Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Fincham DA, Mason DK, Young JD.Horse erythrocytes are polymorphic with respect to L-alanine permeability. The present investigation compared the specificity, kinetics and cation-dependence of erythrocyte amino acid transport in two groups of thoroughbred horses, those with erythrocyte L-alanine permeabilities in the range 5-15 mumol/h per litre of cells (0.2 mM extracellular L-alanine, 37 degrees C) (transport-negative type) and those with L-alanine permeabilities in the range 450-700 mumol/h per litre of cells (transport-positive type). Transport-positive cells are shown to possess a novel high-affinity, stereospecific, Na...
Palmer JE.Few foals escape gastrointestinal disease during the first weeks of life. Diarrhea is an extremely common problem; fortunately, however, it is usually mild and self-limiting. When it is not, the underlying cause is often an infectious agent, such as rotavirus or Salmonella spp. Our understanding of many of the infectious agents causing neonatal diarrhea is far from complete. Gastric and duodenal ulcers are a less common disease of neonatal foals. There has been an apparent increase in the incidence of ulcer disease in foals during the past few years. The most effective way of decreasing seriou...
Skalka B, Svastová A.Two techniques were developed to detect antibodies against the exosubstance of C. equi called equi-factor. In the first technique serum samples are tested against native equi-factor produced by the growth of C. equi on agar medium. A positive result is manifested by the development of precipitation lines. The second test is based on neutralization of prepurified equi-factor by antibody, resulting in the inhibition of its hemolytic synergism with staphylococcal beta toxin. Sera (125 samples) from horses of different ages, kept in localities with a history of C. equi infections, were examined. T...
Sellers AF, Lowe JE, Cummings JF.Some support for both serotonin and substance P as biotransmitters in the equine large colon is presented. Close arterial injections of small quantities of each of these were effective, respectively, in stimulating marked increases in coordinated pressure peaks in the vicinity of the pelvic flexure, with modest (serotonin) or marked (substance P) increase in colon artery blood flow. Both the acaricide, amitraz, and the tranquilizer xylazine appeared to act on the equine large colon via yohimbine-sensitive alpha 2-adrenergic receptors.
Kemen MJ, Frank RA, Babish JB.An outbreak of an influenza-like illness affected approximately 1/3 of the 1050 race horses stabled at a standardbred racetrack and resulted in a 3-day suspension of racing. A/Equi-2 influenza virus was isolated from 1 affected horse and 8 of 10 horses sampled seroconverted. Threshold protective levels of HI antibody against A/Equi-2 influenza virus were not demonstrated in unaffected horses. Resistance in unaffected horses was assumed to result from other factors following previous exposure. Few of the horses had been vaccinated against equine influenza. It was felt that an outbreak of this m...
Richardson DW.The common conditions affecting the urogenital tract of the neonatal foal and their medical and surgical management are described. Early recognition and treatment of serious abnormalities are necessary for a successful outcome in the equine neonate.
Koterba AM, Drummond WH, Kosch P.The basic concepts of diagnosis and treatment in the abnormal neonatal foal are presented. Methods of restraint, sedation, and general nursing care are discussed, as well as more specific techniques of respiratory and circulatory system support.
Lyons ET, Tolliver SC, Drudge JH, Swerczek TW, Crowe MW.Prevalence of natural infections of parasites from the lungs of 488 dead Thoroughbreds in Kentucky was investigated. The horses varied from 1 to 32 years of age; 419 horses were from 215 farms and 69 horses were from 68 individual sources for which a specific farm was not identified. Examinations of the lungs were made from Mar 1, 1983 through Feb 29, 1984. Dictyocaulus arnfieldi was recovered from 56 (11%) of the horses. Other parasites found were larvae of Parascaris equorum in 37 (8%) and of Habronema/Draschia in 67 (14%) of the horses. The possible effect of ivermectin treatment on the pre...
Mollett TA, Elmore RG, Blanchard TL, Berg JN.This study was conducted to determine if Escherichia coli endotoxin was absorbed from the equine uterus and if exogenous progesterone and estrogen affected the absorption of intrauterine endotoxin. Six mature anestrous pony mares were used in three consecutive crossover experiments (Periods) with a 14 day recovery between each period. Mares were randomly assigned to one of two treatment groups (three mares per group) and received an intrauterine infusion of either saline or endotoxin. Treatment groups were reversed and readministered after 14 days completing a crossover design (Period 1). Duri...
Leitch M.Angular limb deformities are not uncommon in foals. Mild angular deviation due to laxity of supporting soft tissues often resolves spontaneously. However, external splinting or casting may be needed in severe cases or in those that do not resolve. When incomplete ossification of carpal or tarsal bones is the cause of the limb deformity, external support is mandatory to prevent further deformation and abnormal development of the bones. When epiphyseal and metaphyseal abnormalities cause axial deviation, surgical intervention is usually necessary. Circumferential periosteal transection and/or tr...
Koterba AM, Drummond WH.Provision of adequate nutritional support to the sick neonatal foal is a vital part of intensive care; frequently, however, it is very difficult to accomplish. In this article, current recommendations concerning both enteral and parenteral nutrition are discussed.
Soma LR, Laster L, Oppenlander F, Barr-Alderfer V.In 3 groups of horses with exercise-induced pulmonary hemorrhage (EIPH), comparisons of racing times and finishing positions were made between the 5 races before the horses were given furosemide and 5 races after furosemide administration. The horses were grouped according to 3 methods used to diagnose EIPH: group 1, observation of hemorrhage at the nostrils within 1 hour after a workout or race; group 2, observation of pulmonary hemorrhage only by endoscopic examination after a race or workout; and group 3, observation of hemorrhage at the nostrils during a race or immediately after a race. G...
Vaala WE.Other therapeutic agents used in foals for specific diseases are discussed elsewhere. The marked effect of species, age, and degree of maturity on drug metabolism in the neonate reinforces the danger of interspecies extrapolation of pharmacology, the need for information specific for the foal, and the necessity for monitoring drug levels in the individual. Suggested antimicrobial doses are listed in Tables 3, 4, and 6. Recommended doses of anticonvulsants and sedatives are listed in Table 8 and in the article "Intensive Care of the Neonatal Foal." The following are recommendations for drug the...
Reef VB.Cardiac disease in the equine neonate occurs infrequently. Murmurs are often heard in foals and are not considered significant unless they persist beyond 4 days of age. Congenital cardiac defects are the most common form of primary cardiac disease in the foal, with ventricular septal defects occurring most frequently. Other neonatal foal diseases such as ruptured bladders, white muscle disease, neonatal respiratory distress syndrome, and septicemia have secondary cardiac involvement.
Ikeda JS, Hirsh DC.An outbreak of equine salmonellosis occurred at the Veterinary Medical Teaching Hospital, University of California, Davis, between June 1981 and March 1982. Forty-four horses were infected with Salmonella saint-paul, a serotype rarely isolated from animals at the university before the outbreak. Unlike the isolates of S saint-paul obtained at the beginning of the outbreak, almost all strains isolated near the end were resistant to ampicillin, cephalothin, chloramphenicol, gentamicin, kanamycin, sulfadiazine, trimethoprim, and trimethoprim-sulfadiazine. A conjugal-resistance plasmid (R-plasmid) ...
Lyons ET, Tolliver SC, Drudge JH, Swerczek TW, Crowe MW.Prevalence of natural infections of the lungworm, Dictyocaulus arnfieldi, was investigated in Kentucky in 5,437 live equids (horses, ponies, and asses) on 91 farms by examination of fecal samples over a 15-month-period from January 28, 1983 to April 19, 1984. For the 91 farms investigated, asses only were examined on 1 farm; for the other 90 farms, examinations were made of horses on all of them, of ponies on 4 farms, and of asses on 9 farms. Larvae of D arnfieldi were found in fecal samples of 112 (2%) of 5,379 horses on the 90 farms of which 38% had greater than or equal to 1 infected animal...
Latimer CA, Wyman M.This discussion of normal and abnormal findings on routine ophthalmic examination of the foal should prove useful to the equine practitioner who must provide counsel to the concerned owner and/or breeder. Early diagnosis and treatment of ocular abnormalities improve the prognosis for continued function and aid determination of the significance of lesions observed in later life.
Klein L.A brief discussion of those aspects of neonatal physiology that pertain to anesthetic risk and selection of anesthetic techniques is followed by discussion of suggested techniques for anesthetic management in healthy foals. Preoperative preparation and management of foals with selected serious surgical conditions are also considered.
Hodgson DR, Rose RJ, Allen JR, Dimauro J.Muscle biopsy samples were collected from the left middle gluteal muscle of the horses participating in day 2 (speed and endurance test) of a three day event. Six Thoroughbred horses were biopsied the day before and within 30 minutes of completion of the speed and endurance test. Serial muscle sections were reacted histochemically for myosin adenosine triphosphatase activity after acid pre-incubation to demonstrate Type I, IIA and IIB fibers and the glycogen content in the individual fibers was assessed using the periodic acid Schiff (PAS) reaction. Total glycogen in muscle was measured fluoro...
Sullins KE, Stashak TS, Mero KN.Arteriovenous (ischemic strangulation obstruction, ISO) or venous (hemorrhagic strangulation obstruction, HSO) occlusions were created in the jejunum of 5 anesthetized horses and were left in situ for 1-, 2-, or 3-hour intervals. Segments were evaluated grossly for color, thickness, and motility. The horses were euthanatized, and the degree of mucosal slough, edema, congestion, and hemorrhage was determined histologically. Segments subjected to ISO became dark, but did not contain edema or hemorrhage. Segments subjected to HSO were characterized by progressive congestion, edema, and hemorrhage...
Dobson A, Gleed RD, Meyer RE, Stewart BJ.The distribution of blood flow to the lungs was measured with labelled microspheres injected into horses before and during anaesthesia. Anaesthesia was induced with glycerol guaiacolate ether and ketamine, and maintained with the spontaneous breathing of halothane in oxygen. In a preliminary group of six horses, flow distribution was observed during anaesthesia in sternal, dorsal and right lateral recumbency. In two other groups, each of four horses, the flow distribution with time during either sternal or right lateral recumbency was observed. A small, constant proportion of the 15 micron dia...
Liu IK, Cheung AT, Walsh EM, Miller ME, Lindenberg PM.The functional competence of peripheral blood and uterine-derived polymorphonuclear leukocytes (PMN) from 12 mares were analyzed for chemotactic responsiveness using a chemotactic chamber (filter) assay and for deformability by cell elastimetry analysis. Peripheral blood PMN obtained from control mares and from 8 mares experimentally inoculated via the uterus with 1 x 10(9) Streptococcus zooepidemicus had similar normal chemotactic responsiveness and were highly deformable before and at 12 hours after inoculation. Uterine PMN obtained 12 hours after uterine inoculation with S zooepidemicus fro...
Frymus T, Degórski A, Kowalski B, Crisman M.
Summary:
Serum lysozyme (LZM) activity and nitroblue tetrazolium (NBT) reduction capacity of circulating phagocytes were determined by the lysoplate technique and the microquantitative method, respectively. As blood donors 47 clinically normal Arabian foals ranging in age from 6 hours to 22 days and their 40 dams were used.
A significantly (p < 0.05) lower serum LZM activity was found in foals older than 24 hours, compared with the mares (40.84 U/ml ± 15.32 and 48,96 U/ml ± 17.9, respectively), but the LZM/phagocyte ratio was similar in foals and mares.
Circulating phagocytes from...
Devriese LA, Nzuambe D, Godard C.One hundred and twenty eight strains of Staphylococcus from lesions, mostly of the skin, in horses were identified and compared with 29 strains isolated from the healthy skin. The pathogenic species Staphylococcus aureus, S. intermedius and S. hyicus were found almost exclusively in lesions. Other species such as S. xylosus and S. sciuri were more frequently found on the healthy skin than in lesions. The S. aureus strains formed a very heterogeneous collection. Many of these strains were staphylokinase positive and rapidly coagulated bovine plasma. Such strains are rarely found in other animal...
Crowell-Davis SL, Houpt KA, Carnevale J.The feeding and drinking behavior of 11 mares and 15 foals living on pasture with free access to water was recorded during 2,340 15-min focal samples taken over 2 yr. Lactating mares on pasture spent about 70% of the day feeding. Foals began feeding on their first day of life. As they grew older, they spent progressively more time feeding, but still spent only 47 +/- 6% of the time feeding by 21 wk of age. Foals fed primarily during the early morning and evening. While grass formed the major proportion of the diet of both foals and mares, they also ate clay, humus, feces, bark, leaves and twig...
Woodger K, Stone EA.This article seeks to examine the history of equine surgery at the Ontario Veterinary College (OVC) in the context of the changing horse economy during the first half of the 20th century. We argue that despite the transition to livestock medicine, public health and small animal practice, the horse, especially as a surgical topic, retained a (diminished) place at OVC due to the lucrative new recreational equine market, the deep links between horses and veterinary medicine, and the equine focus for nearly half a century of Dr. W.J.R. Fowler, the College's primary surgical instructor.
Cohen ND, Carey VJ, Donahue JG, Seahorn JL, Harrison LR.Epidemiological and pathological findings of 433 late-term abortions associated with the mare reproductive loss syndrome (MRLS) in central Kentucky were identified by reviewing the records of the University of Kentucky Livestock Diseases Diagnostic Center. The distribution of dates of abortion was clustered during a brief period of time, presumably from a simultaneous environmental exposure. The most common pathological findings were microscopic pulmonary lesions consisting of squamous epithelial cells present in alveoli with or without concurrent infiltration of inflammatory cells (neutrophil...
Wilke K, Weimann M, Jung M, Geldermann H.10 different oligonucleotide probes were evaluated for DNA fingerprinting in horses. Five probes were able to detect polymorphic bands. The probes (GT)(8) , (GTG)(5) and (GGAT)(4) are most informative for individual identification and were used to analyze a population of Hannoveranian horses. The probability that two individuals have the same DNA fingerprint pattern is 1.2 × 10(-8) , 5.2 × 10(-10) and 1.5 × 10(-7) respectively. Using a combination of the three probes, paternity tests were performed with exclusion probabilities between 0.08% and 4%. ZUSAMMENFASSUNG: Oligonukleotide-Sonden fÃ...
Mariotti F, Cuteri V, Takai S, Renzoni G, Pascucci L, Vitellozzi G.Two horses with Rhodococcus equi infection were examined post mortem by an immunohistochemical method (peroxidase-antiperoxidase; PAP) with a monoclonal antibody (Mab 10G5) to the 15-17 kDa antigen of R. equi. One of the horses was also examined bacteriologically, R. equi being isolated in culture. Immunolabelling with this Mab was marked and widespread. On the other hand, the immunohistochemical reactivity of infected macrophages with a polyclonal antibody specific for lysozyme was slight. Thus, Mab 10G5 would appear to be a useful diagnostic reagent in R. equi infection, with or without cult...
Young DW, Smyth GB.The predominant form of gastrin in the antral mucosa of the stomach of virtually all species previously examined is the 17 amino acid peptide little gastrin (G17). This report describes the occurrence in equine antral mucosa of an immunoreactive form of gastrin with elution properties on Sephadex G-50 superfine similar to human unsulfated big gastrin (G34-I). This putative equine big gastrin was a major component of the gastrin immunoreactivity present. A second peak of activity in equine antral mucosa eluted in an identical manner to human little gastrin (hG17-I). Inhibition curves of equine ...
Harrison IW.Cecal torsion in horses is relatively rare. This clinical report describes cecocolic fold hypoplasia, producing increased cecal mobility, as a predisposing cause of cecal torsion in a horse.
Aceto H, Miller SA, Smith G.To determine time to first detection of Salmonella organisms in feces of animals after experimental infection PO and times to onset of diarrhea and pyrexia to evaluate a common method for identifying nosocomial infections on the basis of time of admission and onset of clinical signs (ie, the 3-day criterion). Methods: Meta-analysis. Methods: Cattle, horses, goats, and sheep experimentally infected PO with Salmonella enterica subsp enterica. Methods: Online databases were searched for published reports describing results of experimental infection of cattle, horses, goats, and sheep PO with salm...
Harkins JD, Karpiesiuk W, Lehner A, Woods WE, Dirikolu L, Carter WG, Boyles J, Tobin T.This report evaluates the pharmacological responses, urinary detection and mass spectral confirmation of ropivacaine in horses. Ropivacaine, a potent local anesthetic (LA) recently introduced in human medicine, has an estimated highest no-effect dose (HNED) of about 0.4 mg/site as determined in our abaxial sesamoid block model. Apparent ropivacaine equivalents were detectable by ELISA screening using a mepivacaine ELISA test after administration of clinically effective doses. Mass spectral examination of postadministration urine samples showed no detectable parent ropivacaine, but a compound i...
Van Hoogmoed LM, Snyder JR, Nieto JE, Vatistas NJ, Harmon FA.To determine efficacy of an extracorporeal circuit to maintain a segment of equine large colon for 3.5 hours and to evaluate the effect of low arterial flow on histologic and metabolic variables. Methods: Segments of large colon from 15 healthy adult horses. Methods: The pelvic flexure was surgically removed and maintained in an isolated circuit. In the control group, tissue was evaluated for 3.5 hours, whereas in the low-flow group, arterial flow was reduced to 20% of baseline for 40 minutes followed by 2 hours of reperfusion. Various metabolic and hemodynamic variables were evaluated at 30-m...
DePew CL, Thompson DL, Fernandez JM, Southern LL, Sticker LS, Ward TL.Concentrations of prolactin, glucose, insulin, urea N, and total amino acids in plasma of stallions after ingestion of pelleted feed were compared to those after direct gastric administration of water, NaCl, egg albumin, or corn starch (Exp. 1) or water, egg albumin, hydrolyzed casein (Amicase), or a mixture of indispensable amino acids (Exp. 2). Stallions were fed once daily (75% pellet and 25% hay) at 1500 for 30 d. On d 22, 24, 26, 28, and 30, blood samples were collected every 30 min from 1 h before through 4 h after treatment, which occurred at 1100. In Exp. 1, there was a positive secret...
Pohlin F, Edinger J, Jenner F, Egerbacher M.To describe the anatomic and histologic features of the collateral ligaments (CLs) of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in cadaveric limbs obtained from nonlame horses and to compare the histologic findings with the ultrasonographic appearance of the CLs. Methods: Medial and lateral CLs of the MCP and MTP joints of 28 limbs (16 forelimbs and 12 hind limbs) from 9 adult nonlame horses euthanized for reasons unrelated to the study. Methods: 26 limbs of 8 horses were examined by ultrasonography immediately after euthanasia. Postmortem gross and histologic examinat...
Hay AN, Wagner B, Leeth CM, LeRoith T, Cecere TE, Lahmers KK, Andrews FM, Werre SR, Johnson AL, Clark CK, Pusterla N, Reed SM, Lindsay DS, Taylor S....Equine protozoal myeloencephalitis (EPM) is a debilitating neurologic disease affecting horses across the Americas. Gaps in understanding the inflammatory immune response in EPM-affected horses create difficulties with diagnosis and treatment, subsequently negatively impacting the prognosis of affected horses. The purpose of the current study was to evaluate circulating levels of the inflammatory immune marker soluble CD14 (sCD14), in horses with EPM (n = 7) and determine if they differed from healthy neurologically normal horses (n = 6). Paired sera and cerebrospinal fluid (CSF) samples were ...
Neelis DA, Roberts GD.The many advancements in ultrasound technology, including spatial compounding, harmonic imaging, multidimensional and extended field-of-view images, and improvements in transducer capabilities, are used to enhance the ultrasonographic examination of the equine patient. The improvements in software and hardware capabilities help overcome artifacts, improve image quality, and allow better documentation of the examination for follow-up studies. In addition, the ability of smaller, more portable machines to produce better images is ideal for the ambulatory practice setting.
Smyth GB, Brown RG, Juzwiak JS, Swaim SF, Vaughan JT.A vascularized full-thickness Estlander flap was used to repair a defect involving approximately 40% of the left lower lip of a colt. Postoperative problems were (1) providing nutritional support, (2) minimizing movement at the surgical site, and (3) partial wound dehiscence resulting in a salivary fistula. The surgical site healed well and the colt was left with a fully functional and cosmetic lower lip.
Potter K, Anez D.A 17-year-old Quarter Horse mare was examined to determine the cause of a vulvar mass. Differential diagnoses for the swollen, ulcerated tissue included hypersensitivity reaction to insect stings or bites and cutaneous neoplasia. During the next 4 months, the mass enlarged involving the skin of the perineum and ventral aspect of the abdomen with secondary dependent edema of both hind limbs. Histologic examination of biopsy and necropsy specimens revealed changes consistent with a diagnosis of mycosis fungoides (cutaneous T-cell lymphoma). Diagnostic features included invasion of neoplastic lym...