Observational studies in horses involve systematically assessing and recording behaviors, conditions, or other characteristics without manipulating the study environment. These studies provide insights into natural equine behaviors, health conditions, and interactions with their environment. Researchers often focus on aspects such as herd dynamics, feeding patterns, or responses to environmental changes. The data collected can help identify trends, correlations, and potential risk factors for certain conditions. This page compiles peer-reviewed research studies and scholarly articles that explore various observational methodologies and their applications in understanding equine behavior and health.
ADAMS KM.The ciliate population of the large intestine of the horse shows large, daily variations. The ventral colon is the site where the ciliate fauna varies most. Two species, Cycloposthium edentatum and C. dentiferum, became established in the large intestine after passage through the stomach and small intestine. The introduction of new species into the ventral colon caused significant changes in the fauna of that part of the gut.
LEVINE L, WYMAN L, CHEN BL, MURPHY J.1. A method is presented for estimating the relative reactivity with respect to horse serum of antitoxins processed from horse plasma, by observing skin reactions of sensitized rabbits.
2. It is feasible to test 4 preparations, each on 3 rabbits, with standard fiducial limits of from 53% to 188% of the true value.
3. As the sensitizing dose was increased, the relative reactivity of a given test material appeared greater. The function was asymptotic at higher dose levels.
4. The greater the sensitizing dose, the smaller was the variance of the relative reactivity within its replicates.
5. M...
Back pain is the cause of bad welfare in humans and animals. Although vertebral problems are regularly reported on riding horses, these problems are not always identified nor noticed enough to prevent these horses to be used for work. Results: Nineteen horses from two riding centres were submitted to chiropractic examinations performed by an experienced chiropractor and both horses' and riders' postures were observed during a riding lesson. The results show that 74% of horses were severely affected by vertebral problems, while only 26% were mildly or not affected. The degree of vertebral probl...
This study presents the validation of two recently described pain scales, the Equine Utrecht University Scale for Composite Pain Assessment (EQUUS-COMPASS) and the Equine Utrecht University Scale for Facial Assessment of Pain (EQUUS-FAP), in horses with acute colic. A follow-up cohort study of 46 adult horses (n = 23 with acute colic; n = 23 healthy control horses) was performed for validation and refinement of the constructed scales. Both pain scales showed statistically significant differences between horses with colic and healthy control horses, and between horses with colic that co...
Warm-season grasses (WSG) incorporated into traditional cool-season rotational grazing systems to increase summer yields are typically established in monoculture in separate pasture areas. Few studies have evaluated alternative interseeded establishment of WSG, despite potential benefits for improving biodiversity and land-use efficiency. The objective of this study was to determine the impact of establishment method (monoculture vs. interseeded) on crabgrass pasture forage yield, nutritive value, and preference under equine grazing. Three adult standardbred mares grazed two main plots on two ...
To determine the causes of horse-related injuries in a rural western community. Methods: Prospective identification of persons with horse-related injuries and retrospective interviews with patients or witnesses to determine causes. Methods: A small rural community in Alberta where the western style of riding predominates. Methods: All patients presenting to two family medicine clinics or to the Sundre General Hospital emergency department. Methods: Factors contributing to the injury as recalled by patients or witnesses, and characteristics of the persons, horses, and injuries. Results: Two thi...
Häussling MPP, Steinberg T, Büttner K, Hannig C, Hannig M, Lemke L, Zierau O, Staszyk C.Destructive lesions of the peripheral and infundibular cementum are increasingly recognized in equine dentistry. While similarities to human caries have been noted, current evidence does not conclusively support this classification. This study aims to assess the prevalence, distribution, and potential risk factors associated with these lesions in a defined horse population. Unassigned: A total of 114 horses from northern Germany underwent standardized oral examination between 2021 and 2023. Clinical data on peripheral and infundibular lesions, diastemata, and influencing factors such as age an...
Fernández-Villa C, Miranda M, Rigueira L, Martinez L, Villanueva B, Freire S, López-Alonso M.Serum mineral concentrations are key indicators of nutritional status, metabolic function and health in horses; however, contemporary reference intervals (RI) derived from large, well-characterised populations remain scarce. Objective: To establish serum RI for macro- and microminerals in clinically healthy horses in Northwestern Spain and to evaluate the influence of sex, age, breed and diet on mineral status. Methods: Blood samples were collected from clinically healthy horses (n = 211), and serum concentrations of essential macrominerals (calcium [Ca]; phosphorous [P]; magnesium [Mg]; sodiu...
Alonso MA, Dos Santos GR, Fonte JS, Marques PC, Pereira DD, Toral FLB, Bordignon V, Junior JB, Squires E, Fernandes CB.This retrospective study evaluated whether different reproductive biotechnologies influence neonatal behaviour parameters in foals. Data from 102 foalings in two commercial breeding farms were analysed, including foals conceived by artificial insemination (AI), conventional embryo transfer (ET) and intracytoplasmic sperm injection (ICSI). Neonatal parameters recorded were birth weight, time to achieve sternal recumbency, time to stand, time to nurse and time to meconium elimination. Mixed statistical models were applied to assess the influence of reproductive technique, breed, sex and farm. Si...
Cottone A, Seiter K, Thomas B, Schank N, Wulf M, Miller L, Anderson S, Munkhsaikhan U, Verma A, Abidi AH, Kassan M.Colic remains one of the most frequent and costly causes of equine morbidity and mortality, with significant welfare and economic implications. Disturbances in the gut microbiome are increasingly recognized as an important contributing factor. In recent years, prebiotics, non-digestible substrates that promote beneficial microbes, have emerged as promising microbiome-targeted strategies. () has gained attention for its unique ability to degrade mucin, maintain epithelial integrity, and exert potent anti-inflammatory effects. Although its benefits are well established in humans and rodent mode...
Hiney K, Anderson K, Brady C.Accurate interpretation of affective state (AS) of animals is critical to assessment of their wellbeing. Although horse owners may appreciate the importance of this skill, many lack the ability to interpret AS accurately. Objective: To test if the online course Recognizing Affective States in Equine (RAiSE) improves participants' assessment of AS in horses and increases use of AS in management. Methods: Participants completed pre (PRE), post (POST), and 90 day post (90POST) course surveys to assess accuracy in identifying AS in 20 videos, as well as use of AS in their horse interactions. Pre/p...
Czerner AC, Lindner A, Zeyner A, Wensch-Dorendorf M, Gehlen H.Changes in horse management and use mean that a growing number of horses are now kept into older age, while age-specific management practices for these animals remain insufficiently documented. This cross-sectional online survey aimed to describe the housing, feeding, activity, behaviour and care routines of horses aged 20 years and older in Germany, based on 923 questionnaires completed by horse owners about their senior horses. Most horses maintained regular tactile social contact (87.4%, = 805), and over half were still ridden or driven (61.6%, = 566). However, the proportion of horses in...
Watson WL, MacKay JRD, Dwyer CM.This study focuses on recreational horse owners in the UK and Ireland to explore the relationship between horse characteristics and welfare issues. An online questionnaire was distributed to 1501 horse owners to collect data on the owners, horses, and health/behavioural issues. Most respondents were female (98%), lived in England (56%), and did not insure their horses for veterinary costs (51%). Horses were typically over 5 years of age (96%), taller than 154 cm (55%), and mostly geldings (65%). Common welfare issues reported included lameness (26%), handling problems (11%), antisocial behavio...
Volding DM, Flores-Ahlschwede P, Cramer MJ, Landrock KK, Sayre KC, Welsh TH, Bordin AI, Piccione J, Cohen ND.To determine the effects of transfusion of Rhodococcus equi hyperimmune plasma (REHIP) on serum electrolyte and protein concentrations in neonatal foals. Unassigned: A prospective observational study of 355 privately owned Thoroughbred foals from 13 farms in New York and cross-sectional study of REHIP samples. Blood was collected immediately before and after transfusion of either 1 or 2 L of REHIP to foals, and serum samples were separated and frozen until tested for concentrations of sodium (Na), potassium (K), chloride (Cl), total protein (TP), albumin, and globulins. Samples (n = 90) of REH...
Rigby C, Prutton A.Recruitment and retention of equine veterinarians presents an ongoing challenge for employers. Recent research has highlighted factors that contribute to attrition across the profession, but further understanding of the specific challenges faced in the equine sector is needed. This study builds on existing research by exploring the relative impact of different factors on veterinarians' decisions to leave equine clinical practice. Methods: Veterinarians who had left equine clinical practice in the UK within the previous 10 years were invited to participate in an anonymous online survey. The par...
Rey-Conejo R, Toribio RE, Möller S, Müller E, Fores-Jackson P.Insulin dysregulation is a key component of equine metabolic syndrome and is commonly assessed using basal insulin concentrations. Different analyzers may yield variable insulin results, limiting comparability. Objective: To assess the analytical performance of the ADVIA Centaur XPT chemiluminescent immunoassay (CLIA) for equine insulin measurement and to establish adapted decision thresholds based on comparison with a previously used CLIA method. Methods: Precision, linearity, and dilution recovery were assessed for the ADVIA Centaur XPT. A total of 89 equine serum samples submitted for basal...
Gottleib K, Trager-Burns L, Santonastaso A, Bogers S, Werre S, Burns T, Byron C.Differences in horseshoe materials may have effects on gait that could change perceived esthetic qualities. Objective information regarding effects of shoeing on gait characteristics of horses is scant. The aim of this study was to determine differences in gait characteristics for horses under various experimental shoeing conditions (barefoot, aluminum shoes, steel shoes) on two surfaces (asphalt and soft footing) using body- and hoof-mounted sensors. We hypothesized that shoeing would affect hoof arc height during early (arc height a) and late (arc height b) swing phases but would not affect ...
Kovarikova S, Blahova J, Steffenova V, Vaskova N, Jahn P.Currently, there is relatively little published information on the urine protein-to-creatinine (UPC) ratio in horses, a parameter commonly used in dogs and cats. The aim of this study was to determine the reference range of UPC in urine samples of apparently healthy horses and to assess the influence of age and sex. Urinalysis and the determination of urinary protein and creatinine concentrations and ratios were performed. A total of 118 urine samples from apparently healthy horses were included in the study: 10 from foals younger than 6 months and 108 from horses older than 1 year. The median...
de Chaisemartin C, Vandeweerd JM, Schramme M.Comminuted fractures of the proximal phalanx (CFPP) occur in adult horses. Various treatments have been described. It remains uncertain which is the best therapeutic option. Objective: This study aims to review systematically the existing literature on CFPP in horses, evaluate treatment modalities, synthesise outcomes to assess treatment efficacy and survival rates, and identify knowledge gaps for future research. Methods: Scoping review. Methods: A literature search was conducted using online databases. The bias quality of each article was evaluated. Chi-squared analysis was used to detect di...
Paganelli GC, Schott HC.Small intestinal (SI) distension and gastric reflux (GR) are common in horses with mechanical and functional ileus. Removal of GR results in fluid/ion losses. Objective: 1) Determine the capacity of healthy SI; 2) measure ion concentrations in normal SI fluid, GR, or fluid from SI undergoing resection. The authors hypothesized that Na and Cl concentrations would be lower and higher, respectively, in GR as compared to SI fluid from healthy horses, while there would be little difference in K concentration. Methods: Observational study: two to 15 meters of SI from 15 horses were distended with wa...
Janicek JC, Grant BD, Woodie JB, Reed SM, Mariën T, Anderson J.To describe the surgical approach used in horses undergoing C7-T1 ventral interbody fusion using a kerf cut cylinder (KCC) implant and report the short- and long-term outcomes. Methods: Observational retrospective study. Methods: A total of 38 client-owned horses. Methods: Medical records of horses that underwent ventral interbody fusion because of C7-T1 cervical vertebral stenotic myelopathy from 2004 to 2024 were reviewed. Preoperative variables included age, sex, breed, and affected site(s). Surgical variables included types of KCC used, intraoperative complications, and anesthesia related ...
Boije Af Gennäs K, Jungmalm J.Although horse riding is hazardous and injuries are common, young riders regularly engage in horse-related activities. To our knowledge, there have been no syntheses on youth horse-related injuries published during the past decade that employ a multi- and interdisciplinary research agenda (M-IDR) and that incorporate both quantitative and qualitative methods. Therefore, this scoping review aimed to (1) review studies on horse-related injuries among children and adolescents and (2) identify methodological and paradigmatic trends according to M-IDR. Using the Preferred Reporting Items for System...
Avison A, Goderre BG, Pyle WG, Physick-Sheard PW.Sudden cardiac death is common in racehorses. Factors associated with the QT interval that could predispose to fatal cardiac arrhythmias are unknown. Cardiac restitution, expressed as a ratio of QT/TQ, has been used in humans to assess arrhythmia risk but has not been described in horses during maximal intensity exercise. Objective: Describe factors associated with the QT interval and cardiac restitution ratio (CRR) in clinically normal Standardbred racehorses under race-day conditions. Methods: Archival electrocardiograms from 42 Standardbred horses during live racing in Ontario. Methods: Obs...
Baxley BH, Stellato A, Anderson NC.Horses involved in equine-assisted services (EAS) support the psychological and physiological health of individuals through mounted activities; however, limited research exists on how these sessions affect the horse's movement. Objective: This study aimed to investigate the influence of rider presence and posture on horses' gait parameters in EAS settings. Methods: Horses (n = 22) were observed during walk and trot, both with and without a mounted rider, in four EAS centers in the United States. Distal limb-mounted inertial measurement units collected peak ground reaction force (pGRF), stride ...
González-Medina S, Barrett MF, Aboellail TA, Nelson BB, Nout-Lomas YS.While computed tomographic (CT) myelography is increasingly available and has been evaluated in alive horses, objective criteria for diagnosing cervical vertebral compressive myelopathy (CVCM) are lacking. Objective: To establish morphometric dimensions of the cervical vertebral canal and spinal cords from horses with CVCM and compare those to unaffected horses with the use of cone beam CT (CBCT). Methods: Prospective observational study. Methods: Four control horses and ten horses with CVCM underwent diagnostic imaging and histopathology. Morphometric measurements were obtained from cervical ...
Yano R, Moriyama T, Arai H, Scheftgen AJ, Suen G, Nishida T, Handa M, Fukuma N.Colic, a major gastrointestinal disease in horses, has a high recurrence rate and can lead to surgery or fatal outcomes, highlighting the need for effective prevention measures. Disruption of the microbiome is a multifaceted problem and can occur from a variety of factors, such as high-concentrate diets, which can then potentially cause colic. However, individual variation in the incidence of colic can occur when under identical management practices. The aim of this study was to characterize the fecal bacterial composition of Japanese draft horses with and without a history of colic in the pas...
Smith R, Perkins L, Pinchbeck G, Ireland J.The decisions made by horse owners on behalf of their animal, including decisions to involve a veterinarian, play an important role in the management of pain. This study explored horse owners' experiences to understand how they conceptualised chronic pain within the context of their horse-human relationship, what led them to seek veterinary involvement, and how veterinary interactions shaped their perceptions of pain and its management. An ethnographic approach using constructivist grounded theory methods was adopted. This paper draws upon field notes generated through 200 h of observation und...
Hain AM, Tretow M, Bienert-Zeit A.Outside of Iceland, the Icelandic horse is prone to the development of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH). The aim of this study was to determine the radiographic prevalence and clinical signs of EOTRH in elderly horses (≥15 years) in Iceland. The rostral oral cavity of 170 horses (aged 15-30 years) was examined clinically. In addition, husbandry and nutritional management history was recorded by use of a questionnaire. Radiographs (2-4 views) of 188 horses were evaluated, findings were categorized by numerical staging of the condition and collated with clinica...
Mouncey R, de Mestre AM, Verheyen KL.Analyses of industry-level data suggest that around one-third of the UK and Ireland Thoroughbred foal crop fail to enter training. Prospective follow-up of individual horses could provide additional insight, particularly around individuals not attaining specific career milestones. Methods: A Thoroughbred birth cohort was established on stud farms across the UK and Ireland. Training, race performance, sales, export data, destinations and reasons for individuals failing to meet career milestones were collected from stud records, follow-up with owners, stud book and racing authorities' databases,...
