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Ask the Veterinarian/Pressure Necrosis


Dr. Dave wrote at 2006-07-15 15:11:56
These collars can cause irritation if worn too tightly, or left on for extended periods. It is incorrect, however, to refer to these sores as burns. A burn is caused by heat, and there is no heat generated by the static shock, even on the highest settings. Obviously anything rubbing against a person's or dog's skin will eventually cause a rash that will get worse the longer it is left untreated.

Chris wrote at 2006-12-07 20:38:13
I would agree with Hilary's statement of the expertise of Veterinarians but the truth is, a 6 or 9 volt battery in a collar is not enough voltage to cause burns in skin tissue.  Leaving a containment collar (or any collar) on your pet that is too tight and for too long will cause the tissue under the collar to deteriorate (known as pressure necrosis).  You need to make sure the collar is adjusted properly, leave the collar on for only 8 hours at a time, check your pet's neck daily for redness or sores, and clean your pet's neck and the collar on a regular basis.

Kristen Cabe - AllExperts Expert wrote at 2007-07-11 14:48:21
Actually, Hilary, your answer is incorrect. I realize this is an old question and answer, but I wanted to reply since your response was not only biased against electric collars, but gave incorrect information.

Pressure necrosis is caused by the pressure of the two probes on an electric collar, in the same place on a dog's neck, when worn for extended periods of time. It is NOT a result of the collar burning the dog. These collars emit a static shock, similar to what you feel when you get out of your car and are shocked when you touch the door to shut it. It's enough to get your attention, but it does not cause pain, or damage, or burns.

If your dog is going to be wearing an electric collar for longer than a few hours at a time, you should periodically move it to a different spot on his neck to prevent pressure necrosis.

sandra wrote at 2008-03-09 22:44:18

I am sorry you are so mis-informed and leading others with your false information.  This IS Pressure Necrosis, NOT burns, there is no heat generated in these collar.  How often have you burned yourself when you drag your feet on the carpet and touch something.  That is a static correction, like the kind we are talking about.  People - please do your research and ask a qualified veterinarian that has dealt with these collars!


al wrote at 2008-03-09 22:52:04
IF these were really electrical "burns", then my dog would never have gotten them with his collar set on "tone-only"  - no electrical stimulation.  I left the colllar on for a couple weeks and he had been playing with other dogs in the sand.  The sand/dirt and constant pressure caused the necrosis and  it healed up in a few days.  Now he wears it at when out on patrol and has neck is cleaned weekly as suggested.  PLEASE DON'T SPREAD FALSE INFORMATION!  don't we have enough ugly fences - the invisible fences work!

doglife wrote at 2008-03-10 01:36:25
Hilary, you ignorant person.  Get your facts straight!  You should not continue to misinform pet owners.  These containment systems are the right choice and totally safe for the vast majority of pets and owners!

Peter H. Eeg DVM wrote at 2008-05-01 17:44:38
Dear Sirs,

In actuality the company is correct in this case.  I have researched this common misconception and discovered that the milliampere that are produced by electronic pet containment receivers are far too low to cause cellular fluid heating, cell membrane destabilization, cellular damage or cell death.  

The inflammatory condition that has been noted is due in fact to contact trauma to the dermis resulting in reduced blood flow to the tissue and initiation of secondary bacterial dermatitis further inflaming the dermis.  If allowed to progress unchecked ulceration, denaturization and tissue necrosis will be the eventual n-stage result.  All collars; nylon, leather, chain or other should be routinely checked for any signs of damage to the hair and skin.

Peter H. Eeg DVM

David wrote at 2008-07-14 19:28:06
I hope you are studying veterinary medicine somewhere reputable.  I would also do some research on pet containment fences before I answered questions incorrectly.  The static shock correction that comes from a computer collar is only a 3 to 6 volts.  The electrical stimulation that comes from the common "Ab stimulators" you see on T.V. or the TENSunits used for human muscle physical therapy are much stronger than this and they activate for much longer periods of time. It is virtually impossible for any pet fence collar to cause a burn.  The correct answer is, pressure necrosis.  This is similar to a bed sore and is caused by constant pressure on tissue over time, causing damage and death to the surrounding cells.  This is also similar to a collar being embedded in a dogs neck from being too tight for too long.  For more information on embedded collars and pressure necrosis, contact your local veterinarian.

Todd Music wrote at 2008-08-08 23:23:27
These are not burns. They are produced by leaving the collar on for extended periods of time. The syndrome is called pressure necrosis, similar to a bed sore. The electronics can not elevate temperature.

Pete wrote at 2008-09-12 02:34:48
Although your vet may be correct that they are in fact burns.  Pressure necrosis typically results from leaving the collar on for an extended period of time OR improperly fitting the shock collar around the dogs neck (too tight). Essentially, causing the blood supply of that area to be restricted. Pressure necrosis can cause infection, hairloss or alopecia, tenderness, erythema, swelling, exudation, and crusting. If it is in fact pressure necrosis repeated cleanings would be advisable.

Opie wrote at 2008-10-30 17:06:52
The previous answer is absolutely incorrect, and, if written by a vet, it was from a vet that did not study long and hard for their license. NO, your dog is not burned. There is NO electricity in those collars. They run on batteries. Therefore, they emit a STATIC rather than electric correction. It is scientifically impossible for a 3 or 6 or 9 volt battery to "burn" anything. This is simple and common knowledge.  

Minnesota Vet. wrote at 2010-03-05 21:14:24
E-collars do not generate enough electrical charge to burn tissue.

E-collars operate on approx. 7 volts and mili-amperage, it is called static electricity.   Pressure Necrosis is many times confused (even by Veterinarians) as a burn from an e-collar.  Hilary Schiavone the so called expert, is absolutely WRONG on her advise regarding this topic.  

Dog trainer wrote at 2010-05-08 01:35:24
The response by "Hilary" the expert is TOTALLY incorrect.  

Your dog has pressure necrosis from wearing the e-collar to long or it is on to tight.  I'd recommend finding a new vet.  e-collars operate on a very low amperage, they do not have enough electrical charge to burn skin!  

Reason Trumps Feelings. wrote at 2011-01-08 18:47:53

The problem is called Pressure Necrosis. Not burn necrosis. Any object which is in constant contact with the same area of skin (not the fur) under pressure (from the collar)of a dog can cause this. Do not leave the collar on constantly and keep the area clean and this will not happen. The collar is a training tool and should not be worn 24-7. In my experience some vets are vehemently opposed to this form of correction and tell their patient's owners that the collar causes burns. I have put the collar on my bare leg and activated it. The sensation was shocking, pardon the pun, but it did not burn me.

Tom wrote at 2012-01-20 23:42:55
I just wanted to post my own experience with my dog and this condition.  My dog rarely tests the boundaries of the fence after the initial training and as a result rarely gets a correction any longer however, he still occasionally gets this condition if we do not tend to his collar periodically.  What we were told to do works well and that is to attach a weight to his collar about 1/2 of the way around the collar from the receiver so that it would cause the receiver to ride on one side of his neck or the other.  Flip the collar over about once every couple of weeks.  Since we have been doing this, there have been no more issues.

Jeff wrote at 2013-04-07 11:16:48
New answer to an old question.  

Of course, it is pressure necrosis.  I recently accepted an offer from a friend to take care of my dog for  10 days.  I forgot to remind her to remove the ecolllar nightly or when not in use. After 7 days she noticed a smell and discovered a necrosis. The collar was TURNED OFF the entire time.

Merely using a heavy duty plastic strap worn too tightly for too long to the skin will trap irritants, moisture, dirt and cause rubbing that can kill the skin; no electricity needed. The two probes constantly rubbing especially if your dog sleeps on the unit speeds the process.  Following other's advice of limiting time, cleaning and checking the area, and moving the unit around will prevent any problems.


Lady. DVM wrote at 2014-05-28 21:59:52
I have a dummy no-bark e-collar, that I put on my dog periodically.  It has plastic contact points and no electronics or battery in it.  Guess what... my dog develops sores with this fake unit every so often.  Why??  It is from the pressure of the plastic contacts pushing on the blood vessels in the tissue underneath, and stopping the blood flow.  Tissue without any blood supply can die rapidly and you have sores that "look like burns" develop.  Hope this info. helps.  

Vance Plummer wrote at 2015-05-19 09:25:49
Electronic collars utilise electronic stimulation (ES) not electric shock. ES is the artificial stimulation of a living tissue by means of an electric field or current (IEC). The ES delivered by modern electronic collars is transcutaneous electrical nerve stimulation (TENS), which artificially stimulates nerves and sensory receptors. TENS has no injurious consequences and is often used to manage chronic pain in humans. Typically the ES travels through tissue between two electrical contact points, which are applied to the skin. The ES is contained to the skin and superficial tissues when the contact points are less than 60mm apart The ECMA (Electronic Collar Manufacturers Association) Technical Requirement states that these skin contacts must be less than 60mm apart confining the ES to the skin and superficial tissues of the ventral neck.

The ES works by activation of local skin receptors called nociceptors. These normally detect pain and convert pressure, chemical signals or thermal ranges into electrical signals that are transported to the brain for interpretation. There are different types of nociceptors for different types of stimuli. Low-level ES confuses low threshold type Aδ nociceptors and medium level ES confuses high threshold type Aβ nociceptors into a response, that is, sending a signal to the brain. The ES is perceived as a prickling sensation cannot justifiably be described as pain (IASP, 2010). Like low and medium level ES, high-level ES causes no physical damage but the signals sent to the brain are perceived as pain so a high level ES can therefore justifiably be described as a painful and emotionally distressing event. The pain sensation following high-level ES is described as physiological pain because it is not associated with any tissue damage. The physiological pain of high-level ES occurs because of the inclusion of type C nociceptor stimulation. Pathological pain which follows tissue damage as a result of accidents or surgery is intense and can be very persistent unlike physiological pain. (Electronic RT in Perspective - David Chamberlain BVetMed., MRCVS.).

The difference?...Electric shock is the sudden application of electric current to a living organism with sufficient strength and duration to produce a convulsive or thermal effect (IEC) with injurious exposure consequences (Reilly 1998). Typically electronic shocks occur when mains electricity accidentally travels through an animal’s or human’s body to earth.

Recently the Companion Animal Welfare Council published a literature review of electronic collar studies (CAWC 2012) in which it avoided the use of the term ‘shock’ because it was associated with biased personal opinion and emotional connotations. In a very recent independent study into the characteristics of electronic collars the term shock, electric shock or electrocution were not used by the authors when describing the characteristics of electronic collars (Lines et al., 2013). The term ‘shock’ also implies a certain magnitude of discharged electrical energy, which is not a characteristic of modern electronic collars (Lindsay 2005).

Electronic collars have been commercially available since the 1970’s and these original devices were relatively primitive. These historic collars did deliver quite substantial currents hence the coining of the term ‘shock’. However this is not a term, which is appropriate to associate with modern electronic collars as the devices have evolved along with understanding of how animal’s learn to be much milder and more effective systems (CAWC 2012).

On many websites concerning animal welfare, there are multiple uses of the words “shock collars” when describing electronic training collars. These websites often use such words to enhance their position on why not to use electronic dog fences. Often the written material deals in absolutes and frame the use of an electronic collar such that it “will” cause harmful effects such as “burning skin” and “convulsions”, “detrimental behavioural distress” and that the electronic training collars are “ineffective” overall. The RSPCA website details clearly its philosophy and opinion on electronic collars by opposing the use of the devices with a strong concern of misuse more so than the devices themselves. The word “shock” is still used, but far more conservatively than in recent years, likely largely due to a court case that ruled against the RSPCA due to inaccurate and misleading information regarding electronic collars.

Presumably, if electronic pet containment products are inflicting the harmful effects various groups would like to propagandise (Orion v RSPCA Vic), there would be epidemic proportions of pets ending up in veterinary clinics and quantified cases of lawsuits as direct results of the use of such devices. It could be argued that more pets end up in veterinary clinics as the results of poor physical fencing issues or being tethered inappropriately.

This type of propaganda is both inaccurate and opinion only. Research investigating the effectiveness of electronic dog fences and electronic training collars has shown repeatedly that the devices do not cause injury and when used with understanding of operant training principles, are very effective teaching tools.  While hidden fences are effective tools, the welfare benefits of them need to be considered as some organisations object to them on welfare grounds. These objections are philosophical only.

Vance Plummer

Managing Director

Hidden Fence


Angela Critchley. ECMA (electronic collars manufacturers association)

Companion Animal Welfare Council (CAWC) (2012), The Use of Electric Pulse Training Aids (EPTAs) in Companion Animals.

International Electrotechnical Commission (IEC) is the world’s leading organisation that prepares and publishes International Standards for all electrical, electronic and related technologies.

Lindsay, S.R. 2005. Handbook of Applied Dog Behavior and Training. Vol 3, Procedures and Protocols. Blackwell Publishing, Ames Iowa. pages “Shock Collars are Bad for barking dogs” Dr Katrina Ward, Tuesday, 25   February 2014

“Comparison of stress and learning effects of 3 different training methods” (Hanover University 2008)  E.Schalke, Y. Salgirli, I. Bohm, S. Ott, H. Hackbarth Institute of Animal Welfare and Behaviour, University of Veterinary Medicine Hanover


Orion Pet Products Pty Ltd v Royal Society for the Prevention of Cruelty to Animals (Vic) [2002] FCA 860

International Electrotechnical Commission (IEC) is the world’s leading organisation that prepares and     publishes International Standards for all electrical, electronic and related technologies.

      Lines J. A., van Driel K., Cooper J. J. (2013) The characteristics of electronic training collars for dogs, The Veterinary Record, January 13, 2013.

      Reilly, J, P. Applied Bioelectricity: from electrical stimulation to electropathology, New York: Springer, 1998.

© 2002-2015 Canine Containment Company Pty Ltd. All rights reserved. DogWatch Hidden Fence Systems, The Hidden Fence Company and The Hidden Fence Company logos are all Registered trademarks of the Canine Containment Company Pty Ltd. Vance Plummer

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Hilary Schiavone-Brensinger


I am very knowledgable in small animal health, care, and behavior. I have five cats, three ferrets, two birds, and a dog of my own, so I have a very broad spectrum in different domesticated species. I am also very knowledgable in disease, sickness, and ailments that are common among our pets, and also treatments. I am an extreme animal lover and am also a part of an animal rescue organization.


I have been a veterinary technician for the past four years at both private and emergency practices. I belong to an animal rescue organization, and also am owned by alot of animals in my home! I can also answer any questions relating to orphaned wild baby birds. I am currently studying Veterinary Medicine.

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