Effects of restrictive and non-restrictive harnesses on shoulder extension in dogs at walk and trot

Influence of Wearing a Tactical Harness on Three-Dimensional Thoracic Limb Kinematics

OBJECTIVE

 The aim of this study was to assess the impact of a tactical harness on three-dimensional motion of the thoracic limb in dogs.

ANIMALS

 Five adult mixed-breed dogs (age: 4-6 years, weight: 25-35 kg) were used in this study.

METHODS

 Custom-fit tactical harnesses were applied to each dog and 19 retroreflective skin markers were used to determine three-dimensional joint motion during dynamic motion, with and without the harness. Sagittal plane (flexion-extension), transverse plane (internal-external rotation), and frontal plane (abduction-adduction) kinematics were created for the shoulder, elbow, and carpus from motion capture data, with and without the harness. Kinematic waveforms were analysed using statistical parametric mapping paired t-tests (a = 0.05). Angular displacements were determined, and total joint range of motion was compared using paired t-tests (a = 0.05).

RESULTS

 Wearing a tactical harness increased sagittal angular displacement in the elbow but decreased it in the shoulder and carpus. Significant differences were found in the kinematic waveforms in almost all joints at both a walk and trot. Dogs wearing the tactical harness had reduced flexion and increased abduction of the shoulder joint at a walk. The elbow joint had increased extension, reduced external rotation and increased abduction at both walk and trot. The carpus had reduced flexion at a trot and walk, as well as increased internal rotation and abduction at a walk.

CONCLUSION

 Wearing a tactical harness affected kinematic gait data of all joints of the forelimb. The elbow was affected in all three planes at both a walk and trot, while the shoulder joint was only affected at a walk when wearing a tactical harness.

CLINICAL RELEVANCE

 The clinical impact of wearing a tactical harness is unknown at this time, particularly when dogs are performing their duties while wearing harnesses.

Effect of harness design on the biomechanics of domestic dogs (Canis lupus familiaris)

Harnesses have become increasingly popular and whilst there are benefits to harnesses, the impact of harness design on canine biomechanics, and thus physical health and welfare is largely unknown. The purpose of this study was to assess the effect of three popular commercially available harnesses on canine locomotion in 66 domestic dogs. Dogs were filmed moving on a loose lead over a Tekscan Strideway gait analysis system. Stride length as a proportion of limb length (calculated as distance from the elbow to the floor), body weight distribution in the front versus the hind limbs (%), and minimum and maximum apparent angles of the lateral epicondyle of humerus (LEH) and greater tubercle of humerus (GTH) during the motion cycle were measured. Except for GTH angles, there were significant differences in all the investigated metrics. Differences varied across breeds/breed types. It is recommended that, when purchasing and fitting harnesses for dogs, owners and harness fitters treat dogs on an individual basis. The impact of pulling in harness on dog gait requires investigation as dogs may experience greater restrictions when pulling than during locomotion on a loose lead.

Interactive, Browser-Based Graphics to Visualize Complex Data in Education of Biomedical Sciences for Veterinary Students

In veterinary education, data from biomedical or natural sciences are mostly presented in the form of static or animated graphics with no or little amount of interactivity. These kinds of presentations are, however, often not sufficient to depict the complexity of the data or the presented topic. Interactive graphics, which allow to dynamically change data and related graphics, have rarely been considered as teaching tool in higher education of biomedical disciplines for veterinary education so far. In order to study the applicability and the usefulness of interactive graphics in biomedical disciplines for lecturers and students in veterinary education, three different courses from biomedical disciplines were exemplarily implemented as interactive graphics and evaluated in a pilot study by a survey amongst lecturers and students of our university. The interactive graphics were built using the Shiny environment, a web-based application framework for the statistic software R. The survey amongst lecturers and students was based on questionnaires covering questions on the handling and usefulness of the digital teaching tools. In total, n = 327 students and n = 5 lecturers participated in the evaluation study which revealed that the interactive graphics are easy to handle for lecturers and students, and that they can increase the motivation for either teaching or learning. In total, 71% of the students affirmed that interactive graphics led to an increased interest for the presented contents and 76% expressed the wish to get taught more topics with interactive graphics. We also provide a workflow that can be used as a guideline to develop interactive graphics.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40670-022-01613-x.

Use of acoustic myography to evaluate forelimb muscle function in retriever dogs carrying different mouth weights

OBJECTIVES

To evaluate the effect of mouth weight on gait and relative function of forelimb muscles in retriever hunting dogs as a possible explanation for biceps tendinopathy.

METHODS

Ten sound retriever dogs underwent acoustic myography, measuring efficiency (E-score), spatial summation (S-score), and temporal summation (T-score) during walk and trot on a pressure-sensitive walkway while carrying a 0 lb (0 kg), 1 lb (0.45 kg), and 3.2 lb (1.45 kg) mouth weight. Gait data included total pressure index (TPI), step length, and stance time. Statistics included a mixed effects model significant at p < 0.05.

RESULTS

Forelimb TPI increased with increasing weight. There was no significant change in individual muscle parameters in response to weight. Significance was found in between-muscle comparisons. For walk, T-score was significantly lower in triceps vs. brachiocephalicus with 1 lb, not with 3.2 lb., S-score was significantly lower in the biceps at 0, 1 lb, and triceps at 0 lb. when compared to brachiocephalicus, E-score was significantly lower in deltoideus vs. brachiocephalicus at trot with l and 3.2 lb. There was an overall significant effect of muscle on T-score at trot, but no individual muscle comparison was significant.

CONCLUSION

Forelimb load increases with mouth weight. Deltoideus had a longer contraction time in response to increasing weight at trot when compared to brachiocephalicus. The biceps muscle did not show increased work in response to increasing weight.

CLINICAL RELEVANCE

The underlying etiology of biceps tendinopathies in retriever dogs remains uncertain but is not due to increasing weight.

Influence of Two Types of Guide Harnesses on Ground Reaction Forces and Step Length of Guide Dogs for the Blind

Simple Summary

Guide dogs for the blind are an important tool for their handlers to live an independent life. As previous studies have shown, the harness has a significant impact on the dog’s kinematics and exerts pressure on special areas of the dog’s body. The aim of the study was to evaluate the influence of two types of harness on the force distribution between the paws. To measure the influence of the harnesses, we compared the vertical ground reaction forces in the working harness of a guide dog (Norwegian type) and in a Y-harness, each with a leash, a straight handle and a handle bent on the left side. Furthermore, the ground reaction forces were measured in dogs with collar and leash. Twelve certified guide dogs were included in the study. Compared to walking with collar and leash, none of the harnesses, when used with a leash, had an effect on the evaluated parameters. When the dogs walked in the harness with a handle and, as is common when leading blind people, under a light pull, there were clear effects on the impulse. Future studies should be devoted to the type of attachment of the harness, as well as the angle of attachment, which is altered by the size of the handler.

Abstract

Few studies exist addressing the effects of guide dog harnesses on dogs biomechanics. The aim of this study was to investigate how two different harness types affect ground reaction forces and stride length. Twelve certified guide dogs were tested under different conditions: walking with a collar and leash, walking with the harness used daily (Norwegian type with straight handle) and walking with a Y-harness using a straight or a curved handle. The parameters studied included maximum vertical force, vertical impulse and stride length. Compared to walking with a collar and leash, none of the harnesses, when used with a leash, had an effect on the evaluated parameters. However, both harnesses, when used with a handle and under re-enactment of the lead work, showed clear effects on the impulse. Stride length was shortened if the Y-harness with handles was used. Future studies should focus on the type of attachment of the harness, as well as the angle of attachment, which is altered by the size of the handler. The development of individually adapted harnesses in order to subject these animals to as little stress as possible during their daily work should be one of the future areas of research.

Lead pulling as a welfare concern in pet dogs: What can veterinary professionals learn from current research?

Veterinary professionals (VPs) are often the first source of advice for clients struggling with their dog's behaviour, and pulling on the lead is a commonplace undesirable behaviour VPs will encounter regularly in practice. Excluding bites, being pulled over while walking on a lead is the leading cause of non-fatal dog-related injuries in the UK. This narrative review investigates lead pulling as a welfare concern in pet dogs, highlighting aspects of the literature of particular interest to VPs. Lead pulling could negatively affect walk quality, frequency and duration, causing weight gain, while decreased environmental enrichment could trigger other undesirable behaviours. Aversive equipment to prevent lead pulling can cause pain, distress and injury, but even equipment considered humane can have welfare consequences. Punitive training methods could cause dogs stress, fear and anxiety and trigger aggressive behaviour. While these lead pulling outcomes are welfare concerns in themselves, they could also weaken dog-owner attachment, a risk factor in pet dog relinquishment. Given lead pulling could affect the welfare of patients in a VPs care, clinical implications and opportunities for client education are outlined. Educating clients on humane prevention and modification of lead pulling could make walks easier, safer and more enjoyable, with positive outcomes for clients, canine welfare and the practice.

Development of a detailed canine gait analysis method for evaluating harnesses: A pilot study

Dog harnesses are becoming more popular, with their large variety stemming from the idea that different dogs and scenarios require different types of harnesses. While their benefits over collars are self-explanatory, there is a lack of research on their effect on gait, and even the existing studies examine only a limited set of parameters. The goal of present study was to establish a method capable of quantifying canine gait in detail. Based on 3D motion capture, the developed method allows for the examination of 18 joint angles and 35 spatio-temporal parameters throughout multiple gait cycles, and can be used to analyze canine movement in detail in any kind of scenario (e.g. comparing healthy and lame dogs, or measuring the effect of training). The method is presented through the measurement of how different harnesses affect walking kinematics compared to free (unleashed) movements. Four dogs with varying body sizes and breeds and multiple types of harnesses were included. Marker data was filtered using a zero-lag 6th order Butterworth-filter with a cutoff frequency of 20 Hz. The normality of the spatio-temporal and joint range of motion parameters was tested using the Anderson-Darling test (p = 0.05), with most parameters passing in 60+% of test cases. Swing time and range of motion of the sagittal aspect of spinal angle at T1 vertebrae failed more regularly, both resulting from the measurement setup rather than the actual parameters being not normally distributed. Two-sample Kolmogorov-Smirnov tests (p = 0.05) were used to compare each parameter’s distribution between cases, showing that most parameters are significantly altered by the harnesses in about 2/3rd of the cases. Based on the results, there’s no absolute superior harness, however, it is possible to select the best fit for a specific dog and application, justifying their large variety.

Dog Pulling on the Leash: Effects of Restraint by a Neck Collar vs. a Chest Harness

Leash pulling is a concern for dog owners and can be detrimental to the health and welfare of dogs. Neck-collars and back-connection harnesses are popular restraint types. Harnesses have been proposed as a better and more considerate option for canine health and welfare. Anecdotally, dogs pull more when wearing a back-connection harness; however, there is no scientific evidence for this perception. This study aimed to investigate how strongly dogs pull on the lead to achieve a food treat or toy under restraint by a neck-collar versus a back-connection harness. A within-subject counterbalanced design was used for the study, involving 52 shelter dogs. A customised canine leash tension metre was connected to the collar or harness to record the pulling of the dogs, including measuring the maximal and mean leash tension, and the time spent pulling. In addition, dog behaviours were recorded using two cameras from two separate directions. The maximal and mean leash tension and the pulling time were greater under restraint by harness when attracting dogs with food treats. No significant difference between harness and collar was found in potential stress-related behaviours (e.g. tail and ear positions, lip-licking, and panting). However, dogs looked at the experimenter more often when restrained by harness than collar in the food treat attraction test. No significant difference was detected between harness and collar with respect to leash tension and stress-related behaviours in the toy attraction test. These findings suggest that dogs tend to pull stronger and more steadily when wearing a back-connection harness compared to a neck collar to reach the food treat but not the toy.

Preventive Health Care for Working Dogs

The goal of preventive care is to maintain and optimize health by averting preventable problems. Effective preventive care programs for working dogs must incorporate standard procedures applicable to dogs in general with additional elements pertinent to the more specific characteristics of breed, geographic location, living and working conditions, and physical and mental tasks required of the working dog. This article covers the basic essential preventive health guidelines for all working dogs as well as the specific breed, occupational, and regional considerations to be taken into account.

A comparison of apparent neck and back angles before, during and after canine hydrotherapy

Research examining canine hydrotherapy is distinctly lacking despite the increasing use of hydrotherapy as a rehabilitation tool and as part of a fitness programme. Due to this paucity of research, the aim of this study was to examine differences in apparent neck and back angles of dogs both before, during and after hydrotherapy sessions. Anecdotally, these are the anatomical locations where concern of injury risk lies. Thirty-one dogs were filmed trotting both prior to and post participation in hydrotherapy as well as during the hydrotherapy session. Data were then analysed using Dartfish software. There was no significant difference in the neck angle of the dogs between swimming and trotting (P=0.859) however, dogs had a significantly greater back angle when swimming compared to trotting (P=0.05). The use of buoyancy aids during hydrotherapy, showed no significant difference in neck or back angles compared with no buoyancy aids. This study begins to provide evidence on the effect of hydrotherapy on canine kinematics. It can be used to inform rehabilitation and fitness regimes for dogs with the aim to improve the long-term health and welfare of dogs.

Alterations in the ground reaction force of dogs during trot after immobilization of the stifle joint: An experimental study

This study aimed to evaluate changes in the vertical and fore-aft force generation of the hindlimbs in dogs with stifle orthoses. Custom-made orthoses were used on the right stifle joint. Force plate and marker data from four beagle dogs in trials without orthoses, with fixed orthoses, and with unfixed orthoses were collected. The vertical ground reaction force of the right side was increased with fixed orthoses and decreased with unfixed orthoses compared to that of gait without orthoses. When compared to that of gait without orthoses, the fore-aft ground reaction force changed with fixed orthoses but not with unfixed orthoses. It is suggested that the level of constraint of the orthosis affected the ground reaction force pattern.