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.
Whyte A, Allen WR.Pre- and post-implantation endometrial tissue was removed from equids at known stages of pregnancy. Thin sections of this material were reacted with fluorescein conjugates of several lectins. Two lectins in particular, with specificities for L-fucose and N-acetylglucosamine, reacted strongly with the endometrial epithelium. The reaction for N-acetylglucosamine occurred in small patches on the endometrial epithelium and extended to cover the entire epithelial surface and endometrial glands after implantation. L-Fucose was observed in larger surface deposits particularly at the openings of endom...
Galan JE, Timoney JF.Purpura hemorrhagica is an acute disease of the horse characterized by edema of the head and limbs, leucocytoclastic vasculitis, petechial hemorrhages in mucosae, musculature and viscera, and sometimes glomerulonephritis. It is usually associated with strangles, an upper respiratory tract disease of the horse caused by Streptococcus equi. We have detected and characterized immune complexes in the sera of horses with poststrangles purpura hemorrhagica by using PEG precipitation and Western blot analysis. The immune complexes contained IgA and S. equi-specific antigens similar to those found in ...
Eldjarn L, Broughton PM.Eight analytes (Ca, Cl, cholesterol, glucose, Mg, K, Na and urate) have been determined in one horse serum masterlot by up to six different procedures: (i) by so-called definitive methods; (ii) by a group of reference laboratories using a variety of analytical methods; (iii) using the results of two independent external quality assessment schemes; (iv) by transferring values from a human serum standard reference material analysed by definitive methods; (v) by similar transfer of values from several batches of horse reference serum previously analysed by definitive methods; and (vi) as in (v) b...
Morris DD, Meirs DA, Merryman GS.A prospective study was performed to determine the incidence and associated maternal and managemental factors of failure of passive transfer (FPT) in foals on a breeding farm. The zinc sulfate turbidity test (ZSTT) and latex agglutination test (LAT) were compared for accuracy in estimating serum immunoglobulin (Ig)G of foals, as determined by single radial immunodiffusion (SRID). Complete past and present foaling histories of 136 Standardbred mares were obtained. All foalings were witnessed by farm attendants, and colostral samples were collected from mares within 2 hours after parturition. Fo...
Yovich JV, Powers BE, Stashak TS.The intervertebral disks and adjacent vertebral bodies of the 2nd to 7th cervical vertebrae from 17 horses (3 months to 19 years of age) were examined grossly and by light microscopy. In each specimen, the disk tissue was fibrocartilagenous centrally and became more fibrous peripherally, but without a distinct demarcation between the nucleus pulposus and anulus fibrosus. Demarcation between the anulus fibrosus and the dorsal longitudinal ligament was not apparent. With increasing age of the horses, cellularity of the central fibrocartilagenous portion of the disk decreased. The caudal end plat...
Engelking LR, Anwer MS, Lofstedt J.Fasting is associated with unconjugated hyperbilirubinemia in several species, including the horse. Studies in ponies showed that a 3-day fast decreased plasma clearance of bilirubin, cholic acid, and sulfobromophthalein (BSP). Since these organic anions are conjugated with different substrates, it is possible that observed differences in plasma clearance result from a general decrease in hepatic conjugating capacity during the animals' fasting. To test this hypothesis, the effects of a 3-day fast on plasma clearance of IV injected BSP (4.4 to 5.1 mg/kg), which is conjugated to glutathione, an...
Woods WE, Chay S, Houston T, Blake JW, Tobin T.The efficacy of testing for illegal drugs in race horses was surveyed by evaluating 27 questionnaires received from 28 racing jurisdictions polled. Large variations in the number of samples tested and drugs detected were reported. Some jurisdictions reported only illegal medications, whereas others also reported permitted medications. To facilitate comparison, stimulants, depressants, local anesthetics, narcotic analgesics, and tranquilizers were classified as hard drugs. Other drugs, which are legal in some jurisdictions, were classified as soft. To evaluate the efficacy of testing, positive ...
Wyn-Jones G.The value of radiology as part of an examination of the equine head is emphasised and the radiological appearances of more commonly occurring conditions are described. Even the normal anatomy of this complex site is subject to great variation and the aspiring radiologist should, therefore, have a good knowledge of the possible normal variations. A flexible approach must be used rather than a limitation to one or two ritual projections. The use of contrast media, wherever it might be useful, is advocated so that the maximum amount of information may be obtained from each examination. Finally, e...
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...
Essén-Gustavsson B, Lindholm A.Muscle biopsies were taken from the middle gluteus muscle of 36 Standardbred horses. Twelve of the horses were inactive, while 24 were actively trained and raced. Twelve of the trained horses were moderate performers, with a mean racing time of 1 min 21 secs per km (741 m/min) and the other 12 were excellent performers, with a mean racing time of 1 min 16 secs per km (789 m/min). The percentage and mean area of Type I fibres were similar in all three groups of horses. Marked differences were found among the subgroups of Type II fibres. The well-trained horses had a higher proportion of Type II...
Mair TS, Lane JG, Lucke VM.The clinical and post mortem features of 11 cases of lymphosarcoma involving the thoracic cavity are reviewed. The clinical findings included inappetence, weight loss, pectoral oedema, dyspnoea, pleural effusion and distension of the jugular veins. Dysphagia was present in three cases. At post mortem examination lesions were found in the abdomen as well as the chest in eight cases; clinical signs of abdominal disease were present in two cases. The features of nine other similar cases recorded in the literature are reviewed.
Thompson NE, Bergdoll MS, Pattee PA.The factor in normal sera primarily responsible for the enhancement of transfection (and transformation) of Staphylococcus aureus was identified as fibronectin. Serum samples which were depleted of fibronectin by affinity chromatography showed a marked decrease in enhancing activity. Fibronectin isolated from sera of several animal species demonstrated enhancing activity.
Silberzahn P, Dehennin L, Zwain I, Reiffsteck A.Follicular fluid was obtained from equine follicles at different stages of development as determined by ultrastructural study. Gas chromatography-mass spectrometry associated with stable isotope dilution permitted the demonstration of high levels of 4-estrene-3,7-dione and 17 beta-hydroxy-4-estren-3-one, 17 beta-hydroxy-4-estren-3-one levels often being about 10 times higher than those of testosterone. These findings suggest that in the mare ovary, an aromatizing pathway may proceed using these 19-norsteroids as intermediates. As a consequence of this high level of 19-norsteroids, testosterone...
McLean RG, Frier G, Parham GL, Francy DB, Monath TP, Campos EG, Therrien A, Kerschner J, Calisher CH.A study was undertaken to investigate an increase in reported cases of clinical encephalitis due to eastern equine encephalitis (EEE) virus in horses and to determine the natural vertebrate hosts of that virus. Horses, birds, and small mammals were sampled at sites in a contiguous area in St. Joseph and Kalamazoo counties, Michigan, from 25 August to 5 September 1980. Serum samples from four horses acutely ill with encephalitis and 16 of 39 pasture mates of ill horses had neutralizing (N) antibody against EEE virus (46.5%); no viruses were isolated from these 43 sera. None of 24 draft horses f...
Trenfield K, Spradbrow PB, Vanselow B.DNA was extracted from 14 equine sarcoids, electrophoresed and hybridised with a radioactively labelled probe of bovine papillomavirus type I (BPV 1) DNA under conditions of low stringency. Twelve sarcoids contained sequences of DNA that hybridised with the probe and that comigrated with BPV 2 DNA. The viral DNAs in four of these sarcoids differed from BPV 1 and BPV 2 DNA on restriction endonuclease analysis. One of four cell lines derived from sarcoids also contained BPV 1 related DNA. The results confirm the frequent presence in equine sarcoids of unintegrated papillomaviral DNA and suggest ...
Brock KA.A pharyngeal performation, probably associated with endotracheal intubation, occurred in a healthy 4 1/2-month-old colt. Inhalation anesthesia was carried out for elective surgery, but acute cervical cellulitis, pleuritis, and pneumonia developed after the surgery. Antibacterial and supportive therapy was ineffective.
Trim CM, Colbern GT, Martin CL.Intraocular pressure was measured with a MacKay-Marg tonometer in eight horses following auriculopalpebral nerve block and topical application of lignocaine. Measurements were recorded before and after xylazine, 1.1 mg/kg intravenously, every two minutes for 16 minutes after administration of ketamine, 2.2 mg/kg intravenously, and after recovery from anaesthesia. Before xylazine, intraocular pressure was 17.1 +/- 3.9 and 18.4 +/- 2.2 mm Hg in the left and right eyes, respectively. Intraocular pressure tended to decrease after administration of xylazine and ketamine, with a significant decrease...
Pipers FS, Reef V, Wilson J.Ventricular septal defects in a foal, a 2-year-old filly, and 2 calves were demonstrated with M-mode and two-dimensional real-time echocardiography. The studies were performed with the animals unsedated, either standing or in lateral recumbency. Cardiac windows were located between the 4th and 7th intercostal spaces, approximately at the level of the olecranon. In each case, the septal defect was visualized high in the membranous portion of the interventricular septum. Defects were visualized by use of sector scanning or linear-array ultrasonic equipment, with transducer frequencies of 2.25 to...
Bechert U, Rohde J, Freer H, Wagner B.SpayVac is an immunocontraceptive vaccine based on porcine zona pellucida (pZP) antigens and uses a patented liposome formulation (VacciMax or DepoVax). It has delivered single-dose, long-lasting (4-10 years) immunocontraception in several species. Previous studies have demonstrated a positive correlation between levels of pZP antibodies produced and contraceptive effect; however, individual mares that were consistently infertile did not necessarily have the highest antibody titers. The objective of this study was to identify potential differences in specific immunoglobulin G (IgG) isotype res...
Munk Z, Dusek J.The fertility problems were studied in the herd of the English Thoroughbred horse on the Napajedla stud farm. Breeding records for the period from 1880 to 1972 were used as the starting data. The survey comprised 32 stallions. The relationship between fertility and the number of matings was calculated by the chi 2 quantity. The calculated values are highly variable. However, it is generally seen in most of the stallions that the number of matings per heat (i. e. one or several matings) had no significant influence on the pregnancy of mares and on the fertility values of the stallions. A higher...
Stewart F, Leigh SE, Thomson JA.Complementary (c)DNA libraries have been made from horse pituitary gland and endometrial cup tissues with the aim of isolating the genes for the horse gonadotrophins (FSH, LH and CG) and growth hormone (GH). Southern (DNA) and Northern (RNA) blotting techniques were used to demonstrate that several heterologous (human and ovine) cDNA probes would be adequate for isolating the horse genes. A human cDNA probe was then used to isolate the horse gonadotrophin alpha-subunit cDNA from the pituitary and endometrial cup libraries. The nucleotide sequences from both tissue sources were identical, there...
Robertson JT, Copelan RW.The authors discuss the surgical treatment of selected diseases of the upper airway of the racehorse. Although most of these conditions occur commonly and are easily diagnosed, their surgical management is often less straight-forward and may be surprisingly controversial. The authors' intent is to provide an overview of these problems and give some information regarding current treatment options.
Vacek JR, Macharg MA, Phillips TN, Foerner JJ, Everett KA.A 3-month-old Thoroughbred colt was presented with signs of colic. Findings from physical examination, abdominal paracentesis, abdominal radiographs and clinical pathology revealed uroperitoneum secondary to a calculus obstructing the urethra and causing subsequent urinary bladder rupture. Analysis of the calculus demonstrated a tissue center with outer concretions composed primarily of struvite.
Ruppert S, Lee JK, Marsh AE.A 6-year-old female captive zebra (Equus zebra) had a three-year history of slow progressive neurologic signs that recently worsened with hind limb ataxia, head tilt, and circling. Gross examination including the brain and spinal cord were unremarkable. On histopathology, the brain and brainstem had multiple random areas of severe lymphoplasmacytic meningoencephalitis associated with numerous 15-25 μm in diameter protozoal cysts with a discernible outer wall containing numerous 2 × 4 μm oval to crescent-shaped organisms. Immunohistochemistry and PCR identified the presence of Neospora or...
van Veenendaal JC, Speirs VC, Harrison I.A surgical technique of open drainage, using penrose drains and pressure bandages, was used for the treatment of hygromata in four horses. In 3 cases with hygroma of the carpus, one with a secondary infection, there was complete resolution of the condition whereas in the one case with hygroma of the elbow resolution was more protracted because of difficulties in bandaging. The cosmetic and functional results after operation were most satisfactory.
Sieme H, Klug E, Bader H.Equine ejaculates are significantly characterized by widely varying parameters especially in those of practical relevance for equine Al. Therefore it is of interest for practical purposes to get subpopulations of concentrated, vital, and competent spermatozoa from the origin ejaculates. Special preparation of the donor stallions will stabilize sperm output. Fractionated semen collection from stallions supplies sperm enriched seminal fractions very useful to work with further in semen preservation. Most important to achieve a concentrated sperm subpopulation are semen manipulations post ejacula...
Bolat D, Yıldız D, Bahar S, Yürüker S, Kaymaz F, Ilgın C, Bozkurt EÜ, Karahan S, Sabancı SS.We investigated the microscopic structure of transverse sections of the oculomotor, trochlear and abducens nerves of Arabian foals using stereological methods. Bilateral nerve pairs from 2-month-old female Arabian foals were analyzed. The tissues were embedded in plastic blocks, then 1 µm thick sections were cut and stained with osmium tetroxide and methylene blue-azure II. Stereology was performed using light microscopy. Morphometry showed that the right and left pairs of nerves were similar. The transverse sectional areas of the oculomotor, trochlear and abducens nerves were 1.93 ± 0.19 mm...
McBeath DG, Wells PW, Eyre P, Hanna CJ.This paper attempts to relate the practicalities of vaccine development to the ideals which should be aimed for in a new vaccine. The type of immune response induced is dependent upon the nature of the antigen in the vaccine and the site and timing of its presentation to the immune system. In this respect the influence of age, maternal immunity and antigenic competition are discussed. The possible side effects associated with vaccination are defined and vaccines which are currently available for horses are reviewed. These vaccines are mostly for the prevention of respiratory disease. Finally, ...
Sharp DC, Wolfe MW, Cleaver BD, Nilson J.The process of sexual recrudescence in the springtime in mares is characterized by renewal of follicular growth and acquisition of steroidogenic competence. Concomitant with renewal of follicular steroidogenesis is re-establishment of LH biosynthesis and secretion. Research results from our laboratory indicate that increased estradiol and LH secretion occur in close temporal association before the first ovulation of the year. Therefore, the hypothesis tested in this experiment was that estrogen administration to ovariectomized pony mares during the equivalent time of early vernal transition wo...
Doige CE.A midsagittal centrum cleft of T5-6, malformation and fusion of T3-7, intra- and extraspinal cyst, and myelodysplasia were found in a 3-month-old female Arabian foal that had experienced posterior ataxia since birth. Based on studies in other species, ecto-endodermal adhesions early in embryogenesis leading to formation of an enterogenous cyst is the most probable pathogenesis.
Kamphues J, Meyer H, Liebler EM, Johannsen A.Anamnesis and clinical signs of horses form five different stables after ingestion of ionophores are reported and techniques of feed examination are described. Within a few hours or days after feeding of new types or batches of concentrates horses fell ill. They showed colic-like symptoms with intense sweating and ataxia. Most of the sick animals died within a short time span. Samples of the concentrates were analysed and different types and amounts of ionophores were detected. In four cases contamination by monensin in concentrations of less than 5 mg to 679 mg/kg feed were found. One feed sa...
Nyquist NF, Burri L, Jensen RB.Supplementation with marine-derived n-3 long-chain polyunsaturated fatty acids (LC PUFAs), eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) is linked to beneficial health effects in both humans and horses. Krill oil (KO), which is extracted from the Antarctic krill (Euphausia superba), is well documented as a safe and biologically available dietary supplement in humans and several animal species, but there is a lack of documentation regarding its effect as a dietary ingredient for horses. The objective of this study was to test whether KO as a dietary supplement h...
Thway TM, Wolfe MW.Primates and equids are the only species known to express the placental glycoprotein hormone, chorionic gonadotropin (CG), a heterodimeric glycoprotein composed of an alpha subunit linked to a hormone-specific beta subunit. The regulatory mechanisms involved in the induction of equine glycoprotein alpha subunit gene expression have not been identified. Epidermal growth factor (EGF) receptor is known to transduce signals that alter a number of different cellular functions (cell proliferation, differentiation, hormone secretion, and gene regulation). In the present study, we investigated the reg...
Walker N, Cater M, Bourg B, Devall H, Sarver M.Due to the increased awareness of animal welfare issues and sensitized attitudes throughout society, youth animal projects provide a unique opportunity to assess and impact youth understanding and attitudes regarding animal welfare. Animal ethics training is not an uncommon requirement for participants in 4-H livestock programs. However, participants in 4-H horse projects are not universally held to the same standard. The purpose of this study was to assess youth knowledge, attitudes, and confidence in understanding of equine welfare at the 4-H state horse show, as well as to determine the bel...