Analyze Diet

Topic:Observational Study

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.
Choice for the horse is paramount: Owners’ experiences in facilitating friends, forage, and freedom in their management practices.
Animal welfare (South Mimms, England)    August 10, 2026   Volume 35 e48 doi: 10.1017/awf.2026.10107
Watson WL, Jessiman LJ, Dwyer C.Owned horses rely on people for their behavioural needs, such as access to conspecifics, constant access to low nutrient density, fibrous forage and freedom of movement; otherwise known as friends, forage and freedom (3Fs). Restricting the 3Fs prevents horses from achieving optimal welfare. We carried out 14 semi-structured interviews in the UK and Ireland to examine horse owners' experiences, attitudes and beliefs around the provision of the 3Fs. Most participants were female, aged from 25 to 65 years, resident in the UK and kept their horse at a livery facility. A reflexive thematic analysis...
Sleep architecture and lying behavior in horses across age groups and two housing systems: an overnight non-invasive EEG study.
Frontiers in veterinary science    August 6, 2026   Volume 13 1898580 doi: 10.3389/fvets.2026.1898580
Zimmer L, Schramel JP, Lyrakis M, Trachsel DS, Auer U, Leschnik M, Macho-Maschler S, Hotz M, Wahl H, Brunner S, Palme R, Cavalleri JV.Sleep is a crucial factor for the well-being of horses, yet assessing equine sleep in common housing conditions remains challenging. This study investigated the effects of changes in horses' immediate environment and the influence of age on their sleep and resting behavior using a novel, non-invasive electroencephalography (EEG) mask. Ten horses from the teaching herd at the University of Veterinary Medicine Vienna were observed over four consecutive nights in two different housing systems (a large communal stable vs. two separate, adjacent individual stalls). Data collection included EEG reco...
Pulsed wave tissue Doppler imaging of the left ventricle in foals: Feasibility, inter- and intra-observer variability and wave pattern over the first days of life.
Equine veterinary journal    August 4, 2026   doi: 10.1002/evj.70304
D'el Rey Dantas FT, Hallowell G, Castagnetti C, Romito G, Menchetti L, Mannini A, Lanci A, Mariella J, Freccero F.Tissue Doppler imaging (TDI) may improve the assessment of myocardial function in neonatal foals. Objective: To document the feasibility of left ventricular pulsed wave (PW) TDI, inter- and intra-observer variability and wave pattern over the first 5 days of life. Methods: Prospective observational study. Methods: Transthoracic echocardiography was performed in 25 healthy Standardbred foals within the first 24 h after birth (T1), between 60-84 h (T2), and 108-132 h (T3) after birth using right parasternal short-axis (R-LV SAX) and subcostal long-axis views at the mitral annulus, both a...
Race type and race distance as determinants of unseat events in U.S. steeplechase racing, 2023-2025.
Preventive veterinary medicine    August 4, 2026   Volume 256 106983 doi: 10.1016/j.prevetmed.2026.106983
Markowitz JS.Unseat events in steeplechase racing, including falls and lost-rider incidents, affect equine welfare and jockey safety. Timber races are often perceived as higher risk than hurdle/fence races, but are also longer. Methods: This retrospective observational study analyzed 3070 U.S. National Steeplechase Association hurdle/fence and timber starts from 2023 to 2025. Flat, steeplethon, training, and apprentice/amateur-apprentice starts were excluded. Crude rates of falls, lost-rider incidents, and combined unseat events were compared between race types. Multivariable Poisson regression examined ...
A postmortem grading system for articular cartilage loss of the dorsoproximal aspect of the proximal phalanx of Thoroughbred racehorses. Gibson MJ, Dittmer KE, Legg KA, Wehrle-Martinez AS, Beggan CP, Sommerville GO, Rogers CW.The metacarpophalangeal and metatarsophalangeal joints in Thoroughbred racehorses are common injury sites, given their high range of motion and compression during galloping. In New Zealand, the proximal phalanx (P1) is a common site for race-day fracture, but the lesions of this bone have not been described. Therefore, we created a scoring system to describe cartilage on the dorsoproximal aspect of P1 in New Zealand Thoroughbred racehorses. We collected 102 P1s from racehorses submitted for postmortem examination. Horses were categorized into 2 cohorts: 1) fracture (18 horses euthanized becaus...
Effect of neonatal rib fracture repair on racing and sales performance in Thoroughbreds.
Equine veterinary journal    July 28, 2026   doi: 10.1002/evj.70218
Young LM, Courtney ER, Freeland RB.The racing outcome of horses that have undergone surgical repair of neonatal rib fractures is not well documented. Objective: To evaluate the impact of surgical repair of neonatal rib fractures on subsequent sales and racing performance in Thoroughbreds. Methods: Retrospective cohort study. Methods: Medical records of neonatal Thoroughbreds that underwent surgical repair of rib fractures at a referral hospital between 2014 and 2025 were reviewed. Sales and racing data were obtained from publicly available databases. Outcomes assessed included sale price at weanling and yearling sales, total ca...
Differences between horses (Equus caballus) displaying oral and locomotor stereotypies in their responses to a stable mirror.
Behavioural processes    July 28, 2026   105415 doi: 10.1016/j.beproc.2026.105415
Lewis K, McBride SD, Parker MO, Faithfull R, Proops L.Recent cross-species analyses suggest that the different forms of stereotypic behaviour have heterogeneous causal mechanisms. In ungulates, there are indications that some forms of locomotor stereotypy may be linked to social factors. Using the domestic horse as a model species within this clade, we investigated whether individuals displaying the locomotor stereotypy box-walking (n=6) demonstrated greater responses to a stable mirror, intended to mimic presence of a conspecific, than horses displaying the oral stereotypy crib-biting (n=5) and non-stereotypic horses (n=5). After a 24hr baseline...
Bacteremia in horses undergoing routine dental prophylaxis: Before, during, and after the procedure.
Equine veterinary journal    July 26, 2026   doi: 10.1002/evj.70207
Dockery A, Whitfield-Cargile C, Knopp V, Sinay T.Transient bacteremia after dental procedures is well-documented in the literature, but the prevalence and clinical significance in horses remains largely unexplored. Objective: To assess whether routine dental prophylaxis in clinically healthy horses is associated with detection of bacteria in blood, using culture and 16S rDNA sequencing. Our central hypothesis is that a percentage of horses would demonstrate detectable but transient bacteremia in the immediate post-procedural period following dental prophylaxis. Methods: Prospective, observational study. Methods: Venous blood samples from 20 ...
Vasopressin stimulation testing in hospitalized foals.
Journal of veterinary internal medicine    July 23, 2026   Volume 40, Issue 4 aalag149 doi: 10.1093/jvimsj/aalag149
Albrecht M, Perez J, Wong D, Browne N, Burns T, Stevens ME, Dembek K.Hypothalamic-pituitary-adrenal gland axis (HPAA) dysfunction impairs survival and can be diagnosed with an arginine vasopressin (AVP) stimulation test. Objective: Adrenocorticotropic hormone (ACTH) and cortisol response to an AVP stimulation test will be attenuated in hospitalized foals compared to healthy foals and associated with severity of disease. Methods: Fifteen healthy and 45 hospitalized foals: 19 septic, 26 sick non-septic (SNS). Methods: A prospective, observational case-control design was utilized to assess HPAA function and compare corticotropin-releasing hormone, ACTH, and cortis...
An observational study evaluating the environmental impact of equine arthroscopy.
The Veterinary record    July 23, 2026   doi: 10.1002/vetr.70981
White K, Hillen F, Hird J, Byrne C, Shipman R, Taylor P.Human pressures on Earth's life‒support systems have exceeded multiple planetary boundaries, highlighting the need for sectors, including veterinary healthcare, to reduce environmental impacts. Methods: A prospective convenience sample of 10 horses undergoing arthroscopy at a UK equine hospital between January and March 2025 was studied. Data were collected on anaesthesia, volatile capture, pharmaceuticals, single-use consumables, waste, building energy and travel by horses and staff. Carbon emissions (kgCOe) were calculated using published conversion factors. A hybrid methodology combined b...
Growth Performance, Milk Productivity, Productive Longevity, and Milk Composition of Mugalzhar Horses.
Animals : an open access journal from MDPI    July 22, 2026   Volume 16, Issue 14 2272 doi: 10.3390/ani16142272
Toishimanov M, Alikhanov O, Aubakirov K, Karibayeva D, Kargaeva M, Sapakhova Z, Begaliyeva D, Kanat R, Tugunova Y, Daurov D, Daurova A, Zhambakin K....The Mugalzhar horse is an important native breed of Kazakhstan, valued for its adaptability, milk production, and meat productivity under extensive pasture-based management. This study evaluated the relationships among first-lactation milk yield, productive longevity, lifetime milk production, growth, morphometric traits, and milk composition in the Mugalzhar horse breed using data from 100 mares with complete lifetime production records, 108 adult mares and 12 stallions for morphometric evaluation, and 68 foals (35 colts and 33 fillies) for growth analysis. The study was conducted on Mugalzha...
Phenotypic and genetic factors that affect the likelihood of Standardbred foals achieving a race start.
Scientific reports    July 20, 2026   doi: 10.1038/s41598-026-63159-x
Tanner JC, Beatson PR, Hickford JGH, Barrell GK.This study was conducted to quantify the probability of a Standardbred foal attaining early career milestones and to estimate some environmental and genetic factors that influence achievement of those milestones. Data for all Standardbred foals registered at birth in New Zealand from 1995 to 2018 were used to estimate variance components and fixed effects influencing attainment of three early-career traits; registered with trainer (REG), starting in a trial (TRIAL) and starting in a race (RACE). The study population comprised 65,256 foals. Of these, 65.5% attained REG, 55.4% progressed to TRIA...
Differential shaping of equine gut microbiota structure and function by breed and feeding regimen.
Frontiers in microbiology    July 16, 2026   Volume 17 1852554 doi: 10.3389/fmicb.2026.1852554
Lin Y, Qiri G, Du M, Dugarjaviin M, Cao J, Fang X, Yun S, Li X, Gong W, Ding W, Bou T, Su S, Chen J, Xing N, Bai D, Zhao Y.The gut microbiota plays an essential role in host energy metabolism and immune function. Horses are non-ruminant herbivores that rely heavily on hindgut microbial fermentation to meet their energy requirements. However, the relative contributions of host genetic background (breed) and environmental factors (feeding regimen and geographical location) to shaping the equine gut microbiota remain poorly understood. Unassigned: In this study, 16S rRNA gene sequencing and functional prediction analysis were performed on 139 equine fecal samples to systematically investigate the differential effects...
Electrocardiographic recordings of foals using a new smartphone-based digital device.
Journal of equine veterinary science    July 14, 2026   Volume 166 106097 doi: 10.1016/j.jevs.2026.106097
Tognetti E, Mannini A, Freccero F, Bindi F, Cingottini D, Mariella J, Marmorini P, Sgorbini M.Smartphone-based electrocardiography (ECG) is increasingly explored as a practical tool for cardiac assessment in veterinary species. Objective: The aim of this prospective observational study was to investigate the usability and reliability of a new smartphone-based ECG system (Eko DUO) in healthy foals. Methods: A total of 39 foals, aged 1 to 59 days, were enrolled. ECGs were recorded using the smartphone device in all animals, while a subgroup of 10 foals also underwent simultaneous recording with a conventional base-apex ECG (rECG) to enable direct comparison. All tracings were reviewed bl...
Comparison of Rectal and Intraoperative Findings in Horses with Colic.
Animals : an open access journal from MDPI    July 13, 2026   Volume 16, Issue 14 2175 doi: 10.3390/ani16142175
Schlote MT, Merle R, McCullagh S, Obrochta B, Hennessy S, Dosi M, Gehlen H.Per rectum examination (PRE) is commonly used in the triage of horses with acute abdominal pain, despite reports of associated risk factors for both horses and personnel, but its diagnostic accuracy is questionable. This multicenter, observational study aimed to evaluate the agreement between PRE findings and surgical findings obtained via exploratory laparotomy in horses with colic. A total of 201 cases from four equine referral hospitals across Europe were included. Rectal findings were categorized as primary (most likely cause of colic) or additional. Agreement with surgical findings was as...
Activity type, sex, season, and number of prior starts are associated with proximal sesamoid bone fractures in Thoroughbred racehorses in South Korea.
Journal of the American Veterinary Medical Association    July 8, 2026   1-8 doi: 10.2460/javma.26.04.0244
Choi Y, Parkin TD.To identify risk factors associated with proximal sesamoid bone fractures in Thoroughbreds in South Korea. Unassigned: A retrospective case-control design with multivariable logistic regression was used. This study included 138 Thoroughbreds diagnosed with proximal sesamoid bone fractures following racetrack activity between 2020 and 2025. Additionally, 580 healthy Thoroughbreds (635 observations) with at least 1 racetrack activity during the same period were included as controls. Unassigned: A total of 7 risk factors were identified. Races or trials had markedly higher fracture risk than race...
Influence of collection site on cerebrospinal fluid test results in horses with equine protozoal myeloencephalitis.
Journal of veterinary internal medicine    July 8, 2026   Volume 40, Issue 4 aalag135 doi: 10.1093/jvimsj/aalag135
Furr MO.Cerebrospinal fluid (CSF) analysis is a critical component in the diagnosis of equine protozoal myeloencephalitis (EPM). Test results obtained may differ based on different collection sites. Objective: Compare results of EPM-specific diagnostic tests obtained from different collections sites in EPM-affected and non-EPM affected horses. Methods: Twenty control and 7 EPM-affected horses. Methods: Prospective observational study. CSF was collected from the lumbosacral (LS) and cranial sites (atlantooccipital or C1-2) in 27 horses and EPM-specific diagnostic tests were performed. Data were summari...
Validation of an improved insect bite hypersensitivity severity score for allergic equine insect bite hypersensitivity in horses.
Journal of veterinary internal medicine    July 7, 2026   Volume 40, Issue 4 aalag132 doi: 10.1093/jvimsj/aalag132
Lam J, Eckert A, Rhiner T, Waldern N, Schwarz E, Birkmann K, Widmer D, Dietrich M, Kündig TM, Fettelschoss-Gabriel A.Insect bite hypersensitivity (IBH) is the most common allergic skin disease in horses, but existing clinical scoring systems lack extensive validation, limiting standardized disease monitoring and therapeutic evaluation. Objective: Develop and validate a standardized, sensitive, and reproducible clinical scoring system for IBH in horses. Methods: Forty-four privately-owned horses with clinically diagnosed IBH examined under field conditions in Switzerland. Methods: In this prospective field validation study, the equine IBH severity score (EqIS) integrates a lesion severity score and an area sc...
Behaviour and Movement Activity of Stallions and Geldings in Group Housing.
Veterinary sciences    July 7, 2026   Volume 13, Issue 7 660 doi: 10.3390/vetsci13070660
Apitzsch RC, Handel S, Krueger K.There has been little research on the social behaviour of stallions and geldings kept together in group housing systems. The aim of this study was to investigate differences in behaviour and movement activity between stallions and geldings kept together in group housing. Behavioural observations and GPS measurements were conducted in Germany from July to September 2024 in four mixed groups of horses in Germany. The groups comprised 35 animals, 18 stallions and 17 geldings. The horses were observed for three consecutive days over eight hours per day. No injuries or stereotypic behaviours were o...
Prevalence and radiographic features of cyst-like lesions in German Warmblood horses presented for pre-purchase examination.
Frontiers in veterinary science    July 6, 2026   Volume 13 1809383 doi: 10.3389/fvets.2026.1809383
Wendling EM, Hellige M, Freise F, Lingens P, Tietje S, Delling U.Cyst-like lesions (CLLs) are frequently detected during radiographic examinations of equine limbs. They may represent a potential risk factor during pre-purchase examination (PPE) and are of considerable clinical and economic importance, as they may lead to negative purchase decisions. While affected horses may develop lameness, incidental findings have also been reported. The goal of the study was to describe the prevalence, location and radiographic characteristics of CLLs in a group of sound German Warmblood horses. Unassigned: A retrospective cohort study was conducted on 3863 German Warmb...
Determining optimal practices for foal weaning – A protocol for a systematic review and network meta-analysis.
PloS one    July 1, 2026   Volume 21, Issue 7 e0352182 doi: 10.1371/journal.pone.0352182
Cranston N, Buckley P, Rose L, Loy J, Randle H.Weaning is a stressful time in a foal's (Equus caballus) life. As humans artificially manage weaning in domestic horses, it provides an opportunity to safeguard horse welfare early in life, with potential long-term benefits. While numerous studies have examined the effects of different weaning and management interventions on foal stress, optimal weaning practices have yet to be identified. Overall purpose of the study: To identify which weaning interventions and management practices have the greatest potential to improve foal welfare based on physiological and behavioural outcomes. Research qu...
Risk factors for post-partum colic in a population of UK and Irish Thoroughbred broodmares.
Equine veterinary journal    June 30, 2026   doi: 10.1002/evj.70219
Cullen E, Carslake HB, Henderson I, Stoneham S, Pinchbeck GL, Archer DC.Broodmares are at increased risk of gastrointestinal colic. However, colic risk factors specific to this population have not been investigated. Objective: To investigate horse- and management-level risk factors for post-partum colic in a cohort of Thoroughbred broodmares in the United Kingdom and Ireland. Methods: Prospective, nested case-control study. Methods: Twenty-nine Thoroughbred stud farms in the United Kingdom and Ireland were recruited, and 1044 mares were followed over the 2021 and/or 2022 foaling seasons. Data were collected on signalment, medical and management history for post-pa...
Inertial measurement units are comparable to motion capture for measuring intersegmental spinal angular velocities in horses.
American journal of veterinary research    June 29, 2026   1-7 doi: 10.2460/ajvr.26.04.0149
Ursini T, Clayton H, Levine D, Richards J.To compare inertial measurement unit (IMU)-derived intersegmental spinal motion data with measurements obtained from a marker-based motion-capture system. Unassigned: 4 horses were instrumented with custom marker clusters incorporating a 3-D-printed base designed to secure the IMU, ensuring both systems recorded data from the same anatomical location and orientation. A total of 3,737 paired time points across 37 gait cycles were analyzed. Agreement in intersegmental angular velocities across 3 planes of motion was evaluated using Bland-Altman analysis and intraclass correlation coefficients. U...
Fatalities within seven days after equine standing sedation: A prospective, multicentre study.
Equine veterinary journal    June 25, 2026   doi: 10.1002/evj.70183
Gozalo-Marcilla M, Redondo JI, Taylor PM, Domenech L, Doménech J, Johnston GM, Bettschart-Wolfensberger R.Information regarding mortality associated with standing procedures in horses is sparse. Objective: To report data from >12,000 standing sedations. Methods: Confidential, observational, prospective, multicentre, cohort study. Methods: We collected records of horses/ponies undergoing standing sedation for surgery or advanced diagnostic imaging using at least one top-up or controlled rate infusion (CRI). Procedures were either NON-COLIC or COLIC. Outcome at seven days was recorded as (i) ALIVE, (ii) EUTHANASIA or (iii) DEAD. Data were collected with a portable document format (PDF) questionn...
Effect of exercise-related nasopharyngeal disorders on upper airway function in racehorses.
Equine veterinary journal    June 24, 2026   doi: 10.1002/evj.70211
Vermedal H, Hellings IR, Fretheim-Kelly ZL, Fintl C, Strand E.Exercise-related upper respiratory tract (URT) disorders are frequently diagnosed in racehorses. Treatment recommendations are routinely based on subjective assessment of clinical evaluation and exercising endoscopy findings. Objective: To objectively investigate how palatal instability (PI), intermittent dorsal displacement of the soft palate (iDDSP), alar fold collapse (AFC), and nasopharyngeal collapse (NPC) affect upper airway function during exercise in racehorses. Methods: Observational study with case-control comparisons. Methods: Inspiratory and expiratory tracheal pressures (cmHO) wer...
Interpreting the CEPEF4 data: Handling small data subsets without losing confidentiality.
Equine veterinary journal    June 24, 2026   doi: 10.1002/evj.70220
Taylor PM, Gozallo-Marcilla M, Johnston GM, Bettschart-Wolfensberger R, Redondo JI.No abstract available
Advanced paternal age is associated with reduced reproductive success and offspring racing performance in Australian Thoroughbred racehorses.
Scientific reports    June 23, 2026   doi: 10.1038/s41598-026-59342-9
Jenkins C, Upton R, Griffin RA, Swegen A, Hamilton NA, Gibb Z.Reproductive ageing influences fertility and offspring fitness across mammals. In humans and model organisms, paternal age has been associated with changes in sperm quality and genomic integrity, including oxidative stress, DNA damage, and epigenetic alterations; however, these mechanisms have not been directly examined in large equine populations. Thoroughbred racehorses provide a system to investigate paternal age effects at scale using detailed breeding records. In this retrospective observational study, with data from 35 retired stallions and 33,546 progeny, we assessed associations betwee...
Phenotypic characterization through identification of gait and coat color phenotype of the Mountain Pleasure Horse.
Journal of equine veterinary science    June 17, 2026   106066 doi: 10.1016/j.jevs.2026.106066
Irons A, Culwell J, Nicodemus MC, Vandiver M, North E, Cavinder C, Rios de Alvarez L, Williams T.Phenotypic characterization of traits like gait and coat color is useful for minor breed identification and conservation. The Mountain Pleasure Horse (MPH) is a minor American breed as it is listed as threatened by the Livestock Conservancy. Objective: The study objective was to utilize phenotypic characterization for identifying gait and coat color phenotype of the MPH. Methods: Gait was characterized utilizing frame-by-frame analysis to identify spatiotemporal variables of purebred horses (n = 6) performing the flat walk and saddle rack. Coat color was characterized using coat color assi...
Mastication characterization of horses fed bermudagrass hay in a two-part field study.
Journal of equine veterinary science    June 17, 2026   106068 doi: 10.1016/j.jevs.2026.106068
Long JF, Hutton R, Abrams A, Duberstein JA, Duberstein KJ.Bermudagrass (Cynodon dactylon L.) is a common forage in the southeastern United States but remains controversial in equine diets due to reported associations with impaction colic. Reduced fiber digestibility has been proposed as a contributing factor, however differences in mastication of fine-stemmed bermudagrass hay have not been studied and may play a role in digestive disturbances. Objective: To compare chewing characteristics, including chews per unit weight and chews per minute, in horses consuming bermudagrass hay compared to other common hay types. Methods: Two studies were conducted....
Rider dislodgement events in U.S. steeplechase racing: participation outcomes in riders and horses.
Injury epidemiology    June 15, 2026   doi: 10.1186/s40621-026-00696-z
Markowitz JS.Steeplechase jockeys compete in high-risk races requiring horses and riders to clear fixed obstacles at speed. Although rider dislodgement events are recognized hazards, their incidence and participation consequences are not well characterized. Methods: This retrospective observational study used publicly available race charts from United States National Steeplechase Association races (2023-2025). Dislodgement events were defined as falls or lost rider events. Incidence rates were calculated per 1,000 starts, and timber and hurdle races were compared using Poisson regression. Rider interruptio...