The investigation was carried out by researchers at Spain?s School of Veterinary Medicine at the Autonomous University of Barcelona.

Researchers studied data relating to more than 1,000 dog aggression cases logged between 1998 and 2006.

Of those cases, English cocker spaniels were ranked the worst, followed by Rottweilers, boxers, Yorkshire terriers and German shepherd dogs.

Let us know what you think about this!

  • richard vary

    I agree with Mr. Don Fields’ experienced and thoughtful comment. My British Cocker Spaniel is a wonderful upland bird flusher and a good companion.

  • Keith Christmas

    Sounds complete nonsense – where on earth do they get this research from? Mine is as gentle and soft as they get, unless he’s hunting, then he’s formidable.

  • Amanda

    Yes I agree Cocker Spaniels can be aggressive, but it needs to be remembered that these study results have been conducted using the show cockers NOT the working cockers.

  • Hayley

    I have a 2yr old cocker spaniel that we have had since a pup. He can be agressive with his food, he recently has become very possesive over his bones. He doesn’t even have to be eating it, just laid with it and if u stroke him u get a growl, if u go near the bone it gets even loader and more intense. our other dog has never done this! she growls in play but never seriously – she is a patterdale terrier. He can however come upto you with the bone in his mouth wagging his tail and sticking the bone in your face, at which point he has no problem with you removing it from his mouth!!!… this confuses me. how can he care one minute and not the other. He isnt however agressive with anything else, not his food bowl, other dogs, toys etc… just the bone!!

  • Joanne small

    seeing your article about cocker spaniels being aggressive I think it is a load of bull!

  • richard vary

    My experience is ancedotal experience of over fifty years with dogs and not part of a study. I would not classify cocker spaniels as an aggressive breed, but just the opposite.
    I am curious as to how the investigation was conducted and what factors were determinative.
    My daughter’s current cocker spaniel is a delightful, energetic, intelligent hunter with an abundance of intelligence and does not show aggressive tendencies.

  • American Cocker

    I Do believe this to be true, My Cocker will charge at anybody and is very possessive. I use her to chase Deer in Greenville, NC, and she definitely shows the Beagles who is in charge.

  • Katie

    My 14 month old Working cocker Spaniel is the most gentle thing on most occasion,he will pick things up gently with his mouth, he is exceptionally bright. The only exception is if you put you hand anywhere near his food/mouth while hes eating (fool hardy on my boyfriends part!!) I wouldnt say its down to his breed more so like all humans/Dogs/animals he has his own quirks and off days! I had a rescue Jack Russel for years and i could tell some very gruesome stories that make my Cocker look like a saint!!

  • darren

    when i was a kid my dad rescued a Cocker spaniel from a horrible man who was mistreating it he was punching and kicking it ,we had to keep it in the shed because as soon as it herd a mans voice it wet it self but it was still one the most non aggressive friendly dog we’ve ever had
    i believe dogs are not borne aggressive people make them aggressive the same as guns don’t kill people people kill people

  • jack monaghan

    I wouldn’t have thought they’d be the MOST aggressive, but cockers can contract rage syndrom. Could that be the case?
    Also, there’s one thing i dont get; Boxers! eh?
    It’s not like i own one, but by all the research i’ve done, there supposed to be lovely dogs. plus, what about pitbulls, presa canarios,etc?

  • katie Sercombe

    I have four cocker spaniels, not one has ever shown aggression in anyway to any person or other animal.

  • JT

    We own a little cocker (1/2 show & 1/2 working) and on the whole he’s the most adorable dog, affectionate, full of character and wanting to please when it suits!
    But we have spent the first 8 months of our lives together battling his aggressive nature. Both my partner and I have scars on arms from where he has bitten us and can remember where the bruises were. In fact some of my colleagues asked me if my partner was abusing me.
    There have been dogs before in the family and when I spoke to the breeder about his nature she told me to shake him firmly and that his mother could be quite vicious when she wanted.
    So we’ve gone down the route of hand feeding him and when all else fails bitter apple spray but there are still times when he’s not getting his own way he will bite.
    In essence any dog can be aggressive even those you would never think of.

  • Don Fields

    I am a retired HMP Police dog handler and trainer with over 30 yrs experience and can tell you that blanket statements like those on “cockers” are not helpful and that any dog has the potential to be or become aggressive,for a number of reasons ie ill treatment, fear, poor handling or breeding, like humans we all have differing temperaments and react differently in situations,since retiring I have a young cocker and she is very placid, boistrous yes but gentle in nature, in my working life I came across many different breeds each had the odd bad apple but I can honestly say no breed stands out and I believe as with any survey it depends who what when and where information is gathered!! as I said before any dog can and will show aggression given the circumstances and these are in most cases handler/owner caused, during my many years shooting I have never come across a working cocker that could be remotely described as aggressive.
    Don Fields ISM PSM QGJM

  • Cliff Whitney

    Utter rubush,dant tell every one or hoodies will have them
    Cliff Whitney

  • JEFF POWELL

    ALL THE TIME THAT I HAVE OWNED COCKERS I HAVE NEVER HAD ANY ANGER PROBLEMS. I ALSO THINK THAT IF YOU TRAIN YOUR DOG PROPERLY THEY ARE LESS LIKELY TO BE AGGRESSIVE.