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.
Lakritz J, Madigan J, Carlson GP.Hypovolemic hyponatremia attributable to severe fluid and electrolyte alterations was diagnosed in a foal with diarrhea. Subsequent consumption of water resulted in rapid reduction of serum sodium concentration and serum osmolar depression. Clinical signs of neurologic disease developed including blindness, loss of menace response, and seizures. Treatment of this condition with IV administered fluids included hypertonic saline solution (7.2%; 2 ml/kg of body weight), and frequent monitoring of serum electrolyte concentrations and osmolality resulted in gradual correction of the fluid and elect...
Squire KR, Adams SB, Conley R.The bladder of a 750-kg Clydesdale mare had everted through the urethra into the vagina immediately after parturition. The bladder was reinverted into the peritoneal cavity by an attending veterinarian, but 4 days later, the bladder was everted again in the vagina. The mare was able to void urine through both ureters, which could be seen in the mucosal surface of the bladder. The everted bladder had become edematous and could not be reinverted through the urethra. A considerable portion of the fundus was necrotic. The mare was administered xylazine epidurally to induce perineal analgesia, and ...
Stick JA, Nickels FA, Williams MA.Desmotomy of the accessory ligament of the deep digital flexor muscle (inferior check desmotomy) permitted Standardbred foals affected with flexural deformities to reach their full athletic potential. Long-term effects of inferior check desmotomy were examined in 23 Standardbreds over a 10-year period. Six of 11 foals that were treated surgically either raced 6 times and obtained a race record or were training sound (if yearlings). All 12 horses with flexural deformity that did not receive an inferior check desmotomy had an unfavorable outcome (no race record). Foals that had surgery performed...
Hance SR, Robertson JT.A 5-year-old Thoroughbred gelding was examined because of a small axillary wound sustained 5 days earlier and had resulted in extensive subcutaneous emphysema. Three days after admission, the horse's respiratory rate had increased to 72 breaths/min, and the horse appeared anxious and distressed. Thoracic radiography revealed pneumomediastinum and severe bilateral pneumothorax. Tube thoracostomy was performed on both hemithoraxes. The drains were connected to one-way suction valves and suction devices to decompress the thorax. A nasopharyngeal catheter was inserted, and oxygen insufflation was ...
Thompson DL, Rahmanian MS, DePew CL, Burleigh DW, DeSouza CJ, Colborn DR.Short-term patterns of growth hormone (GH) secretion and factors affecting it were studied in mares and stallions. In Exp. 1, hourly blood samples were collected from three mares and three stallions in summer and winter. Although GH concentrations varied in a pulsatile manner in all horses, there was no effect of sex or season (P greater than .1) on plasma GH concentrations and no indication of a diurnal pattern of GH secretion. In Exp. 2, 10-min blood samples were drawn for 8 h from 12 mares; after 6 h, porcine GH-releasing hormone (GHRH) was administered i.v. at 0, 45, 90, or 180 micrograms/...
Fisher MA, Jacobs DE, Grimshaw WT, Gibbons LM.In order to study the prevalence of benzimidazole-resistance in equine cyathostomes, 30 stables in south east England were selected according to strict criteria but with minimum bias to provide three matched groups of 100 horses. One group was treated with fenbendazole, one with pyrantel embonate and the third was left untreated. The overall efficacies of fenbendazole and pyrantel embonate, as judged by the faecal egg-count reduction test, were 56.3 and 95.8 per cent, respectively. The numbers of horses at individual stables were too small to draw conclusions at each stable, but whereas effica...
Jasko DJ, Little TV, Lein DH, Foote RH.Information pertaining to evaluation of single ejaculates of semen and records for 2 consecutive breeding seasons were obtained. In all, data for 99 individual breeding seasons (n = 43 Standardbreds and 56 Thoroughbreds) were evaluated. Included in each semen evaluation was examination of semen characteristics and computer-aided analysis of spermatozoal movement characteristics. On the basis of the analysis of breeding records for 4,175 mares (7,017 estrous cycles), a per-estrous cycle fertility rate was calculated from data for 96 of the breeding seasons. Stallions with lower fertility than t...
Dennis VA, Klei TR, Miller MA, Chapman MR, McClure JR.Ten helminth-free pony foals divided into three groups were used in this study. Eight foals were each experimentally infected per os with 50 Strongylus vulgaris infective larvae weekly for 4 weeks, at which time one foal died of acute verminous arteritis. The remaining seven foals subsequently received 50 S. vulgaris infective larvae every 2 weeks for an additional 20 weeks. Four of the infected foals remained untreated (Group 1) and three of the infected foals were given ivermectin at 8, 16 and 24 weeks post initial infection (Group 2). Two foals served as controls (Group 3). Foals in Group 1...
Weber JA, Woods GL.This article reviews the capabilities of transrectal ultrasonography for determining the distribution of fluid and tissue within stallion accessory sex glands. Emphasis is placed on describing the normal ultrasonographic appearance of the accessory sex glands, excurrent ducts, and pelvic urethra of stallions during rest, after teasing, and after ejaculation and using this information to detect glandular abnormalities.
McDonnell SM.This article includes a brief description of the reproductive patterns and specific behaviors comprising courtship and copulation in equids. The author then focuses on breeding behavior of the domestic stallion. Descriptions of normal breeding behavior under a variety of domestic management systems, comments on sexual behavior of donkeys and exotic equids, and the most common types and treatments of sexual behavior dysfunction are included.
Legrottaglie R, Agrimi P.Electrophoretic analysis in polyacrylamide gel (PAGE) of the equine rotavirus 106/88/LI/EQ, isolated from the diarrhea of an 18 day old foal was compared to the bovine strain NCDV. There was a notable difference in the migration of some segments of the viral RNA. Bands 2 and 3 of the equine rotavirus comigrated while there was a clear separation of segments 7, 8 and 9. Moreover, the migration of segments 1, 4 and 5 revealed a lower molecular weight than the corresponding segments of NCDV.
Divers TJ, Timoney JF, Lewis RM, Smith CA.A 12-year-old thoroughbred gelding died from diffuse global glomerulonephritis, 3 months after a lower respiratory infection from which Streptococcus zooepidemicus was isolated. Immunopathological studies (immunofluorescence, immunodiffusion, immunoperoxidase testing and immunoblotting) indicated the presence of an immune reactant renal disease associated with IgG antibody and streptococcal antigens.
Gasthuys F, Messeman C, De Moor A.The influence of hypertonic NaCl 7.2% infusion (4 ml/kg of body weight [BWT]) on plasma (PV) and blood (BV) volumes, sodium (Na), chloride (Cl), potassium (K) plasma concentrations, osmolality (Osm), total protein content (TP), packed cell volume (PCV) and red blood cell count (RBC) was studied in five standing and anaesthetized ponies (standard halothane anaesthesia). Arterial blood gases were followed in the anaesthetized ponies. Isotonic NaCl 0.9% (4 ml/kg of BWT) was used as a placebo in the standing ponies. Isotonic solution in the standing ponies induced few changes: only small decreases...
Hurtgen JP.The breeding soundness evaluation of a stallion is a thorough investigation of a stallion's libido, mating ability, and semen quality. The evaluation should include historical data about the medical aspects of the horse's performance and breeding career, observations and breeding behavior characteristics, collection and evaluation of semen, tests to determine freedom from infectious or contagious disease, and production of foals free of genetic defects. This information should allow the examiner to anticipate the impact of the stallion on the reproductive efficiency of a group of mares. The br...
Love CC.Ultrasonographic examination of the testis, epididymis, and spermatic cord of the stallion can be used to enhance the routine breeding soundness evaluation of the stallion. Normal ultrasonographic anatomy of the testes and associated structures are presented to aid the clinician in differentiating abnormalities of these structures.
Clay CM, Clay JN.The seasonal reproductive cycle of stallions is characterized by an annual regression and recrudescence in testicular function and concentrations of LH, FSH, and testosterone in serum. Maximum reproductive capacity occurs during the increasing day lengths of spring and summer. The annual cycle in LH secretion may reflect a seasonally associated and photosensitive reduction and replenishment in pituitary content of LH. Similar to other seasonal breeders, it appears that stallions may possess an endogenous circannual rhythm in reproductive function that is subject to manipulation by altering the...
Willoughby R, Ecker G, McKee S, Riddolls L, Vernaillen C, Dubovi E, Lein D, Mahony JB, Chernesky M, Nagy E.The response of horses exposed to three common respiratory viruses was studied by measuring tracheal mucociliary clearance rates in the trachea. Tracheal clearance rates (TCR) were determined before, during illness and following recovery in horses exposed to equine rhinovirus (ERhV-2), equine influenza virus (EIV) and equine herpesvirus (EHV-4) by means of lateral scintigraphs made following an injection of technetium-99m sulphide colloid into the tracheal lumen. In six horses exposed to ERhV-2, TCR remained within normal limits. Exposure to EIV resulted in reduced TCR in six of seven horses, ...
Doreau M, Boulot S, Bauchart D, Barlet JP, Martin-Rosset W.Voluntary food intake, milk yield and composition, and blood metabolites were measured during the first 2 mo of lactation in draft broodmares fed diets containing either 95% hay and 5% concentrates (Diet F) or 50% hay and 50% concentrates (Diet C). Voluntary food intake was higher for mares fed Diet C than for those fed Diet F (22.9 vs. 21.4 kg dry matter in wk 4). Both diets, especially Diet C, were eaten in amounts exceeding the energy requirements. Daily milk yield in wk 4 was 26.4 kg and 23.4 kg for mares fed Diets C and F, respectively. Milk fat and protein concentrations were higher (P l...
Rice L, Ott EA, Beede DK, Wilcox CJ, Johnson EL, Lieb S, Borum P.Oral tolerance tests were performed on 13 neonatal foals to determine their ability to digest disaccharides on d 1, 3 and 5 postpartum. Foals were assigned randomly to treatments consisting of 20% (wt/vol) solutions of either maltose, lactose, or sucrose, dosed at 1 g/kg of BW, or glucose, dosed at .5 g/kg of BW. After a 2-h fast, an initial blood sample was collected via jugular catheter. Foals were administered the appropriate solution orally, and blood was collected every 15 min for 1 h and then every 30 min for 3 h. Plasma glucose increased after dosing with lactose or glucose but not with...
Staempfli HR, Prescott JF, Brash ML.Four groups of two ponies, free of fecal Salmonella and Clostridium cadaveris, were treated as follows: Group A, control group; B, single nasogastrically administered dose of lincomycin (25 mg/kg) followed 48 h later by 3 L of C. cadaveris (10(9) organisms/mL); C, the same dose of lincomycin as group B; D, the same dose of C. cadaveris as group B on each of three occasions at 12 h intervals. Groups A and D remained healthy, but groups B and C developed severe colitis 48-56 h (B) or 72 h (C) after administration of lincomycin. Three ponies were euthanized and one in group B died. Clostridium ca...
Vandenbossche GM, Bouckaert S, De Muynck C, Mommens G, Van Zeveren A, Remon JP.The bioavailability and pharmacokinetics of ibuprofen, a nonsteroidal antiinflammatory drug, was studied in healthy Shetland ponies. Ibuprofen was administered IV, as a suspension, and as a solid solution oral paste to ponies from which food was withheld. The suspension paste was also administered to ponies that received hay and water ad libitum. Both formulations had an absolute bioavailability of about 80%. Bioavailability was not influenced by feeding.
Gunn HM, Fraher JP.The incidence of sarcocysts was examined in postural, propulsive and respiratory muscles from 74 horses ranging in age from mid-gestation to 14 years post-natal. Cryostat sections were stained for myosin adenosine triphosphatase (ATPase) at pH 9.5 and the type of muscle fibre containing sarcocysts was identified. Sarcocysts were found in muscles from three animals, all aged 1 year or more. Counts showed that they displayed no preference for any particular muscle. However, fibres with a high activity for myosin ATPase were preferentially colonized. Transverse sectional profiles of sarcocysts sh...
Golenz MR, Knight DA, Yvorchuk-St Jean KE.Nasogastric infusion of a human enteral feeding preparation was effective in reversing hyperlipemia in an anorectic miniature horse with an esophageal laceration. The nutrient preparation was delivered every 4 hours by gravity flow through a 12 F enteral feeding tube. Within 48 hours of initiating enteral nutrition, the hyperlipemia had resolved. Signs of intolerance to the preparation were not observed, and further weight loss was prevented. The use of a human enteral formula was a convenient and successful alternative for the treatment of hyperlipemia in the horse.
Dart AJ, Snyder JR, Pascoe JR, Farver TB, Galuppo LD.The signalment, clinical and laboratory findings of surgical conditions, treatment, and outcome of 102 cases of descending colon disease in horses were reviewed. Abnormal conditions were categorized as enteroliths, impactions, strangulating lipomas, fecaliths, foreign body obstruction, volvulus, nephrosplenic entrapment, and other conditions. Eleven breed categories of horses were seen during this period. Arabians, ponies, and American miniature horses were more predisposed to descending colon disease than other breeds (P less than 0.05). Female horses and animals greater than 15 years old wer...
Stick JA, Arden WA, Robinson RA, Shobe EM, Roth RA.Effects of 1 hour of colonic volvulus and 3 hours of reperfusion on concentrations of thromboxane (TXB2) and prostacyclin (6-keto-PGF1 alpha) in portal, pulmonary arterial, and jugular blood were determined by radioimmunoassay to assess the site of production and clearance of these eicosanoids from the circulation in 5 anesthetized ponies. Colonic volvulus had no significant effect on mean arterial pressure or TXB2 concentrations, but significantly (P less than 0.05) increased 6-keto-PGF1 alpha concentrations in all blood samples. Immediately after colonic reperfusion, all eicosanoid concentra...
Jasko DJ.This article outlines a basic method for conducting a stallion semen evaluation. After the removal of the gel fraction of the ejaculate, semen gel-free volume is determined, and any abnormality in appearance is noted. Concentration of sperm cells in semen can be determined with the use of either a hemacytometer or spectrophotometer after appropriate dilution of raw semen. The percentage of progressively motile sperm is evaluated promptly after collection of semen with the use of a phase-contrast microscope. The total numbers of sperm and progressively motile sperm in the ejaculate are calculat...
Binhazim AA, Harmon BG, Roberson EL, Boerner M.During routine necropsy of a 28-year-old horse with intestinal volvulus, numerous hydatid cysts were discovered in the liver. Viable protoscolices of Echinococcus granulosus were obtained from the cyst. As a 4-year-old, this horse had been imported from an area that is enzootic for equine hydatidosis.
Chuma T, Le Blois H, Sánchez-Vizcaíno JM, Diaz-Laviada M, Roy P.The major core protein, VP7, of African horsesickness virus serotype 4 (AHSV-4), the aetiological agent of a recent outbreak of the disease in southern Europe, was expressed in insect cells infected with a recombinant baculovirus containing a cloned copy of the relevant AHSV gene (S7). Analyses of its biochemical and antigenic properties confirmed the authenticity of the protein expressed. The high-level expression of VP7 under the control of the strong polyhedrin promoter of Autographa californica nuclear polyhedrosis virus induced disc-shaped crystals in infected insect cells. This enabled u...
Moeller S, Patan-Zugaj B, Däullary T, Tichy A, Licka TF.Laminitis is associated with failure of the suspensory apparatus of the distal phalanx (SADP) connecting the distal phalanx to the hoof wall. The specific aim of this study was to examine in vitro whether thinning of the hoof wall leading to increased deformability influences the damage of the laminar tissue created by loading of the hoof. Paired cadaver forelimbs from twelve horses were used. For each pair, the hoof wall from one hoof was thinned by 25%; this was ascertained by radiography. The contralateral hooves were used as controls. In a material testing machine, hooves were loaded in a ...
Marchant EA, Semevolos SA.The marginal transitional zone is peripherally located within the diarthrodial joint, and represents the interface of articular cartilage, periosteum, and the fibrous joint capsule. The purpose of this study is to characterize the protein expression of matrix and molecular regulators in the marginal transitional zone of foals having osteochondrosis (OC) compared to normal foals. Several families of proteins with known roles in cartilage and bone development are investigated, including matrix molecules, Wnt signaling, apoptotic factors and paracrine cell signaling molecules. Our results demonst...
Lisiecki P, Sobiś-Glinkowska M, Mikucki J.Under iron-restricted conditions staphylococcal strains could utilize in vitro several animals body iron sources in form of bovine haemoglobin, hemin, lactoferrin and transferrin, ovotransferrin, horse myoglobin ferritin and cytochrome C. Spectrum of utilized iron sources was not dependent on species affiliation and kind of siderophores system. Strains isolated from clinical materials utilized largest spectrum of animal iron body sources.
Trotter GW, Aanes WA.During an 8-month period, 3 horses were examined because of incomplete cryptorchid castration. Each horse had had surgery to remove 1 retained testis. In each case, the attending veterinarian believed castration had been adequately completed. History, rectal examination findings, and in 2 cases, high serum testosterone concentration were factors that led to the decision to do exploratory surgery on each horse. In each case, initial surgery had resulted in surgical removal of the tail of the epididymis, which was mistaken for testicular tissue.
Gupta AK, Singh BK, Yadav MP.Fifty aborted foetus samples were diagnosed for the presence of equine herpes virus-1 (EHV-1) by polymerase chain reaction (PCR) technique. Specific primer pair for amplification of a particular segment of EHV-1 DNA in gc region having 3 Hae III restriction endonuclease sites was used. A 409 base pair segment obtained as PCR amplification product in 9 samples was digested with Hae III to confirm the presence of EHV-1 as the infectious agent in aborted tissues. It was observed that PCR technique was more sensitive, specific and rapid than the conventional virological diagnostic methods.
Porter RM, Akers RM, Howard RD, Forsten-Williams K.Interleukin-1 (IL-1) and insulin-like growth factor-I (IGF-I), which have opposing effects on matrix metabolism within articular cartilage, are thought to play prominent roles in the pathogenesis of osteoarthritis. To better understand the link between these anabolic (IGF-I) and catabolic (IL-1) stimuli, we examined exogenous IL-1 regulation of the IGF-I signaling system of articular chondrocytes (ACs). Equine ACs from non-arthritic stifle joints were expanded in monolayer culture, encapsulated for 10 days in alginate beads, and stimulated as high-density monolayers with recombinant equine IL-...
Ogawa Y, Kanno M, Shimizu Y, Suzuki M, Yoshimoto T.A 56-year-old man presented with an unusual cranial penetration injury due to a horse's hoof. The CT number of the hoof was 269, and thus clearly not that of a wooden fragment or bone. An emergency operation was performed to remove the foreign body. The operation went well, and no infection developed. Eight months later he could walk unaided and had only mild disorientation.
Bull RW.Six equine lymphocyte alloantigen (ELA) specificities were defined by an international antiserum comparison test and workshop held in 1981. Twelve laboratories from four countries submitted 195 antisera for analysis. The antisera were exchanged among the 12 laboratories and tested in a standard lymphocyte microcytoxicity assay against the isolated lymphocytes at 1009 horses of several breeds. The data was pooled and analysed by a single computer analysis. The calculated chi 2 values of all cells with all antisera provided comparisons between antisera. Fifteen antisera clusters were formed by t...
Reck C, Menin Á, Batista F, Meira Santos PO, Miletti LC.Surra is an infectious disease caused by , which affects a large number of domestic and wild animal species. Infection control is based on rapid diagnosis followed by treatment of sick animals. This study aimed to evaluate a buffered antigen and rapid serum agglutination test (BA/Te) for the detection of anti- antibodies in serum samples of horses. For this purpose, 445 serum samples from horses were evaluated and the results compared with the diagnosis by CATT/. Our data show a sensitivity of 92%, specificity of 91% and a degree of agreement kappa () of 0.82 (95% CI: 0.771-0.877, < 0...
Waelchli RO, Ehrensperger F.Hydrops allantois was diagnosed in two Haflinger mares with severe abdominal distension. Both mares were seven months pregnant. Abortion was induced with two injections of prostaglandin six hours apart followed by further manual dilation of the cervix and administration of oxytocin the next day. There were 90 and 95 litres of fluid, respectively, in the allantoic cavities which resembled extracellular fluid with regard to concentrations of urea, creatinine, sodium, potassium, calcium, magnesium, phosphate and chloride, but not total protein. Both fetuses had severe brain abnormalities which we...
Xu Y, Zhang X, Peng P, Liu Y, Yu M, Xie L.Equine copivirus (EqCoPV) is a newly discovered parvovirus that infects equines. Currently, it is unclear whether this virus is prevalent in China. In the present study, serum samples were collected from equines in China and were processed for EqCoPV DNA detection by PCR. The results demonstrated that EqCoPV was circulating among the sampled equines, with a low detection rate of 0.94%. The genome sequence of one Chinese EqCoPV strain, UH26, was determined and used for genetic and phylogenetic analysis. The results demonstrated that UH26 has a close genetic relationship to EqCoPV strains from t...
Alim S, Cheppali SK, Laitaoja M, Talluri TR, Jänis J, Swamy MJ.Fibronectin type-II (FnII) family proteins are the major proteins in many mammalian species including bull, horse and pig. In the present study, a major FnII protein has been identified and isolated from donkey (Equus hemionus) seminal plasma, which we refer to as Donkey Seminal Plasma protein-1 (DSP-1). The amino acid sequence determined by mass spectrometry and computational modeling studies revealed that DSP-1 is homologous to other mammalian seminal plasma proteins, including bovine PDC-109 (also known as BSP-A1/A2) and equine HSP-1/2. High-resolution LC-MS analysis indicated that the prot...
Frost ML, Colton SW, Wertz PW, Downing DT.The C34, C36, and C38 dienoic omega-lactones were isolated from sebum of the horse (Equus caballus) and the double bond positions were determined by stepwise chemical dissection and analysis of the fragments. The structures found could be formed by delta 9-desaturation at the C18-stage of fatty acid biosynthesis followed by a second delta 9-desaturation when the chains reached C24, C26, C28, C30, or C32 and then addition of one to seven 2-carbon units. These findings provide insight into the dimensions and organization of the endoplasmic reticulum in cells of the sebaceous glands.
Burn JF.Little is known about the interaction of the hoof with the ground at the onset of stance phase although is it widely believed that high power collisions are involved in the aetiopathology of several conditions causing lameness. Objective: To answer 3 questions regarding the fundamental nature of hoof-ground collision: (1) is the collision process deterministic for ground surfaces that present a consistent mechanical interface (2) do collision forces act on the hoof in a small or large range of directions and (3) Is the hoof decelerated to near-zero velocity by the initial deceleration peak fol...
Science (New York, N.Y.)July 19, 1946
Volume 104, Issue 2690 53-54 doi: 10.1126/science.104.2690.53
Sulkin SE, Goth A, Zarafonetis C.Anesthesia, by ether, is effective in the treatment of western equine encephalomyelitis in mice. Of mice treated with deep ether anesthesia soon after the intracerebral injection of western equine virus, only 58 per cent developed the disease as compared with 92.4 per cent of control animals. When anesthesia was delayed the approximate length of the incubation period, 60 per cent of the animals developed the disease as compared with 92.4 per cent of the controls. In addition, ether anesthesia delays the development of central nervous system symptoms not only when administered soon after the in...