A biomechanical study on the hoof impact at the trot

This thesis is a study of the hoof deceleration and the propagation of impact related shock waves through the structures of the distal limb in the beginning of the stance phase. The equine limb has an in-built shock absorbing capacity, with an anatomy that gives a successive disto-proximal loading that prolongs the time of loading uptake. The repetitive impulsive loading subjected to the limb following each hoof impact has been suggested to be an important factor in the mechanical stress that if sufficiently repeated may lead to subchondral bone damage. The horses used in the study were Standardbred trotters. The deceleration pattern of fore- and hind hooves were recorded with accelerometers at different circumstances. In the first study, horses trotted at slow speed over a force plate. One accelerometer glued to the hoof wall, and one fixed to the third metacarpal bone, in order to record the transmission of impact transients. The initial impact peak was assumed to be negligible proximal to the fetlock joint. The length of the hoof braking seemed to influence on the attenuation of the following peak decelerations. In the following studies only hoof mounted accelerometers were used. In the second study the deceleration patterns of the fore- and hind hooves were compared over the force plate on a sand surface at slow trot. In the third study the hoof deceleration was compared between two different surfaces. The forth study was a field study on the hoof decelerations at different speeds (4.7-12.7 ms-1) on a training race track. The hoof deceleration is suggested to be divided into two parts. The first is characterized by large impact peak that is mainly attenuated distal to the fetlock joint. The second part is characterized by the onset of loading of the fetlock joint and the following rapid movements of distal bone segments, and the interaction between the ground surface and the hoof. The loading rate and the magnitude of the horizontal peak decelerations increase with speed and with a higher friction between the ground and hoof. The results improve the knowledge of the shock absorbing capacity of the equine limb and the mechanisms behind indicators of mechanical stress to the limb

Dental home care in dogs - a questionnaire study among Swedish dog owners, veterinarians and veterinary nurses

Background: Periodontal disease remains one of the dog's most common health issues, even though it is largely preventable by tooth brushing. Implementation of daily tooth brushing would not only improve animal welfare, but also reduce veterinary costs for the owner. There is a paucity of studies investigating attitudes, opinions and practices of dog owners, veterinarians, and veterinary nurses regarding preventative dental home care in dogs. The objective of this study was to investigate these parameters in Sweden, thereby providing a basis for improved prophylactic strategies. Methods: Validated questionnaire surveys were distributed to all Swedish dog owners (n = 209,263), veterinarians (n = 3657) and veterinary nurses (n = 1650) with e-mail addresses in the national registry. The response rates were 32% for dog owners and veterinarians, and 38% for veterinary nurses. The survey questions concerned attitudes, opinions and practices regarding dental home care, including whether dog owners received information concerning dental home care or not, and if this information resulted in implementation. Results: Attitudes, opinions and practices regarding dental home care are presented for Swedish dog owners, veterinarians, and veterinary nurses. A fundamental finding was that the absolute majority of Swedish dog owners do not perform adequate prophylactic dental home care. Considerable discrepancies were identified in the opinions of veterinary health practitioners and dog owners regarding attitudes towards dental home care and conveying of information. Several areas for improvement in the communication between dog owners and veterinary health practitioners concerning dental home care were identified. Conclusion: Our results illustrates the need for validated methods to increase dog owner compliance with dental home care recommendations. We also see a need of further education, regarding canine dental home care, among veterinarians, veterinary nurses, and dog owners. The results from this unique study constitute an important foundation for future development of prophylactic strategies, with the ultimate goal to improve dental health, and thereby animal welfare, in dogs

Dog Owners' Perspectives on Canine Dental Health - A Questionnaire Study in Sweden

Periodontal disease is one of the most common diseases affecting dogs, with a reported prevalence of at least 80% in dogs over 3 years of age. However, there is a lack of studies regarding dog owners' assessment of their dog's dental health, and whether they perceive clinical signs often associated with periodontal disease, i.e., dental calculus, halitosis or mobile or lost teeth. A validated questionnaire survey was distributed to all Swedish dog owners with email addresses in the national registry (n= 209,263). The response rate was 32%. The survey questions concerned opinions and practices regarding canine dental health, including assessment of dental health parameters and dog owners' ability to examine their dog's mouth. A construct (alpha = 0.76) was used to investigate dog owners' assessed symptoms of their dog's dental health in relation to background factors. Half of the respondents rated their dog's dental health as very good. However, one in four dog owners experienced difficulties when inspecting the dog's teeth. The most common reason for this difficulty was stated to be an uncooperative dog. Almost half of the dog owners reported halitosis to some degree in their dog, and almost four in ten owners reported dental calculus. One in eight dogs had been previously anesthetized for dental cleaning, and one in 12 dogs had experienced problems with gum disease, according to the owners. Owners' assessment varied significantly with the dog's age, weight, breed, breed group, sex, and concurrent disease. Owner-related factors that influenced the assessment of the dog's dental health were age, gender, education, county (urban/rural), and whether they were breeders or not. Dog owners with smaller dogs, older dogs and certain breeds predisposed to periodontal disease assessed their dog's dental health as worse than their counterparts, which is in agreement with previously reported higher prevalence of dental disease in these groups. This indicates that dog owners are able to perform relative assessment of their dog's dental health status. Our results also highlight the need for routine professional assessment of periodontal health, as well as education of dog owners and training of dogs to accept dental care procedures

Professional dental cleaning in dogs: clinical routines among Swedish veterinarians and veterinary nurses

Background Dental disease is very common in dogs and veterinary professional dental cleaning and examination, together with daily dental home care, is the foundation for good dental health. To our knowledge, no previous study has investigated professional dental cleaning routines in small animal veterinary practice. A validated questionnaire survey was distributed to all veterinarians and veterinary nurses with registered e-mail addresses in the Swedish national registry (veterinarians; n = 3657, veterinary nurses; n = 1650). Response rates were 32% for veterinarians (V) and 38% for veterinary nurses (VN). Results In total, 73% (V)/96% (VN) of respondents reported that professional dental cleaning was performed at their work place under general anesthesia, and 27% (V)/18% (VN) that dental cleaning was performed under sedation. Of the respondents, 43% (V)/96% (VN) considered regular dental cleaning under general anesthesia fairly or very important, and 49% (V)/47% (VN) stated that it was sometimes important for good dental health in dogs. A majority of respondents, 84% (V)/97% (VN), reported that dental extractions were performed at their clinic, and 72% (V)/90% (VN) had access to dental radiography equipment. Conclusion A majority of Swedish veterinarians and veterinary nurses perform professional dental cleaning under general anesthesia with access to dental radiography equipment, in accordance with national and international recommendations. However, a considerable proportion of professional dental cleanings were performed under sedation only, and extractions performed without access to dental radiography equipment were common, suggesting several areas of improvement in the routines in Swedish veterinary clinics and hospitals. Our results clearly indicate the need for improved educational efforts to increase the awareness among veterinary health professionals regarding guidelines and official recommendations in canine dental care

Validation of distal limb mounted inertial measurement unit sensors for stride detection in Warmblood horses at walk and trot

Background: Inertial measurement unit (IMU) sensor-based techniques are becoming more popular in horses as a tool for objective locomotor assessment. Objectives: To describe, evaluate and validate a method of stride detection and quantification at walk and trot using distal limb mounted IMU sensors. Study design: Prospective validation study comparing IMU sensors and motion capture with force plate data. Methods: A total of seven Warmblood horses equipped with metacarpal/metatarsal IMU sensors and reflective markers for motion capture were hand walked and trotted over a force plate. Using four custom built algorithms hoof-on/hoof-off timing over the force plate were calculated for each trial from the IMU data. Accuracy of the computed parameters was calculated as the mean difference in milliseconds between the IMU or motion capture generated data and the data from the force plate, precision as the s.d. of these differences and percentage of error with accuracy of the calculated parameter as a percentage of the force plate stance duration. Results: Accuracy, precision and percentage of error of the best performing IMU algorithm for stance duration at walk were 28.5, 31.6 ms and 3.7% for the forelimbs and -5.5, 20.1 ms and -0.8% for the hindlimbs, respectively. At trot the best performing algorithm achieved accuracy, precision and percentage of error of -27.6/8.8 ms/-8.4% for the forelimbs and 6.3/33.5 ms/9.1% for the hindlimbs. Main limitations: The described algorithms have not been assessed on different surfaces. Conclusions: Inertial measurement unit technology can be used to determine temporal kinematic stride variables at walk and trot justifying its use in gait and performance analysis. However, precision of the method may not be sufficient to detect all possible lameness-related changes. These data seem promising enough to warrant further research to evaluate whether this approach will be useful for appraising the majority of clinically relevant gait changes encountered in practice

Ground Reaction Forces: The Sine Qua Non of Legged Locomotion

Legged locomotion results from the feet pressing against the ground to generate ground reaction forces (GRFs) that are responsible for moving the body. By changing limb coordination patterns and muscle forces, the GRFs are adjusted to allow the horse to move in different gaits, speeds, and directions with appropriate balance and self-carriage. This article describes the typical GRF patterns in each gait, the adaptations that produce turning, and the GRF patterns used to unload the painful limb when the horse is lame. The intent is to provide information that is of practical interest and value to equine scientists rather than being a comprehensive review of the topic. [Abstract copyright: Copyright © 2019 Elsevier Inc. All rights reserved.

Functional Locomotor Consequences of Uneven Forefeet for Trot Symmetry in Individual Riding Horses

ABSTRACT: Left-right symmetrical distal limb conformation can be an important prerequisite for a successful performance, and it is often hypothesized that asymmetric or uneven feet are important enhancing factors for the development of lameness. On a population level, it has been demonstrated that uneven footed horses are retiring earlier from elite level competition, but the biomechanical consequences are not yet known. The objectives of this study were to compare the functional locomotor asymmetries of horses with uneven to those with even feet. Hoof kinetics and distal limb kinematics were collected from horses (n = 34) at trot. Dorsal hoof wall angle was used to classify horses as even or uneven (1.5° difference between forefeet respectively) and individual feet as flat (55°). Functional kinetic parameters were compared between even and uneven forefeet using MANOVA followed by ANOVA. The relative influences of differences in hoof angle between the forefeet and of absolute hoof angle on functional parameters were analysed using multiple regression analysis (P<0.05). In horses with uneven feet, the side with the flatter foot showed a significantly larger maximal horizontal braking and vertical ground reaction force, a larger vertical fetlock displacement and a suppler fetlock spring. The foot with a steeper hoof angle was linearly correlated with an earlier braking-propulsion transition. The conformational differences between both forefeet were more important for loading characteristics than the individual foot conformation of each individual horse. The differences in vertical force and braking force between uneven forefeet could imply either an asymmetrical loading pattern without a pathological component or a subclinical lameness as a result of a pathological development in the steeper foot

Comparing subjective and objective evaluation of show jumping competition and warm-up arena surfaces

The development of safety and quality standards for equestrian surfaces needs to be based on objective, repeatable measurements which allow comparisons between surfaces. These measurements should incorporate the assessment of surface performance by riders. This study provides data from objective and subjective assessment of functional properties of high-level show jumping competition and warm-up arenas. Twenty-five arenas in nine international show jumping events were evaluated by mechanical insitu testing with a surface tester, rider assessments using visual analogue scales (198 riders provided 749 arena evaluations), descriptions of arena constructions and by laboratory tests of surface material. Mixed models were used to present subjective evaluation of rider perception of the functional properties for each arena while controlling for rider and event. The association between objective and subjective assessments were also explored creating mixed models, controlling for rider and event. Mechanical measurements of impact firmness, and to a lesser extent cushioning and grip, had a significant positive association with the riders’ perception. Responsiveness as assessed by the Orono biomechanical surface tester (OBST) was negatively associated with the riders’ perceptions, which suggests riders and the OBST had different concepts of this functional property and that further developments of the OBST might be necessary. Objectively measured uniformity showed no useful association with riders’ perception. Even though arena assessments were made by top level riders, a substantial inter-rider variation was demonstrated