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.
Duncan JL, Dargie JD.The migratory route of infective Strongylus vulgaris larvae was determined: penetration of small and large intestine into the lumina of submucosal arteries, migration up the arterial tree, reaching the cranial mesenteric site by three weeks, where the larvae develop to the mature 4th stage. After 3-4 months they exsheath and the young adults migrate down the arteries towards the intestines, to the limit of arterial narrowing, from where they rupture from nodules into the lumen of the intestine. The prepatent period is about 6 months. The clinical syndrome was similar to, but less severe than t...
Thompson DB, Studdert MJ, Beilharz RG, Littlejohns IR.A fatal syndrome of certain Arabian foals which begins at about 25 days of age (range 14 to 46 days) and which runs a course of about 23 days (range 13 to 42 days) is described. The syndrome, which affected 17 foals on a single farm is further characterised by pneumonia, in some instances by dermatitis (dermatophilosis) and other infections, together with a progressive decline in health till death at about 49 days of age (range 34 to 77 days), despite intensive therapy. Four of the foals, on histopathological evidence, had adenviral pneumonia, in 2 foals there was histopathological evidence of...
Azzie MA.Contrary to common belief, Gastrodiscus aegyptiacus can be pathogenic to horses. History of cases of a particular stud, necropsy findings, diagnosis, and successful treatment with hexachlorophene and with dichlorvos are recorded. The presence of eggs can be established by a special flotation technique.
Coffman JR.Initial examination and therapy, and the avoidance of maltreatment are emphasized. Gastric decompression is of prime importance, after which no compound should be administered via stomach tube. Where large amounts of high starch grains are fed, primary acute gastric dilatation must be differentiated from that secondary to small bowel dilatation, by immediate gastric intubation and irrigation of the cardia with lidocaine. If cessation of pain and improvement of peristalsis and general attitude follow, the former state may be assumed. If pain persists and peristalsis does not improve markedly, o...
Van der Merwe JA.The revised NRC's Nutrient Requirements of Horses is changing the outlook on equine nutrition, dominated for so long by the traditional belief in oats. This has lead to the need for properly balanced diets, in the compounding of which dietary cubes offer the distinct advantage of providing a standardized diet of constant quality in keeping with modern knowledge. Additional factors are: longer storage, freedom from dust, palatability, refractoriness to mould infection, and facilitation of routine feeding. Cube size and hardness are important considerations for the manufacturer. Horses appear to...
Merritt AM, Bolton JR, Cimprich R.Pertinent questions regarding the history of a horse with diarrhoea are listed, as are diagnostic procedures that might be included in a complete clinical work-up. For purposes of discussion, diarrhoea is regarded as "acute" or "chronic" wherein the former concerns cases where the features of the disease are severe with progressive electrolyte imbalance, dehydration, toxaemia, or other life-threatening manifestations and the latter refers to cases that have been prolonged for a month or more. Patterns of disease, including results of diagnostic techniques, are stressed. In the "acute" category...
Drudge JH, Lyons ET, Tolliver SC.Controlled tests of the efficacy of bot-active compounds, dichlorvos, trichlorfon, trichlorfon butonate, and carbon disulfide on the larvae of Gasterophilus intestinalis and Gasterophilus nasalis during their migratory period in the tissue of the mouth of horses and ponies were completed on experimentally induced and naturally acquired infections. Against the experimental parasitisms in pony foals, the resin-pellet formulation of dichlorvos given on the feed at the dose level of 37 mg/kg, 2 formulations of trichlorfon given by stomach tube at the dose level of 40 mg/kg, another of trichlorfon ...
Rhim JS, Ro HS, Kim EB, Gilden RV, Huebner RJ.A horse skin cell line (E. Derm, NBL-6, CCL-57) was susceptible to focus formation by the Kirsten mouse sarcoma virus, feline sarcoma virus (ST stain) and the MSV pseudotypes with woolly monkey, gibbon monkey, RD-114, AT-124, baboon placenta and murine xenotropic (BALB/c 3T3 and C57L/JD) type-C viruses. Foci were detected within 5 days after infection and the transformed cells continued to produce infectious virus and group-specific antigen of their respective type-C leukemia viruses. The transformation efficiency of various type-C sarcoma viruses in horse cells was also very high.
Brand A, de Bois CH, Vandenhende R.Parenteral administration of 2.5-5 mg. of prostaglandin F2alpha to horses, 15 mg. to heifers or 25-30 mg to lactating cows and 15 mg. to sheep will induce regression of the corpus luteum (luteolysis) and a fertile oestrus within 48-72 hours. Because of their luteolytic effect prostaglandins may be used in various indications in the field of reproduction. An exception is the pig in which administration of prostaglandins does not induce luteolysis before D12 and therefore fails to induce oestrus. In horses, cattle and sheep, administration of prostaglandins during the first four days of the cycl...
Mansmann RA.Little has been written about the use of antibiotics in the horse. This article is based on personal experiences related to equine clinical medicine and literature review and certainly does not represent all the possible therapeutic regimens that can he employed in the horse. There are two concepts that this article will emphasize. First and most importantly, when an infective process is suspected in a patient, cul-tures and sensitivities are the most important determinations to be made prior to antibiotic therapy. Whether in the treatment of a single case or in the treatment of a herd problem...
Muir WW, Moore CA, Hamlin RL.The influence of various concentrations of CO2 and O2 in the inspired gases on minute volume (V), tidal volume (VT), and respiratory rate (breaths per min; BPM) was examined in nonanesthetized, nonsedated normal horses. The VT and BPM increased linearly in response to increases in inspired CO2 concentration and curvilinearly in response to decreases in inspired Os concentration. The V increased curvilinearly in response to both increases in inspired CO2 concentration and decreases in inspired O2 concentration.
Schumacher J, Bratton GR, Williams JW.The pudendal and caudal rectal nerves in four male and five female adult crossbred horses were anesthetized with a local solution. The injection site was located at the foramen for the caudal gluteal artery and vein in the sacrosciatic ligament. Twenty milliliters of local anesthetic solution were injected via a 15-cm, 18-gauge needle. Quantitative data on anesthesia were determined from these injections. Dye was injected with the anesthetic in four additional horses so that accurate placement of the solution could be determined at postmortem examination. Satisfactory anesthesia of the anus, p...
Caron JP, Eberhart SW, Nachreiner R.Articular cartilage explants from 3 horses were maintained in tissue culture to test the effects of a polysulfated glycosaminoglycan on proteoglycan biosynthesis. Cultures were exposed to concentrations of 0, 50, or 200 micrograms of the drug/ml for either 2 days or 6 days, and labeled with 35S, before measuring the content of sulfated proteoglycan in the culture media and in extracts of cartilage. In a second experiment, the explants were incubated with the isotope and subsequently exposed to the same concentrations of the polysulfated glycosaminoglycan for 4 days. Subsequently, the amount of...
Divers TJ.Regulation of renal blood flow is by both extrinsic and intrinsic systems. Intrinsic regulation occurs via the afferent and efferent arterioles and tubuloglomerular feedback mechanisms with activation of the juxtaglomerular apparatus. Mechanisms of acute kidney injury are frequently associated with changes in renal blood flow. Acute tubular necrosis and apoptosis are common in horses following ischemic or toxic insults and in sepsis-associated acute kidney injury. Sepsis-associated renal injury often has a complex mechanism of disease involving both functional and obstructive changes in intrar...
Jones S, Blackmore DJ.The distribution of the isoenzymes of aspartate aminotransferase (AST, E.C. 2.6.1.1.) in equine tissues has been studied to ascertain whether the organ of origin may be identified when the total AST activity of serum is raised. Most tissues contain 3 isoenzymes of cytoplasmic origin (cAST) with isoelectric points of 5.6, 5.7 and 5.9, and one isoenzyme of mitochondrial (mAST) origin with an isoelectric point of 9. Serum from horses with azoturia contained an additional cytoplasmic subform with an isoelectric point of 5.8. This form could not be generated by ageing, freezing and thawing or bindi...
Rogger P, Herrmann N, Ottiger H.The registration of adverse events after the use of immunological veterinary medicinal products (VMP) is the aim of the vaccinovigilance reporting system in Switzerland. Adverse events comprise suspected adverse reactions and lack of expected efficacy. Since the Institute of virology and immunology (IVI) is the competent authority for the regulation of immunological VMP in Switzerland, the reporting system is administrated by the IVI. In 2018, 162 reports concerning authorized immunological VMP were received. While most of the reports were submitted by the marketing authorization holders (79%)...
Puotunen-Reinert A, Huskamp B.A retrospective study on surgical cases of colic in horses (n = 216) revealed that 42 (19.4%) developed post-surgical diarrhoea. Salmonella spp. were isolated in 6 (16.2%) of the cases (n = 37) exhibiting diarrhoea. In 35.7% of the cases (n = 42) recovery from surgery was disturbed by other complications; 23.8% (10/42) died, 2 of which from primary acute diarrhoea due to salmonellosis. Most of the outbreaks of diarrhoea occurred in winter and spring. From the associated variables examined, the duration of colic signs revealed a significant difference between the cases which developed acute pos...
Wagner IP, Hood DM.To evaluate the effect of prolonged water exposure on tissue mass and solutes of outer and inner layers of the stratum medium, sole, frog, and the stratum medium (SMZA) zona alba layer of horses' hooves. SPECIMEN POPULATION: 10 hooves from 10 horses without foot abnormalities. Methods: Hoof wall tissue specimens were obtained and immersed for 10 days in distilled deionized water. Serial changes in mass were recorded during the immersion period. Subsequently, osmolarity and Na+, K, Cl-, and protein concentrations of the immersion solution were quantified. Results: Fully cornified outer hoof wal...
O'Connor M.Zoonotic diseases are those which originate in animals but are transmitted to humans often through an intermediate host such as a wild animal. In Australia Hendra virus (HeV) is a disease of horses with occasional human fatalities and which is spread by the fruit bat. This article explores the lessons learnt from managing the Queensland outbreak of HeV in 1994. The legal framework for the notification and management of prohibited matter including zoonotic diseases in Queensland and New South Wales has been strengthened by provisions in the Biosecurity Act 2015 (NSW) which create strong penalti...
Kibler ML, Pendell DL, Costanigro M, Traub-Dargatz J.Equine injury and disease cause two types of costs for those financially responsible for treating and caring for the infected horse(s); direct costs of treating the horse and indirect cost of lost use of the horse for a period of time to the user of the horse (daily horse use). Indirect costs are more difficult to estimate but pose significant financial implications for equine-owners/caregivers. Additionally, there exists a gap in existing research regarding the valuation of infectious treatment options in horses. Objective: To estimate the value a US horse-owner/caregiver places on daily hors...
Woodie JB, Ruggles AJ, Litsky AS.To evaluate 2 methods of midbody proximal sesamoid bone repair--fixation by a screw placed in lag fashion and circumferential wire fixation--by comparing yield load and the adjacent soft-tissue strain during monotonic loading. Methods: Experimental study. Methods: 10 paired equine cadaver forelimbs from race-trained horses. Methods: A transverse midbody osteotomy of the medial proximal sesamoid bone (PSB) was created. The osteotomy was repaired with a 4.5-mm cortex bone screw placed in lag fashion or a 1.25-mm circumferential wire. The limbs were instrumented with differential variable relucta...
Phelps S, Chong D, McKenzie E, Kiupel M, Gorman E.Clinical disease caused by infection with Listeria monocytogenes is rare in adult horses, and there is a paucity of ante-mortem clinicopathologic changes for this species reported in the literature. Confirmatory diagnosis is difficult and often requires post-mortem sampling of the brainstem. This report details a case of meningoencephalitis caused by Listeria monocytogenes in an adult American quarter horse gelding presenting with central neurologic signs. Pre-mortem analysis of the cerebrospinal fluid revealed a mononuclear, primarily lymphocytic, pleocytosis, which is a reported finding in o...
Mazan MR.The airways are the first part of the pathway in the oxygen transport chain that is critical to excellent athletic performance, and the lower airways are considered the final gatekeeper before oxygen enters the blood and carbon dioxide exits. Horses are blessed with large airways and lungs that allow them to be superb athletes, but the down side of this largesse on the part of evolution is that unless they are truly elite athletes they may withstand noninfectious disease of the lower respiratory tract for months to years before the owner or trainer notices. The two conditions of the lower resp...
Chen CL, Neilson JT, Kumar MS, Estes KS.Highly purified equine prolactin was prepared from equine pituitary glands (hypophysis) by serial extractions with water at pH 5.5, 0.1 M (NH4)2SO4 at pH 4.0, and 0.25 M (NH4)2SO4 at pH 5.5 to remove other hormones, and then finally with 70% ethanol at pH 9.3 to 10.0 to extract prolactin. Preliminary purification of the extract involved salting out other substances with 0.1% NaCl at pH 9.0. Prolactin was precipitated out by adding three times the volume of 95% ethanol at 4 C. This prolactin preparation had a biological potency of 24 IU/mg. Further purification by isoelectric focusing on a pH g...
Merritt AM, Xie H, Lester GD, Burrow JA, Lorenzo-Figueras M, Mahfoud Z.To evaluate the reliability of a method for inducing colic via small intestinal distention in horses and to examine the analgesic potential of bilateral electroacupuncture (EAP) at the Guan-yuan-shu (similar to BL21) acupoint. Methods: 5 healthy adult horses, each with a gastric cannula. Methods: A polyester balloon connected to an electronic barostat was introduced into the duodenum via the gastric cannula. At 2 specified intervals (before and after commencement of EAP), the balloon was inflated to a barostat-controlled pressure that induced signs of moderate colic. Each inflation was maintai...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the fruit (pericarps and seeds) of Hook f. (star anise tincture) when used as a sensory feed additive for all animal species. The product is a ■■■■■ solution, with a dry matter content of approximately 1.86%. The product contained on average 0.2588% polyphenols (of which 0.0229% were flavonoids, including 0.0036% rutin), anethole (0.018%) and estragole (0.00039%). The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)...
McMullen RJ, Gilger BC, Michau TM.To describe a surgical modification of deep lamellar endothelial keratoplasty (DLEK) and posterior lamellar keratoplasty (PLK) procedures, to facilitate surgery on standing horses under-sedation. Methods: Four client-owned horses, for which the owners declined surgery under general anesthesia, underwent standing corneal lamellar keratoplasty procedures for the treatment of deep corneal stromal abscesses. Methods: All four horses were placed in stocks and sedated with detomidine. Local eyelid and retrobulbar blocks were performed to provide local analgesia and akinesia, and each horse's head wa...
Mercier P, Alves-Branco F, Sapper Mde F, White CR.To evaluate the safety of an orally administered ivermectin and praziquantel paste with regard to variables associated with clinical findings, parturition, lactation, maternal care, and neonate viability in pregnant mares. Methods: 40 pregnant mares. Methods: Mares were randomly allocated into treatment (n = 20) and control (20) groups and administered a placebo or 3 times the therapeutic dosage of ivermectin (0.6 mg/kg) and praziquantel (4.5 mg/kg) at 14-day intervals until parturition. Physical examinations were performed on mares and their foals after parturition (on postpartum days 30, 60,...
Owen M, Ferjak EN, Cavinder CA, McCarty KJ, Yankey KC, Hart CG, Burnett DD, Dinh T, Lemley CO.The objective of this study was to determine the activity of steroid- and eicosanoid-metabolizing enzymes in horses with varying BCSs. The BCSs of twenty non-pregnant, anoestrous mares were determined prior to euthanasia, and tissue samples were collected from the liver, kidney, adrenal gland, ovary and endometrium. Cytochrome P450 1A (CYP1A), 2C (CYP2C), 3A (CYP3A) and uridine 5'-diphospho-glucuronosyltransferase (UGT) activities were determined using luminogenic substrates. The MIXED procedure of SAS was used to test the effect of BCS on enzyme activity and differences between tissues. Activ...
