs show age dependent decline in cognition, and clinically a percentage develop cognitive dysfunction syndrome.

Complex Learning and Memory

The delayed-non-matching-to-position task (DNMP) has been developed to assess both learning ability and memory. The task requires an animal to learn a general rule: to remember the location of an object and to subsequently respond to the object at a different location (the non-matching location). This is a particularly useful task because performance varies directly with age: young dogs learn the task rapidly; older dogs learn more slowly, and very old dogs may be unable to learn even with extensive training. Memory can be assessed by varying the time interval between the first presentation and the test trial. The longer the time interval (delay) the more poorly the animals perform.

  • Graph showing errors on the DNMP task
    Errors on the DNMP increase with age and significant deficits are seen as early as six years of age in dogs.
  • Graph showing accuracy in learning a DNMP task as a function of age
    Accuracy in learning a DNMP task in cats as a function of age. The adult cats were between 3 and 4 years of age; the old cats ranged from 7 to 9 and the senior animals were > 11.

Behaviour & Activity

We have developed several behavioural assays for the assessment of activity and movement which can be used to evaluate disorders such as musculoskeletal disease. These include:

  • Assessment of activity using Actiwatch monitors in both the laboratory and clinical setting
  • The open field measure of activity
  • Measures of agility including the reaching test and the t-maze test

Behavioral Assays

Behavioral assays that do not entail learning and memory (i.e. non-cognitive) can be used to study agility and movement. We can provide the following in dogs and cats:

Open Field Activity

The standard canine and feline open field tests entail placing the animal in the open field arena and allowing the subject to freely explore the room over a fixed period of time. Movement is recorded using a video tracking system and trained personnel record behaviors of interest.


The actiwatch is a monitoring device, sensitive to movement that can be placed inside a specially designed case and attached to a collar placed around an dogs neck. The actiwatch allows continual monitoring of general activity and can be used to both assess arousing effect of an NCE and also to monitor 24 hour activity and activity rhythms.

Motor Function

We utilize the following tests in order to assess motor functions in dogs:

  • Agility - T-Maze
  • Reaching
  • Staircase test