Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Trostle SS, Wilson DG, Stone WC, Markel MD.The purposes of this study were to mechanically determine the optimal tissue bite size and to evaluate seven suture materials at their largest commercially available size for breaking strength and stiffness using cadaveric adult equine linea alba. Soft tissues were removed from the abdominal fascia of 16 adult horses. Individual test sections were created from the entire linea alba and labeled (1 through 6) starting at the umbilicus and extending craniad. A single biomechanical test was performed on each test section. Tissue bite size (3, 6, 9, 12, 15, 18, and 21 mm) significantly altered brea...
Holcombe SJ, Robertson JT, Richardson L.A 4-year-old Thoroughbred filly was referred for evaluation of a soft palate defect that had been created several weeks earlier during surgical correction of epiglottic entrapment, performed transorally. Surgical correction of the defect was performed via mandibular symphysiotomy. At 85 days after repair, the horse raced successfully. A 2-year-old Thoroughbred filly was admitted for evaluation and treatment of epiglottic entrapment. The soft palate was lacerated during transnasal division of the entrapping membrane. A 2-cm full-thickness soft palate laceration was repaired transorally.
Asahina M, Murakami K, Ajito T, Goryo M, Okada K.The tissues of an 8-year-old thoroughbred castrated male horse with equine lymphoma were examined immunohistochemically. Neoplastic masses were observed in the mediastinum, mesenteric lymph nodes, gastric mucosa and serosa, liver capsule, and spleen capsule with associated lymph nodes. Histopathologically, the neoplastic cells were seen to consist predominantly of a mixture of well differentiated small and large types. Immunohistochemically, the small lymphoid cells were MHC class IIlow+ and PanT- and the large lymphoid cells were MHC class IIhigh+ and PanT-. These findings revealed that the n...
Dalefield RR, Palmer DN, Jolly RD.Lipofuscin accumulation and other histological changes in thyroid tissue, previously reported to be age-related, were studied in 31 horses aged up to 35 years. The number of lipofuscin granules relative to thyrocytes increased from birth to 5 years of age. There was a wide individual variation in the number of lipofuscin granules in thyrocytes in mature horses, but this was not directly related to age. Several abnormalities were identified in thyroid colloid. The prevalence of spherites, lipofuscin granules, nucleated cells and shreds of colloid increased with age, but the prevalence of calciu...
Smith RK, Jones R, Webbon PM.Fifty-two animals, comprising 22 Irish Draught crosses (Group A), 15 Thoroughbreds (Group B) and 15 ponies (Group C) were examined ultrasonographically using a 7.5 mHz linear array probe and stand-off pad. All animals were free of tendon disease as determined from clinical and ultrasonographical examination. The superficial (SDFT) and deep (DDFT) digital flexor tendons were scanned at 7 transverse (axial) levels between the carpus and metacarpophalangeal joint. Each transverse image was digitised using a commercially available frame grabber and the cross-sectional areas of each tendon at each ...
Ichinose T, Miller MG, Shibamoto T.Free malonaldehyde formed in the microsomes prepared from livers of monkey, rat, rabbit, mouse, cow, pig, dog, sheep and horse upon CCl4 oxidation was derivatized by reaction with N-methylhydrazine to form 1-methylpyrazole which was subsequently analyzed by capillary gas chromatography. Among the livers from animals tested, the monkey and rat livers produced the most malonaldehyde upon CCl4 treatment. Horse liver showed the greatest resistance to CCl4 oxidation. The gas chromatography method used in the present study exhibited an accurate and specific measurement of free malonaldehyde that mig...
Marr CM.Echocardiography is an extremely versatile tool for both the equine clinician and physiologist. There are three useful forms of echocardiography, B mode, M mode and Doppler. Together they provide complementary information on cardiac disease and haemodynamic status. B mode is used to image the cardiac chambers, valves, myocardium and pericardium. M mode allows determination of motion of cardiac structures; it is superior to B mode for timing of events and it is used to make precise measurements of the heart. Doppler echocardiography can assess intracardiac blood flow and its velocity. Echocardi...
Les CM, Keyak JH, Stover SM, Taylor KT, Kaneps AJ.The purpose of this study was to investigate the relationships between data obtained from quantitative computed tomography and mechanical properties in the equine metacarpus, as measured in vitro in bone specimens. Three hundred and fifty-five bone specimens from the metacarpi of 10 horses were machined into right cylinders aligned with the long axis of the bone. A computed tomographic scan of the specimens, along with a Cann-Genant K2HPO4 calibration standard, was obtained. The specimens then were compressed to failure, and the elastic modulus, yield stress, yield strain, strain energy densit...
Lapointe JM, Vrins A, McCarvill E.Sixty Standardbred horses, aged 3 to 10 years, were examined endoscopically for exercise-induced pulmonary haemorrhage (EIPH) 1 h after racing, on at least 3 occasions. Racing time, finishing position and post exercise venous lactate concentrations were also recorded. Horses positive for tracheal blood on endoscopy were classified as having either grade 1 EIPH (one or a few spots of blood in the trachea), or grade 2 (stream of blood). Air temperature, relative humidity and air pollutant levels were recorded on each examination day. Of the 60 horses, 52 (87%) were EIPH-positive on at least one ...
Jorm LR, Love DN, Bailey GD, McKay GM, Briscoe DA.The genetic structure of beta-haemolytic Lancefield group C streptococci isolated from horses in Australia was examined by multilocus enzyme electrophoresis. The 249 isolates comprised 70 classified phenotypically as Streptococcus equi subspecies equi, 177 classified as S equi subspecies zooepidemicus and two which were unclassifiable. Forty-one electrophoretic types were identified which could be classified into three major clusters, A, B and C. Of the isolates, 178 fell into cluster B (types 4 to 22) and lay within a genetic distance of 0.36. Sixty-nine of the 70 S equi subspecies equi isola...
Sweeney CR, Rossier Y, Ziemer EL, Lindborg SR.Bronchoalveolar lavage (BAL) was performed on 16 horses to determine whether it caused local or diffuse inflammation in the lungs. In 7 horses, BAL was performed in both lungs twice, 48 hours apart. Although total cell counts of the BAL samples did not change significantly, there were increased numbers and percentage of neutrophils in the second lavage fluid samples. In 5 horses, BAL was performed in 1 lung and repeated 48 hours later in the same lung and in the corresponding airway in the contralateral lung. The absolute cell count and percentage of neutrophils were significantly (P = < 0....
Brinsko SP, Ball BA, Miller PG, Thomas PG, Ellington JE.This study was designed to investigate the development of day 2 embryos obtained from young and aged mares, co-cultured with oviductal epithelial cells obtained from mares in each age group in a 2 x 2 crossover design. Young, fertile mares (n = 19; 2-7 years of age) and aged, subfertile, mares (n = 16; 17-24 years of age) were used as embryo and oviductal epithelial cell donors. Embryos (n = 37) were collected from the oviducts 2 days after ovulation and were paired (embryos obtained from young mares with embryos obtained from aged mares) so that eight pairs were co-cultured with young mare ov...
Schirmer EC, Farooqui J, Polak PE, Szuchet S.Cell-substratum adhesion plays a crucial part in the cascade of events that control growth or turn on and consummate a differentiation program. We are investigating the molecular basis of oligodendrocyte (OLG) cytodifferentiation, employing pure cultures of OLGs isolated from postmyelination brains. We have shown that such OLGs will regenerate in vitro and reenact the ontogenic development of myelin, but to do so they need a signal. Adherence to a polylysine surface in the presence of 20% horse serum generates such a signal. Among the events that are turned on upon OLG adhesion is the phosphor...
Palmer JL, Bertone AL.The use of extremely small dosages of intra-articular E. coli lipopolysaccharide (LPS) endotoxin can create a model of synovitis that mimics acute synovitis in horses. Dosages of 5000 ng, 25 ng, 0.5 ng, 0.25 ng, 0.17 ng and 0.125 ng per joint were injected into various joints of a total of 6 horses. The dose response of LPS on clinical signs and synovial fluid parameters was evaluated at baseline and 12, 24, 36 and 48 h after LPS injection. Peripheral venous blood analysis was performed at baseline and at 0, 4, and 12 h after LPS injection. Dosages greater than 0.5 ng/joint resulted in clinica...
Arav A, Carney JN, Pease GR, Liu KL.This research study explores the process of cryopreservation of stallion semen, focusing on improving the thawing procedures using thermal hysteresis proteins (THPs) from Antarctic and Arctic fish in order to […]
Taddei N, Buck M, Broadhurst RW, Stefani M, Ramponi G, Dobson CM.The stability and equilibrium unfolding behaviour of horse muscle acylphosphatase have been studied by denaturing the protein under various conditions of temperature, pH, and urea concentration. Far-ultraviolet circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy indicate that this small monomeric protein unfolds reversibly and cooperatively. Thermodynamic parameters, the Gibbs free energy delta G and enthalpy delta H of unfolding, have been estimated for denaturation of the protein from NMR and CD data as 19 kJ mol-1 and 350 kJ mol-1, respectively. CD and 1H-NMR results s...
Kydd JH, Smith KC, Hannant D, Livesay GJ, Mumford JA.Twelve adult ponies and 2 conventional foals were exposed intranasally to EHV-1, strain Ab4 (TCID50 10(-6.6) and samples of respiratory tract associated lymphoid tissues were recovered between 12 h and 13 days after infection. Infectious virus was detected in tissue homogenates using susceptible cell monolayers and expression of viral antigens was monitored using indirect immunoperoxidase histochemistry on paraffin sections. The results showed both infectious EHV-1 and viral antigens in respiratory tract associated lymph nodes 12 h after exposure. Infected leucocytes were identified morphologi...
Hardy J, Bednarski RM, Biller DS.Pharmacologically induced splenic contraction might be useful during certain medical or surgical procedures in horses. The effects of phenylephrine, an alpha 1-adrenergic receptor agonist, on hemodynamic function and splenic dimensions were examined in 6 healthy adult horses. Phenylephrine infusion (1, 3, or 6 micrograms/kg of body weight/min for 15 minutes) resulted in a dose-related increase in mean pulmonary artery pressure; right atrial pressure; systolic, mean, and diastolic arterial pressures; and packed cell volume (P = 0.0001). Concurrent decreases in heart rate and specific cardiac ou...
Xu X, Arnason U.The sequence of the mitochondrial (mt) DNA of the horse (Equus caballus) was determined. The length of the sequence presented is 16,660 bp. This figure, however, is not absolute due to pronounced heteroplasmy caused by variable numbers of the motif GTGCACCT in the control region of different molecules. Boundaries of the 13 peptide-coding genes were determined by the presence of start and stop codons, and by analogy with other eutherian mtDNAs. Three genes (COIII, NADH3 and NADH4) were not terminated by a stop codon. Comparison among the peptide-coding genes of the horse and eight other mammals...
Théon AP, Pascoe JR, Meagher DM.Twenty-seven horses (and 1 mule) with 32 histologically confirmed cutaneous tumors were studied to evaluate the effects of intratumoral injection of cisplatin initiated at the time of surgery. As a result of surgery, 9 of the wounds were closed primarily (5 sarcoids, 4 carcinomas) and 23 were left open to granulate (16 sarcoids, 6 carcinomas, 1 hamartoma). Chemotherapy consisted of 4 treatment sessions of intratumoral injection of cisplatin in purified sesame oil at 2-week intervals. The first treatment session was administered intraoperatively. A controlled-release formulation of cisplatin in...
Claes A, Cuervo-Arango J, Colleoni S, Lazzari G, Galli C, Stout TA.The success of invitro embryo production (IVEP) in horses has increased considerably during recent years, but little is known about the effect of the speed of invitro embryo development. Blastocysts (n=390) were produced by intracytoplasmic sperm injection of IVM oocytes from warmblood mares, cryopreserved, thawed and transferred into recipient mares on Days 3, 4, 5 or 6 after ovulation. The time required for invitro-produced (IVP) embryos to reach the blastocyst stage was recorded (Day 7 vs Day 8). The likelihood of foaling was affected by the speed of invitro embryo development and recipient...
Wahdati A, Lindner A, Sommer H.The influence of temperature and duration of storage on glutathione peroxidase (GSH-Px) activity in plasma and whole blood samples of horses was investigated. Furthermore the relationships between the GSH-Px activities in plasma and whole blood as well as the GSH-Px values related to hematocrit and the hemoglobin content of the blood samples of 93 different horses were calculated. At 20-22 degrees C, the GSH-Px activity in plasma and whole blood samples remained stable over at least three days while it was reduced by 38% and 65% after 2 and 3 days, if the whole blood samples were kept stored a...
Timoney PJ, O'Reilly PJ, McArdle JF, Ward J, Harrington AM.Contagious equine metritis (CEM) was reproduced in 3 of 4 donkey mares with an Irish streptomycin-resistant strain of Haemophilus equigenitalis isolated from an experimental case of the disease in a pony mare. Although some variability in clinical response occurred, there was no evidence that semen enhanced the clinical severity of the infection. Variable amounts of vaginal discharge and associated inflammatory changes of the vagina and/or cervix, similar to those seen in the horse, were observed. All the affected donkeys made spontaneous clinical recoveries and so far as could be detected, su...
Thomsen LN, Berg LC, Markussen B, Thomsen PD.Cervical synovial folds have been suggested as a potential cause of neck pain in humans. Little is known about the extent and characteristics of cervical synovial folds in horses. Objective: The objective of this explorative study was to determine the frequency of synovial folds in equine cervical articular process joints and to provide a characterisation of the size and morphology of the synovial folds. Methods: Equine cervical articular process joints from 6 horses were included in the study, ranging from cervical vertebra 2 (C2) to cervical vertebra 7 (C7) bilaterally. The articular process...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the fruit of Mill. ssp. v var. (sweet fennel tincture) when used as a sensory additive in feed and water for drinking for all animal species. The product is a ■■■■■ solution, with a dry matter content of approximately 2.16%. The product contained 0.0586% polyphenols (of which 0.0052% were flavonoids), anethole (0.0006%), anisaldehyde (0.0035%) and estragole (0.0006%). The Panel on Additives and Products or Substances used in Animal Feed (FE...
Recknagel S, Snyder A, Blanke A, Uhlig A, Brüser B, Schusser GF.Knowledge of tetanus immunity in equine patients is crucial in cases of injuries, elective surgeries, or when effective vaccination protocols are to be designed. The Fassisi® TetaCheck is a stall-side rapid test which was developed to address these issues. The purpose of the present study was to evaluate its performance parameters. To this end, the qualitative test results obtained by two blinded observers were compared to tetanus toxoid antibody levels from 99 serum samples, measured with a double antigen ELISA. Additionally the colour intensities of the test window were quantified using a c...
Juarbe-Díaz SV, Houpt KA, Kusunose R.Separate surveys of Thoroughbred, Paint, and Arabian mare owners revealed a higher than expected rate of foal rejection in Arabian mares. A behavioural history form was submitted by owners of foal rejecting and nonrejecting Arabian mares, and maternal behaviour and management practices compared. Four generation pedigrees of rejecting and nonrejecting Arabian mares were also examined. Foal rejecting mares were more likely to avoid, threaten, squeal at, chase, bite, and kick their foals post partum than nonrejecting mares. Nonrejecting mares were more likely to lick, nicker and defend their foal...
Ball BA, Altschul M, Freeman KP, Hillman RB.Trophoblastic vesicles have been used to study early embryonic development and maternal recognition of pregnancy in domestic animals. The purpose of this study was to characterize the formation of trophoblastic vesicles from Day-12 to Day-16 equine conceptuses. Conceptuses (n = 19) were collected nonsurgically from mares, the capsule was removed, and the conceptus (trophoblast and inner cell mass) was dissected into 2- to 4-mm fragments. Conceptus fragments were cultured in either Ham's F10 (HF10) or Minimum Essential Media (MEM) with 10% fetal bovine serum (FBS) in 24-well plates. Plates were...
De Gasperi D, Guo D, Guo D, Lu Y, Brounts SH.To develop and describe a minimally invasive, ultrasound-guided, percutaneous technique for the desmotomy of equine palmar/plantar annular ligaments (PALs) using a transecting thread. Methods: Ex vivo study. Methods: Twenty-one normal equine distal limb specimens. Methods: Under ultrasonographic guidance, a surgical thread was percutaneously placed around the PAL through 2 skin punctures (proximal and distal) using a 18 gauge spinal needle in equine limbs (11 forelimbs, 10 hindlimbs) with normal PALs. The ligament was transected by a back-and-forth motion of the thread until the loop emerged...
Fernandez NJ, Roy MF.The plasma protein:fibrinogen (PP:F) ratio was introduced to aid interpretation of hyperfibrinogenemia by accounting for dehydration. However, this ratio is inconsistently assessed in practice and its clinical value remains unknown. Our objective was to determine whether the PP:F ratio provides additional information in adult horses beyond fibrinogen concentration alone. Two databases were reviewed to identify 412 hyperfibrinogenemic horses. Plasma protein:fibrinogen ratios were calculated and their interpretation compared to the fibrinogen concentration. Ratios < 15 were supportive of infl...
Coenen M.Ponies were fed hay (n = 21) or mixed feed (n = 27; 128 g crude protein, 175 g crude fibre/kg dry matter) for at least 14 days (treatment against parasites with ivermectin before the experimental period). The feeding level was 18 g dry mater/kg body weight/day. After the feeding period (the experiments were conducted to investigate the water and electrolyte content of the alimentary tract in dependence on feed, feeding time and physical exercise) the ponies were slaughtered and the stomachs were visually controlled for the occurrence of ulcers. In the hay group no gastric ulcers were observed,...
Ginther OJ.The estrous cycles of heifers and mares are used for illustrating pitfalls at the animal level in research in reproductive biology. Infrequent monitoring for characterizing the change in hormone concentrations or for detecting a reproductive event can be a pitfall when the interval for obtaining data exceeds the interval between events. For example, hourly collection of blood samples has shown that the luteolytic period (decreasing progesterone) encompasses 24 hours in heifers and mares. Collection of samples every 6-24 hours results in the illusion that luteolysis requires 2-3 days, owing to ...
Solinger N, Sonea IM.Tachykinins have profound effects on equine intestinal motility, but the distribution of the neurokinin receptors (NKRs) through which they act is unknown. This study reports the distribution of one of these receptors, the neurokinin-1 receptor (NK1R), in smooth muscle throughout the equine intestinal tract. Objective: To quantify the distribution of the NK1R, based upon mRNA expression, in smooth muscle of different regions of the equine intestinal tract. Methods: Nine regions of the intestinal tract were sampled in 5 mature horses. Total RNA was isolated from smooth muscle and reverse transc...
Panitz E.Ethyl-6-ethoxybenzothiazole-2-carbamate (Sch 18099) was evaluated for efficacy against natural helminth infections in ponies, pigs, lambs and chickens. Sixteen critical trials were conducted in ponies at dosages of 15 to 150 mg/kg. At 15 mg/kg, efficacy against adult and larval Oxyuris equi was 100% and 91% and against small strongyles it was 98%. Efficacy levels were 95% against Strongylus vulgaris and S. edentatus at the 20 mg/kg dosage. In two trials at 100 mg/kg efficacy against Parascaris equorum was 77%. No efficacy was observed against Gastrophilus spp. or Anoplocephala spp. In swine si...
van Wuijckhuise-Sjouke LA.Determination of the plasma fibrinogen concentration was found to be particularly useful in detecting inflammatory diseases. The highest levels were observed in inflammatory lesions of serous surfaces and in endocarditis. Plasma fibrinogen levels correlated with the severity of the disease: levels of 1,000 mg per 100 ml or more reflected a prognosis ranging from poor to bad.
Queiroz-Neto A, Zamur G, Carregaro AB, Mataqueiro MI, Salvadori MC, Azevedo CP, Harkins JD, Tobin T.Caffeine is the legal stimulant consumed most extensively by the human world population and may be found eventually in the urine and/or blood of race horses. The fact that caffeine is in foods led us to determine the highest no-effect dose (HNED) of caffeine on the spontaneous locomotor activity of horses and then to quantify this substance in urine until it disappeared. We built two behavioural stalls equipped with juxtaposed photoelectric sensors that emit infrared beams that divide the stall into nine sectors in a 'tic-tac-toe' fashion. Each time a beam was interrupted by a leg of the horse...
Schusser GE, White NA.To determine the number of myenteric plexuses and neurons in the large colon of clinically normal horses and whether the number was decreased in the large colon of horses with colon disease. Methods: Prospective study. Methods: Colon samples from 15 clinically normal horses and 31 horses with colon disease. Methods: Samples were obtained, fixed, and stained with H&E. The number of myenteric plexuses and neurons and longitudinal muscle thickness were determined in each segment of colon for clinically normal horses. Counts for segments were compared with each other and with counts in the sam...
Secombe CJ, Firth EC, Perkins NR, Bailey D, Anderson BH.To determine whether variation in x-ray-beam angle significantly affected photodensity of the third carpal bone (C3) in the horse using the tangential radiographic view, and indirectly determine whether radioabsorptiometry (RA) could be used to assess differences in bone mineral density (BMD) of C3 between exercised and non-exercised horses. Methods: The left distal carpal row was isolated post-mortem from 2-year-old Thoroughbred horses that had been either exercised (n=7) for up to 14 weeks using a standard training regimen for racehorses, or not exercised (n=7). The effect of variation in x-...
Ganiev I, Alexandrova N, Aimaletdinov A, Rutland C, Malanyeva A, Rizvanov A, Zakirova E.One of the major problems observed in veterinary practice is articular cartilage injuries in animals. In terms of agriculture, it leads to their culling from the herd, even if they are highly productive animals. With companion animals, owners usually have to decide between euthanasia or long-term sometimes lifelong treatment of the injury by a veterinarian. The use of mesenchymal stem cells (MSCs) for the treatment of cartilage injury in veterinary medicine is based on the good results observed in preclinical studies, where large animals have been used as experimental models to study the regen...
Lescun TB, Hoffseth K, Yang HT, Hansma PK, Kopeikin HS, Chandrasekar S.To compare results obtained with a handheld reference point indentation instrument for bone material strength index (BMSi) measurements in the equine third metacarpal bone for various testing conditions. Methods: 24 third metacarpal bones. Methods: Third metacarpal bones from both forelimbs of 12 horses were obtained. The dorsal surface of each bone was divided into 6 testing regions. In vivo and ex vivo measurements of BMSi were obtained through the skin and on exposed bone, respectively, to determine effects of each testing condition. Difference plots were used to assess agreement between BM...
Current drug metabolismDecember 19, 2020
Volume 22, Issue 3 215-223 doi: 10.2174/1389200221666201217141025
Hu SX, Ernst K, Benner CP, Feenstra KL.Pharmacokinetic and pharmacodynamic assessment of ester-containing drugs can be impacted by hydrolysis of the drugs in plasma samples post blood collection. The impact is different in the plasma of different species. Objective: This study evaluated the stability of a prodrug, ketoprofen methylester (KME), in commercially purchased and freshly collected plasma of mouse, rat, dog, cat, pig, sheep, cattle and horse. Methods: KME hydrolysis was determined following its incubation in commercially purchased and freshly collected plasma of those species. Different esterase inhibitors were evaluated f...
Fock U, Jockusch BM, Schubert WD, Hinssen H.The actin-binding protein gelsolin is highly conserved in vertebrates and exists in two isoforms, a cytoplasmic and an extracellular variant, generated by alternative splicing. In mammals, these isoforms differ only by an N-terminal extension in plasma gelsolin, a short sequence of up to 25 amino acids. Cells and tissues may contain both variants, as plasma gelsolin is secreted by many cell types. The tertiary structure of equine plasma gelsolin has been elucidated, but without any information on the N-terminal extension. In this paper, we present topographical data on the N-terminal extension...
Sancler-Silva YFR, Silva-Junior ER, Fedorka CE, Scheeren VFC, Cavalero TS, Papa PM, Alvarenga MA, Dell'Aqua JA, Papa FO.The aim of this report is to describe a new methodology to successfully treat stallions diagnosed with urethral rent. Four stallions of ages ranging from 7 to 12 years (median 9) with hemospermia were admitted for clinical evaluation, breeding soundness examination, and urethroscopy for inspection of the urethra and vesicular glands. Once the presence of urethral rent was identified and/or other sources of hemorrhage were excluded, a topical treatment was performed with 4% Policresulen solution (Albocresil). The treatment was carried out by infusing 100 mL of the solution into the lumen of t...