Ultrasound in horses is a diagnostic imaging technique that utilizes high-frequency sound waves to produce images of the horse's internal structures. It is commonly used in veterinary medicine to evaluate soft tissues, tendons, ligaments, and organs. This non-invasive method allows for real-time visualization of physiological and pathological conditions, aiding in the diagnosis and management of various equine health issues. Ultrasound is particularly valuable for assessing musculoskeletal injuries, reproductive health, and abdominal conditions in horses. This page compiles peer-reviewed research studies and scholarly articles that explore the application, methodology, and advancements in ultrasound technology within equine veterinary practice.
Ginther OJ.Movement of the conceptus within the uterine lumen of barren mares was studied by daily ultrasound examinations on days 11-20 and by rectal palpation on days 15-48 (Experiment 1) and by ultrasound examinations 3 or 4 times per day at 2-4 hour intervals on days 11-16 (Experiment 2). In addition, broodfarm records were analyzed to compare side of ovulation with side of embryo attachment (Experiment 3). The vesicle was found in opposite uterine horns for 43% of the successive, daily, ultrasound examinations on days 11 and 12, 12 and 13, 13 and 14, and 14 and 15; 24% of the successive examinations...
Ginther OJ.Fixation and orientation of the conceptus within the uterine lumen of 40 barren mares were examined by ultrasound daily on days 11-21 and at three-day intervals thereafter until day 48. The growth curve of the in situ conceptus had a distinct plateau between days 17-24, as determined by measurements of the width and area of conceptuses on the ultrasound images. The vesicle expanded at an average daily rate of 3-4 mm before the plateau and 2-3 mm after the plateau. Dramatic changes occurred in the shape of conceptus. The predominant shapes were approximately as follows: days 11-16, spherical; d...
Proctor PT.This study discusses a case of foetal abnormality resembling schistosomus reflexus in a thoroughbred mare, noting its similarity to documented instances in bovines and pointing towards the need for more […]
Simpson DJ, Greenwood RE, Ricketts SW, Rossdale PD, Sanderson M, Allen WR.In 1981 a trial was conducted on 6 Newmarket Thoroughbred stud farms into the use of real-time ultrasound echography (scanning) as an aid to the early diagnosis of pregnancy in the mare. The procedure was found to be practicable and interpretation of the findings was relatively straightforward. Pregnancy was positively diagnosed from as early as 14 days after ovulation and a number of twin pregnancies were recognized, some in which the conceptuses were situated in separate horns of the uterus but an almost equal number in which the conceptuses were together in the same horn. It was concluded t...
Parry BW, McCarthy MA, Anderson GA, Gay CC.The influence of occlusive bladder width on blood pressure, measured indirectly using a doppler ultrasound technique at the middle coccygeal artery, was studied in 6 anesthetized horses. The relationship was investigated on tails with and without hair, and the optimum bladder width (BW)/tail girth (TG) ratio was determined for systolic pressure (SP) and diastolic pressure (DP), with the data grouped as unclipped tails (TT-1), clipped tails (TT-2), and both unclipped and clipped tails collectively (TTB). The optimum BW/TG ratios for SP and DP were 0.296 and 0.866 for TT-1, 0.376 and 1.156 for T...
Lang DC.A beam of pulsed ultrasound was used to treat musculoskeletal disorders in 53 horses and 143 dogs and cats. The cases were spread over seven years and 533 separate insonations were made. Doses, which varied according to the lesion, ranged from 0.2 to 3 watts/cm2 for five minutes in each treatment. In 63 per cent of the cases, rapid and complete resolution occurred.
Hurtgen JP, Whitmore HL.Luteolysis, estrus, and ovulation were induced by endometrial biopsy during three periods of prolonged diestrus in two mares. Serum progesterone concentrations decreased to less than 1 ng/ml within 48 hours after biopsy. Mares were in estrus within 3 days after endometrial biopsy. It was concluded that endometrial biopsy may induce regression of the persistent corpus luteum by stimulating the release of an endogenous uterine luteolysin (prostaglandin).
Johnson JH, Amend JF, Franklin D, Garner HE.Ultrasonic dimension gauges were implanted in the crico-arytenoideus dorsalis muscle in a mature horse. Resting and contracted muscle length and average contraction rate were measured serially in the conscious state over a period of 25 days. Results suggest that specific laryngeal muscle function in the horse may be defined with this approach. Since man and horse are both known to suffer from laryngeal hemiplegia, this experimental preparation may help provide information of benefit to both species.
Pipers FS, Hamlin RL.Echocardiograms were obtained from 25 standing, clinically normal horses, using an ultrasonic recording device. The echobeam penetrated the right thoracic wall in the area of the 4th to 5th intercostal space, with a frequency of 2.5 mHz. Measurements of left ventricular wall thickness generated a mean value of 3.2 +/- 0.18 (SEM)cm, whereas the left ventricular chamber diameter in diastole was 9.3 +/- 0.30 cm and in systole was 5.7 +/- 0.23 cm. The aortic root dimensions had a mean of 7.7 cm, with a SEM of 0.16. Mitral valve closing slope (E-F) was calculated to be 17.7 +/- 0.87 mm/second, and ...
Gay CC, McCarthy M, Reynolds WT, Carter J.A method using the Doppler ultrasound principle for indirect determination of arterial blood pressure in the horse is described. The method is simple and suitable for field situations. Validation studies show that systolic and diastolic blood pressure measurements bear a close relationship to true values obtained by direct measurement.
Vitums A, Grant BD, Stone EC, Spencer GR.ABSTRACT Transposition of the aorta to the right ventricle with atresia of the pulmonary trunk was described in a 2 year old horse. Clinical and physiological examinations were performed and data recorded. Teratogenesis of the present anomaly was discussed and the literature reviewed. The probable course of circulation during the fetal life and after birth of this animal was suggested. An extensive col-lateral circulation was developed to the lungs, which might explain how the animal could live so long.
A 25-year-old pony mare was presented to the clinic with preliminarily reported severe acute colic. The pony during the previous week had shown inappetence, apathy and fever of unknown origin. Clinical examination and placement of a gastric tube were indicative of a secondary gastric dilation. Rectal exploration found moderate caecal meteorism with a tensed and painful medial taenia as well as a dilated and fluid-filled small intestine. In addition, a solid, mobile, non-painful structure of approximately 10 cm diameter was palpated ventrally. A hyperechogenic mass close to the caecum was detec...
Angyal E, Vincze B, Somoskői B, Sós-Koroknai V, Balogh P, Dankó GN, Cseh S, Kútvölgyi G.The anti-Müllerian hormone (AMH) is a granulosa cell-derived hormone that has been associated with female fertility and reflects the population of growing follicles. This study aimed to evaluate the average concentration of AMH in Lipizzaner mares, as well as to determine the relationship between AMH concentration and follicle number and size. We also investigated the relationship between the age of mares and their AMH levels. The possible effect of seasonality of AMH levels was also assessed. Twenty-three mares between 6 and 24 years of age were included in the experiment. Mares were divided...
Fischetti L, Perina F, Sarli G, Ellero N, Freccero F, Castagnetti C, Mariella J.A 286-day pregnant mare was referred for signs of impending abortion. The ultrasonographic evaluation revealed a high normal combined thickness of the utero-placental unit (CTUP), oligohydroallantois and a living fetus. No vulvar discharge was observed, and the cervical swab culture was negative. After a choke, the mare received NSAIDs and antibiotics and then developed systemic inflammatory response syndrome (SIRS) and aborted. The amniotic portion of the umbilical cord was excessively long and twisted and the chorionic side of the placenta showed a brown discoloration and rough surface area....
Maria Feitosa Ribeiro L, Bersot Gomes JV, Hernando Ortiz Vega W, da Silva Alves A, Netto Machado M, Junio Wutke L, Raquel Quirino C....Stallion breeding is mostly based on desirable phenotypic traits, with little consideration for semen quality. Objective: To identify relationships among semen parameters in stallions using a non-invasive, integrative approach across summer and winter seasons. Methods: Twenty-four stallions were evaluated, in which semen collections, testicular thermography, and Doppler velocimetry of the testicular artery by Doppler ultrasonography were performed, in addition to the measurement of physiological, environmental, and heat stress parameters, both in winter (coat weather) and summer (T-shirt weath...
Huggins L, Dini P, Santos E, Dujovne G.A Gypsy Vanner stallion presented with a history of subfertility and abnormal dense, grey ejaculate. Reproductive examination including ultrasound, cytology, and bacteriology confirmed the diagnosis of seminal vesiculitis. After evaluation of several ejaculates, bilateral blocked ampullae were confirmed by azoospermia and a low level of alkaline phosphatase (30 IU/L) in the filtered fraction. Continuous semen collections, along with oral antibiotics treatment, were performed at the owner's facility for five weeks. After readmission, a successful collection was obtained with a high concentratio...
Urion R, Lustgarten M, Hostnik ET.Technological developments in imaging modalities have advanced the diagnostic capabilities for equine tendon and ligament injuries beyond the traditional methods. This review examines elastography techniques in ultrasonography that assess tissue stiffness and strain properties, computed tomography (CT) innovations including PET/CT fusion and dual-energy CT, and emerging applications of diffusion-weighted MRI for evaluating fiber microstructure and functionality. These complementary approaches offer veterinarians improved means to detect early injuries, assess structural integrity, monitor heal...
Amari M, Brioschi FA, Auletta L, Ravasio G.Radiofrequency ablation (RFA) and pulsed radiofrequency (PRF) are non-pharmacological techniques employed in humans for chronic pain, but their veterinary application is unexplored. This pilot study evaluated clinical effects of RFA and PRF in twenty-four horses with chronic distal forelimb lameness. Ultrasound-guided RFA (N = 8; 60-90 °C, 2-8 min) or PRF (N = 16; 42 °C; 12 min) was applied to palmar digital nerves. Lameness was scored (American Association of Equine Practitioners scale) at baseline and monthly for six months (T1-T6). At T2, partial- and non-responders in both groups receive...
Raidal SL, Freccero F, Carstens A, Weaver S, Padalino B.Transportation of horses has been associated with colic and changes to the gastrointestinal microbiome. Percutaneous abdominal ultrasonography using wireless, point-of-care transducers can be used to assess gastrointestinal motility in field settings. Unassigned: Characterization of intestinal motility and salivary cortisol responses of horses completing commercial transportation of 10-12h. Unassigned: Prospective observational study of 30 horses with diverse signalment and transport histories. Clinical parameters, sonographic assessment of intestinal motility and saliva samples, were collecte...
Gutierrez SO, Garcia-Lopez JM, Chope KB, Levine DG, Ortved K, Brown KA.To describe the clinical and ultrasonographic findings in horses with desmopathy of the abaxial palmar/plantar ligament (APL) of the proximal interphalangeal joint and the prevalence of concurrent musculoskeletal injuries in the pastern and foot. Unassigned: Horses presenting to New Bolton Center between March 2017 and November 2022 with an age ranging from 5 to 20 years that underwent lameness evaluation in which lameness was localized to the distal limb and had an ultrasonographic diagnosis of APL desmopathy. Unassigned: Horses included were those that (1) presented for a lameness examinatio...
Marques GF, Moorman VJ, Ellis KL, Perlini M, Edwards VL.To describe the long-term outcome of a horse that underwent a standing, ultrasound-guided, minimally invasive, biceps brachii tenotomy. Methods: Case report. Methods: A 17-year-old Tennessee Walking Horse gelding. Methods: The horse had a chronic, severe, lameness localized to the left shoulder region. Diagnostic imaging revealed fractures of the intermediate and lesser tubercles of the left humerus, biceps brachii (BB) tendinopathy, and bicipital bursitis. Conservative management was attempted, but lack of improvement prompted surgical intervention. An ultrasound-guided, minimally invasive, B...
Samsel J, Gündemir O, Szara T, Witkowski M.Uterine torsion in mares belongs to maternal pregnancy disorders, accounting for 5-10% of complications in the last trimester of pregnancy. Two surgical techniques for repositioning uterine torsion are used: flank laparotomy in local anesthesia on a standing mare (SFL) and midline laparotomy carried out under general anesthesia (MI). The study aims to present the exact protocol used by the authors to qualify a mare with uterine torsion for surgery using one of the above-mentioned methods.A total of 19 mares were operated on, of which 13 underwent midline laparotomy under general anesthesia, an...
Tommasa SD, Raspe S, Farí G, Imperante A, Brehm W.Tendon and ligament injuries in equine athletes pose significant challenges, often leading to prolonged recovery, reduced performance, and increased risk of reinjury. Current treatment strategies, including conservative and surgical approaches, have shown limited success in fully restoring tendon integrity. Autologous blood derivatives, such as autologous conditioned serum (ACS), have emerged as potential regenerative therapies. However, the clinical efficacy of ACS in the treatment of equine tendinopathies remains under investigation. Unassigned: This study aimed to compare the clinical outco...
Thomé C, Márquez-Moya A, Sala-Ayala L, Carreras-Vico N, Cuervo-Arango J.Post-mortem oocyte collection serves to preserve the genetic material of valuable mares and to obtain recipient oocytes for cloning purposes. Therefore, the number of oocytes retrieved per ovary is a critical factor in increasing the likelihood of obtaining a viable embryo. This study evaluated the efficiency of two post-mortem oocyte retrieval techniques: follicular scraping (Scraping) and ultrasound-guided follicular aspiration (OPU). The comparison was based on several parameters, including the number of follicles aspirated per ovary, oocyte recovery rate (ORR), number of oocytes obtained p...
Scala E, Durie I, Gommeren K, Saegerman C, van Galen G.(1) Background: Ultrasonography of major vessels helps evaluate fluid status and responsiveness in critical human and canine patients. Aims: transrectal and inguinal ultrasonography of caudal vena cava (CVC), aorta (Ao), and femoral artery (FA) and vein (FV) in horses; calculate CVC collapsibility index (CI CVC) and vein-to-artery ratios; compare B- and M-mode; and evaluate repeatability and reproducibility. (2) Methods: B-mode and M-mode video loops were recorded twice by transrectal (Ao, CVC) and inguinal ultrasonography (FV, FA) by two operators on 17 healthy, sedated adult horses. Diameter...
Nocera I, Moroni R, Fanelli D, Rota A, Di Franco C, Ungari C, Puccinelli C, Gandini M, Giusto G, Vannozzi I.Over the years, various diagnostic and surgical techniques have been developed to recognise and treat cryptorchidism in equid. This study retrospectively analysed cases of cryptorchidism referred to two centres between 2012 and 2025. Clinical data collected included species, breed, age, gender, location of retained testis, diagnostic approach, anaesthesia plan and surgical treatment, perioperative medical treatment, intra-operative complications and outcomes. A total of 37 clinical cases were included, 1/37 was a donkey and 1/37 was an intersex female. Most of the horses were three years old a...
Braga C, Prazeres J, Borges J, Ribeiro G.To noninvasively characterize skin thickness and elasticity in healthy horses using B-mode ultrasound and shear wave elastography (SWE) and to verify whether there are differences between the skin of stabled and outdoor horses. Unassigned: 10 clinically healthy horses were enrolled in this study. Five animals were housed exclusively indoors (indoor group), and 5 had temporary or permanent access to an outdoor environment (outdoor group). All horses underwent bilateral ultrasonographic examination of 3 anatomical regions: neck, withers, and girth region caudal to the elbow. Skin thickness was a...
Roxon CA, Deacon LJ, Abraham M, Stefanovski D, Sertich PL.Gestation length is not a reliable indicator of fetal maturity due to the variability of normal gestation length in the mare. A standard method to accurately predict equine fetal maturity is not being used clinically. The presence of continuous gastrointestinal peristalsis, as detected ultrasonographically, is an indicator that both human and canine fetuses are mature (can survive after elective cesarean section). To determine if continuous gastrointestinal peristalsis, which we termed Phase 5, was a valid indicator of fetal maturity in the horse, and whether this indicator varied in late-gest...
Ostendarp C, Barton AK.Intraocular neoplasia in horses is rare and only few case reports and small case series exist. Intraocular neoplasia has various clinical signs and includes important differential diagnoses in ocular disease. This narrative review of the current literature aims to provide a clinically relevant overview and classification of intraocular tumors in horses and adds a comparative oncological perspective concerning diagnosis, treatment and future considerations. The available clinical and imaging examination techniques allow for a reliable and differentiated investigation of the tumor, even in the s...
Ali A, Derar DR, Alaeyeari AA, Alharbi YM.This study aimed to monitor intrauterine fetal growth, establish predictive equations for gestational age estimation, and determine the optimal period for fetal sexing in Arabian horses using ultrasonography. Unassigned: Seven Arabian mares were monitored from insemination to parturition using transrectal ultrasonography. The following fetal and embryonic parameters were measured: embryonic vesicle (EV), crown-rump length (CRL), biparietal diameter (BIP), stomach diameter (STD), chest depth (CHD), abdominal diameter (ABD), kidney length (KDL), eyeball diameter (EBD), and eye lens length (ELL)....
Serighelli-Júnior G, Strugava L, de Oliveira Franco JD, Kulik K, Dornbusch PT, Machado M, Moreno JCD.To describe the detailed anatomy of the equine thoracoabdominal region and to compare the accuracy of ultrasound-guided versus blind intercostal nerve injection techniques, targeting the thoracic intercostal nerves (T12-T18) in equine cadavers. Methods: Randomized, blinded, cadaveric study. Methods: Eight fresh adult equine cadavers. Methods: Eight horse cadavers were used: one in phase I (436 kg; 4 years old) for anatomic landmarks identification and seven in phase II [420 (317-560 kg); 16 (3-22 years old) [median (minimum-maximum)] for comparative study. In phase I, dissections were performe...
Góss GC, Mozzaquatro FD, Machado IRL, Gomes EM, Martins NR, Duarte CA.The collateral ligaments of the distal interphalangeal joint (CL-DIPJ) are important structures for athletic horses. Ligament injuries can cause lameness, but ultrasound imaging can detect such lesions, which usually present with changes in echogenicity and an increase in the cross-sectional area (CSA) of the ligament. Measurements of these structures vary among authors, which complicates the diagnosis. Thus, this study aimed to describe the ultrasound measurements (dorsopalmar diameter [DPD], lateromedial diameter [LMD], and CSA) of the CL-DIPJ in Argentine Polo horses. We measured the CL-DIP...
Sala-Ayala L, Cuervo-Arango J, Martínez Boví R.Endometrial edema is an ultrasonographic sign of estrus in mares and is positively associated with fertility. This study aimed to evaluate the influence of follicular size, systemic progesterone (P4), and exogenous estradiol benzoate (EB) on the onset and duration of endometrial edema. In Experiment 1, anestrus (n = 4) and diestrus mares (n = 4) received 4 mg of EB intramuscularly; edema scores and plasma P4 were monitored over four days. In a complementary group (n = 5), mares were monitored until ovulation, then administered 4 mg of EB and examined every 12 h for 48 h. In Experimen...
Ellero N, Maggi A, Busoni V, Imposimato I, Castagnetti C, Lanci A, Mariella J, Freccero F.This study aimed to develop a standardized ultrasound (US) protocol using selected thoracic and abdominal acoustic windows, to assess its feasibility and applicability in healthy foals, and to evaluate its usefulness for detecting common thoracic and abdominal conditions in sick foals. The Focused US (FUS) protocol included 12 thoraco-abdominal windows (4 right-side, 3 ventral, 5 left-side) using a curved-array probe. It was applied to cohorts of healthy (n = 17) and sick (n = 23) foals by a veterinary clinician with limited US experience. The FUS showed good feasibility and applicabil...
Stoeckle SD, Stage HJ, Gehlen H.Thyroid diseases in horses are rare and pose challenges for veterinarians due to the complexity of clinical and diagnostic approaches. This retrospective case series describes cases of equine thyroid disease in a referral hospital population. Files of horses examined for suspected thyroid disease at an equine university clinic between 2009 and 2024 were reviewed. Data from nine horses examined for suspected thyroid disease, including signalment, clinical presentation, laboratory results, imaging findings, fine needle aspirates, biopsies, diagnoses, and treatments, were summarised. Diagnoses in...
Puccetti M, Beccati F, Pilati N.Femoral nerve neuropathy causes lameness, a condition clinically characterized by stifle's lack of extension with subsequent diminished lower limb function. This case report describes the ultrasonographic diagnosis of femoral neuropathy secondary to compression caused by myopathy of the iliopsoas muscle of an endurance horse during a competition. Transrectal ultrasonography played a pivotal role in diagnosis of the injury by assessment of the involved structures and monitoring of the healing process throughout the recovery period. The horse achieved complete recovery and successfully returned ...
Hansen T, Kendall A, Finne R, Law E, Ringdahl A, Nostell K.Abdominal ultrasound is widely used to evaluate the intestinal tract of horses. Despite being a routine examination, there is limited data on the reliability of this diagnostic procedure. Objective: To investigate intra- and inter-rater reliability of ultrasonographic intestinal wall thickness measurements in healthy horses. A second aim was to assess variance within repeated measurements to determine threshold values that distinguish whether differences between repeated examinations are true findings versus solely due to measurement variation. Methods: In vivo reliability study. Methods: Eigh...
Valente TC, Mendes RP, Miguel EL, Rafael LA, Ribeiro GSN, Souza AF, Fonteque JH.Regional intravenous limb perfusion (RILP) is widely used in equine practice for achieving high local antimicrobial concentrations while minimizing systemic exposure. However, certain drugs, including enrofloxacin, have been associated with vascular irritation and thrombosis, and their thrombogenic potential remains poorly characterized. Objective: This study aimed to evaluate the thrombogenic potential of enrofloxacin administered via RILP in the cephalic vein of clinically healthy horses. Methods: Ten adult horses underwent RILP in both forelimbs: the right limb received 10 % enrofloxacin (1...
Freitas Silva D, Passagli Barbosa D, de Paula Rodrigues J, Robaina Sancler-Silva YF, Saules Ignácio F, Lucena Fredou M, Segabinazzi L, Monteiro GA.Doppler ultrasonography is a valuable tool for monitoring testicular hemodynamics, offering improved diagnostic insight and supporting treatment monitoring. However, its use in equine andrology remains limited due to a scarcity of published data and reference values. Therefore, this study aimed to characterize the testicular arterial blood flow patterns in clinically normal stallions and stallions with 180° spermatic cord torsion. Spectral Doppler ultrasonography was performed on both testes of 48 Mangalarga Marchador stallions. Thirty stallions with normal testes were divided into three age ...
Nocera I, Di Franco C, Sorvillo B, Aliboni B, Bucchioni E, Sgorbini M, Sala G, Citi S.Ultrasound-guided local anaesthesia is commonly used in veterinary orthopaedics for horses. This study aimed to assess an ultrasound technique for the medial branch of the dorsal branch of the cervical spinal nerves (MB-DBCSNs) in horses and compare the performance of clinicians with different experience levels. Ten healthy, skeletally mature horses were examined using radiographic and ultrasound (US) techniques in the cervical area (C3-C7). Four operators with varying experience conducted US examinations using a 10 MHz linear and 6 MHz curvilinear transducer over ten training sessions. T...
Dufourni A, Demeyere M, Vera L, van Loon G, Decloedt A.This study aimed to compare two-dimensional, M-mode, color, pulsed-wave Doppler (PWD) and continuous-wave Doppler (CWD) echocardiography, and PWD ultrasonography of the caudal common carotid artery (CCA) in horses with aortic regurgitation (AR). Methods: Warmblood horses without (n = 20) and with mild, moderate, and severe AR (n = 60) were included in the study. Methods: A retrospective descriptive study focused on cardiac dimensions, aortic and CCA Doppler flow. Non-invasive blood pressure and presence of ventricular arrhythmia were recorded. Groups were compared using analysis of varianc...
Vázquez Bringas FJ, Porcar LB, Franco SF, Martinez CM, Lasheras AR, Moraiz AV.Transrectal palpation (TP) is a basic skill in equine practice. Traditional TP learning methods include instructor-assisted TP in live animals, but this approach presents animal welfare concerns, especially when it needs to be used with large numbers of students. The main objective of this study is to compare two learning methods of TP: traditional methodology with live horses (LH) and alternative methodology using a cadaver with its flanks dissected (CDV). Twenty students with no previous equine TP experience were randomly assigned to two groups: LH ( = 10) and CDV ( = 10). Both groups receiv...
