Companion Animal Psychology

New research shows that overweight and obesity in dogs is a One Health issue, and neutering male dogs is a risk factor



By Zazie Todd, PhD

When dogs are overweight or obese, it can affect their health and even shorten their lifespan significantly. So understanding the causes is important. New research from Denmark on the risk factors for dogs being heavy or obese raises questions about the role of the owner and the effects of spay/neuter surgery.

The study, published in Preventive Veterinary Medicine, finds that neutering increases the risk of being heavy or obese in male dogs, but not in female dogs because they are already at higher risk. The results also suggest we need to think of overweight and obesity in dogs as a One Health issue, because the health of people and their pets is interconnected.

Dr. Charlotte Reinhard Bjørnvad, first author of the study, told me in an email,
“The finding that neutering triples the risk of developing obesity specifically in male dogs is important. It…

Tiger cubs in captivity, just how smart crows are, and dogs that commit stufficide... the latest Companion Animal Psychology news.



Wag publication date Exciting news! My book, Wag: The Science of Making Your Dog Happy now has a publication date: 10th March 2020.

I met with my publisher’s marketing team last week at their offices in Railtown, Vancouver. It was great to meet them and talk about marketing and publicity for the book. I saw an advance reader copy which looks *gorgeous* as they designed a beautiful cover, but I wasn't allowed to bring one home. I am going to be very busy over the next six months working to tell people about Wag. I can’t wait to share my book with you!

If you're a media person and would like to receive an ARC, you can find details here.

My favourites this month “Our search for medieval guide dogs leads us to a Book of Hours (a popular type of medieval prayer book)” A fascinating account (complete with pictures of mediaeval art) of guide dogs in media…

Bacteria in the anal glands of a cat are responsible for chemical signalling via poop, study shows.


By Zazie Todd, PhD

Many species of carnivore use chemical signals in faeces as a way of communicating. Stinky secretions from the anal sacs, on each side of the anus, provide odours in poop that are used for chemical signals and scent marking.

Wolves and spotted hyenas use these to mark territory; it is believed domestic cats do too, although this behaviour is not fully understood. Striped hyenas, spotted hyenas, and ferrets use these chemical signals to recognize other individuals. Skunks and honey badgers even use these secretions as a form of defence, and if you’ve ever met a dog that’s been skunked, you know how bad that is. Now new research from UC Davis, published in PLOS One, sheds light on how the smells in these secretions are made in cats.

The anal sac secretions from domestic cats convey information about the sex of the cat and its reproductive state, and can also be used to …

Going to puppy class has benefits for later dog behaviour, study shows.


By Zazie Todd, PhD.

Puppies have a sensitive period for socialization from 3 until about 12-14 weeks, during which it is especially important to have a wide range of positive experiences. Many people take their puppy to puppy class during this time, but some people wonder, “Is puppy class worth it?” A new study published in the Journal of Veterinary Behaviour finds several advantages for dogs that attended puppy class when younger compared to those who didn’t.

The study, by Dr. Ángela González-Martínez (Santiago de Compostela University) et al., took place in Spain and compared dogs who had completed puppy class one year earlier to those of the same age who had not taken a puppy class. The dogs were assessed using a questionnaire called the C-BARQ which was completed by their owner.

The results showed that dogs who attended puppy class were more highly rated as trainable, and were less likely to have non-social fe…

The benefits of nose work for ‘naughty’ and ‘reactive’ dogs
Guest post by Luisa Dormer and Sienna Taylor.


For many people, taking their dog to training classes is an enjoyable experience that helps to make the bond between them even stronger. For a number of dog owners, however, the thought of taking part in such activities can fill them with dread due to their dog’s ‘naughty’ behaviour. Examples of behaviours that are considered problematic include being destructive, hyperactive, straying and showing aggression towards other dogs (Wells and Hepper, 2000).

Dogs that are considered hyperactive, or have a tendency to stray or run off on walks, may have strong hunt, play and prey drives. Hunt and prey drives can be defined as the dog’s innate desire to pursue, capture and kill prey, whereas a play drive is the innate desire of a dog to want to play. Dogs that display behaviour such as barking, growling, snapping, biting and lunging when they see other dogs can be referred to as ‘reactive’…

" a treat for dog lovers, but also essential reading for anyone interested in our relationship with nature, and what that says about us.” - Ed Yong.



This month's choice for the Animal Book Club is Our Dogs, Ourselves: The Story of a Singular Bond by Alexandra Horowitz.

From the book description,
"From Alexandra Horowitz, #1 New York Times bestselling author of Inside of a Dog, an eye-opening, informative, and wholly entertaining examination and celebration of the human-canine relationship for the curious dog owner and science-lover alike.  We keep dogs and are kept by them. We love dogs and (we assume) we are loved by them. We buy them sweaters, toys, shoes; we are concerned with their social lives, their food, and their health. The story of humans and dogs is thousands of years old but is far from understood. In Our Dogs, Ourselves, Alexandra Horowitz explores all aspects of this unique and complex interspecies pairing.  As Horowitz considers the current culture of dogd…

Fear Free has released free training for staff and volunteers in animal shelters.



Fear Free, known for its revolutionary approach to reduce fear, anxiety, and stress for pets at the veterinarian, has just launched the Fear Free Shelter Program. The program provides free online training for anyone who works or volunteers at an animal shelter that will teach them how to reduce stress for the animals and provide them with enrichment.

The program covers all stages from the intake of animals through to adoption. It also provides resources that adopters and foster homes can use to promote the emotional well-being of the pets in their care and ease the transition to a new environment.

The program was created by lead author Dr. Brenda Griffin, along with three veterinary behaviourists who all have experience in shelter medicine. Griffin is an adjunct associate professor of shelter medicine at the University of Florida, and is also an instructor at the University of Georgia.

“We created the Fea…

A recent court case in Nova Scotia considered the role of emotional suffering in an animal cruelty case. It's a first for Nova Scotia, but not the first time courts in Canada have considered emotional  harm as part of an animal cruelty case.

Read more about the science behind this in the role of emotional harm in animal cruelty at my Psychology Today blog, Fellow Creatures.

Photo: Lynette C/Pixabay

The importance of play, chickens as domesticated animals, and beautiful cat photos – this month’s news.



My favourites this month “It took two weeks for her to start greeting friends normally (people she knows and loves). Before that, when they would come, she would run up to my bed and hide.” An important post from Eileen Anderson with a story from a dog owner about what happened when a trainer used a shock collar on her dog, and commentary from Eileen about the issues with shock collars and an unregulated industry.

“Play is so important for normal development that it takes a lot to deprive an animal of play and play deprived animals are a mess.” Giz asks, do animals work out, with lots of great comments about play. Compiled by Daniel Koltz.

Do cats hold a grudge?Dr. Mikel Delgado looks at two studies of the effects of different handling techniques on cats.

Traveling with your dog. Reviews.com interviews Suzanne Bryner of Lucky Fido Dog Training, and you'll find lots of great tips f…

Over at my Psychology Today blog, Fellow Creatures, I have a new post on animal hoarding.


It looks at a study of a new, integrated approach taken in Wake County, North Carolina, where multiple agencies now work together on animal hoarding cases. Animal hoarding is a mental health issue recognized in the DSM-5, and many hoarders simply start again once their animals are taken away.

The new approach includes guidelines on how many animals they can keep and the care they must provide. You can read the post, taking an integrated approach to animal hoarding.

Join over 2,500 animal lovers and subscribe to Companion Animal Psychology to make sure you never miss a post.


By Zazie Todd, PhD.

My pick of the books to read this summer, from books about animals to the latest fiction and nonfiction from Canada and elsewhere.



By Zazie Todd, PhD

It’s beautiful weather here, and time for pottering about in the garden and sitting with a book. These are the books I’ve read or am reading this summer.

You can find them all in my Amazon store: https://www.amazon.com/shop/animalbookclub


Our Dogs, Ourselves: The Story of a Singular Bond by Alexandra Horowitz
In Our Dogs, Ourselves, Horowitz takes a fascinating look at the human-dog relationship, ambiguities and all. She’s been listening in on the ways people talk to their dogs and details the fun things that happen in a dog cognition lab. In reflecting on historical changes in breeds, such as the increasingly flat faces of some dogs, she urges dog owners to do better. And the relative risks and benefits of spay/neuter surgery may not be what you think. This is a beautiful, thoughtful, and heart-breaking book. Delightful and hard-hitting i…