Slip leads on dogs: understanding the physical and psychological risks

Slip leads are commonly used in shelters, grooming environments, veterinary settings, and sometimes in training. They are often described as simple, lightweight, or effective for “quick control”. However, the way slip leads function — tightening under tension — means their impact on a dog’s physical body and emotional wellbeing is detrimental compromises welfare. Slip leads or choker chains are essentially a "noose" around the neck.

When a slip lead is positioned high on the neck, close to the skull and upper cervical spine (often referred to as being placed “over the axis”), pressure is applied near some of the most sensitive and vulnerable anatomical structures in the dog’s body. Current veterinary, bio-mechanical, and behavioural research suggests that this carries avoidable physical and psychological risks, particularly when dogs pull, lunge, or experience sudden leash tension.

A real-world observation from within the training industry

Concerns about slip leads are not limited to academic research. Anecdotal observations from within the dog training industry also raise red flags.

In a publicly shared training video, an aversive dog trainer (not named here) stated words to the effect of:

“Some dogs, such as Rottweilers, I have found will vomit when you put this on.”

Vomiting is not a sign of calm learning or compliance. It is a physical or phycological stress response, often linked to panic, airway pressure, vagal nerve stimulation, or acute distress. The fact that this response has been observed — and spoken about casually — should prompt serious reflection about whether such tools are appropriate, humane or safe.

The physical impacts of slip leads used high on the neck

Airway and throat compression

A dog’s neck contains vital soft tissues, including the trachea (windpipe), larynx (voice box), oesophagus, blood vessels, and nerves. These structures are not protected by bone and are easily compressed.

When a slip lead tightens, pressure can be applied directly to the airway. This may result in coughing, gagging, swallowing discomfort, or altered breathing patterns. Research examining restraint and leash tension has shown that neck-mounted restraint systems can compromise airway structures when dogs pull against them, particularly in smaller dogs and brachycephalic breeds.

Concentrated pressure and soft tissue strain

Slip leads apply force through a narrow band that tightens as tension increases. Unlike harnesses, which distribute force across the chest and torso, slip leads can concentrate pressure in one area of the neck.

Repeated or sudden tightening may contribute to:

• muscle soreness and inflammation

• bruising or localised tissue trauma

• irritation of superficial nerves

• sensitivity to touch around the neck

Over time, even low-level but repeated pressure can lead to discomfort that may not be immediately obvious but can influence movement and behaviour.

Increased cervical loading and upper neck strain

Biomechanical studies measuring leash tension during walking have demonstrated that meaningful force is transmitted to the cervical region when dogs pull. Experimental testing of collar systems, including slip leads, has shown that tightening devices increase focal pressure as load increases.

When a slip lead is positioned high on the neck:

• the dog has less ability to distribute force through larger muscle groups

• sudden leash tension can twist or torque the head and upper cervical spine

• dogs may brace, freeze, spin, or thrash in response

The upper cervical region plays a critical role in balance, coordination, and nerve signalling. Repeated strain in this area raises legitimate welfare concerns.

Increased intra-ocular (eye) pressure

Veterinary ophthalmology research has consistently found that pressure applied via a neck collar significantly increases intra-ocular pressure (IOP), while well-fitted harnesses do not produce the same effect.

Elevated intra-ocular pressure is a recognised risk factor in the development and progression of eye disease, including glaucoma. This is particularly relevant for dogs who pull strongly, are walked at speed, or are predisposed to ocular conditions.

The psychological and behavioural impacts

Stress and fear conditioning

Dogs do not perceive tightening neck pressure as guidance. For many, it is experienced as restraint, choking, or loss of control. When this sensation occurs repeatedly — especially in stimulating or unpredictable environments — dogs may develop anticipatory stress.

Over time, dogs can associate discomfort with:

• the lead being picked up

• specific walking environments

• other dogs, people, or handling cues

This can increase anxiety, reactivity, or avoidance behaviours rather than resolving them.

Reduced trust and handling sensitivity

Dogs exposed to repeated neck pressure may become head-shy, reluctant to be leashed, or avoidant of handling outdoors. Some dogs shut down behaviourally, appearing calm but emotionally disengaged. Others escalate, pulling harder or reacting more intensely.

These responses can erode trust and make future training and cooperative care more difficult.

Behaviour suppression is not learning

Slip leads can suppress behaviour in the moment — a dog may stop pulling or lunging temporarily to avoid pain. However, research in canine behaviour and learning shows that aversive physical pressure suppresses behaviour without addressing the underlying emotional state.

When the pressure is removed:

• the behaviour often returns

• emotional responses such as fear or frustration may intensify

• dogs may redirect stress into other behaviours

Learning is most effective when dogs feel safe, supported, and able to make choices.

Safer, welfare-focused alternatives

For dogs who pull or struggle on lead, evidence-based alternatives include:

• well-fitted Y-front harnesses that distribute force away from the neck

• long lines for decompression walks where appropriate

When paired with reward based training which science supports, these options support both physical safety and emotional wellbeing.

Scientific evidence supporting this article

The concerns outlined above are supported by a body of veterinary, bio-mechanical, and behavioural research:

• Studies measuring leash tension have shown that dogs pulling against neck-worn restraint systems experience measurable pressure and force applied to cervical tissues, which increases with pulling and sudden leash tension.

• Experimental testing of collar systems, including a slip lead, has demonstrated that tightening devices concentrate pressure as load increases, producing higher focal pressure than non-tightening systems.

• Veterinary restraint research has identified that pressure applied to the neck can compromise airway structures, particularly when dogs pull or resist restraint.

• Multiple controlled studies have shown that neck collars significantly increase intra-ocular pressure, while harnesses do not produce the same effect.

• Research into canine stress and learning indicates that aversive physical pressure is associated with increased stress responses, reduced learning efficiency, and negative behavioural outcomes.

• Veterinary and animal welfare organisations caution against the routine use of tightening neck devices due to risks of soft tissue injury, airway compromise, elevated eye pressure, and psychological stress.

References

Bailey, A. M., et al. (2025). Effects of collar versus harness use on intra-ocular pressure and physiological parameters in dogs.

Blake, R., et al. (2019). Measurement of pressure and force applied to the canine neck during leash walking.

Carter, A. J., et al. (2020). Comparison of pressure distribution from canine collar types including a slip lead. Veterinary Record.

Hunter, L., et al. (2019). Bio-mechanical assessment of leash tension and neck loading in dogs.

Ogburn, P. N., et al. (1998). Evaluation of restraint methods and airway effects in dogs.

Pauli, A. M., Bentley, E., Diehl, K. A., & Miller, P. E. (2006). Effects of the application of a neck collar and harness on intra-ocular pressure in dogs. Journal of the American Animal Hospital Association.

Schalke, E., et al. (2007). Stress symptoms caused by training methods in dogs.

Ziv, G. (2017). The effects of using aversive training methods in dogs: A review. Journal of Veterinary Behaviour.

Australian Veterinary Association. Policy and position statements on dog training equipment and animal welfare.