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Collars risk causing neck injuries in dogs, study shows

Posted on May 22, 2020 | 1 comment

A study led by a canine scientist at Nottingham Trent University looked at the potential impact of pulling on the lead and the related pressure on the neck, using a variety of of collar-types and styles.

Young Woman Walks Her Dog In California Park

The collars and a slip lead were tested on a canine cylinder neck model with a pressure sensor.

A range of forces were applied to the lead representing different interactions—a firm pull (40 Newtons) strong pull (70N) and a jerk (141N) – with the contact area of the collar and the pressure on the neck being recorded.

The study, which also involved the University of Nottingham, found that with all the collar types and styles tested—even those that were padded or had a wide fitting—the pressure exerted on the model neck would be sufficient to risk injury to the dog.

No single collar tested provided a pressure considered low enough to reduce the risk of injury when pulling on the lead, they found.

Lead jerks on the collar may occur when dogs on extendable leads abruptly come to a stop, when a dog lunges on a lead, or is ‘corrected’ by the handler.

The researchers argue that as all collar types will pose some risk, dogs should be trained to walk on a loose lead without pulling, or walked using a harness which applies no pressure to the neck.

“All types of dog collar have the potential to cause harm when the dog pulls on the lead,” said Dr. Anne Carter, a researcher in Nottingham Trent University’s School of Animal, Rural and Environmental Sciences.

She said: “While collars provide a means to identify a dog or demonstrate ownership, they are also frequently used as a connection between handler and dog and to facilitate control, restraint or movement.

“Even the ‘best’ type of collar is putting too much pressure on the dog’s neck if they pull on the lead and this is risking injury. We suggest that collars should be used to display ID tags and dogs should be walked on a harness or loose lead that avoids any pressure on the neck.

“It is not recommended that collars be used as a means of control for any dogs that may pull on the lead.”

Study co-author Dr. Amanda Roshier, from the School of Veterinary Medicine and Science, University of Nottingham, said: “Using sophisticated engineering tools, we simulated collar pressures that dogs may be exposed to on the lead and how this varies with different collar models, and the force exerted by a handler. Our tests aimed to give practical insight into how the choice of collar and its use impacts the welfare of dogs.”

Rachel Casey, Director for Canine Behaviour and Research at Dogs Trust, said: “It’s a common problem for owners that their dog pulls on the lead, when excited to get out on a walk. The findings of this research highlight the extent to which all collars exert pressure on the sensitive tissues of dogs’ necks when there is tension on the lead. It is for this reason that we recommend that owners attach a lead to a well fitted harness—particularly if their dog is likely to pull on the lead during a walk or if they use a long line during walks.

“Walks are also made more pleasurable for pet and owner if dogs are taught to walk calmly on a loose lead. Taking a bit of time to teach your dog that he or she can get to the park without pulling, will save a lifetime of pulled arms as well as avoiding possible injury to your dog. We have a range of resources available online on how to teach your dog to walk on a loose lead using a reward-based approach.”

The study was undertaken at the Wolfson Labs, in the Faculty of Engineering with support from bioengineer Professor Donal McNally, also of the University of Nottingham.

The research is reported in the journal Vet Record.

Source: Nottingham Trent University

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Tagged collars, neck injury, Nottingham Trent University, physics

A close up look at how our dogs drink…

Posted on December 5, 2014 | Leave a comment

The field of fluid dynamics explains how our dogs drink and why they splash and slop more than cats…

The drinking mechanism of a dog is videotaped from three different angles (A, B, and C). The curved tongue is rapidly withdrawn and a water column is formed underneath. A physical experiment is designed to understand and characterize the underlying fluid mechanics. Photo by: Sean Gart and Sunghwan (Sunny) Jung/Virginia Tech

By studying the drinking habits of various dog breeds and sizes, a group of researchers at Virginia Tech and Purdue University has recently identified and modeled the fluid dynamics at play when dogs drink water.

“Three years ago, we studied how cats drink,” said Sunny Jung, an assistant professor at Virginia Tech. Jung’s research focuses include biofluid mechanics and the nonlinear interactions between soft bodies and surrounding fluids. His current project is sponsored by the National Science Foundation’s Physics of Living Systems program. “I was curious about how dogs drink, because cats and dogs are everywhere.”

As members of the order Carnivora, cats and dogs have incomplete cheeks, which allow them to open their mouths wide to deliver killing blows. But what makes pack hunting possible also makes suction drinking impossible. Unable to seal their cheeks completely, there is no way for a dog to suck up water. Conversely, humans have “complete” cheeks, and we drink by creating negative pressure, allowing us to suck water into our mouths and down our throats.

Cats, too, lack suction, and they compensate by drinking via a two-part “water entry-and-exit” process. This consists of a plunging and a pulling phase, in which a cat gently places its tongue on the water’s surface and then rapidly withdraws it, creating a column of water underneath the cat’s retracting tongue.

“When we started this project, we thought that dogs drink similarly to cats,” Jung said. “But it turns out that it’s different, because dogs smash their tongues on the water surface — they make lots of splashing — but a cat never does that.”

When dogs withdraw their tongue from water, they create a significant amount of acceleration — roughly five times that of gravity — that creates the water columns, which feed up into their mouths. To model this, Jung placed cameras under the surface of a water trough to map the total surface area of the dogs’ tongues that splashed down when drinking.

The researchers found that heavier dogs drink water with the larger wetted area of the tongue. This indicates that an allometric relationship exists between water contact area of the dog’s tongue and body weight – thus the volume of water a dog’s tongue can move increases exponentially relative to their body size.

In order to better understand how the physiology works, Jung and his colleagues could only go so far by watching dogs drink. They had to have the ability to alter the parameters and see how they affected this ability, and since they could not actually alter a dog in any way, they turned to models of the dog’s tongue and mouth. “We needed to make some kind of physical system,” Jung said.

For their model, Jung and his colleagues used glass tubes to simulate a dog’s tongue. This allowed them to mimic the acceleration and column formation during the exit process. They then measured the volume of water withdrawn. They found that the column of water pinches off and detaches from the water bath primarily due to gravity. Dogs are smart enough to close their mouth just before the water column collapses back to the bath.

Source: Newswise media release