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The CNDM houses 29 marmosets and 11 macaques (updated February 5, 2024)

Non-human primates are genetically closer to humans than rodents and exhibit behaviours closer to humans. Their brain is more evolved than the rodent brain and shares anatomical and chemical characteristics with the human brain which are not encountered in rodents. For instance, a marmoset and a rat are both about 350g, but the marmoset brain is 7 times bigger than a rat brain, even if the two species are approximately the same weight.

The tests performed aim at studying aspects of human health and disease. For example, tests reveal social aspects of behaviour, language, visual perception, memory, and movement, and provide insight into the brain function within each of these paradigms.

NHPs undergo a lengthy acclimatisation period, designed to minimise the stress caused by the studies. During these studies, animals’ behaviour may be observed and rated according to specific scales. Animals may also be administered promising novel therapeutics, or undergo experimental procedures that seek to further our understanding of brain physiology, to assess their potential to treat human diseases.

To gain insight into the human brain in health and disease, it is important to use animals whose brain is as close as possible to humans’. In addition, there are important differences between the metabolism (clearance) of drugs and substances between rodents and primates (including humans). As such, determining the metabolism of drugs in non-human primates enables investigators to optimise the drug administration and dosing schedule in humans, thereby minimising the risk of adverse events to human subjects.

Each procedure or test to be performed needs to be approved by an animal care committee, which includes scientists, veterinarians, animal care technicians and members of the community. During the review process, members of the committee ensure that protocols meet the highest scientific standards, that the number of animals to be used is kept to a minimum, and that all efforts are made to avoid causing any pain to the animals.

Each protocol needs to be renewed on a yearly basis; during the renewal process, members of the committee ensure that experiments conducted during the past year and experiments to be performed in the upcoming year meet the highest scientific and ethical standards.

Lastly, a post-approval monitoring process ensures that the approved studies are conducted with scientific rigour, and in a humane way.

Millions of people are alive today because of the benefits of medical research with animals, and millions more are living longer, . Many of the treatments we take for granted today could not have been possible with animals during the research and development phrase. For example, the polio vaccine, developed in part after testing on animals, has saved millions of lives since scientists discovered it in the 1950s. More recently, the development of the COVID-19 vaccine could not have been possible without animal testing.

Biomedical research requires a multitude of different but complementary models to test hypotheses. Scientists need to study cells, organoids, insects, fish, mice, NHP, and humans, all at varying stages of the discovery process and at varying levels of invasiveness.

Over the past decades, we have witnessed enormous progress in fundamental neuroscience and the biology of neurological diseases through rodent models. However, it is increasingly apparent that the validity of rodent models for neurological disorders is limited, in part because of the sophisticated neural and behavioral manifestation in patients.

For example, social interaction between humans require integrated cognition and comprehension, which are more closely associated with primates than rodents. Non-human primate species, such as common marmosets, possess a high level of cognitive ability and enriched behavioral repertoire, and are closer to humans than rodents in brain structure and circuit connections. non-human primate models, therefore, are urgently needed to bridge the gap between rodent models and human patients. We anticipate that authentic non-human primate models of brain disorders will provide an in-depth neurobiological understanding of pathophysiology and facilitate the development of effective therapies.

In terms of drug development, in the past decades several drugs have failed in high-profile clinical trials for diseases such as Alzheimer’s and Parkinson’s. Some of these drugs were tested in humans because they showed efficacy in rodent models at, in some cases, reversing disease symptoms. However, when advanced to clinical testing directly after rodent studies, severe adverse events occurred in humans, and the efficacy achieved in rodents was not obtained in humans. Such adverse events and lack of efficacy highlight the limitations of rodent models and the potential risks incurred by clinical trial participants when drugs are administered to humans without thorough pre-clinical assessment.

Compared to other types of non-human primates, working with marmosets presents several advantages. Their small size facilitates housing and allows us to keep multiple animals when space is limited. They do not carry pathogens that may be harmful to humans. Their rapid reproductive cycle opens the door to more precisely studying the role of specific genes in certain behaviours and diseases. They exhibit complex behaviours that are close to humans which we need to study.

We hope that research on non-human primates will lead to treatments for various diseases, including Parkinson’s, Alzheimer’s and autism spectrum disorder.

Animals are used in research only when no other adequate methods are available. Researchers at The Neuro use many techniques to study the brain that do not involve animals. Non-invasive cognitive testing on humans, for example, helps us understand basic brain functions that can inform future studies into neurological problems. Other scientists use artificial intelligence and big datasets to find patterns in disease pathology. This can help us understand how diseases such as Alzheimer’s and Parkinson’s progress, and how we can best stop them. Genetic testing using human samples also tells us about the role of genes in neurological disease and how we can target specific gene pathways to treat or prevent diseases.

Animal research in Canada is regulated at the federal level by the . Institutions using animals are held to the same high ethical standards regardless of the species of animal studied.

Animal research has led to many lifesaving and life-extending treatments for a variety of species, including cats, dogs, farm animals, wildlife, and endangered species.

Humans share many biological and physiological characteristics with animals, and so biomedical research with lab animals advances veterinary medicine as well, helping pets and wildlife live longer, happier, and healthier lives.

Dozens of diseases, from cancer to epilepsy, affect both animals and humans. Through research with animals, scientists can develop treatments and therapies that help both people and animals.