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.
Linford RL.Quantitated locomotion analysis is increasingly being used during assessment and treatment of gait disorders in human beings. Locomotion analysis is also thought to have potential for enhancing the assessment of lameness in horses. Availability of high-speed video recording systems has simplified the process of quantitated locomotion analysis; however, the high cost of such systems has limited their use for routine clinical assessment in horses. The temporal resolution of 500- to 1,000-images/s (Hz) recording systems is beyond what has been considered necessary for precise quantitation of shor...
Kawcak CE, McIlwraith CW.The results of arthroscopic surgery in the treatment of osteochondral fragmentation of the proximodorsal aspect of the first phalanx and the influence of other fetlock joint lesions on prognosis were evaluated in 336 horses. Horses were classified as: 1) returning to previous use at the same or higher class of performance; 2) returning to previous use (regardless of class of performance); or 3) failing to return to previous use. Ninety-six horses (29%) had fragmentation alone; 140 horses (42%) had fragmentation and additional fetlock lesions, and 100 horses (29%) underwent concurrent carpal ar...
McCarthy PH.A description is given of 75 features present in the normal tarsus of the standing horse which are apparent due to visible skin contours overlying them. Depending on whether or not the pelvic limb is supporting full weight or resting, some contours alter their configuration. Therefore the contour of each underlying feature is described separately for each stance of the limb. It is considered that visual inspection and identification of the apparent superficial features of the normal equine tarsus form the basis of orientation and clinical inspection. Furthermore, these features provide referen...
Silver M, Fowden AL.The present study was carried out on 19 chronically catheterized mares and fetuses in late gestation (term > 320 days). In six animals which were monitored up to the time of delivery of a live foal, plasma and amniotic fluid cortisol concentrations remained low until 4-5 days before parturition when there was a rapid, significant rise (P < 0.05) which was not accompanied by any corresponding changes in maternal plasma cortisol. Circulating fetal ACTH concentrations became more variable close to delivery and ANOVA revealed no significant increases during this critical period, although a n...
Maisi P, Koivunen AL, Rantala AR, Turgut K.The health of the respiratory tracts of 19 horses was studied for 11 months. The horses were placed into 3 groups (healthy, periodically diseased and continuously diseased) based on the measurements of blood gases, intrapleural pressure and on neutrophil content of tracheal mucus. Lysosomal enzymes (N-acetyl-beta-D-glucosaminidase and beta-glucuronidase) and reflectors of the proteolytic system (plasmin, plasminogen, trypsin inhibitor capacity) were determined. beta-glucuronidase appeared to be a good indicator of the presence of disease of the respiratory system. High beta-glucuronidase value...
Lumsden JM, Stick JA, Caron JP, Nickels FA.Medical records of 51 horses with epiglottic entrapment were reviewed, and the outcome after surgical treatment was evaluated by use of results from a survey of owners and from race records. Horses with epiglottic entrapment and no additional problem (uncomplicated) of the nares, nasal passages, pharynx, or larynx (upper airway) that were treated by transoral axial division (group 1) or resection via laryngotomy (group 2), and horses with epiglottic entrapment complicated by an additional upper airway abnormality (group 3) were compared. The cost of treatment, duration of hospitalization, time...
Golenz MR, Wilson WD, Carlson GP, Craychee TJ, Mihalyi JE, Knox L.The suitability of the intraosseous (i.o.) route for drug administration to equine neonates was evaluated in a study comparing the pharmacokinetics of amikacin administered by the i.o. and intravenous (i.v.) routes. Using a cross-over study design amikacin sulphate (7 mg/kg bwt) was administered i.o. or i.v. to 6 healthy foals at 3 and 5 days of age. Amikacin was instantaneously and completely absorbed after i.o. administration, achieving a mean +/- sd peak concentration (34.17 +/- 3.54 micrograms/ml) in the first sample collected 3 min after administration which was not significantly differen...
Sato H, Matsumori Y, Tanabe T, Saito H, Shimizu A, Kawano J.A new type of staphylococcal exfoliative toxin (sET) was isolated from the culture filtrate of a Staphylococcus aureus strain isolated from a horse with skin infection including phlegmon. The new sET was purified by precipitation with 80% saturated ammonium sulfate, column chromatography on DEAE-cellulofine A-500, gel filtration on a Sephadex G-75 column, and polyacrylamide gel electrophoresis (7.5% polyacrylamide). The new sET elicited general exfoliation of the epidermis with the so-called Nikolsky sign when inoculated into both 3-day-old mice and 1-day-old chicks, whereas sETA and sETB from...
Vail TB, Trotter GW, Powers BE.The osteoinductive capability of four particle sizes of equine demineralized bone matrix (DBM) was evaluated. Matrix particles were implanted in brachiocephalicus muscle pouches in six horses and were harvested 8 weeks later. Matrix particle sizes of 2.0 mm3 to 4.0 mm3 and 5.0 mm3 to 10.0 mm3 were associated with osteoinductive activity and minimal signs of local inflammation. The two smaller particle sizes (0.425 mm3 to 0.850 mm3 and 0.850 mm3 to 2.0 mm3) were minimally osteoinductive and were associated with a greater local inflammatory response. Microscopic events associated with new bone p...
McClure SR, Watkins JP, Bronson DG, Ashman RB.Axial stability of equine oblique proximal phalangeal osteotomies with application of the standard short limb cast or 1 of 3 configurations of transfixation casts was determined in vitro. Transfixation cast methods included use of parallel pins, divergent pins, or parallel pins incorporating a metal walking bar. Displacement at the osteotomy was recorded for each limb at 4,448 N. Standard short limb casts provided significantly (P = 0.0002) less axial stability than did any form of transfixation cast. Significant differences were not found between the 3 transfixation casts.
Zhou J, Spier SJ, Beech J, Hoffman EP.It is often suggested that polygenic or environmental factors are responsible for clinical variability between patients with identical mutations. However, most dominant diseases are caused by a change-of-function alteration in the mutant allele's protein product. All patients are heterozygous and presumably express both mutant and normal proteins from the corresponding genes. Thus, a possible molecular mechanism for clinical variability could be the difference in relative levels of mutant vs. normal mRNA in different patients with the same mutation. To investigate this hypothesis, it is necess...
Biswas B, Vemulapalli R, Dutta SK.Potomac horse fever, caused by Ehrlichia risticii, is an important disease of equines. The major features of the disease are fever, leukopenia, and diarrhea. The organism has been detected from the blood mononuclear cells of infected horses, but its presence in the feces has not been known. A method for immunomagnetic separation of E. risticii from the feces of infected horses was developed, and the separated organisms were detected by PCR. Coating immunomagnetic beads (Dynabeads) with a 1:5 dilution of rabbit anti-E. risticii serum and incubating the Dynabeads with fecal samples for 25 min at...
Amselgruber WM, Sinowatz F, Erhard M.The present study deals with the immunohistochemical localization of S-100 protein in the testes of seven mammalian species including rat, cat, dog, pig, sheep, cattle and horse. Significant differences are demonstrated in the cellular distribution and intensity of immunoreaction for the protein. In bull, ram, boar and cat testes S-100 protein was localized in the cytoplasm and nuclei of Sertoli cells. A particularly intense staining was seen in the modified Sertoli cells of the terminal tubular segment. With the exception of the cat and horse S-100 protein immunoreactivity was additionally fo...
Moens Y, Lagerweij E, Gootjes P, Poortman J.Effects of differential ventilation on gas exchange were studied in 7 isoflurane-anesthetized, laterally recumbent horses, and were compared with effects of conventional ventilation, using similar minute volume. A tracheal tube-in-tube intubation technique allowed each lung to be connected separately to an anesthetic circle system with a ventilator. Two distribution patterns of tidal volume were investigated; half the tidal volume was distributed to each lung and two-thirds the tidal volume was distributed to the dependent lung. Effects of the combination of these patterns with positive end-ex...
Smith BL, Jones JH, Carlson GP, Pascoe JR.It has been hypothesised that horses have a preference for facing backward in a trailer during road transport in order to minimise shifts of body weight due to accelerations and decelerations. To determine if horses have preferences for facing forward vs. backward in a horse trailer, the authors analysed the percentages of time horses spent in different body positions and directions while standing in a moving or parked horse trailer. Body positions and directions of 8 Thoroughbred geldings were videotaped while horses were transported singly and untethered in a 4-horse stock trailer over a 32 ...
Milne EM, Pemberton AD, McGorum BC, Dixon PM, Scudamore CL, Miller HR.The concentration of alpha-1 proteinase inhibitor (API) was measured in the pulmonary epithelial lining fluid (PELF) of horses with chronic obstructive pulmonary disease (COPD) while they had clinical signs and while they had none. The concentrations of total protein, albumin and API were significantly higher in the PELF of animals with clinical signs of COPD. The correlation between albumin and API in the PELF suggested that most of the API was derived from the serum.
Lavoie JP, Fiset L, Laverty S.A retrospective study of 40 horses with primary lung abscesses without pleuropneumonia showed that lung abscesses occurred predominantly in young horses, usually in foals aged < or = 6 months. Hyperfibrinogenaemia was present in all but 2 horses, and other common clinical and haematological findings were hyperthermia, tachycardia, polypnoea, and neutrophilic leucocytosis. The most common bacterial species isolated from transtracheal aspirates were Streptococcus zooepidemicus (20/34) and Rhodococcus equi (13/34). Most horses (23/27) discharged from the hospital were long term survivors. Of t...
Pollitt CC.In the equine hoof, the basement membrane connects the heavily keratinised hoof wall to the dense connective tissue of the distal phalanx, a region able to withstand considerable mechanical stress. This study investigated the properties of this important anatomical and physiological structure. In contrast to haematoxylin and eosin, the connective tissue stains, periodic acid Schiff, periodic acid silver methenamine and Azan showed good resolution of lamellar basement membrane. The lamellar basement membrane cross-reacted with mouse monoclonal antibodies raised against human laminin, thereby pr...
Deregt D, de Vries AA, Raamsman MJ, Elmgren LD, Rottier PJ.Monoclonal antibodies (MAbs) to equine arteritis virus (EAV) proteins were produced and characterized. The protein specificities of eight MAbs were determined definitively by immunoprecipitation of EAV proteins expressed from vaccinia virus recombinants (VVRs). Included were two new VVRs produced for this study, expressing the M and the GL proteins, respectively. Three MAbs were determined to be N-specific and five MAbs recognized the GL protein. One GL-specific MAb, 17F5, of the IgA class, efficiently neutralized EAV infectivity. In competitive binding assays (CBAs), the N-specific MAbs defin...
Newton-Clarke MJ, Guffoy MR, Dykes NL, Divers TJ.A haemangiosarcoma in a horse resulted in ataxia affecting all four legs, a low head carriage and a reluctance to flex the neck. Ancillary diagnostic procedures included the analysis of cerebrospinal fluid, standing lateral cervical radiographs and a myelogram. Post mortem a tumour was found which involved the body of the second cervical vertebra and the associated hypaxial muscles, with secondary intravertebral extradural infiltration and focal compressive myelopathy. A histological examination showed that the tumour was a haemangiosarcoma.
Verma RD, Venkateswaran KS, Sharma JK, Agarwal GS.Malleo-proteins from synthetic broth mallein of six strains of Pseudomonas mallei were separated by trichloroacetic acid precipitation, ammonium sulfate precipitation and Ultrogel AcA 34 gel filtration chromatography. When tested comparatively with Dutch PPD mallein as standard on P. mallei-sensitized and normal horses all the strains were found to be malleinogenic, trichloroacetic acid precipitated proteins were comparable to Dutch PPD mallein in potency and innocuity whereas ammonium sulfate-precipitated proteins elicited non-specific reactions. Ultrogel AcA 34 chromatographed high molecular...
Yarbrough TB, Langer DL, Snyder JR, Gardner IA, O'Brien TR.Medical records of 245 horses that had been evaluated by use of abdominal radiography between January 1990 and December 1992 were reviewed. One hundred forty-one horses subsequently had a postmortem examination or surgical exploration performed for definitive lesion diagnosis. The signalment, diagnosis, site, and number of enteroliths were obtained from the medical records. Radiographs were evaluated individually by 3 reviewers for the presence of enteroliths, preferred diagnostic view, evidence of large colon tympany, and film quality. Of the 141 cases reviewed, 66.7% (94/141) had confirmed e...
Troyer D, Howard D, Leipold HW, Smith JE.Southern blot analysis of equine DNA's digested with the restriction endonuclease Hinfl hybridized with a 32 PdCTP labeled human VNTR probe revealed a highly polymorphic pattern of restriction fragments upon autoradiography. The horses were unrelated individuals of the quarter horse breed. This heterologous probe can thus be used in the equine species for individual identification and pedigree analysis.
Han X, Fowden AL, Silver M, Holdstock N, McGladdery AJ, Ousey JC, Allen WR, Rossdale PD, Challis JR.An increase in fetal adrenal cortisol output signals the onset of parturition in many animal species but, in the fetal horse, plasma concentrations of cortisol remain low for much of late pregnancy, with a rise occurring only very close to the time of birth (term 320-360 days). Immunohistochemistry was used to determine the localisation and changes in distribution of key steroidogenic enzymes for cortisol production; P450scc, P450C17 and 3 beta-hydroxysteroid dehydrogenase (3 beta HSD) in adrenal tissue from fetal and newborn horses and these findings were correlated with the appearance of imm...
Gräfner G, Zimmermann H, Karge E, Münch J, Ribbeck R, Hiepe T.Systematic faunal studies in the district Schwerin showed at the present time there are 3 more or less damage-biotopes existing in the districts of Perleberg, Ludwigslust and Parchim; 5 river sources can be considered as potential sources, 5 are temporary and 2 are ephemeral whilst in 3 further areas environmental influences such as effluent impairs the flow of the river and the developmental stages of Simuliidae were not observed.--The following species were found: Boophthora erythrocephala, Wilhelmia salopiensis, Wilhelmia equina, Odagmia ornata, Eusimulium aureum and Eusimulium lundstroemi....
Ginther OJ, Bergfelt DR.The temporal associations between increases in FSH and growth of small follicles (2-20 mm) were studied during one oestrous cycle (ovulation to ovulation) in 15 horse mares. Follicular diameters were obtained ultrasonically. For each day, follicles were combined for both ovaries, grouped from largest to smallest (excluding dominant follicles), and divided into three to five tiers of six follicles for each mare (for example: tier 1, six largest follicles; tier 2, next six largest follicles). A significant increase in mean diameters followed by a significant decrease was used to define a follicu...
Evans JW, Hughes JP, Neely DP, Stabenfeldt GH, Winger CM.Jugular blood samples were obtained from 8 mares at 5- and/or 20-min intervals for 2 to 5 days during various phases of the oestrous cycle for plasma LH determination. An episodic release pattern was observed in 1 of 3 mares sampled during the ovulatory period. One mare had one secretory burst and the other mare had several periods of fluctuating plasma LH concentration. During dioestrus, episodic secretions were observed in 2 mares sampled 11 to 13 days before and, in 1 mare, 9 days after ovulation. During the 2 to 5-day period before ovulation, episodic secretion was not observed (3 mares) b...
Lloyd D, Johanson C, Phillips TJ.Minimally displaced condylar fractures propagating into the third metatarsal diaphysis were treated conservatively in one thoroughbred and two Arabian racehorses. In each case a neuroleptanalgesic protocol provided adequate pain relief for a rigid fibreglass cast to be applied in a weight-bearing position. The fractures healed completely and the three horses recovered uneventfully. Two of them returned successfully to racing and the third was used for breeding.
Salciccia A, Sandersen C, Grulke S, de la Rebière de Pouyade G, Caudron I, Serteyn D, Detilleux J.The objectives of this study were to describe and relate perioperative changes in blood leukocyte counts to the outcome of surgical colic horses, determine a cut-off value in the early postoperative period to obtain an indicator of the outcome, and compare the obtained value to a validation population of horses. Fifty-three horses undergoing colic surgery were included in the descriptive part of the study. Total leukocyte counts were performed before, during and serially after surgery. A receiver operating characteristic analysis was performed on the leukocyte counts of 45 of these horses to d...
Davies HM, Merritt JS.Bone strains quantify skeletal effects of specific exercise and hence assist in designing training programmes to avoid bone injury. Objective: To test whether compressive strains increase on the lateral surface of the inside third metacarpal bone (McIII) and the medial surface of the outside McIII in a turn. Methods: Rosette strain gauges on dorsal, medial and lateral surfaces of the midshaft of the left McIII in 2 Thoroughbred geldings were recorded simultaneously during turning at the walk on a bitumen surface. Results: Medial surface: Compression peaks were larger in the outside limb. Tensi...
Clulow JR, Buss H, Evans G, Sieme H, Rath D, Morris LH, Maxwell WM.Sex-sorted, frozen-thawed stallion spermatozoa remain out of reach of commercial horse breeders because of the low efficiency of the sex-sorting process and unacceptable fertility rates after insemination. Two experiments were designed to test the effects of alternative staining and freezing media to improve the viability of sex-sorted frozen-thawed stallion spermatozoa. Experiment 1 compared two freezing media, INRA 82(®) and a modified lactose-ethylenediaminetetraacetic acid (EDTA), for the cryopreservation of sex-sorted stallion spermatozoa. No significant differences between the two freez...
Schorr G.Serum iron concentration and iron-binding capacity were determined in 34 respectively 35 clinically healthy horses of different sex, with the age of 3 to 21 years. In the Warm blooded horse, the Half bred, the Haflinger horse, the Heavy horse and the Arabian Haflinger the mean serum iron concentration amounted to 253 +/- 66 micrograms/dl, 202 +/- 87 micrograms/dl, 166 +/- 67 micrograms/dl, 183 micrograms/dl and 366 micrograms/dl, while the iron-binding capacity in the Warm blooded horse, the Half bred, the Haflinger horse, the Thoroughbred, the Heavy horse and the Arabian Haflinger ran up to 4...
Hurtig MB, Farrow CS, Fretz PB.The radial carpal and intermediate carpal bones were found to be fused in a four year old Quarterhorse stallion having a subtle forelimb lameness. Clinical examination, diagnostic local anesthesia, radiography and arthroscopy were used to arrive at the diagnosis. A cause could not be established, although perinatal deformation of cartilagenous carpal bone templates is suspected. A similar case of carpal bone fusion was found among carpi collected for an anatomical study, indicating this condition may be more common than expected. Clinicians should carefully evaluate the flexed lateral view of ...
Onder Z, Yildirim A, Duzlu O, Ciloglu A, Yetismis G, Karabulut F, Inci A.This study was conducted to determine single nucleotide polymorphisms (SNPs) and the benzimidazole (BZ) resistance in strongyle nematode egg populations in horses using molecular techniques. A total of 200 fecal samples were collected from horses in 26 farms in two provinces (Kayseri and Nevşehir) of the Central Anatolia Region of Türkiye between May and August 2022. The flotation method was used to detect strongyle nematode eggs in the fecal samples of the horses. Afterward, strongyle nematode eggs were collected, and the allele-specific polymerase chain reaction (AS-PCR) technique was used...
Jackson M, Geyer H, Fürst A.This study concerns the vestigial metacarpal and metatarsal bones, so called splint bones. The soft tissues, which stabilize the splint bones were carefully examined. The palmar metacarpal/plantar metatarsal fascia, the metacarpal/metatarsal interosseous ligaments and the fibres, which exit distally from the splint bone, were examined in depth. Cadaveric distal limbs were collected from 5 slaughtered or euthanized horses. The legs were examined both, microscopically and macroscopically. The palmar metacarpal/plantar metatarsal fascia is a very stable structure, which connects the splint bone w...
Da Silva-Álvarez E, Gómez-Arrones V, Martín-Cano FE, Gaitskell-Phillips G, Ortiz-Rodríguez JM, Carrasco JJ, Gil MC, Peña Vega FJ....In this study, uterine blood flow area (BFA) has been evaluated for the first time using power Doppler ultrasound (PD) as a marker of endometritis in mares and jennies. The uterine BFA in healthy mares was greater in oestrus than in diestrus (p < .001). However, differences in endometrial blood flow between oestrus and diestrus were not observed in mares with endometritis. The uterine blood flow in healthy jennies is not affected by the oestrus cycle. Both species showed an increase in endometrial BFA in pathological uterine conditions compared to controls. BFA was a good marker of endome...
Piccinelli C, Jago R, Milne E.Equine dysautonomia (grass sickness) is characterized by autonomic neuronal degeneration and is often fatal. As outbreaks occur, rapid diagnosis is essential but confirmation currently requires histological examination. This study evaluated diagnostic accuracy of cytological examination of cranial cervical ganglion (CCG) scrapings for dysautonomia diagnosis. CCG smears from 20 controls and 16 dysautonomia cases were stained with May-Grünwald Giemsa (MGG), hematoxylin and eosin (HE), and cresyl fast violet (CFV), with HE-stained histological sections of CCG as gold standard for diagnosis. Exam...
Scotty NC, Evans TJ, Giuliano E, Johnson PJ, Rottinghaus GE, Fothergill AW, Cutler TJ.Lufenuron is a benzoylphenyl urea-derived insecticide that has been recently introduced as a novel treatment for fungal infections in horses. The purposes of this study were to determine (1) the in vitro efficacy of lufenuron against Aspergillus and Fusarium spp. and (2) the ability of lufenuron to reach efficacious blood concentrations after PO administration in horses. Fungal colonies isolated from diseased equine corneas were tested against lufenuron solutions up to 700 microg/mL. Twenty-one adult horses received 1 of 3 PO lufenuron treatment regimens: 5 mg/kg body weight (BW) q24h for 3 da...
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.
Frias AF, Mársico F, Gómez de Segura IA, Nascimento PR, Nascimento A, Soares JH, Almosny NR.To characterize responses to different doses of propofol in horses pre-medicated with xylazine. Methods: Six adult horses (five females and one male). Methods: Each horse was anaesthetized four times with either ketamine or propofol in random order at 1-week intervals. Horses were pre-medicated with xylazine (1.1 mg kg-1 IV over a minute), and 5 minutes later anaesthesia was induced with either ketamine (2.2 mg kg-1 IV) or propofol (1, 2 and 4 mg kg-1 IV; low, medium and high doses, respectively). Data were collected continuously (electrocardiogram) or after xylazine administration and at 5, 1...
Paulino PG, Peckle M, Mendonça LP, Massard CL, Antunes S, Couto J, Domingos A, Guedes Junior DDS, Cabezas-Cruz A, Santos HA. is the only tick species known to serve as a biological vector of for horses and other equids in Brazil. The protozoan is one of the causal agents of equine piroplasmosis, a major threat in horse breeding systems. Vector competence is closely linked to the pathogens' ability to evade tick defense mechanisms. However, knowledge of tick immune response against infections by hemoparasites of the genus is scarce. In the present study, the expression of genes involved in immune signaling pathways of adults' guts when challenged with a high or low parasitic load of was evaluated. This research...
Nunamaker DM, Richardson DW, Butterweck DM.Plate luting, a technique that uses polymethylmethacrylate (PMMA) interposed between the plate and the bone, as well as between the screw heads and the plate, to improve the stability of internal fixation was tested in vitro using 20 paired equine third metacarpal bones with mid-diaphyseal osteotomies plated with six-hole broad ASIF compression plates. One of each pair was luted and all specimens were tested in static overload or cyclic loading at 75% of the ultimate breaking strength using four-point bending. Although no differences were measured in static overload tests between luted and non...