The Science

Studies measuring pulling forces document increased behavioural stress signs, higher pulling force, and neck loading that a harness distributes away from the cervical spine entirely.

This is the claim most harness brands avoid. The biomechanics literature is consistent: all harnesses restrict shoulder extension to some measurable degree compared to unrestrained movement. Y-front designs show a reduction of approximately 4.73 degrees at walk. Front-clip harnesses show even greater restriction across shoulder extension, flexion, elbow extension, and elbow flexion. "Non-restrictive" is not a term the science supports.

Whether a harness uses a Y-front, straight chest strap, or Norwegian design, the determining factor for gait impact is where the front strap sits relative to the shoulder joint. A well-positioned chest strap can outperform a poorly-positioned Y-front. The diagonal-across-the-scapula position is consistently the worst outcome in published studies.

Studies controlling for fit quality find it to be the dominant factor in gait alteration. The same harness, badly fitted, produces significantly worse outcomes than the same harness correctly fitted. Standard S/M/L sizing does not account for real variation in body shape, particularly in mixed breeds.

The goal is not to claim zero restriction. It is to minimise restriction at the joints that matter, distribute load away from the neck, and solve the fit problem that generic sizing cannot. Three independently-sized pieces (back, chest, belly) mean the harness is built around the dog in front of you, not a breed average.

The probiotic research is only as useful as it is specific. Daily administration of Lactiplantibacillus plantarum LP815TM for four weeks significantly improved aggression-related behaviours (p=0.0047) and anxiety-related behaviours (p=0.0005), with objective activity monitoring confirming faster settling and more consistent sleep. A separate study of L. plantarum PS128 showed stabilisation of both aggression and separation anxiety after 14 days, alongside a decrease in plasma serotonin turnover, suggesting improved neurotransmitter availability. Bifidobacterium longum NCC3001 produced behavioural improvement in 90% of anxious dogs, with 83% showing lower cortisol and 75% showing lower heart rate.

For dogs with atopic dermatitis, pruritus, or allergic skin conditions, the gut-skin axis is an active research area with meaningful findings. A 10-week randomised controlled trial found that a probiotic and nutraceutical blend supported significantly faster resolution of pruritus compared to placebo by week two. A separate study combining L. cremoris and L. paracasei showed reduced serum IgE levels and increased short-chain fatty acid production. An indole-rich postbiotic reduced scratching frequency by 20% and human-perceived itching by 27%.

Multiple studies find that combining a probiotic with a prebiotic produces greater microbiome modulation than either component alone, including enrichment of Faecalibacterium prausnitzii and increased butyrate production, both associated with gut barrier integrity and reduced systemic inflammation.

Function-specific formulations, not a one-size supplement. Each SKU is designed around a specific outcome (anxiety, skin, ageing, recovery), with strain selection driven by the evidence base for that outcome. No vague promises. No proprietary blends that hide what is actually inside.

EU Delegated Regulation 2026/131 introduced stricter requirements for the non-commercial movement of companion animals across EU member states, with tighter traceability requirements built around microchips and passports. For anyone travelling with a dog in Europe, the documentation burden has increased. Sund Pass is built to meet it.

The failure mode of paper and PDF health records is well-known to anyone who has handed their dog to a vet, a groomer, or a friend. The record lives in a drawer, or an email thread, or the previous owner's phone. Sund Pass makes the record the dog's, not the owner's. Scannable, shareable, always current.

Sund Pass is also the data layer that makes personalised product recommendations possible. A dog's health history, breed mix, weight, age, and known conditions are the inputs that make the difference between a generic supplement and one that is actually right for this dog. That is the direction Sund is building toward.