Pit bulls, mixed breed dogs most likely to bite - study

One particular type of dog has been singled out as more likely to bite young children than any other in a new study.

It probably won't come as a surprise, but it's the pit bull.

But owners of the controversial breed think the researchers are barking up the wrong tree.  

Researchers in Ohio studied years of dog bite data and found pit bulls not only did more biting than any other type, they also did the most damage.

"The purpose of this study was to evaluate dog bites in children, and we specifically looked at how breed relates to bite frequency and bite severity," said Garth Essig of the Ohio State Wexner Medical Center, who led the study.

Dog bites were graded on the size of the wounds they inflicted, how much tissue they damaged and bone fractures.

"We see everything from simple lacerations to injuries in which there's significant tissue loss that needs grafting or other reconstructive surgery," said study co-author Charles Elmaraghy.

In around 60 percent of cases, the exact breed couldn't be determined, or it was of mixed heritage - but there was a common factor.

"We looked at additional factors that may help predict bite tendency when breed is unknown like weight and head shape," said Dr Essig.

They determined large dogs - over 30kg - with flat, wide faces were just as dangerous as pit bulls.

Around 20 percent of dog bite victims require medical care, they said, with the vast majority in the US being children aged five to nine. A New Zealand study published in 2014 which looked at a decade's worth of dog attack data found pre-schoolers suffered the highest injury rate.

"The physical and psychological consequence from a dog bite can't be overstated," said Dr Essig.

But dog lovers often argue it's not the dog's fault - it's the owners that are the problem.

The New Zealand American Pit Bull Terrier Association told Newshub breeds are "irrelevant" when it comes to attacks.

American pit bull.
American pit bull. Photo credit: Getty

"We do not accept that pit bulls or their mixes are the worst offenders and with good reason," said spokesperson Karen Batchelor.

"In general, mixed breed dogs have been found to top the list of offenders worldwide simply because they are the most common type of dog in the general population. Pedigree dogs appear according to their popularity on the day and according to a water-tight identification."

She studies have shown identifying a dog is unreliable about three-quarters of the time.

"There is a lot of ground yet to be covered in the matter of the demonisation of the American pit bull terrier, but suffice it to say for now that dog attacks on people occur for well-researched and documented reasons and that knowledge has been out there, peer-reviewed and published in respected journals, for many decades."

Batchelor said pit bulls are actually the least likely to bite a human "as a direct result of their dog fighting history".

"A pit dog who bites his handler is a dead pit dog."

Many councils in New Zealand have restrictions on certain breeds and types of dog considered menacing and/or dangerous. They typically include American pit bull terriers, of which around 2700 pure breds are registered at present - down from 3000 in 2014. There are about 560,000 registered dogs of all breeds in New Zealand.

Last year there were more than 14,000 ACC claims for dog-related injuries, with around $3.5 million paid out. The numbers have been rising since 2011, much faster than the rate of dog ownership.

The latest study was published in the International Journal of Pediatric Otorhinolaryngology.