Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Furr MO, Bender H.To determine the effects of age on each analyte, CSF variables were evaluated in healthy foals from birth through 42 days of age. Cerebrospinal fluid was collected from 14 clinically normal, naturally delivered cross-bred foals and was analyzed for glucose, sodium, potassium, magnesium, and total protein concentrations, total and differential WBC counts, RBC count, and lactate dehydrogenase, aspartate transaminase, and creatine kinase activities. Samples were collected in 3 foals < 48 hours old, and at 11 to 14 days of age in 4 foals, 21 to 22 days of age in 3 foals, and 31 to 42 days of ag...
Morais JF, de Freitas MC, Yamaguchi IK, dos Santos MC, da Silva WD.IgG and F(ab')2 fragments were prepared from horse plasma rich in specific antibodies against Brazilian Bothrops or Crotalus venoms. Both preparations, free of gross contamination with non-immunoglobulin proteins, were able to combine in vitro with their respective antigens, forming immune complexes at antigen excess, equivalence or antibody excess, and activating the C system, through either the classical or the alternative pathways. The IgG preparation was more effective in neutralizing the lethal factors in Bothrops or Crotalus venoms, compared with the F(ab')2 fragments. In contrast, IgG a...
Mueller PO, Allen D, Watson E, Hay C.A 2-year-old Standardbred colt was admitted because of lameness of the left hind limb. Physical examination revealed marked effusion of the left femoropatellar and femorotibial joints and grade IV/V lameness of the left hind limb. Radiography of the left stifle revealed a complete fracture of the medial tubercle of the intercondylar eminence of the tibia. Arthroscopy was used to provide diagnostic, therapeutic, and prognostic information. A cranial approach to the medial compartment of the femorotibial joint was performed. Manipulation of the medial tubercle revealed it to be unstable, but a d...
Robert P, Amsellem S, Christophe S, Benifla JL, Bellet D, Koman A, Bidart JM.To investigate the possibility that specific structural determinants within the equine follitropin receptor (eFSHR) are critical to the enhanced specificity of this receptor compared to other FSHRs, we used the RACE-PCR technique to clone the eFSHR from equine testis. Sequence analysis revealed that the eFSHR is highly homologous to other mammal FSHRs, but it presents 10 unique amino acid residue replacements in the extracellular domain. Furthermore, a potential N-glycosylation site was detected at a position not encountered in other receptors. Northern blot analysis identified three transcrip...
Fukunaga Y, Matsumura T, Sugiura T, Wada R, Imagawa H, Kanemaru T, Kamada M.Serum cross neutralisation tests were conducted with a recent American isolate (84KY-A1) and a European isolate, (Wroclaw-2) and compared with the prototype and modified viruses of the Bucyrus strain of equine arteritis virus by using virus specific immune horse sera. The modified Bucyrus strain was neutralised and showed high neutralisation titres with all the immune sera. The prototype Bucyrus strain was also substantially neutralised, followed by the 84KY-A1 strain. As a result of the tests with the modified Bucyrus strain as the antigen, 20 seropositive horses were discovered among home-br...
Cohen ND.A prospective study was conducted to describe the causes of and farm management factors associated with disease and death in a population of foals in Texas. Data from 2,468 foals at 167 farms were provided by veterinarians for all 12 months during 1991. Among 2,468 foals, 116 deaths were reported (4.7%). Pneumonia was the most commonly reported cause of death, followed by septicemia. When considered as a group, musculoskeletal disorders (traumatic, infectious, or deforming problems) represented the most common cause of all reported deaths. Daily risk of death was greatest during the first 7 da...
Holcombe SJ, Bertone AL.A 9-week-old Thoroughbred x Holsteiner colt was referred for evaluation and treatment of lameness of the right hind limb. Radiography of the stifle revealed multiple bony fragments within the lateral portion of the femorotibial joint and a radiolucency of the distolateral portion of the femur in the area of the extensor fossa, which were consistent with avulsion of the origin of the extensor digitorum longus muscle. Arthroscopy of the lateral portion of the femorotibial joint revealed exposed subchondral bone in the area of the extensor fossa, and the origin of the extensor digitorum longus mu...
Sloet van Oldruitenborgh-Oosterbaan MM, van der Velden MA.A review of displacements and surgery of the large colon is given on the basis of two cases. A four-year-old Dutch Warmblood mare was referred, one week before foaling, for colic of twelve hours duration. At rectal palpation a large uterus was found, but no cause for the colic. Laparotomy revealed a colonic volvulus and resection of about 75% of the large colon was necessary. A dead foal was born five days postoperatively, but the mare recovered well. A nine year-old Dutch Warmblood stallion with a history of frequent colic had been treated for nephrosplenic entrapment three times. Resection o...
Beard WL, Bramlage LR, Schneider RK, Embertson RM.Medical records for 64 Thoroughbred and 45 Standardbred horses with osteochondrosis dissecans (OCD) of the tarsocrural joint that were treated by means of arthroscopic removal of the fragments before 2 years of age and before beginning racing were reviewed. Lesion site was recorded for all horses. The other foals from the dams of these surgically treated horses (siblings) were identified from mare progeny records. Racing data, including number of starts and money won during the 2- and 3-year-old racing years were obtained from the Jockey Club and the United States Trotting Association for affe...
Fogarty U, del Piero F, Purnell RE, Mosurski KR.The intestinal tracts of 363 horses were examined after slaughter at a horse abattoir. The presence or absence of Anoplocephala perfoliata and the sites of attachment were recorded. A total of 51 per cent of the horses had A perfoliata attached to the mucosa of the ileocaecal junction and/or to the caecal mucosa; 5 per cent of the horses had A perfoliata attached only to the mucosa of the ileocaecal junction, 24 per cent had A perfoliata attached only to the caecal mucosa and 22 per cent of the horses had A perfoliata attached at both sites. The degree of infestation did not appear to be influ...
Dyson S.Proximal suspensory desmitis of the hindlimb was diagnosed using local analgesic techniques and ultrasonography in 42 horses. Subtarsal analgesia resulted in substantial improvement in lameness in 36 of 41 horses in which local analgesic techniques were used. In the remaining five horses lameness was improved by perineural analgesia of the tibial nerve (three) or the tibial and fibular nerves. Intra-articular analgesia of the tarso-metatarsal joint produced a similar degree of improvement in two of 24 horses in which lameness had been improved by subtarsal analgesia. Ultrasonographic abnormali...
Baker SJ, Gerring EL.The gastric emptying of different forms of ingesta occurs by a variety of mechanisms and dysfunction may selectively affect different components of the gastric contents. A technique for assessing gastric emptying of solid, indigestible, radiopaque markers was developed. Emptying of these markers in four ponies was variable in both pattern and rate (half emptying time ranged from less than one hour to more than 24 hours). However, whereas in man physically similar markers appear to empty relatively rapidly when fasting but are delayed by a meal, no such delay was evident in these ponies. The ho...
Wilson DV, Patterson JS, Stick JA, Provost PJ.The role of platelet-activating factor (PAF) in mediating the colonic damage that develops after large-colon torsion was studied in 14 ponies. Morphologic changes in areas of the ascending colon and selected abdominal and thoracic viscera after 1 hour of large-colon torsion and 3 to 5 hours of reperfusion were determined, as well as the protective effects of systemic administration of a specific PAF antagonist (WEB 2086). Ponies were selected then allocated at random and in equal numbers to 2 groups that received 1 of 2 treatments prior to induction of large-colon torsion: group 1--control (sa...
van Dijk P.The effects of total intravenous anaesthesia with an intravenous infusion of a combination of guaiphenesin, ketamine and detomidine were studied in 10 patients scheduled for elective surgery. Anaesthesia was maintained by the infusion of guaiphenesin (100 mg/ml), ketamine (2 mg/ml) and detomidine (0.02 mg/ml). The infusion rate was 1 ml/kg/hr. During anaesthesia, pulse rate and mean arterial blood pressure were continuously recorded. Arterial blood gases and pH were determined immediately after induction and at stated times during anaesthesia. Venous blood was sampled to determine plasma gluco...
Leigh JA.A protein capable of activating bovine, equine and ovine plasminogen, but not that from human or porcine plasma, was purified from culture filtrates of Streptococcus uberis (strain 0140J). Purification was achieved by ammonium sulphate precipitation followed by molecular exclusion chromatography. The elution position of the native molecule was equivalent to a molecular mass of approximately 57 kDa. However, the molecular mass, as determined by SDS-PAGE, was 29 kDa, suggesting the existence of a dimeric structure. Purified immunoglobulin from three out of five monoclonal antibodies raised to th...
Baptiste KE, Cake MH.The guttural pouch is a large, air-filled diverticulum of the auditory tube, present in the horse and other species. Lipid analysis of saline lavage from the equine guttural pouch has demonstrated the presence of phospholipids and neutral lipids in amounts that are variable but consistently greater than in any other species described. A stain specific for choline-containing phospholipids has demonstrated the presence of phospholipid-containing vesicles only within the cells of subepithelial, seromucoidlike glands, suggesting that these cells incorporate phospholipids in their secretions. The f...
Kihurani DO, Nantulya VM, Mbiuki SM, Mogoa E, Nguhiu-Mwangi J, Mbithi PM.Equines are particularly susceptible to infection with Trypanosoma evansi and T. brucei, but rarely is natural T. congolense and T. vivax infection seen in horses. An outbreak of trypanosomosis occurred in a herd of horses used for patrolling the pineapple fields on the Del Monte Farm, Thika, Kenya initially involving 6 horses. On subsequent screening of the entire group, T. brucei, T. congolense and T. vivax infections were detected in 16 of the 35 horses. The tests used for diagnosis included microscopic examination of stained blood smears, buffy coat technique, mouse inoculation and antigen...
Prieto D, Simonsen U, Martín J, Hernández M, Rivera L, Lema L, García P, García-Sacristán A.The distribution of acetylcholinesterase (AChE)-positive nerve fibers and cells, as well as the effects of acetylcholine (ACh) on ureteral smooth muscle and small resistance arteries were investigated in the equine ureter by means of histochemical, classic organ baths and myograph techniques. AChE-positive nerve fibers were widely distributed throughout the ureteral wall forming muscular, subepithelial and perivascular nerve plexuses, whose density was highest at the intravesical ureter. AChE-positive nerve cells were also identified grouped as adventitial or intramural ganglia. ACh increased ...
Sertich PL, Reef VB, Oristaglio-Turner RM, Habecker PL, Maxson AD.A multiparous pregnant Welsh Pony mare was examined because of anorexia, dyspnea, and a large abdomen. Ultrasonography of the uterus revealed an excessive amount of amniotic fluid surrounding the fetus. Transabdominal ultrasonography permitted differentiation of hydrops amnii from hydrops allantois. The mare aborted a 7-month-old fetus with brachygnathia and a large, edematous umbilical cord. Hydrops amnii, an excessive accumulation of amniotic fluid in the amniotic cavity, is most commonly reported in cattle and sheep.
Turner AS.Congenital and acquired torsion occur in the limbs of domestic animals. Congenital abnormalities are of clinical significance in foals; they are also seen in calves whose dams have ingested certain toxic plants that contain teratogenic agents. Acquired torsional deformities are most common in foals, but are also observed in adult horses, dogs, and llamas. Acquired rotational deformities are almost always associated with angular limb deformities. The clinical consequence of torsional deformities is the early development of degenerative joint disease.
Connally BA, Derksen FJ.The usefulness of tidal breathing flow-volume loops (TBFVL) to evaluate pulmonary function was investigated in 6 Standardbreds during treadmill exercise. Tidal breathing flow-volume loops are a graphic representation of airflow rate vs tidal volume for each individual breath. These TBFVL were obtained from horses exercising at speeds corresponding to 75 and 100% of maximum heart rate. Measurements were recorded in each horse before and after ovalbumin-induced allergic lung disease. Moderate obstructive lung disease, characterized by a significant increase in pulmonary resistance, was observed ...
Sakamoto T, Fawcett JA, Innan H.Horses have substantial variation in coat color, and the genetic loci responsible for the coat color variations have been well investigated. It has been believed that some color variations should follow a single-locus Mendelian law. Examples include the Gray locus that causes the gray phenotype and the Extension locus that specifies the chestnut phenotype. We reevaluated the roles of the Gray and Extension loci by using a large number of mating records of Thoroughbred racing horses. We showed that the data indeed fits the Mendelian law extremely well for the two loci. Furthermore, we demonstra...
Wang ZW, Yu MF, Robinson NE.Muscarinic autoreceptors on horse airway cholinergic nerves were studied by examining the effects of muscarinic receptor antagonists on electrical field stimulation (EFS)-induced acetylcholine (ACh) release in trachealis preparations. All the antagonists including atropine (non-selective), pirenzepine (M1-selective), AF-DX 116 (M2-selective), and hexahydrosiladifenidol (M3-selective) augmented ACh release concentration-dependently. The augmentation was not due to displacement of ACh molecules from tissue receptors into the bath liquid because incubation with atropine after EFS had no influence...
Zibura AE, Cullen MA, Rutledge H, Lassalle L, Salmon JH, Gilger BC, Westermeyer HD.Determine optimal iontophoresis times for riboflavin delivery to the corneal stroma across different species and compare these to corneal injection. Methods: Ex vivo horse, dog, rabbit, and pig globes were treated with riboflavin administered with either iontophoresis for 2.5-20 minutes with or without corneal epithelium; or with purpose-designed precise corneal injection (PCI) application with intact epithelium. Immediately following riboflavin administration, samples were harvested, frozen, and sectioned. Riboflavin penetration was imaged using fluorescence microscopy. Results: Horse sample...
Goudet G, Bézard J, Belin F, Duchamp G, Palmer E, Gérard N.The in vitro maturation rate of equine oocytes remains low, regardless of culture conditions. Our objective was to determine the reasons for failure of equine oocytes to resume meiosis during in vitro maturation and to ascertain the influence of the estrous cycle stage on meiotic competence. In 10 cyclic mares, 7 ultrasound-guided follicular punctures were performed alternately during the follicular phase (group DF; n = 3 punctures), at the end of the follicular phase (group EF; n = 2), and during the luteal phase (group DL; n = 2). We evaluated the competence of the oocytes for in vitro matur...
Cox JE.The false rig is a castrated horse which shows masculine behaviour of one sort or another. The behaviour patterns reported to the author by owners of such animals and the possible causes are discussed here. Some such horses can show all the behaviour patterns of the entire, including erection and intromission. Evidence is presented that the behaviour is not hormonally induced or hormone dependent. The thesis is put forward that the behaviour shown is part of the normal social interaction between horses and possible treatments are discussed in the light of this possibility.
Milillo P, Traversa D, Elia G, Otranto D.Larvae of Rhinoestrus spp. (Diptera, Oestridae) infect nasal and sinus cavities of horses, causing a nasal myiasis characterized by severe respiratory distress. Presently, the diagnosis of horse nasal botfly relies on the observation of clinical signs, on the post mortem retrieval of larvae or on molecular assays performed using pharyngeal swabs. The present study was carried out to characterize larval somatic proteins and salivary glands of Rhinoestrus spp. in a preliminary assessment towards the immunodiagnosis of equine rhinoestrosis. Out of the 212 necropsied horses 13 were positive for th...
Card CE, Manning ST.Fetal maturation and equine parturition are not understood fully, although the adrenal and thyroid glands are thought to have regulatory roles. Thyroidectomized equine fetuses undergo prolonged gestation, and spontaneous diseases such as thyroid musculoskeletal disease and gestational fescue endophyte exposure are also associated with delayed parturition. Thyroid musculoskeletal disease is characterized by: histologically hyperplastic thyroid glands, chondro-osseous dysplasia and dysgenesis, angular limb deformity, low resting thyroxine and triiodothyronine concentrations, and lack of response...
Petrova V, Yonkova P, Simeonova G, Vachkova E.Subcutaneous fat tissue is an accessible and abundant source of multipotent stem cells for cell therapy in regenerative medicine. Successful trilineage differentiation is required to define the stemness features of the obtained mesenchymal cells, and adipogenesis is a part of it. Since indomethacin is bound to serum albumin, replacing foetal bovine serum (FBS) with horse serum (HS) in adipogenic induction protocols would suppress its cytotoxic effect and reveal a better adipogenic potential in equine MSCs. The equine subcutaneous adipose-derived stem cells (ASCs) were separately induced in adi...
Minervino AHH, Andersson E, Norlander E, Moreira TR, Gennari SM, Mercado Caruso N, Moraes Filho J, Marcili A, Martins TF, Labruna MB.From a previous large epidemiological survey, we randomly selected 474 serum samples (463 horses and 11 mules) distributed among four municipalities of Pará state, Amazon region, Brazil, and from three types: farm animal, urban carthorse, and sport horse. Samples were tested by indirect fluorescence antibody test (IFAT ≥ 64) for antibodies reactive to spotted fever group (SFG) rickettsiae using Rickettsia rickettsii as crude antigens. From the 474 equids tested, 149 (31.4%) had ticks attached during sampling, belonging mostly to the species Dermacentor nitens. The overall seroprevalence...
Wagner PC, Shires GM, Watrous BJ, Kaneps AJ, Schmotzer WB, Riebold TW.Fifteen horses with flexural deformity of the metacarpophalangeal joint were evaluated and their conditions were designated as mild, moderate, or severe. Evaluations were made on the basis of clinical signs and lesions seen on radiography. Horses with mild deformities were treated with corrective trimming and shoeing; those with moderate deformities were treated with desmotomy of the accessory ligament of the deep digital flexor tendon and corrective shoeing. Desmotomies of the accessory ligaments of both deep and superficial digital flexor tendons were performed on horses severely affected, f...
Norman T, Chaffin K, Schmitz D.The equine small intestine is challenging to evaluate ultrasonographically. In humans, hydrosonography has been used to improve ultrasonographic images of the small intestine. We hypothesized that fasting horses for 24 h would enhance the ability to image the small intestine transabdominally by separating intestinal loops and reducing intraluminal gas, and that the administration of intragastric contrast agent would further improve that ability. Ten healthy horses were examined ultrasonographically under three treatment conditions: (a) regular diet, (b) after a 24-h fast, and (c) fasted plus i...
Martens RJ, Cohen ND, Chaffin MK, Waskom JS.To quantify and compare geochemical factors in surface soils from horse-breeding farms with horses with pneumonia caused by Rhodococcus equi (affected farms) and horse-breeding farms with no history of pneumonia caused by R equi (unaffected farms). Methods: Soil from 24 R equi-affected farms and 21 unaffected farms. Methods: Equine veterinary practitioners throughout Texas submitted surface soil samples from areas most frequented by foals, on R equi-affected and unaffected horse-breeding farms in their practice. Soil samples were assayed for the following factors: pH, salinity, nitrate, phosph...
Winfield LS, Brooks MB.A 23-year-old Thoroughbred mare was evaluated because of a coagulopathy causing hemoperitoneum, hematomas, and signs of blood loss-induced anemia. Results: The mare had tachycardia, pallor, hypoperfusion, and a large mass in the right flank. The mass was further characterized ultrasonographically as an extensive hematoma in the body wall with associated hemoabdomen. Coagulation testing revealed persistent, specific prolongation of the activated partial thromboplastin time (> 100 seconds; reference interval, 24 to 44 seconds) attributable to severe factor VIII deficiency (12%; reference inte...
Stevenson AJ, Weber MP, Todi F, Young L, Beaumier P, Kacew S.Plasma and urinary concentrations of procaine were examined in Standardbred mares after subcutaneous administration of various doses (80 mg to 1600 mg) of procaine hydrochloride. Regardless of dose, peak plasma procaine values occurred within 1 h, but remained detectable in a dose-dependent manner, with procaine present at 1 h with the 80 mg dose and 6 h at the 1600 mg dose. Similarly, peak urinary procaine concentrations were attained within 1.5 to 3 h, irrespective of dose, while detection time was dose-dependent, being 23 h for 80-200 mg doses but as long as 30-54 h with the 1600 mg dose. W...
Engeli E, Yeager AE, Erb HN, Haussler KK.The purpose of this study was to establish the normal percutaneous ultrasonographic appearance of anatomic structures within the equine sacroiliac region. Percutaneous ultrasonography was performed in a cranial-to-caudal direction in 10 normal adult live horses. The following structures were examined in detail: supraspinous ligament, lumbar and sacral spinous processes, thoracolumbar fascia and its caudal extension, tubera sacralia, ilial wings, dorsal and lateral portions of the dorsal sacroiliac ligaments, lateral part of the sacrum, and the lateral sacral crest. After ultrasonography, all a...
van den Wollenberg L, Pellicaan CH, Müller K.Two horses were accidentally administered propylene glycol instead of mineral oil. After discovery of the mistake intensive medical therapy with intravenous fluids, etc. was started, and both animals recovered fully from their clinical symptoms. Veterinarians use propylene glycol as well as paraffin routinely for the treatment of their patients. Mistakes are likely to be made because both medicines and sometimes their packing have a similar appearance. Several incidents have been reported in other countries. A large amount of propylene glycol given to a horse, but also to other animals, can be...
MacLeay JM, Wilson JH.A 14-year-old Arabian mare was admitted for lethargy, anorexia, and low fecal output. On the basis of laboratory, physical examination, and electrocardiographic findings, diagnoses of type-II renal tubular acidosis (RTA), impaction of the large colon, and ventricular tachycardia were made. Diagnosis of type-II RTA was based on measurement of a low fractional excretion value for potassium and fractional excretion value for sodium within the reference range. In contrast, horses with type-I RTA have high fractional excretion values for sodium and fractional excretion values for potassium within r...
Hoffman AM.Respiratory diagnostic instruments previously available only to referral centers should be converted into miniature, portable, wireless medical devices for use in practice. Internet and wireless connections of these instruments should expedite the process of seeking second opinions and in general information sharing. We are moving into a world of greater objectivity that should free us from speculation in some areas, yet open new avenues for research and innovation in others.
Button C, Gross DR, Johnston JT, Yakatan GJ.The pharmacokinetics of IV administered digoxin and the bioavailability of intragastrically administered powdered digoxin tables suspended in water were investigated in 6 clinically normal adult horses by 125I radioimmunoassay. The effect of 3 to 5 sequential IV doses of 5 micrograms of digoxin/kg of body weight at 2-hour intervals on a left ventricular index of contractility (Vmax) was assessed in 5 clinically normal horses. Standard pharmacokinetic equations and mean pharmacokinetic variables were used to derive parenteral and oral (loading and maintenance) doses for digoxin in horses. The c...
Jellyman JK, Allen VL, Holdstock NB, Fowden AL.Studies in humans and animals have linked abnormal programming of adult tissue function to excess glucocorticoids during perinatal development. The current study investigated the hypothesis that physiological variations in glucocorticoid concentrations during early neonatal life of the foal alter the secretory responses of the pancreatic β cells 2 and 12 wk after treatment. Spontaneously delivered foals received either saline or long-acting ACTH for 5 d from 1 d after birth to maintain an endogenous rise in cortisol concentrations. Starting at d 10, pancreatic β cell function was studied usi...
