Experimental methods in equine research encompass a variety of techniques and procedures used to investigate physiological, behavioral, and health-related aspects of horses. These methods are designed to collect data that can enhance the understanding of equine biology and inform veterinary practices. Common experimental approaches include controlled trials, observational studies, and laboratory-based experiments. Techniques may involve the use of non-invasive imaging, biochemical assays, and physiological monitoring to assess parameters such as metabolic function, locomotion, and disease progression. This page compiles peer-reviewed research studies and scholarly articles that explore the application, development, and evaluation of experimental methods in the study of equine science.
Science (New York, N.Y.)July 19, 1946
Volume 104, Issue 2690 53-54 doi: 10.1126/science.104.2690.53
Sulkin SE, Goth A, Zarafonetis C.Anesthesia, by ether, is effective in the treatment of western equine encephalomyelitis in mice. Of mice treated with deep ether anesthesia soon after the intracerebral injection of western equine virus, only 58 per cent developed the disease as compared with 92.4 per cent of control animals. When anesthesia was delayed the approximate length of the incubation period, 60 per cent of the animals developed the disease as compared with 92.4 per cent of the controls. In addition, ether anesthesia delays the development of central nervous system symptoms not only when administered soon after the in...
Bang FB.The titration curve for the virus of Eastern equine encephalomyelitis inoculated into the 10 day old chick embryo shows that the maximum increase in virus content continues until shortly before the generalized destruction of the embryo is apparent. This is followed by a stationary phase. Histological studies of infected embryos fail to demonstrate selective tissue destruction, and titrations show the virus to be distributed throughout the egg, although concentrated in the embryo. The chorioallantoic membrane gradually becomes increasingly resistant with age to both the Eastern and Western viru...
King LS.The behavior of a fixed strain of Eastern equine encephalomyelitis virus was studied in guinea pigs after intraocular inoculation. Such inoculation concerns the central and not the peripheral nervous system. The susceptibility to intraocular injection lies midway between the highly virulent intracerebral and the quite avirulent peripheral routes. The virus must act for 10 to 13 hours in order to induce a fatal infection. Removal of the inoculated eyeball before this interval almost always prevents fatality although it may allow immunity to develop. The virus, at suitable intervals after inject...
Smith T.The foregoing and earlier data taken together demonstrate that an active immunity lasting several years can be produced in guinea-pigs, by the injection of toxin-antitoxin mixtures which have no recognizable harmful effect either immediate or remote. They also show, what might have been anticipated, that under the same conditions mixtures which produce local lesions and which, therefore, contain an excess of toxin produce a much higher degree of immunity than the neutral mixtures, and that an excess of antitoxin reduces the possibility of producing an active immunity, and may extinguish it alt...
To document morphologic changes that occur in equine intestinal serosa after experimentally induced ischemia and subsequent reperfusion (jejunum, ascending colon) or after intraluminal distention and decompression (jejunum). Methods: Morphologic effects of ischemia-reperfusion or intraluminal distention-decompression determined on the serosal layer of the equine jejunum. The large colon serosa was evaluated after ischemia-reperfusion injury. Methods: Seven adult horses. Methods: After induction of general anesthesia and ventral median celiotomy, ischemia was created by arteriovenous (AVO) and ...
In horses, osteoarthritis (OA) mostly affects metacarpophalangeal and metatarsophalangeal (fetlock) joints. The current modalities used for diagnosis of equine limb disorders lack ability to detect early OA. Here, we propose a new alternative approach to assess experimental cartilage damage in fetlock joint using Acoustic Emissions (AE). Objective: To evaluate the potential of AE technique in diagnosing OA and see how AE signals changes with increasing severity of OA. Methods: An in vitro experimental study. Methods: A total of 16 distal limbs (8 forelimbs and 8 hindlimbs) from six Finn horses...
Muñoz-García CC, Soriano-Campos MP, Luis-Calero M, Gallardo-Soler A, González-Fernández L, Macías-García B.The use of mesenchymal stromal cells (MSCs) in equine reproduction is increasing its interest in the treatment of specific pathologies. MSCs have been isolated from follicular aspirates obtained during transvaginal oocyte aspiration in women, offering a novel source for autologous therapies in reproductive treatments. However, this approach has not been tested in mares despite the common use of transvaginal oocyte aspiration for oocyte collection to produce equine embryos in vitro. Our study aimed to investigate the feasibility of isolating MSCs from equine ovarian follicular aspirates obtaine...
Delcourt V, Pinetre J, Chabot B, Barnabé A, Cacault M, Loup B, Becher F, Fenaille F, Popot MA, Garcia P, Bailly-Chouriberry L.Data-independent acquisition (DIA) methods employing a scanning quadrupole were recently described across multiple platforms. These strategies display remarkable performances in untargeted proteomics studies thanks to rapid duty cycles, leading to ultrashort liquid chromatography gradients while maintaining enough data points per peaks when coupled to fast-scanning mass analyzer. In this article, we perform the evaluation of three data acquisition strategies named diaPASEF,slicePASEF, and prmPASEF on a trapped ion mobility spectrometry quadrupole-time-of-flight (TIMS-Q-TOF) mass spectrometer f...
Khorsand F, Hamali H, Qasemi-Panahi B, Tohidkia M.This study evaluated the effects of supplementation of the freezing extender with different concentrations of silymarin on the quality of frozen-thawed Arabian stallion spermatozoa. Semen samples from three stallions (1, 2, and 3) were suspended in the freezing extender without or with silymarin (0, 25 μg/mL, 50 μg/mL, 75 μg/mL, and 100 μg/mL) and cryopreserved in 0.5 mL straws. After 1 month of storage, the frozen semen samples in straws were thawed and evaluated in terms of viability, mitochondrial membrane potential, kinematic parameters, total and progressive motility, plasma membrane ...
Lefèvre RA, Barluet de Beauchesne L, Sabarros F, Briefer Freymond S, Ramseyer A, Keller M, Reby D, Fitch WT, Briefer ÉF.Understanding why the frequencies of some species' vocalizations are far above or below those predicted by body size is key for explaining the remarkable diversity of mammalian vocal behavior. Horses, among the largest terrestrial mammals, provide a clear example of such deviation: their whinnies contain a very high fundamental frequency (>1,000 Hz) in addition to a second, lower one (∼200 Hz). While the lower fundamental frequency of whinnies is readily attributed to vocal fold (laryngeal) vibrations, the biomechanical processes underlying the production of the higher one remain unknown. Us...
Helmer A, Hacohen A, Bart O.Equine-Assisted Services (EAS) encompass a range of therapeutic interventions utilizing equine interactions to achieve therapeutic goals. This study explores heart rate synchronization between horses and riders during mounted and unmounted interactions, focusing on its potential implications for emotional regulation. A total of 25 participants aged 6-12 took part in the study, which included two groups: novice riders diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) (n = 15) and experienced neurotypical riders (n = 10). Heart rate measurements were obtained using Polar Equ...
Dlugopolska D, Siwinska N, Noszczyk-Nowak A.Asthma is a multifactorial respiratory disease that naturally occurs in horses, humans, and cats, presenting common clinical signs and species-specific mechanisms. This review addresses the impact of asthma on the cardiovascular and neurological systems, with a primary focus on horses. It highlights the need for new biomarkers beyond the respiratory system due to diagnostic difficulties in animals. A comprehensive literature search was conducted using PubMed and Google Scholar, focusing on cardiovascular and neurological manifestations of asthma in humans, horses, cats, and experimental animal...
Lanning BA, Smith CM, Ugale C, Nazarenko E, Marchand WR.Equine-assisted services (EAS) are used for civilian and military trauma survivors to reduce depression and posttraumatic stress symptoms. While early scientific evidence supports the benefits of EAS, the neurophysiological mechanisms underlying these benefits are unknown. The specific aims of this exploratory study were to determine (1) whether functional near-infrared spectroscopy (fNIRS) neuroimaging can be used to explore neural responses of EAS veteran participants and (2) the correlation between neural responses and psychological outcomes of the participants interacting with equines. Fif...
Hu B, Gao S, Zhang H, Li Q, Li G, Zhang S, Xing Y, Huang Y, Han S, Tian Y, Zhang W, He H.Rhodococcus equi (R. equi) is a Gram-positive zoonotic pathogen that frequently leads to illness and death in young horses (foals). This study presents the complete genome sequence of R. equi strain BJ13, which was isolated from a thoroughbred racehorse breeding farm in Beijing, China. Results: The BJ13 genome has a length of 5.30 Mb and consists of a complete chromosome and a plasmid measuring 5.22 Mb and 0.08 Mb, respectively. We predicted 4,929 coding gene open reading frames, along with 52 tRNAs and 12 rRNAs. Through analysis of mobile genetic elements, we identified 6 gene islands and ...
Smith CM, Weimann K, Widick M, Merritt T, Christensen H, Siegel M, Pan Z, Gabriels RL.The purpose of this paper is to serve as a catalyst for the human-animal interaction research field to improve scientific rigor and accelerate the knowledge of field-based physiological responses during equine-assisted services in youth with autism spectrum disorder. This paper outlines the best practices for collecting and analyzing electrocardiogram and electrodermal activity in youth with autism spectrum disorder, utilized during a 10-week therapeutic horseback riding intervention.•Motivation strategies such as device choice, reward systems, and a visual schedule should be implemented to ...
Daniels S, Martin S, Harris P, Moore-Colyer M.The in vitro gas production system (GPS), developed to estimate degradation of ruminant feedstuffs, has been adapted for equine use. This study aimed to characterise the bacterial community profile and metabolome of donor faeces and faecal inoculum within the GPS when fermenting the same diet as faecal donors. Six Welsh ponies on identical diets were faecal donors with samples collected for microbiome profiling and system inoculation. Gas production (manual pressure transducer technique) was performed for 156 h with 2 replicate bottles from each donor harvested at 8,20,28 and 36 h. Faecal an...
Journal of biomechanicsJanuary 16, 2026
Volume 197 113169 doi: 10.1016/j.jbiomech.2026.113169
Collins AE, Wayne JS, Ferrando CA, De Vita R.This experimental study characterizes the elastic behavior of male and female equine genital tissues using uniaxial tensile testing, with strain measurements obtained via digital image correlation. Dog-bone-shaped tissue specimens were excised from mares and geldings (n=23 from female specimens and n=42 from male specimens) with all specimens aligned along the circumferential direction (CD) of the vagina, penis, and scrotum. The results include load-displacement data, stress-strain data, and tangent moduli for the penile sheath, vaginal canal, and scrotum, with strain measured in both the CD a...
Van Buren SL, Petersen JL, Brown CT, Finno CJ.With advancing genomic technologies, single-nucleotide polymorphism (SNP) arrays and whole genome sequencing (WGS) have become essential tools in equine genetic research. In this study, we assessed the concordance in SNP calls and trait-mapping efficacy by comparing data of 21 horses both genotyped on the Equine 670 K SNP array and sequenced at either ~12× or ~30× depth. Our analysis revealed that higher sequencing depths were significantly associated with fewer discordant calls between platforms. Additionally, we investigated the most frequent no-call and discordant positions and identifi...
Naber A, Kreuzer L, Zink R, Millesi E, Palme R, Hediger K, Glenk LM.This exploratory study aimed to analyse physiological interaction processes in equine-assisted-therapy (EAT) between client, therapy horse and therapist. Methods: We measured heart rate (HR), heart rate variability (HRV) and cortisol levels before, during and after a standardized therapy session and a control condition in one therapist, four therapy horses and ten female clients in emerging adulthood (Mn = 21.8 years, SD = 3.39). The clients were diagnosed with mild (N = 5) to moderate (N = 5) intellectual disability (ID). Results: There was no significant change in the client's HR, HR...
Suganuma K, Fujita G, Macalanda AMC, Regilme MAF, Izumida H, Inoue N, Acosta TJ.Horseflies are pests that cause discomfort from blood-sucking and disease transmission, and economic losses in the equine industry. This study evaluated the efficacy of horsecloth impregnated with icaridin in reducing horsefly attacks and deterring horseflies. Repellent activities were evaluated under three conditions: treatment 1 (no horsecloth), 2 (horsecloth without icaridin), and 3 (horsecloth impregnated with icaridin), using three native Hokkaido horses (Dosanko) and three mixed-breed horses (Dosanko and Haflinger) in July 2023 at a riding horse club in Hokkaido, Japan. Treatment 3 signi...
Gaitan HM, Mudge MC, Litsky AS, Arruda AG, Gardner AK.To compare strength of left paramedian colopexies using various techniques in equine ex vivo models. Methods: Experimental study. Methods: Equine cadavers euthanized for nongastrointestinal pathology (36 specimens derived from 9 horses). Methods: Colopexies were performed after euthanasia. Suture pattern (horizontal mattress vs. cruciate) and incorporation of dorsal sheath of the rectus abdominis (partial-thickness) versus incorporation of dorsal and ventral sheath of the rectus abdominis (full-thickness) were evaluated. Single cycle load to failure, work to peak load, stiffness, and mode of f...
Douglas HF, Brandly J, Hopster K.To investigate the effects of FLow-controlled EXpiration (FLEX) ventilation expiration time and speed on respiratory and pulmonary mechanics in anesthetized horses in dorsal recumbency. Methods: 6 healthy adult research horses. Methods: In this randomized crossover experimental study, horses were anesthetized 3 times and were ventilated each time for 60 minutes using conventional volume-controlled ventilation (VCV), linear emptying of the lung over 50% of the expiratory time (FLEX50), or linear emptying of the lung over 100% of the expiratory time (FLEX100) in a randomized order. The primary o...
Guyonnet AE, Whishaw IQ.The domestic horse (Equus ferus caballus) makes dung deposits to form "stud-piles" and compulsively examines dung droppings, suggesting that dung contains species-relevant information. The present study investigates horses' use of location (place), odor (object) and memory for dung sniff encounters. Horses were video recorded in 2 indoor and 4 outdoor riding arenas as they were taken at different time intervals to experimenter-determined objects or dung deposits that they could sniff. Frame-by-frame video analysis measured approaches, sniff duration, nostril use, ear position and blinking asso...
Fournier AK, French M, Letson EA, Hanson J, Berry TD, Cronin S.This study examined human-animal symbiosis in an animal-assisted intervention through observations of animal maintenance behaviors. The rise of psychotherapy, learning, and recreation incorporating animals warrants exploration of the welfare of the animals involved in these interventions. The analysis of welfare in multispecies engagements can be discussed in terms of symbiosis. Regarding an intervention's animal provider (e.g., therapy horse) and human recipient (psychotherapy client), the balance of cost and benefit is important. Research describing human and animal during interventions is ...
Hennig VE, Luís da Silva A, Zanetti MS, Copetti F.Hippotherapy uses horseback riding movements for therapeutic purposes. In addition to the horse's movement, the choice of equipment and types of positions are also useful in the intervention. Trunk postural control demands can be manipulated through varying mounting materials and patient positioning on the horse. The quantification of trunk dynamic parameters under the interaction of the different types of riding material and the position variations act upon trunk postural control provides insight into how children with neurotypical development respond to a similar hippotherapy session. This s...
Brooks L, Ryan M, McCosham E, Loganathan D.In 2009, levamisole was identified as a source for several aminorex positives reported in postrace equine samples in Canada. Since then, unexplained detections of aminorex continue to be identified in equine samples where there is no evidence to link these detections to a levamisole administration. Previous studies identified a compound named barbarin in some species of plants from the Brassicaceae family and suggested that barbarin may be a possible precursor for aminorex. The objectives of this study were to (1) investigate the link between barbarin and aminorex and (2) identify other biomar...
Chen J, Yablon A, Metaxas C, Guedin M, Hu J, Conover K, Simpson M, Ralston SL, Krishnamurthy K, Pelczer I.: There are a few very specific inflammation biomarkers in blood, namely lipoprotein NMe signals of protein clusters (GlycA and GlycB) and a composite resonance of phospholipids (SPC). The relative integrals of these resonances provide clear indication of the unique metabolic changes associated with disease, specifically inflammatory conditions, often related to serious diseases such as cancer or COVID-19 infection. Relatively complicated, yet very efficient experimental methods have been introduced recently (DIRE, JEDI) to suppress the rest of the spectrum, thus allowing measurement of these ...
Patterson HE, Yocom AF, Seabaugh KA, Kawcak CE, Contino EK.Recent evidence has shown that perineural analgesia may be less specific than previously thought. Objective: To compare the effects of four distal limb perineural analgesia techniques on resolving synovitis-induced lameness of the equine metacarpophalangeal joint (MCPJ). Methods: Nine horses had one MCPJ injected with 75ng of recombinant equine interleukin-1β (reIL-1β). Ten hours later, horses underwent one of two blocking patterns: (1) a palmar digital (PDNB) followed by an abaxial sesamoidean (ASNB) nerve block or (2) a palmar metacarpal (PMNB) followed by a palmar (PaNB) nerve block. Skin...
Vargas-Pérez MÁ, Laseca N, Demyda-Peyrás S, Valera M, Ziadi C, Arjona-Delgado MY, Molina A.Long non-coding RNAs (lncRNAs) are transcripts constituted of more than 200 nucleotides that have been associated with the regulation of different biological processes by modulating the expression of key genes. In horses, evidence suggests that lncRNAs play a role in female reproductive fitness, yet their functional implications remain poorly characterized. The objective of this study was to investigate potential DNA:RNA triplex interactions between the promoter regions of fertility-related genes and lncRNAs transcribed from non-coding loci located within ±50 kb of these genes. By doing so, w...
Liu L, Cao H, Ma H, Chen B, Liu W.H3K4me3, a well-established histone modification associated with active promoters, plays a critical role in orchestrating gene expression programs that govern mammary gland development and lactation. In this study, we present the first comprehensive epigenomic profiling of H3K4me3 modifications during mammary gland development in Yili horses using Cleavage Under Targets and Tagmentation (CUT&Tag) and RNA sequencing. Mammary gland tissues were collected from two developmental stages-early lactation and peak lactation. A total of 393 differentially expressed genes (DEGs) were identified betw...
Huguet A-S, Gourbeyre O, Bousquet-Mélou A, Ferran AA, Lallemand EA. is an opportunistic intracellular pathogen responsible for severe respiratory infections in foals, requiring prolonged antibiotic treatment. Despite its susceptibility to multiple antibiotics, the eradication of intracellular remains challenging due to its ability to persist and survive within alveolar macrophages. This study aimed to assess the extracellular and intracellular activity of rifampicin, doxycycline, and four macrolides against while assessing current methodologies used to differentiate intracellular and extracellular bacteria. We found that the removal of extracellular wit...
Furukawa R, Tozaki T, Kawate K, Kikuchi M, Ishige T, Fukui E, Kakoi H.A subset of single-nucleotide polymorphisms (SNPs) are associated with various phenotypes, including diseases, coat colour, and athletic performance, and are widely used in medical and veterinary fields. In this study, we developed a novel method for direct SNP genotyping from whole blood without DNA extraction. Thoroughbred blood samples were diluted 100-fold with Milli-Q water and analysed using real-time polymerase chain reaction (PCR) with hydrolysis probes. Specificity and sensitivity were improved by increasing the annealing temperature and number of PCR cycles. Genotyping results for SN...
Öztürk Z, Tozoğlu EÖ, Eymır M, Karakurt N, Ulusoy S.To examine the effectiveness of equine-assisted therapy on symptoms, quality of life, anxiety, and loneliness in individuals with schizophrenia. Unassigned: A randomized controlled trial was conducted with individuals with schizophrenia registered at a community mental health center. The study involved 61 participants (30 in the intervention group, 31 in the control group). An 8-week equine-assisted therapeutic intervention was implemented for the intervention group. Data were collected using a Personal Information Form, the Positive and Negative Syndrome Scale (PANSS), Trait Anxiety Inventory...
Federico F, Amie W, Alzbeta C, Anders J, David LP, Mandy PJ.Cerebrospinal fluid (CSF) is a valuable source of biomarkers for neurological diseases, but detection of low-abundance proteins is often masked by highly abundant proteins. Enrichment strategies can enhance proteomic coverage and improve biomarker discovery, yet comparative evaluations of such methods in equine CSF are limited. Objective: This study compared the ProteoMiner Small-Capacity Enrichment Kit and the PreOmics Enrich-iST Kit for their ability to deplete high-abundance proteins and enhance detection of low-abundance proteins relevant to neuropathology. Methods: Equine CSF samples were...
Pollaris E, Hannes C, Haspeslagh M, Demey W, Teysen S, Boussauw B, Vlaminck L.Bit-related trauma is a welfare issue in equestrian sports; therefore, a proper understanding of how the bit behaves inside the mouth is of importance. The objective of this study is to investigate the influence of bit design (snaffle bits/single/double-jointed; ring/eggbutt and curb bits), size, rein tension, and rein angle on the intra-oral movement of the bit in ex vivo specimens. The lateral and posterior movement of different bits was measured on cadaver heads under different circumstances. This ex vivo model, while not fully replicating natural conditions, provided insight into potential...
Gulcelik GE, Sever E, Atalay B, Dursun E, Memisoglu I.PurposeThis study aimed to assess the acute effects of hippotherapy performed on different seating surfaces on sitting balance and walking speed in children with special needs.Materials and MethodsChildren aged 3-18 years with special needs were included. Participants were assigned to three groups: Group 1 (Saddle), Group 2 (No saddle, direct horse contact), and Group 3 (Saddle with additional texture material). Each group received a 30-min hippotherapy session in a riding arena. Sitting balance was measured with the BeCure balance system, and walking speed was assessed using the 10-meter walk...