Introduction
Bite force refers to the amount of pressure, measured in pounds per square inch (PSI), that a dog can generate through their jaws and teeth. It is an indicator of the strength of a dog’s bite and gives insight into the potential damage they could inflict. Understanding bite force is important for evaluating breeds for purposes like police work, guarding, and dog sports. Research has shown large variability in bite force between breeds and even between individual dogs of the same breed due to factors like age, size, and skull structure. Some of the highest bite forces have been measured in breeds like Kangals, mastiffs, and Rottweilers, while smaller dogs tend to have much weaker bites.
This article will provide an overview of research into dog bite forces, discussing how they are measured, breed differences, factors that influence strength, and rankings of the highest bite forces. It will also cover the purpose and safety risks of strong dog bites to provide a comprehensive understanding of this metric in canines.
Measuring Bite Force
There are several devices and methods used to measure the bite force of dogs:
Pinch Gauge: This tool measures bite pressure in pounds per square inch (psi). It is a mechanical device that is placed between the dog’s teeth to get a reading of bite force. Veterinarians may use this to test bite force during examinations. According to one study, pinch gauges gave readings ranging from 220-560 psi for canine teeth and 310-1100 psi for carnassial teeth in dogs (Kim, 2018).
Piezo-resistive Sensors: These electronic devices use pressure sensitive semiconductor material to quantify bite force. Sensors are mounted on a model of a tooth to directly measure the force applied. One study using these sensors found forces ranging from 13-1104 Newtons in dogs (Kim, 2018).
3D Models: CT scans can be used to create 3D models of a dog’s skull and jaw. Software can then simulate the bite force based on jaw muscle measurements and mechanics. This provides an estimate of potential bite force (Kim, 2018).
In most cases, readings are taken when dogs bite down on sensors mounted on hard rubber bite bars. Multiple measurements are taken and averaged to account for variability. Proper equipment and training is needed to safely and humanely obtain bite force measurements.
Breed Differences
There are significant variations in bite force between different dog breeds. This is due to differences in jaw and skull structure, as well as the original purpose the breed was developed for. For example, breeds like the Kangal that were historically used for guarding livestock have extremely powerful bites up to 734 PSI. Other muscular breeds like the American Bandogge (730 PSI) and Cane Corso (700 PSI) also have very high bite forces (World Animal Foundation).
In comparison, smaller breeds like Chihuahuas and Dachshunds have much weaker bites, usually under 100 PSI. Herding breeds like Collies also tend to have lower bite forces since they were not bred for protection like guard dogs. The difference in jaw strength between breeds is mainly influenced by the dog’s original purpose and body size.
Individual Variation
While there are overall differences in jaw pressure between breeds, there can also be significant variation between individual dogs of the same breed. One study analyzing bite force in pit bulls found substantial variability, with some dogs biting at over 450 psi while others of the same breed bit closer to 250 psi (https://pubmed.ncbi.nlm.nih.gov/32587065/).
This indicates that factors like age, sex, size, individual skull structure, and conditioning of the jaw muscles, likely play a role. So two dogs from the same litter can have pronounced differences in their bite force depending on their specific characteristics. It’s not solely a breed-dependent trait.
Additionally, dogs trained for protection work or other biting sports may be conditioned to have stronger jaw muscles and bite pressure. So the life experience of each dog can alter the natural bite force potential of their breed.
Age and Size
Dog bite force generally correlates with the age and size of the dog. Younger dogs typically have weaker bites due to their smaller muscle mass and jaws that are still developing. As dogs grow into adulthood and their jaws and muscles become stronger, their bite force increases.[1]
Larger dog breeds typically have much stronger bites than smaller breeds. For example, mastiffs and rottweilers have some of the highest bite forces due to their large size and muscular builds. Small breeds like chihuahuas and terriers have relatively low bite forces due to their tiny jaw muscles.[2]
However, bite force is not solely determined by size. Jaw strength, individual temperament, and bite style also contribute. Some small terriers have stronger bites than much larger dogs due to these other factors. Nonetheless, age and size set the general limits for how strong a dog’s bite can potentially become.
Jaw and Skull Structure
The anatomy of a dog’s jaw and skull plays an important role in determining its bite force capacity. According to research, dogs with larger heads and jaws tend to have stronger bite forces (Bite force and its relationship to jaw shape in domestic dogs). This is because they have larger, more powerful jaw muscles attached to the skull that generate greater force.
Some specific aspects of jaw and skull structure that influence bite force include:
- Size of temporalis and masseter muscles – Larger jaw muscles allow for stronger bites.
- Width of skull and jaws – Wider skulls accommodate larger jaw muscles.
- Length of muzzle/snout – Shorter muzzles concentrate force over a smaller area.
- Gape – The maximum opening of the jaws affects how widely dogs can open their mouths to bite.
- Hinge – The temporomandibular joint where the upper and lower jaw connects.
So in summary, dogs like mastiffs and pit bulls with wider skulls, shorter snouts, larger jaw muscles, and wider gapes generally have the strongest bite forces.
Bite Styles
Dogs have different types of bites and grips depending on their breed and purpose. According to dogstodiapers.com, some breeds like beagles, bassets, and coonhounds are more likely to bark than bite with force. If they do bite, they tend to nip rather than deeply grab and hold. Retrieved from lasalvia-law.com, dogs bred for protection like rottweilers and German shepherds often have powerful grips and hold on tenaciously when they bite. Sporting and herding breeds that need to nip but not damage like spaniels and collies deliver quicker biting action but with less force.
The grip and power of the bite is related to the shape and size of the dog’s head and jaws. Broad-headed muscular breeds like mastiffs and Rottweilers have the strongest bite forces and gripping power. Dogs with long snouts and narrow jaws like greyhounds do not have as much bite strength. Overall the force of the bite relates to the dog’s original purpose, with guard dogs and fighting breeds tending to have very strong grips and holding power compared to dogs bred just for companionship.
PSI Rankings
When measuring the strength of a dog’s bite, the standard unit used is pounds per square inch (PSI). Studies have been conducted to determine which dog breeds have the highest PSI ratings.
According to research, here are some of the dog breeds with the highest bite force as measured in PSI:
- Kangal (Turkish breed) – 743 PSI
- American Bandogge – 730 PSI
- Cane Corso – 700 PSI
- Dogue de Bordeaux – 556 PSI
- Tosa Inu – 556 PSI
- English Mastiff – 556 PSI
- Dogo Canario – 540 PSI
- Dogo Argentino – 500 PSI
The Kangal has the strongest dog bite force in the world, measured at 743 PSI. This powerful, Turkish guard dog is used to protect livestock from predators.
Other breeds known for having strong bite force measurements include Pit Bulls, German Shepherds, and Rottweilers. However, the PSI varies widely even within breeds due to differences in age, head structure, and size of each individual dog.
Purpose of Strong Bites
Dogs evolved strong bite forces for several key reasons related to their ancestry and behavioral traits.
One major reason is that dogs are descended from wolves, who needed powerful bites to take down large prey like elk and bison. The ability to deliver incapacitating bites gave wolves an evolutionary advantage when hunting (1).
Additionally, dogs use their bites for self-defense and protection. Guarding and territorial breeds like Kangals and Rottweilers have especially strong bites, which deter potential threats. Their impressive jaw pressure is an asset for police, military, and personal protection work (2).
Dogs also employ their bites during play and disciplinary activities within their pack. Puppies nip each other as they learn bite inhibition. Adult dogs correct unwanted behaviors with a firm muzzle grab. Though bites are rarely intended to seriously harm, a strong jaw gives dogs an advantage in correcting pack mates (3).
Finally, male dogs rely on biting during mating activities. Females will test male suitability by instigating play fights. Males must be able to gently restrain females with their jaws during copulation. As such, breeding viability has likely contributed to the evolution of canine bite strength (4).
In summary, the power behind a dog’s bite force relates directly to its lupine ancestry and serves essential functions for hunting, defense, social order, mating, and play.
Sources:
(1) https://www.countryliving.com/uk/wildlife/dog-breeds/a39699921/dogs-strong-bite-force/
(2) https://a-z-animals.com/blog/dogs-with-the-highest-bite-force/
(3) https://spartacuslawfirm.com/las-vegas-dog-bite-lawyer/strongest-dog-bite-force-the-complete-guide/
(4) https://spartacuslawfirm.com/las-vegas-dog-bite-lawyer/strongest-dog-bite-force-the-complete-guide/
Safety Tips
To avoid dog bites, it’s important to be aware of dog behaviors and warning signs. According to the American Veterinary Medical Association (AVMA), actions that can provoke dogs and lead to bites include:1
- Disturbing a dog while it’s sleeping, eating, chewing, or caring for puppies
- Petting or reaching for a dog without letting it see and sniff you first
- Turning your back on a dog and running past a dog
- Playing aggressively with a dog, like wrestling
Warning signs a dog may bite include growling, snarling, showing teeth, stiffening, staring, and raising hackles. KidsHealth recommends teaching children some basic safety around dogs:2
- Do not approach unfamiliar dogs without an adult present
- Do not run, scream, or wave arms around dogs
- Pet dogs gently and avoid sensitive areas like their face
- Back away slowly if a dog growls or shows signs of aggression
Being aware of proper dog interactions and warning signs can help avoid bites and keep both people and pets safe.