27/08/2026
My good friend and colleague has written a much needed piece regarding Grot and Prong Collars on Dogs.
Author: Rebeccah Baylis: Animal Physiotherapist, Little Green Stables
An evidence-aware overview for dog parents, trainers and animal professionals.
Grot and prong collars concentrate force around a small and anatomically sensitive area. Their potential effects depend on fit, positioning, lead tension the force applied and the individual dog's health.
Introduction:
Grot and prong collars are designed to sit high around a dog's neck and apply pressure when the lead tightens. A grot collar is typically a very narrow slip-style collar, while a prong collar uses inward-facing metal links that tighten against the skin.
Although they work in different ways, both concentrate force over a relatively small and sensitive area.
The concern is not simply that a collar touches the neck. A comfortably fitted flat collar used for identification is very different from equipment that tightens, pinches or delivers repeated corrections. The possible effects vary according to the collar's width and position, the speed and amount of force applied, how often the dog pulls or lunges, and the dog's individual anatomy, behaviour and health.
Why the Neck Is Particularly Vulnerable:
A dog's upper neck contains far more than skin and muscle. Beneath and around the collar lie structures involved in breathing, swallowing, circulation, sensation and movement. These include the larynx, trachea, oesophagus, hyoid apparatus, thyroid gland, salivary tissues, lymph nodes, major blood vessels, cervical nerves, vertebrae, muscles and fascia.
The hyoid apparatus is a delicate chain of small bones supporting the jaw, tongue and larynx. It provides attachment for muscles involved in tongue movement, swallowing and positioning of the upper airway. During swallowing, the hyoid and laryngeal structures must move in a coordinated way. Pressure beneath the jaw or around the upper throat may therefore impact upon the muscles, fascia and other soft tissues surrounding this system. The hyoid itself is extremely delicate and can easily be fractured.
Pressure, Pain and Tissue Injury:
Pressure depends on both the force applied and the size of the contact area. A thin cord or individual metal prongs spread force across a much smaller surface than a broad, padded material. This produces greater pressure at each point of contact. Studies using live dogs and simulated neck models show that collar design and lead force affect the pressures applied to the neck (Hunter, Blake and Ferro de Godoy, 2019; Carter, McNally and Roshier, 2020).
• Pinching, bruising, inflammation or local tenderness.
• Broken hair, abrasions, ulcers or puncture wounds.
• Increased touch sensitivity around the head, jaw, throat and neck.
• Protective tension through the neck, shoulders and upper back.
• Coughing, gagging, retching or repeated swallowing when pressure is applied.
• Reluctance to lower, turn or extend the head and neck.
• Defensive or avoidant responses when the collar or lead is approached.
Note: if protective tension through the neck, shoulders and upper back persist, you are likely to have posture change and compensation patterns arise through the body.
Breathing and the Upper Airway:
The larynx sits at the entrance to the trachea and is essential for breathing, vocalisation and protecting the airway during swallowing. When a collar tightens over this region, a dog may cough, gag, swallow repeatedly or show noisy breathing. Strong or sudden pressure may temporarily compress soft tissues around the throat and make breathing less comfortable, particularly when the dog is exercising, panting or highly aroused.
Dogs with brachycephalic obstructive airway problems, tracheal weakness, laryngeal disease, previous neck trauma or existing respiratory compromise may be especially vulnerable. It would be inaccurate to state that every collar correction collapses the trachea or permanently damages the airway. However, coughing, vocal changes, breathing difficulty or exercise intolerance should never be dismissed as a normal training response.
Recent research found that restraint type can influence respiratory rate and intraocular pressure, with brachycephalic dogs requiring particular consideration (Bailey, Packer and Wills, 2025).
The Hyoid Apparatus and Swallowing:
The hyoid apparatus supports the tongue base and connects functionally with muscles of the jaw, throat, sternum and larynx. It contributes to swallowing and helps position the larynx. A collar placed immediately behind the jaw may lie close to tissues associated with the hyoid and pharyngeal region.
Repeated pressure can contribute to discomfort when swallowing, jaw or tongue tension, head-shyness, sensitivity around the throat or reluctance to take food while wearing the collar. The hyoid is a delicate structure and can easily be fractured.
Nerves and Protective Responses:
The neck contains a complex network of sensory and motor nerves. Branches of the vagus nerve and recurrent laryngeal nerves contribute to laryngeal function, while cervical spinal nerves supply the neck, shoulders and forelimbs. Painful or unpredictable pressure activates sensory pathways and may provoke an immediate protective response. The dog may stiffen, lower or retract the head, brace through the shoulders, freeze, spin, vocalise, redirect or attempt to escape. Severe trauma can injure nerves. Repeated painful stimulation may increase guarding, sensitivity and anxiety around handling and lead to posture change and compensation through the body, increasing injury risk.
Circulation and Pressure within the Eyes:
One of the better-supported physiological concerns associated with neck pressure is an increase in intraocular pressure. Research has found that pulling against a neck collar can raise pressure within the eyes, whereas force applied through a harness does not necessarily produce the same response. Controlled studies found that pressure through a neck collar increased intraocular pressure, whereas a harness did not produce the same increase under the tested conditions (Pauli et al., 2006; Bailey, Packer and Wills, 2025).
This may be particularly relevant for dogs with glaucoma, previous eye surgery or other ocular conditions in which an increase in eye pressure may be undesirable. Also think about the potential strain for our “Bug eyed or Brachi breeds”.
Muscle Tension, Posture and Movement:
A dog anticipating pressure may alter its posture before the lead tightens. It may shorten the neck, lower the head, brace the jaw or shift its body away from the expected pressure. These adaptations may affect the sternocephalicus, brachiocephalicus, trapezius and muscles supporting the shoulder girdle and thoracic sling. However, fascia is a connective web so whatever pressure is placed will affect the whole body.
• Tension around the jaw, neck, shoulders and upper thorax.
• Reduced willingness to rotate, extend or lower the neck.
• Shortened or asymmetrical movement.
• Altered weight distribution and compensatory loading.
• Discomfort during grooming, handling or equipment fitting.
Pain, Fear and Behavioural Suppression:
Physical discomfort and behaviour cannot be separated. If pain occurs while the dog is looking at another dog, a cyclist, a child or a particular environment, the dog may associate that trigger with the discomfort. This may increase fear, anxiety, vigilance, frustration or defensive behaviour.
A collar may suppress pulling or lunging temporarily, but this does not necessarily change the underlying emotion or teach an alternative behaviour. A dog that becomes very still or quiet following a correction should not automatically be described as calm. Stillness may represent freezing, avoidance or behavioural suppression.
Dogs Who May Be Especially Vulnerable:
No dog should wear a Grot or Prong, however the below dogs may be especially vulnerable:
• Puppies, adolescent and senior dogs.
• Small, fine-necked or brachycephalic breeds.
• Dogs with coughing, airway, laryngeal or tracheal problems.
• Dogs with neck, spinal, neurological or ocular conditions.
• Dogs with previous injury or surgery around the head, throat, shoulders and forelimbs
• Anxious, reactive, highly aroused or touch-sensitive dogs.
• Dogs that pull, lunge or hit the end of the lead at speed.
A More Appropriate Approach:
The aim of training should be to support the dog's understanding and emotional response, rather than simply stopping visible human undesired behaviour through discomfort.
A well-fitted, non-restrictive harness can distribute lead forces over a broader area of the body. It should allow normal shoulder movement, avoid pressing into the throat or armpits and be checked regularly as the dog grows or changes shape.
Equipment alone will not teach loose-lead walking. It should be combined with reward-based training, gradual exposure and appropriate distance from triggers and management that prevents the dog from repeatedly becoming overwhelmed.
Conclusion:
Grot and prong collars concentrate force around an anatomically complex area containing structures essential for breathing, swallowing, circulation, sensation and movement. Their use may cause pain, tissue irritation, coughing, gagging, muscle bracing, increased eye pressure, altered posture and negative emotional associations.
The known potential for pain, distress, local injury and behavioural fallout provides a strong welfare-based reason to avoid them. (Ridgway, 2026).
Good training should improve safety, communication and confidence. It should not depend on applying pain or concentrated pressure to a dog's throat.
References:
Bailey, M.E., Packer, M.J. and Wills, A.P. (2025) 'Effect of a collar and harness on intraocular pressure and respiration rate of brachycephalic and dolichocephalic dogs', Veterinary Medicine and Science, 11, e70384. doi: 10.1002/vms3.70384.
Carter, A., McNally, D. and Roshier, A. (2020) 'Canine collars: an investigation of collar type and the forces applied to a simulated neck model', Veterinary Record, 187. doi: 10.1136/vr.105681.
Hunter, A., Blake, S. and Ferro de Godoy, R. (2019) 'Pressure and force on the canine neck when exercised using a collar and leash', Veterinary and Animal Science, 8, 100082. doi: 10.1016/j.vas.2019.100082.
Johnson, A.C. and Wynne, C.D.L. (2024) 'Comparing efficacy in reducing pulling and welfare impacts of four types of leash walking equipment', PeerJ, 12, e18131. doi: 10.7717/peerj.18131.
Pauli, A.M., Bentley, E., Diehl, K.A. and Miller, P.E. (2006) 'Effects of the application of neck pressure by a collar or harness on intraocular pressure in dogs', Journal of the American Animal Hospital Association, 42(3), pp. 207-211. doi: 10.5326/0420207.
Ridgway, M. (2026) 'Health implications of dog-worn equipment: a review of known and alleged physical risks', Frontiers in Veterinary Science, 13, 1711781. doi: 10.3389/fvets.2026.1711781.
Educational note: This document provides general educational information and is not a substitute for veterinary diagnosis, treatment or individual behavioural advice. Dogs showing coughing, gagging, swallowing difficulty, voice change, breathing problems, neck pain, eye problems or sudden behavioural change should be assessed by a veterinary professional.
