Bite and kick injuries in horses: prevalence, risk factors and prevention

Associations between turn out practices and rates of musculoskeletal disease and injury in Thoroughbred foals and yearlings on stud farms in the United Kingdom

BACKGROUND

Early-life locomotor activity during turn out may alter susceptibility to musculoskeletal disease and injury via modulation of behaviours and tissue development during growth.

OBJECTIVES

Investigate associations between turn out practices and rates of musculoskeletal disease and injury in young Thoroughbreds on stud farms in the United Kingdom.

STUDY DESIGN

Prospective cohort.

METHODS

Daily records were kept on location and duration of turn out for 134 Thoroughbred foals on six stud farms, from birth until leaving the farm or study exit. Data on veterinary-attended episodes of musculoskeletal disease or injury were collated concurrently. Average daily turn out times (hours), areas (acres) and group size (n foals) were calculated for rolling 7- and 30-day periods of age. Multivariable Cox regression, including farm as a random effect, was used to investigate associations between turn out practices and musculoskeletal disease and injury.

RESULTS

The overall incidence of musculoskeletal disease or injury was 5.3 cases/100 foal-months at risk (95% confidence interval [CI]: 4.2-6.6). Compared with 24/7 turn out, average daily turn out times of between 9 and 23 hours over a 7-day period were associated with a 4.6-fold increase in musculoskeletal injury rate (95% CI: 1.7-12.3; P < 0.001), adjusting for farm and paddock area. Each 1-acre increase in the average daily turn out area during the 4th month of life, reduced the rate of musculoskeletal disease and injury between 6 and 18 months of age by 24% (hazard ratio 0.76, 95% CI: 0.58-0.99; P < 0.001), adjusting for farm and turn out time.

MAIN LIMITATIONS

Non-random sample of participants may affect generalisability. Use of veterinary-attended events likely underestimates disease/injury rates.

CONCLUSIONS

Results suggest that disruptions or alterations to turn out time routines increase injury risk and should be avoided where possible. Turn out in larger paddocks, particularly before weaning, may confer protection against subsequent musculoskeletal disease and injury.

Are Users Good Assessors of Social Dominance in Domestic Horses?

Horse users and caretakers must be aware of the risks of mixing social groups. The current study investigated whether eight equine practitioners can assess the social dominance rank of 20 horses. The horses' feeding time and agonistic/aggressive and submissive behaviours were observed during the feed confrontation test, and the dominance index (DI) was calculated. Kendal's W, Spearman correlations and factor analysis were applied to test the raters' agreement, the relationship between dominance ranks and the behavioural variables, and to determine the clustered behaviours. The agreement between all raters in the classification of dominance order ranged from moderate to perfect. The ranking by every rater was strongly and negatively correlated with the time of eating in feed confrontation tests and with the DI, evidencing shorter feeding times for more submissive horses. The withdrawal of the horse when threatened was the behavioural variable that was most often correlated with raters' ranking. The current study confirmed the abilities of practitioners to categorise the horses under their care according to their social interactions. Additionally, rolling when denied access to feed was proposed as frustration-releasing (redirected) behaviour.

Health of Polo Horses

This literature review analyzes the historical development of polo, its organizational structure, the course of the game, as well as the breeding, rearing, and training practices of polo horses. Frequently occurring ailments, such as musculoskeletal injuries, respiratory diseases, and internal illnesses, are highlighted. Lameness is a major problem, with injuries to the superficial digital flexor tendon being the most common cause. Other notable diseases include exercise-induced pulmonary hemorrhage (EIPH), myositis, rhabdomyolysis, and equine infectious anemia (EIA). To ensure the welfare of polo horses, effective prevention and management strategies are crucial. These include proper training, the adaptation of the ground surface, appropriate shoeing, and compliance with animal welfare guidelines and association rules. Collaboration between associations, players, organizers, and veterinarians is crucial. Promoting responsible management practices and raising awareness among stakeholders can help ensure that polo continues to thrive while maintaining high animal welfare standards.

A field approach to observing changes in behavioural welfare indicators over 2 years in stabled horses

In stabled horses, several behaviours are considered to be important indicators of the state of welfare at the individual level: stereotypies, aggressive behaviours towards humans and the "withdrawn", alert, sternal, lateral and observation postures. Until now, these behaviours have been extensively studied in relation to different horse management practices. However, little is known about their changes or consistency over time. This study aimed to investigate differences in the expression of these behaviours assessed on 44 stabled horses during an initial 3-month period and then again on the same individuals 2 years later. Out of the six behaviours studied, two showed significant differences between the 2 years with medium effect sizes: the levels of aggressiveness towards humans increased (Wilcoxon signed-rank test: V = 65, P = 0.005) and those of recumbent rest during the day decreased (V = 416, P < 0.001) over time. The results also suggested limited evidence of major changes over time in the expression of stereotypies, the "withdrawn", alert and observation postures. However, the principal component analyses carried out on all the behaviours showed that alert and observation postures may slightly decrease over time for some individuals. Regarding stereotypies and the "withdrawn" posture, the results mainly suggested a change at the individual level in the expression of these behaviours over time. This study provided new insights into the dynamic nature of several behaviours when the horses' living conditions are not fundamentally altered and raised hypotheses about the state of welfare of stabled individuals over a 2-year period.

Frequency and nature of health issues among horses housed in an active open barn compared to single boxes-A field study

BACKGROUND

Keeping horses in open barns has positive effects on social interaction and free movement, which may improve horse welfare. However, many horse owners fear that housing in open barns leads to more injuries.

OBJECTIVE

To compare health events among horses housed in an active open barn (AOB) or in single boxes (BOX).

STUDY DESIGN

A prospective study during 9 months and a 2-year retrospective study.

METHODS

Two housing systems in one farm were investigated: AOB and BOX in pairs or alone in paddock (2-4 h/day) using 66 and 69 horses in the prospective respectively retrospective study. Lameness, wounds, colic and days lost from training were recorded.

RESULTS

There were lower prevalences of lameness and colic in AOB than in BOX (18% vs. 26% and 0% vs. 5%; p < 0.001). Overall, there was a larger proportion of individuals with health events in AOB (83%) compared with BOX (52%) (p < 0.01). However, number of days lost to training did not differ between AOB (10 ± 15 days) and BOX (15 ± 34 days) (p = 0.36). There were no significant differences between the housing systems in number of health events/horse in the retrospective study: AOB 1.54 ± 1.51 versus BOX 1.14 ± 1.20 (p = 0.22).

MAIN LIMITATIONS

The different, not standardised, housing systems varied in size and number of horses with no individual consideration in this descriptive field study with no possibility to cross-over. A convenience sample was used.

CONCLUSIONS

Lameness and colic were less frequent in the AOB system compared to single boxes, probably because the horses in the open barn could move freely day and night. Horses in AOB had a higher prevalence of wounds due to interactions between horses, but this did not lead to more days lost from training.

Use of antimicrobials licensed for systemic administration in UK equine practice

BACKGROUND

Judicious antimicrobial use (AMU) is important for preserving therapeutic effectiveness. Large-scale studies of antimicrobial prescribing can provide clinical benchmarks and help identify opportunities for improved stewardship.

OBJECTIVES

To describe systemic AMU in UK equine practice and identify factors associated with systemic and Category B (third and fourth generation cephalosporins, quinolones and polymixins) AMU.

STUDY DESIGN

Retrospective cohort.

METHODS

Anonymised electronic patient records (EPRs) for all equids attended by 39 UK veterinary practices between 1 January and 31 December 2018 were collected via the VetCompass programme. Systemic antimicrobial prescriptions were identified using electronic keyword searches. Indications for AMU were determined through manual review of a randomly selected subset of EPRs. The types and frequency of systemic antimicrobials prescribed and indications were summarised using descriptive statistics. Mixed-effects logistic regression was used to evaluate practice- and horse-related risk factors.

RESULTS

Systemic antimicrobials were prescribed to 12 538 (19.5%, 95% confidence interval [CI]: 19.2%-19.8%) of 64 322 equids attended in 2018. Category B antimicrobials were prescribed to 1.9% (95% CI: 1.8%-2.0%) of attended equids and in 8.9% (95% CI: 8.5%-9.4%) of antimicrobial courses. Bacteriological culture was performed in 19.1% (95% CI: 17.1%-21.3%) of Category B antimicrobial courses. The most commonly prescribed antimicrobial classes were potentiated sulphonamides (50.2% of equids receiving antimicrobials) and tetracyclines (33.5% of equids receiving antimicrobials). Integumentary disorders were the most common reason for systemic AMU (40.5% of courses). Urogenital disorders were the most common reason for Category B AMU (31.1% of courses). Increased odds of systemic and Category B AMU were observed in equids <1 year compared with those aged 5-14 years. Breed was associated with AMU, with odds of systemic and Category B AMU highest in Thoroughbreds and Thoroughbred crosses.

MAIN LIMITATIONS

Convenience sample of practices may limit generalisability.

CONCLUSIONS

Empirical use of Category B antimicrobials remains commonplace.

Does Feeding Management Make a Difference to Behavioural Activities and Welfare of Horses Reared for Meat Production?

Horses reared for meat production are generally fed a diet rich in starch with the aim of maximizing production performances. This study evaluated the effects of two feeding management systems on horse welfare by analysing the relative time spent engaged in different behavioural activities. Nineteen Bardigiano horses aged 14.3 ± 0.7 months were randomly assigned to one of two group pens: one group was fed high amounts of starch-rich concentrates (HCG; n = 10), the other was fed a fibre-based diet (HFG; n = 9). Behavioural activities performed by each horse were video-recorded over a 96-h period. A scan sampling process (n = 144 scans/horse/day; total n of scans sampled = 10,368) was used, and the scans were analysed according to a specific ethogram. The mean frequency (%/24 h) spent exhibiting each behavioural activity was calculated to obtain the time budget. After checking for normality (Shapiro–Wilk test), Student’s t tests (normally distributed data) and Mann–Whitney tests (not normally distributed data) were used to compare the time budgets of the two groups of horses (HCG vs. HFG). Principal Component Analysis (PCA) was applied to identify the components explaining the variability in behavioural activities between the two groups. K-means cluster analysis subsequently confirmed the PCA results. The behavioural activities associated with feeding horses a fibre-based diet correlated with better horse welfare compared with feeding horses a starch-based diet. Feeding horses a fibre-based diet resulted advantageous from both the welfare and economic perspective; it allowed horses to spend more time expressing feeding behaviours and reduced energy expenditure in the form of excitable, or “fizzy”, behaviours.

Basic Needs in Horses?-A Literature Review

Simple Summary

All animals have requirements that are essential for their welfare, and when these basic needs are not met, the animal suffers. In horses, it is claimed that these needs include social contact, social companionship, free movement and access to roughage in the form of grass, hay and/or straw. To validate this claim, this review examines 38 studies that reported on horses’ responses when one or more of these factors are restricted. We categorised the type of responses investigated: (a) Stress (e.g., increased stress hormones), (b) Active (e.g., increased aggression), (c) Passive (e.g., depressive-like behaviour) and (d) Abnormal Behaviour (e.g., stereotypies), and analysed the frequencies with which the investigated responses were shown. Overall, the studies reported that horses did react to restrictions in the described basic needs, especially to combinations of restricted social contact, free movement and access to roughage. The observation of passive responses and the development of abnormal behaviour provided compelling evidence that horses were suffering under these restrictions, and existing abnormal behaviours indicated that they had suffered at some time in the past. We conclude that the literature supports the claim that social contact, free movement and access to roughage are basic needs in horses and need to be taken into consideration to ensure their mental and physical welfare in management and training.

Abstract

Every animal species has particular environmental requirements that are essential for its welfare, and when these so-called “basic needs” are not fulfilled, the animals suffer. The basic needs of horses have been claimed to be social contact, social companionship, free movement and access to roughage. To assess whether horses suffer when one or more of the four proposed basic needs are restricted, we examined several studies (n = 38) that reported behavioural and physiological reactions to these restrictions. We assigned the studies according to the four types of responses investigated: (a) Stress, (b) Active, (c) Passive, and (d) Abnormal Behaviour. Furthermore, the number of studies indicating that horses reacted to the restrictions were compared with the number of studies reporting no reaction. The limited number of studies available on single management restrictions did not allow conclusions to be drawn on the effect of each restriction separately, especially in the case of social companionship. However, when combinations of social contact, free movement and access to roughage were restricted, many of the horses had developed responses consistent with suffering. Passive Responses, indicating acute suffering, and Abnormal Behaviour, indicating suffering currently or at some time in the past, were especially clearly demonstrated. This provides further evidence of the usefulness of assessing behavioural parameters in combination with physiological measurements when evaluating horse welfare. This meta-analysis of the literature confirms that it is justified to claim that social contact, free movement and access to roughage are basic needs in horses.

Text Mining Analysis to Evaluate Stakeholders' Perception Regarding Welfare of Equines, Small Ruminants, and Turkeys

Welfare of animals significantly depends on how stakeholders perceive their needs and behave in a way to favor production systems that promote better welfare outcomes. This study aimed at investigating stakeholders' perception of the welfare of equines, small ruminants, and turkeys using text mining analysis. A survey composed by open-ended questions referring to different aspects of animal welfare was carried out. Text mining analysis was performed. A total of 270 surveys were filled out (horses = 122, sheep = 81, goats = 36, turkeys = 18, donkeys = 13). The respondents (41% veterinarians) came from 32 different countries. To describe welfare requirements, the words "feeding" and "water" were the most frequently used in all the species, meaning that respondents considered the welfare principle "good feeding" as the most relevant. The word "environment" was considered particularly important for turkeys, as well as the word "dry", never mentioned for other species. Horses stakeholders also considered "exercise" and "proper training" important. Goat stakeholders' concerns are often expressed by the word "space", probably because goats are often intensively managed in industrialized countries. Although the sample was too small to be representative, text mining analysis seems to be a promising method to investigate stakeholders' perception of animal welfare, as it emphasizes their real perception, without the constraints deriving by close-ended questions.

Autopsy Features of Fatal Donkey Attack

Lethal donkey attacks have very rarely been described. The case of a 65-year-old man who was found deceased on a country road with 2 domestic donkeys nearby is, therefore, reported. Examination of the body revealed contusions and lacerations of the face and scalp, a comminuted fracture of the left maxilla, comminuted fracturing of the right radius and ulna and of the left anterior superior iliac spine, a flail chest, and pulmonary contusions. In addition, there were bite marks on the left thigh, right buttock, right axilla/upper arm, and left cheek which corresponded to the dental arcades of the donkeys. Death had resulted from blunt chest trauma due to an attack by 1 or 2 donkeys. Deaths and serious injuries are much more commonly caused by horses; however, this case shows that even domesticated donkeys may also rarely be capable of inflicting significant trauma and so should be approached with circumspection.

Epidemiology of fractures: The role of kick injuries in equine fractures

BACKGROUND

Fractures occur commonly in equids and often are associated with complications and a poor outcome. There are no reports on the epidemiology of fractures in a heterogeneous equine population.

OBJECTIVES

To study the epidemiology of fractures in a heterogeneous equine population, focusing on differences between fractures resulting from a kick and fractures, resulting from other causes and investigating predictors for recovery.

STUDY DESIGN

Retrospective case series.

METHODS

Data of all equids presented to the Equine Department, Vetsuisse Faculty, University of Zurich between 1990 and 2014 and diagnosed with a fracture were reviewed and those with a known cause were included in this study. Mann-Whitney and chi-squared tests were used to compare recovery rates of fractures resulting from a kick and fractures resulting from other causes, and a logistic regression was carried out for multivariate analysis of the most important factors affecting recovery.

RESULTS

Here, 1144 cases fulfilled the inclusion criteria. Of all fractures (with a known cause), 43.6% were the result of a kick from another equid. Kicks often produced open fractures (44.7%) that involved bones of the limbs (85.6%). Overall recovery was 70.1%. Logistic regression showed that high-grade lameness accompanying the fracture and severe comminution negatively affected recovery.

MAIN LIMITATIONS

The equids in this study were drawn from a referred population, which likely precluded the inclusion of both minor fractures and catastrophic fractures that necessitated immediate euthanasia. Moreover, many cases were excluded because the cause of the fracture could not be determined from the patient record.

CONCLUSIONS

Kicks are the most common cause of fractures in a heterogeneous equine population and measures to reduce the incidence of kicks are necessary in group-housing systems.

Influence of Paddock Size on Social Relationships in Domestic Horses

The aim of this study was to explore whether the size of paddocks affected social interactions within a group of horses. Furthermore, the effects of the gender composition in groups on social behavior were investigated. The research was done in a horse-riding center. A total of 78 horses and ponies, forming 3 groups, were included in the study. The time of the observation was divided into 2 periods. The data obtained from the 1st period (the horses were on relatively small paddocks) and the 2nd period (the paddocks were significantly bigger) were compared. The findings uniformly indicated that an enlargement of grass paddocks resulted in a significant decline in the number of social interactions, both agonistic and play types, in all studied herds. A likely principal reason for a change in the number of social interactions seems to be feeding management and how it changed between seasons, rather than paddock size. No effect of group composition on social interaction was found in terms of aggressive interaction, and only 1 group differed regarding friendly interaction.

A Nordic survey of management practices and owners' attitudes towards keeping horses in groups

Keeping horses in groups is widely recommended but limited information is available about how this is implemented in practice. The aim of this survey was to describe how horses are kept in the Nordic countries in relation to sex, age, breed, and equestrian discipline and to assess owners' attitudes toward keeping horses in groups. Horse owners in Denmark, Finland, Norway, and Sweden were approached using a web-based questionnaire, which was translated into 4 languages and distributed online via equestrian forums, organizations, and social media. The number of respondents was 3,229, taking care of 17,248 horses. Only 8% of horses were never kept in groups, 47% were permanently grouped for 24 h/d, and 45% were stabled singly but grouped during turnout. Yearlings were most often permanently kept in groups (75%), mares and geldings more commonly during parts of the day (50 and 51%, respectively), and stallions were often kept alone (38%). Icelandic horses were more likely to be permanently kept in groups (36%) than warmbloods (16%) and ponies (15%). Twice as many competition horses (51%) were never grouped compared with horses used for breeding (20%) or leisure purposes (15%). The majority of respondents (86%) strongly agreed that group housing benefits horse welfare and that it is important for horses to have the company of conspecifics (92%). Nevertheless, not all horses were kept in groups, showing that attitudes toward group housing may not necessarily reflect current management. The risk of injury was a concern of many respondents (45%), as was introducing unfamiliar horses into already established groups (40%) and challenges in relation to feeding in groups (44%). Safety of people (23%) and difficulties handling group-kept horses (19%) were regarded as less problematic. Results suggest that the majority of horses have the possibility to freely interact with other horses, either as fulltime members of a group during 24 h/d or during turnout. Future research should address the extent to which being a part-time member of a group affects horse welfare. For permanent group housing to become more widespread, such as it is the case for most farm animals, future research could focus on solving some of the reoccurring problems perceived with keeping horses in groups. The dissemination of evidence-based information on all aspects around keeping horses in groups can ultimately stimulate further positive changes in the management of group-kept horses.

Reliability of an injury scoring system for horses

Background

The risk of injuries is of major concern when keeping horses in groups and there is a need for a system to record external injuries in a standardised and simple way. The objective of this study, therefore, was to develop and validate a system for injury recording in horses and to test its reliability and feasibility under field conditions.

Methods

Injuries were classified into five categories according to severity. The scoring system was tested for intra- and inter-observer agreement as well as agreement with a 'golden standard' (diagnosis established by a veterinarian). The scoring was done by 43 agricultural students who classified 40 photographs presented to them twice in a random order, 10 days apart. Attribute agreement analysis was performed using Kendall's coefficient of concordance (Kendall's W), Kendall's correlation coefficient (Kendall's τ) and Fleiss' kappa. The system was also tested on a sample of 100 horses kept in groups where injury location was recorded as well.

Results

Intra-observer agreement showed Kendall's W ranging from 0.94 to 0.99 and 86% of observers had kappa values above 0.66 (substantial agreement). Inter-observer agreement had an overall Kendall's W of 0.91 and the mean kappa value was 0.59 (moderate). Agreement for all observers versus the 'golden standard' had Kendall's τ of 0.88 and the mean kappa value was 0.66 (substantial). The system was easy to use for trained persons under field conditions. Injuries of the more serious categories were not found in the field trial.

Conclusion

The proposed injury scoring system is easy to learn and use also for people without a veterinary education, it shows high reliability, and it is clinically useful. The injury scoring system could be a valuable tool in future clinical and epidemiological studies.