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 fea…

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.



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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 co…