"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
ALEXANDER F.No abstract available1. The magnitude of the rhythmic contractions of the perfused ileum varied with the supply of oxygen.
2. Isotonic sodium chloride solution was as good as Tyrode's solution for suspension of the red cells in the perfusion fluid.
3. Variation of the potassium and calcium content of the perfusion fluid had little effect on motility. Sodium ions had a specific function in maintaining motility.
4. The chloride ions in the perfusion fluid were replaced by bromide, phosphate and sulphate ions without affecting motility. Iodide ions were toxic.
5. The ileum perfused wi...
Knych HK, Blea J, Scollay M, Kass PH, McKemie DS.Ethanol, a central nervous system depressant and banned substance in horseracing, has reportedly been administered to horses prior to competition to "calm a horse's nerves." In this study, the pharmacokinetics of two metabolites of ethanol were studied to better understand the behavior of this compound in the horse and provide a scientific basis for regulation of its administration. Six horses received a single intravenous (30 mL; 1200 mg) and oral (90 mL; 3600 mg) administration of ethanol (vodka, 40% ABV) in a balanced cross-over design. Blood and urine samples were collected at vari...
Kopec EK, Stevens M, Crowe O, Wright C, Suthers J.The aim of the present study was to investigate the long-term survival and postoperative complications in horses that had undergone small intestinal resection and a modified anastomosis technique using a partially stapled, functional end-to-end anastomosis. Methods: Observational retrospective case series. Methods: A total of 25 horses underwent small intestinal resection and a partially stapled, functional end-to-end anastomosis. Methods: A modified technique to create a partially stapled, functional end-to-end anastomosis is described. The clinical case records of all horses that fulfilled t...
Cole RC, DeGraves FJ, Schumacher J, Brown J.To determine the effect of 1.5 mL 2% mepivacaine, 0.75 mL 2% mepivacaine, and a combination of 0.75 mL 2% mepivacaine with epinephrine (1:200,000 solution) administered over each palmar digital nerve (PDN) to 6 horses with naturally occurring lameness caused by digital pain. Methods: In a crossover study design, 6 horses with forefoot-related lameness were randomly assigned to 1 of 3 groups. Each group received, on different study days, a PDN block using 1.5 mL of 2% mepivacaine, 0.75 mL 2% mepivacaine, or 0.75 mL of a combination of 2% mepivacaine and epinephrine (1:200,000 solution) injected...
Barton CK, True A, Fenn M, Thampi P, Watson A, Smanik LE.The objective of this Case Report was to describe the clinical manifestation and postmortem findings of a horse evaluated for recurrent colic diagnosed with pyloric aplasia and an ectopic duodenal papilla. Methods: 13-year-old Quarter Horse gelding. Unassigned: The horse was presented to a referral center for signs of colic that were unresponsive to management on the farm. No abnormalities were noted on rectal palpation; however, upon passage of a nasogastric tube, 31 L of net gastric reflux was obtained. Gastroscopy noted grade IV squamous ulceration and moderate glandular ulceration, severe ...
Monteiro LC, Costa CM, Ermita PAN, Júnior SJPG, Mattos FS, Mansur FC, Dos Santos MO, Alves SR, Mafort EG, Fidélis CF, Avanza MFB, Teixeira RBC....In adult horses, the development and evaluation of enteral electrolyte solutions containing sodium acetate for correcting hyperchloremic metabolic acidosis are still lacking, although these electrolyte and acid-base imbalances are commonly observed. The objective of this study was to evaluate the alkalinizing effect of two enteral electrolyte solutions containing different concentrations of acetate, administered via nasogastric tube in continuous flow, in adult horses with experimental hyperchloremic metabolic acidosis. Unassigned: Six mares aged between 3 and 10 years were used in a 6×2 cr...
Cheung HW, Wong KS, Tam JCL, Farrington AF, Bond AJ, Wan TSM, Ho ENM.Erythropoiesis-stimulating agents (ESAs) continue to be a significant threat to the integrity of human and equine sports. Besides conventional direct testing, monitoring the biomarkers associated with the effects of ESAs may provide a complementary approach via indirect detection to enhance doping control. In this study, we applied label-free proteomics to discover plasma protein biomarkers in Thoroughbred geldings after administration with a long-acting form of recombinant human erythropoietin (rhEPO), methoxy polyethylene glycol epoetin beta, Mircera. Increased haematocrit, haemoglobin and r...
Martínez-Aranzales JR, Córdoba-Agudelo M, Pérez-Jaramillo JE.Crib-biting is a stereotyped oral behavior with poorly understood etiology and pathophysiology. The relationship between the gut microbiome and brain function has been described in behavioral disorders such as schizophrenia, depression and anxiety in humans. In horses, studies of behavioral problems and the microbiome are very limited. This study aimed to characterize the fecal microbiome and the predicted functional profile of horses with and without aerophagia. Fecal samples were collected from 12 Colombian Creole Horses of both sexes, divided into two groups: group 1, composed of six horses...
Caivano D, Cicogna M, Orvieto S, Spitale D, Porciello F.A 16-year-old horse, 400 kg, male, Quarter horse gelding was examined for a cardiac murmur that had not been previously heard. Physical examination revealed a regularly irregular pulse and a grade III/VI, decrescendo, diastolic murmur with a point of maximum intensity over the left heart base. Base-apex standard electrocardiographic examination at rest showed sinus rhythm with second-degree atrio-ventricular blocks. Echocardiography identified the presence of four aortic valve cusps, two equal larger and two unequal smaller cusps. Color flow Doppler examination showed a diastolic regurgitant j...
Vaughn SA, Berghaus LJ, Hart KA.Breed differences exist between horses and ponies in circulating concentrations of several hormones, notably ACTH and insulin. These hormones regulate stress and metabolic responses, but in other species, they also impact leukocyte oxidant responses. The effects of these hormones on equine leukocytes have not been evaluated to date. If equine leukocytes are similarly regulated, breed differences in increased plasma hormone concentrations or altered sensitivity to them at the leukocyte level could result in breed-related differences in oxidant responses or oxidative status. The objective of thi...
García Sánchez A, Zurita SG, Gil Molino M, Martin Cano FE, Barraso Gil C, Hermoso de Mendoza Salcedo J.The aim of this study is to describe an outbreak of dermatophilosis at an equestrian center in Castilla la Mancha (central Spain), which affected 16.6% (5/30) of the animals. Research was carried out to establish the mode of transmission and spread to other horses in the herd. Clinical features, diagnostic methods and treatment are also described. O objetivo deste estudo é descrever um surto de dermatofilose em um centro equestre em Castilla la Mancha (centro da Espanha), no qual 16,6% (5/30) dos animais foram afetados. Foi realizada uma pesquisa para estabelecer o modo de transmissão e a di...
Cassiers V, McNally T.Palatal dysfunction (PD), which encompasses palatal instability (PI) and intermittent dorsal displacement of the soft palate, is the most common performance-limiting upper respiratory tract obstruction in young Thoroughbred racehorses. Soft palate thermocautery (SPT) performed under general anaesthesia is a routinely performed procedure for PD in some countries, but the procedure for and outcome of SPT performed under standing sedation has not been published. (1) To describe a technique for SPT performed under standing sedation; and (2) to assess post-operative performance in horses compared t...
Faghihi H, Gharibi A, Ansari Mood M, Rajaei SM, Alavi SM.The aim of this study was to detect and describe ocular abnormalities in a population of Turkmen horses. Methods: A total of 55 Turkmen horses (33 mares and 22 stallions) from one herd were evaluated in this study. Methods: Demographic data (Age, Sex, Coat color) were recorded. All animals underwent complete ophthalmic examination. The Schirmer tear test -I (STT-I) was performed for all horses prior to other diagnostic tests. Neuro-ophthalmic examinations (menace response, dazzle reflex, pupillary light reflex, maze test, and visual tracking) were carried out in different lighting situations (...
Cornell TR, Fye BL, Nyassi E, Ceesay F, Jallow M, Langendonk RF, Wootton DG, Pinchbeck G, Scantlebury CE.Exposure rates to species, the causative agent of equine epizootic lymphangitis (EL), are unknown amongst working equids in The Gambia. The primary aims of this study were to estimate anti- antibody seroprevalence in the equid population in rural The Gambia and to explore risk factors for seropositivity. Unassigned: A nationwide cross-sectional study was conducted (February-July 2022), representing baseline measurements of a longitudinal cohort study. Horses ( 463) and donkeys ( = 92) without EL signs were recruited in 18 study sites. Following informed owner consent, equid clinical and m...
Takahashi Y, Niwa H, Ebisuda Y, Mukai K, Yoshida T, Raidal S, Padalino B, Ohmura H.Protection of horse welfare during transport is crucial. The aim of this study was to determine the effect of head and neck restraint on behavior and airway bacteria. Unassigned: In a randomized crossover study, six healthy Thoroughbreds were transported by road for 22 h in an individual bay with tight head restraint (50 cm short-rope) or loose head restraint (95 cm long-rope). Behavioral parameters relating to head position, eating, and stress were monitored during transportation. Tracheal wash samples were obtained 6 days before and immediately after transport for bacterial culture a...
Pereira AT, Pozzobon R, Dos Anjos BL, Kunz AR, Chaves LT, Smilgys EC, Andrade BDS, Lunkes VL, de Andrade CM, Costa MM.Long-loop rodeo is a major competition for Criollo horses. We aimed to feature long-loop tournaments and to assess the profiles of competing horses. The animals (n = 49) were registered, and their body mass/scores, information about breeding, feeding, and training management, loaded weight, and tournament track (n = 11) were collected; speeds reached were estimated. Heart and respiratory rates of horses (n = 27) were collected before the tournament, on the final day of the event, and 18-24 h after the end of the tournament. Blood samples were collected from the animals at the same time. Blood ...
Otsuka T, Araki M, Mita H, Kambayashi Y, Yoshihara E, Ohta M.We evaluated the clinical efficacy of total intravenous anesthesia (TIVA) with propofol-ketamine-xylazine (PKX) with or without remifentanil for castration in horses. Twenty-four Thoroughbred horses were premedicated with intravenous (IV) xylazine (1.0 mg/kg) and midazolam (0.02 mg/kg) and anesthetized with IV ketamine (1.5 mg/kg) and propofol (1.0 mg/kg). Surgical anesthesia was maintained with constant infusion of propofol (3.0 mg/kg/hr)-ketamine (3.0 mg/kg/hr)-xylazine (1.0 mg/kg/hr) (group PKX: n=8), PKX combined with remifentanil (3.0 µg/kg/hr) (group PKXR3: n=8), or PKX combined with re...
Vokes JR, Lovett AL, de Kantzow MC, Rogers CW, Wilkins PA, Sykes BW.Viscoelastic monitoring of horse coagulation is increasing due to its advantages over traditional coagulation testing. The use of a point-of-care viscoelastic coagulation monitor (VCM Vet™) has been validated for use in horses using native whole blood (NWB) but has not been assessed using citrated whole blood (CWB), a technique that might have advantages in practicality and precision. Blood was collected from 70 horses, tested in duplicate immediately using NWB (T0), and stored at room temperature as CWB for testing in duplicate at 1 (T1) and 4 (T4) hours after venipuncture for comparison to...
In this paper, we report a comprehensive and consistent annotation of the locus encoding the β-chain of the equine T-cell receptor (TRB), as inferred from recent genome assembly using bioinformatics tools. The horse TRB locus spans approximately 1 Mb, making it the largest locus among the mammalian species studied to date, with a significantly higher number of genes related to extensive duplicative events. In the region, 136 TRBV (belonging to 29 subgroups), 2 TRBD, 13 TRBJ, and 2 TRBC genes, were identified. The general genomic organization resembles that of other mammals, with a V cluster o...
Tuniyazi M, Tang R, Hu X, Zhang N.Laminitis is a serious health condition that can cause severe pain and lameness in horses. Due to lack of understanding of laminitis, treatments often fail to achieve the desired results. In recent years, we have begun to recognize that laminitis may involve a complex interaction between local and systemic inflammation. Dysbiosis of the gut microbiota has been linked in the development of systemic inflammation, and our previous findings suggest that the development of laminitis is closely linked to the production of harmful metabolites of the gut microbiota. In addition, it was found that loca...
Yoshihara T, Tozaki T, Nakaya S, Takasu M, Kawate K, Furukawa R, Kikuchi M, Isihge T, Nagata SI, Kakoi H, Hobo S.The Taishu horse is a native Japanese breed threatened with extinction. It is important to genotype the causative genes of rare phenotypes in endangered breeds because unique genetic traits might be lost unless a breeding strategy for conservation is constructed. In the present study, nine single-nucleotide variants and three indels of nine genes related to coat color, body composition, and gait were genotyped in 56 Taishu horses. Of these, only three genes were polymorphic. The observed coat color phenotypes coincided with the estimated phenotype from the genotypes, whereas black horses showe...
Chaintoutis SC, Diakakis N, Polizopoulou ZS, Dovas CI.Serum protein electrophoresis (SPE) is widely used to evaluate protein changes associated with several pathologies, aiming to assist clinical diagnosis. This study aimed to determine, for the first time, SPE profile changes in WNV-naturally infected horses. Sixty horses with different clinical and infection status (encephalitis, asymptomatic infection, and immunologically naïve) were included. Total protein concentrations were determined via an automated biuret method and SPE was performed using a cellulose acetate membrane-based automated system. Statistical analysis revealed significantly h...
Gibson OL, Zhao S, Adam E, Stowe CJ.The objective of this study was to estimate the price elasticity of demand for 3 common equine veterinary services: vaccinations (a routine service), lameness examinations (an elective service), and emergency colic surgery (an urgent service). Methods: Data were collected via a nationwide online survey of horse owners from August 15 to September 11, 2023, eliciting their willingness to pay for each service. The link to the online survey was distributed through participating organizations' social media and email lists to the target audience of US residents aged ≥ 18 years who were financially...
Rodrigues GG, Alves DS, Bromberger CR, Nomelini QSS, Borges AS, de Oliveira-Filho JP, Delfiol DJZ.The association between aural plaques, Equus caballus papillomavirus (EcPV), and the different breeds of horses and risk factors is poorly described. The objective of this study was to determine the clinical prevalence of aural plaques in Mangalarga Marchador (MM) and Quarter Horse (QH) horses in Brazil, to evaluate the association of this prevalence with some risk factors, and to detect the presence of EcPV DNA (types 1-10) in aural plaques biopsies. A total of 400 MM and 425 QH horses, were clinically evaluated. For each horse, an identification form was completed, containing information on ...
Allen R, Goodhead AD.Warmblood horses are a popular breed around the world for equestrian sports. Previous studies have investigated ocular findings in other breeds of horses; however, no studies exist for the Warmblood breed. Objective: To determine the prevalence of ocular abnormalities in a convenience sample of Warmblood horses in South Africa and to determine if the prevalence of lens and chorioretinal lesions increase with age. Methods: Descriptive, observational study. Methods: Warmblood horses underwent a full ophthalmic examination which included a Schirmer tear test (STT), tonometry, fluorescein dye test...
Nomura M, Kuroda T, Ohta M, Kusano K, Minamijima Y, Nagata S.Salbutamol is a short-acting and selective beta-2 adrenergic agonist. Inhaled (IH) administration of salbutamol is widely used to control lower respiratory tract disease in horses. Here, we estimated the pharmacokinetic parameters of salbutamol after a single intravenous (IV) or IH administration in six horses, and we statistically analysed the detection times with various dosing regimens. Plasma and urine concentrations of salbutamol were measured by liquid chromatography-tandem mass spectrometry, and data were modelled by using a nonlinear mixed effect model followed by Monte Carlo simulatio...
Elbourne M, Keledjian J, Cawley A, Fu S.Altrenogest, also known as allyltrenbolone, is a synthetic form of progesterone used therapeutically to suppress unwanted symptoms of estrus in female horses. Altrenogest affects the system by decreasing levels of endogenous gonadotrophin and luteinizing and follicle-stimulating hormones, which in turn decreases estrogen and mimics the increase of progesterone production. This results in more manageable mares for training and competition alongside male horses while improving the workplace safety of riders and handlers. However, when altrenogest is administered, prohibited steroid impurities su...
Sousa LN, Winter IC, Varela DD, Luvison EZ, Guzmán JFC, Machado AMV, Figueiredo RDV, Pena GT, Dos Santos ACS, Faleiros RR, Carvalho AM.The present study involved seven horses in a randomized crossover clinical trial to evaluate the effect of lidocaine on horses with induced endotoxemia. Horses received intravenous lidocaine (1.5 mg/kg bolus, followed by 0.05 mg/kg bwt/min) or placebo (0.9% sodium chloride at the same manner) one hour before LPS administration (0.03 μg/kg, IV infusion over 30 min). We monitored clinic and hematologic parameters, abdominal auscultation, ultrasound, and pain over time. No relevant clinical differences existed between treatments regarding peristalsis, abdominal pain, or any other parameters befo...
