Developmental 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.

Laboratory-Based

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.

Clinical Trials

Cognitive function can be assessed in pet animals using a neuropsychological assessment protocol. Cognitive function is also evaluated using questionnaires in which owners are asked a battery of questions about their pet's behavior. These typically include questions about alterations in: alertness, sleep, general activity, house soiling, and interactions between pets and/or conspecifics.

Cognitive function measure using different protocols
The above data was collected using a version of the cognitive test protocol that was modified to allow testing of companion animals in veterinary clinics. Performance in pets showed a similar profile across tests to that seen in laboratory animals.

Setting up a cognitive assessment trial is complex and should ideally include both neuropsychological task performance, to help establish level of cognitive ability, and questionnaire data to determine whether signs associated with cognitive ability have declined over time.

Brain Imaging

The brain can be imaged in a variety of different ways, the choice of imaging modality depending on the research question being answered. Magnetic Resonance Imaging is a very versatile modality that can provide structural and functional data with new developments allowing increasingly complex analyses. Magnetic resonance spectroscopy provides a measure of brain chemistry. Computed Tomography provides more basic structural data, but a strength of CT is the ability to obtain contrast based regional blood flow and blood volume data. Positron Emission Tomography can provide exquisite quantitative data on the distribution of radiolabled compounds. These can be standard labeled compounds such as glucose or dopamine or custom labeling of test compounds can be developed. These images are routinely co-registered to CT images for precise anatomical location of the regions of uptake of the radiopharmaceutical.

Brain imaging data is well correlated with cognitive function in several species. CanCog can provide cognitive testing services to support imaging data in several species.

Structural Brain Imaging

    • MRI or CT to demonstrate structural changes in response to interventions
    • T1, T2. PD sequences
    • Diffusion Tensor Imaging to evaluate changes in myelination
    • Quantitative and qualitative assessment of morphological features or regions of interest by image processing
    T1 Weighted
  • Diffusion tensor imaging graph
    Diffusion Tensor Imaging data showing increasing fractional anisotropy in the frontal lobe, implying increasing myelination with increasing age in young beagle dogs.
  • Graph showing performance on the landmark task
    Data indicating performance on the landmark allocentric learning improves with increased myelination in one year old beagle dogs.

Functional Brain Imaging

  • Dynamic contrast perfusion to assess blood brain barrier permeability and regional cerebral blood flow using either MRI or CT
  • PET/CT imaging with additional coregistration to MRI images if required to quantify glucose uptake
  • Imaging of brain tissues using standard PET radiopharmaceuticals eg F-18 DOPA
  • Imaging of brain tissues with custom developed radiopharmaceuticals linked to specific naturally occurring brain chemicals or novel compounds
18FDG

Magnetic Resonance Spectroscopy

  • Graph showing brain chemistry changes in response to therapeutics
    Quantification of changes in brain chemistry associated with the development and decline of neural function in response to therapeutics
  • Bar chart of MRS data showing changes in brain metabolites
    Magnetic resonance spectroscopy data showing changes in brain metabolites associated with brain development in growing beagles, including markers of neuronal health. Effects of therapeutics can be assessed in attenuating or improving brain development.
  • Bar chart showing changes in concentration of brain metabolites
    Data showing change in concentration of brain metabolites in 10 year old compared to 2 year old beagle dogs

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.

Actiwatch

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