Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Galuppo LD, Stover SM, Jensen DG, Willits NH.To compare drilling, tapping, and screw-insertion torque, force, and time for the 4.5-mm AO and 6.5-mm Acutrak Plus (AP) bone screws, and to compare the mechanical shear strength and stiffness of a simulated complete lateral condylar fracture of the equine third metacarpal bone (MC3) stabilized with either an AO or AP screw. Methods: In vitro biomechanical assessment of screw-insertion variables, and shear failure tests of a bone-screw-stabilized simulated lateral condylar fracture. Methods: Eight pairs of cadaveric equine MC3s Methods: Metacarpi were placed in a fixture and centered on a biax...
Gardner SY, Papich MG.The pharmacokinetics of cefepime, a new fourth generation cephalosporin with enhanced antibacterial activity, was examined in neonatal foals and adult dogs. Cefepime was administered intravenously (i.v.) at a dose of 14 mg/kg to five neonatal foals and six adult dogs. Blood samples were collected in both groups of animals and plasma cefepime concentrations measured by reverse-phase high-performance liquid chromatography (HPLC). Cefepime concentrations in both groups of animals were described by a two-compartment pharmacokinetic model with elimination half-lives of 1.65 and 1.09 h for the foal ...
Bailey SR, Cunningham FM.Accumulation of equine eosinophils at sites of parasite infestation or allergic inflammation depends upon their adherence to vascular endothelial cells and subsequent migration through the endothelium and extracellular matrix. This study has examined whether cytokines, which cause endothelial cell-dependent eosinophil adherence in other species, and histamine and substance P, which increase adherence of equine eosinophils to protein coated plastic, induce equine eosinophil adherence to cultured equine digital vein endothelial cell (EDVEC) monolayers. The EDVEC monolayers were stimulated with r...
Traub-Dargatz JL, Kopral CA, Seitzinger AH, Garber LP, Forde K, White NA.To estimate the national incidence of, operation-level risk factors for, and annual economic impact of colic among horses in the United States during 1998 and 1999. Methods: Epidemiologic survey. Methods: 21,820 horses on 1,026 horse operations in 28 states. Methods: Horses were monitored for colic for 1 year, and results were recorded in a log that was collected quarterly. Operation-level data were collected via 4 on-site personal interviews. Associations between colic and independent variables adjusted for size of operation were determined. Results: Annual national incidence of colic in the ...
Freeman DE, Schaeffer DJ.To test the hypothesis that strangulation of the small intestine by a lipoma or in the epiploic foramen is more common in older horses. Methods: Retrospective study. Methods: 46 horses. Methods: Ages of horses with strangulation of the small intestine by a lipoma (n = 29) or in the epiploic foramen (17) were compared with ages of 79 horses with miscellaneous small intestinal lesions. Effects of increasing age on risk of the diseases of interest were examined by use of logistic regression and a 1-sided trend test for binomial proportions. Results: Mean age of the horses with strangulation in th...
Roussel AJ, Cohen ND, Hooper RN, Rakestraw PC.To determine risk factors associated with development of postoperative ileus in horses undergoing surgery for colic. Methods: Case-control study. Methods: 69 horses that developed ileus after surgery for colic and 307 horses that did not develop postoperative ileus. Methods: Signalment, history, clinicopathologic data, treatment, lesions, and outcome were obtained from medical records. Results: Variables associated with increased risk of postoperative ileus included age > 10 years, Arabian breed, PCV > or = 45%, high serum concentrations of protein and albumin, anesthesia > 2.5 hours'...
Heinzerling LM, Feige K, Rieder S, Akens MK, Dummer R, Stranzinger G, Moelling K.Preclinical studies investigating new therapeutic principles against melanoma are presently being carried out in mouse models; however, these are not optimal. Here we describe a novel animal model using gray horses. These animals spontaneously develop metastatic melanoma that resembles human disease and is thus highly relevant for preclinical studies testing new immunotherapy protocols. We found that injection of plasmid DNA coding for the human cytokine interleukin 12 into established metastases induced significant regression in all 12 treated lesions in a total of 7 horses. Complete disappea...
Dowling BA, Dart AJ, Trope G.Three horses with severely comminuted, open facial bone fractures and one horse with a comminuted, open orbital rim fracture were referred for treatment. Severe facial bone asymmetry and epistaxis were apparent in all cases and subcutaneous emphysema was present in two, however physical and neurological examinations were otherwise normal. Radiography and endoscopy were of some use in assessing the degree of damage, although the true extent of the damage was more apparent at surgery. Surgical reduction of the fractures was recommended to maximise cosmetic and functional outcome. After surgical ...
Röthlisberger U, Kaegi B, Geyer H, Auer JA.The annular ligament constriction is characterized by a disproportion between the available space and the contents within the fetlock tunnel. The main symptoms are a persisting lameness, distention of the tendon sheath, a typical "notch" when the fetlock is viewed from the side and a hyperflexion pain in the fetlock. The surgical treatment consists of the transection of the fetlock annular ligament. The conservative management can be considered as a independent therapy or as a preparation for a subsequent desmotomy. The medical records of 75 horses suffering from fetlock tunnel syndrome presen...
Kagawa S, Moore JE, Murayama O, Matsuda M.Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzym...
Kruttlin EA, Rossano MG, Murphy AJ, Vrable RA, Kaneene JB, Schott HC, Mansfield LS.Sarcocystis neurona is the etiologic agent of equine protozoal myeloencephalitis, a neurologic disease of horses. The present study was designed to test the hypothesis that pyrantel tartrate can kill S. neurona merozoites growing in equine dermal cell culture. Sarcocystis neurona merozoites were exposed to a range of concentrations of pyrantel tartrate or sodium tartrate ranging from 0.001 to 0.01 M. Merozoites were then placed onto equine dermal cell cultures and incubated for 2 weeks to check for viability. At 1 and 2 weeks after inoculation, plaque counts were compared between treatments an...
Furr M, Kennedy T.Ponazuril was administered orally to 10 adult horses at 5 mg/kg body weight, once a day for 28 days. Blood was collected once a week from each horse from Days 0 through 35, daily from Days 35 through 42, and on Day 49. Cerebrospinal fluid (CSF) was also collected once a week from Day 0 through Day 49. Concentrations of ponazuril in the serum and CSF were determined, and pharmacokinetic calculations were performed. Ponazuril was readily absorbed following oral administration; and after 7 days of dosing, the serum concentration was 4.33 +/- 1.10 mg/L, and the mean CSF concentration was 0.162 +/-...
Stout TA, Allen WR.Between at least day 9 and day 16 after ovulation the spherical equine conceptus migrates continuously throughout the uterine lumen, propelled by peristaltic myometrial contractions. This unusually long period of intrauterine movement ensures that the conceptus delivers its anti-luteolytic signal to the entire endometrium to achieve luteostasis. The present experiment tested the hypothesis that prostaglandins stimulate the myometrial contractions that result in the migration of the conceptus. Serial ultrasonographic examinations of the uteri of eight mares performed during 2 h periods between ...
Ellis JA, Konoby C, West KH, Allan GM, Krakowka S, McNeilly F, Meehan B, Walker I.Porcine circovirus type 2 (PCV2) is a recently recognized agent that is consistently associated with postweaning multisystemic wasting disease in swine. There are conflicting data concerning the ability of this virus to infect and cause disease in other species. To determine if normal cattle, cattle affected with various illnesses, and normal horses in endemic areas of PCV2 infection in swine have had PCV2 infections, 100 randomly selected bovine sera, 100 equine sera, and 100 colostrum samples from clinically normal dairy cattle were examined for the presence of antibodies to porcine circovir...
Ozaki H, Sugiura T, Sugita S, Imagawa H, Kida H.Antibodies to the nonstructural protein (NS1) of A/equine/Miami/1/63 (H3N8) influenza virus were detected exclusively in the sera of mice experimentally infected with A/Aichi/2/68 (H3N2) and horses infected with A/equine/Kentucky/1/81 (H3N8) or A/equine/La Plata/1/93 (H3N8), but not in those of the animals immunized with the inactivated viruses, by enzyme-linked immunosorbent assay (ELISA) using a recombinant NS1 as antigen. The results indicate that the present method is useful for serological diagnosis to distinguish horses infected with equine H3 influenza viruses from those immunized with ...
Shubitowski DM, Venta PJ, Douglass CL, Zhou RX, Ewart SL.The continued discovery of polymorphisms in the equine genome will be important for future studies using genomic screens and fine mapping for the identification of disease genes. Segments of 50 equine genes were examined for variability in 10 different horse breeds using a pool-and-sequence method. We identified 11 single nucleotide polymorphisms (SNPs) in 9380 bp of sequenced exon, and 25 SNPs, six microsatellites, and one insertion/deletion in 16961 bp of sequenced intron. Of all genes studied 52% contained at least one polymorphism, and polymorphisms were found at an overall rate of 1/613 b...
Klei TR, Rehbein S, Visser M, Langholff WK, Chapman MR, French DD, Hanson P.Two trials were conducted to confirm the efficacy of ivermectin paste against endoparasites of horses. In these trials, 20 ponies were treated with ivermectin oral paste at 200 mcg x kg body weight once on Day 0, and 20 ponies served as unmedicated controls. The animals carried naturally acquired parasite infections as confirmed by pretrial fecal examination. The animals were necropsied for worm recovery on Days 14, 15 or 16. Parasites recovered were identified to species. Horses treated with ivermectin had significantly (P99.0% reduction) adult small strongyles (Coronocyclus spp including C. ...
Terry RR, Bailey E, Bernoco D, Cothran EG.The appaloosa coat colour pattern of the horse is similar to that caused by the rump-white (Rw) gene in the mouse. In the mouse Rw colour pattern is the result of an inversion involving the proto-oncogene c-kit (KIT). Therefore, we investigated KIT as a candidate gene that encodes the appaloosa coat colour gene (Lp) in horses. KIT plays a critical role in haematopoiesis, gametogenesis, and melanogenesis and encodes a transmembrane tyrosine kinase receptor that belongs to the PDGF/CSF-1/c-KIT receptor subfamily. Half-sib families segregating for Lp were uninformative for a reported polymorphism...
Secchi C, Berrini A, Gaggioli D, Borromeo V.Modified amino acid residues in porcine, canine and equine growth hormones purified from pituitary glands were characterised by tryptic mapping and high-performance liquid chromatography with on-line coupled electrospray ionisation mass spectrometry (HPLC-ESI-MS) detection. Hormones from all three species showed the same changes. Conversion of Asp128 to iso-Asp128 was a component of native hormones, while deamidation of Asn12 and Asn98 to Asp and iso-Asp, oxidation of Met4, and cyclisation to the pyroglutamyl derivative of Gln139, probably occurred in vitro, during isolation, storage or hydrol...
Tarigo-Martinie JL, Wyatt AR, Kaplan RM.To determine the prevalence and clinical implications of anthelmintic resistance in cyathostomes of horses. Methods: Prospective study. Methods: 80 horses on 10 farms in a 5-county region of northeast Georgia. Methods: On each farm, horses were stratified in descending order according to pretreatment fecal egg count (FEC), blocked into groups of 4, and then randomly assigned to 1 of 4 treatment groups: no treatment (controls), and treatment with pyrantel pamoate, fenbendazole, or ivermectin. Fecal samples were collected 24 hours prior to treatment and 2, 4, and 6 weeks after treatment for dete...
Hauser B, Wehrend A, Bostedt H, Failing K.Analysis of blood gases in equine neonatology is regarded as a diagnostic tool to study the neonatal adaptation period. Aim of this study therefore was to compare the diagnostic value of venous blood gas parameters to arterial parameters in newborn foals with pulmonary disorders. Venous as well as arterial blood samples were taken from 24 foals (1 to 6 days old) and the partial pressure of oxygen (pO2), partial pressure of carbon dioxide (pCO2), pH, and oxygen parturition (S-O2) of these samples were investigated. In addition, the alveolar (A) to arterial (a) gradients (A-aDO2) were calculated...
Troedsson MH, Ababneh MM, Ohlgren AF, Madill S, Vetscher N, Gregas M.The objective of this study was to determine whether periovulatory treatments with PGF2alpha affects the development of the CL, and whether the treatment was detrimental to the establishment of pregnancy. Reproductively sound mares were assigned randomly to one of the following treatment groups during consecutive estrus cycles: 1. 3,000 IU hCG within 24 hours before artificial insemination and 500 microg cloprostenol (PGF2alpha analogue) on Days 0, 1, and 2 after ovulation (n=8), 2. 2 mL sterile water injection within 24 hours before artificial insemination and 500 microg cloprostenol on Days ...
Rupić V, Bacar-Huskić L, Lojkić M, Habe F, Ergotić N.Research was carried out into the effect that different quantities and compositions of concentrated portions of meal had on certain haematological properties and on the immune response of mares in the course of hyper-immune antitetanus sera production. The experiment involved 24 Nonius and Lipizzaner cross-bred mares divided into two groups of 12 animals each, a control group and a trial group. The experiment lasted 12 months, with haematological and immunological tests being carried out every 30 days. During the course of the experiment each mare was subjected to 11 immunisation cycles, and i...
Brama PA, Barneveld A, Karssenberg D, Van Kampen GP, van Weeren PR.A recently developed indenter system that aims at determination of local structural properties of the cartilage surface was evaluated for suitability in the horse. To this aim, maximum indenter force was measured of the articular surface and related to biochemical characteristics of the cartilage at different sites of the distal metacarpal bone (MC). Significant topographical variation exists in structural properties of the articular surface of the MC. The dorsal margin showed a significantly lower maximum indenter force than more centrally located areas, indicating an increased compliance und...
Malikides N, Hodgson JL, Rose RJ, Hodgson DR.To determine whether removal of 20 mL/kg of blood (approximately 25% of blood volume) resulted in adverse physiological effects in donor horses, we removed this volume of blood from five horses and selected cardiovascular, haematological and biochemical variables measured during collection and for 31 days thereafter. We found that alteration in most variables occurred, although the changes in values usually remained within published reference ranges. Also, recovery of these alterations to pre-collection values was rapid, occurring within 24--48 h in most instances. We concluded that volumes of...
Ohmura H, Hiraga A, Aida H, Takahashi T, Nukada T.To determine oral dosage and to evaluate the pharmacokinetics in horses of orally administered flecainide, an antiarrhythmic drug, the correlations between its plasma concentration and PR, QRS and QT intervals in equine electrocardiograms (ECG) were investigated. Six healthy horses were administered a randomly ordered dose of 4 or 6 mg/kg of flecainide acetate. The ECG was monitored (heart rate (HR), PR, QRS, and QT intervals) and blood was taken at timed intervals to measure the plasma flecainide concentrations pre- and post-administration. The maximum plasma concentration reached 1014+/-285 ...
Damron GW.A survey of horses for gastrointestinal trichomonads was conducted to determine the organism's role in equine diarrhea and to establish its proper identity and morphology. Trichomonads were found by cultural examination of feces of 101 (35%) of 289 apparently healthy horses. At necropsy, trichomonads were cultured from 11 (37%) of another 30 horses which showed no signs of diarrhea at the time of death. In 4 of the 11 horses, colonies of trichomonads numbered 30,000 to 150,000/ml of cecal fluid. Diarrhea was induced in 1 of 6 horses, with the fecal fluid containing 10,000 to 110,000 trichomona...
Kingston JK, Bayly WM, Meyers KM, Sellon DC, Wardrop KJ.There is evidence that equine platelet reactivity is altered by strenuous exercise. Changes in platelet reactivity could impact haemostasis following exercise-induced injury and may play a role in the pathophysiology of exercise-induced pulmonary haemorrhage. Interpretation of results of previous studies is hindered by potential in vitro-induced changes in platelet activity through the choice of anticoagulant and the use of platelet inhibitors. The present study was undertaken to re-evaluate the effect of exercise on equine platelets using methodologies that minimise in vitro-induced changes i...
Zakin MM, Peña C, Poskus E, Stewart JM, Paladini AC.The immunological properties of a synthetic human growth hormone fragment comprising the amino acids 73 through 128 and of the homologous natural horse growth fragment formed by amino acids 73 through 123, have been comparatively studied. Antisera obtained in rabbits inoculated with the native human hormone or with the fragments, were used. By hemagglutination experiments both fragments have the same reactivity toward the anti-human growth hormone serum, but complement fixation curves detect the existence of at least two populations of antibodies presumably originated against the sequence 73-1...
Buchner HH, Savelberg HH, Becker CK.An analysis of joint moments was used to study the biomechanical implications, load redistribution and kinematic pattern following desmotomy of the accessory ligament of the deep digital flexor tendon (AL) in adult horses. Recordings of 6 sound horses were made before and 10 days after desmotomy of the AL of the right forelimb at the walk and the trot. Kinematic recordings of the right forelimb and the left distal forelimb were made using the CODA-3 system. Kinetic recordings of the ground reaction forces in both forelimbs were made using a Kistler force plate simultaneously with the kinematic...
Chu JW, Sharom FJ, Oriol JG, Betteridge KJ, Cleaver BD, Sharp DC.The equine embryonic capsule, an acellular covering that envelops the conceptus during the second and third weeks of pregnancy, is composed of mucin-like glycoproteins. Its structure is consistent with a dual role during early pregnancy: protection of the conceptus, and communication between the embryo and the mother. Loss of sialic acid from the capsular glycoproteins at day 16 correlates with the time of "fixation," or loss of conceptus mobility throughout the uterine horns. This study investigated how the structure of the capsule is linked to the maintenance of pregnancy. Six pregnancies, c...
Pusterla N, Miller J, Varnell S, Armstrong W, Frost L, Michon C, Lambert K, Whitfield S, Cowles B.The objective of this study was to study the SAA response of horses with various forms of EHV-1 infection. Archived serum samples from 153 horses with various disease forms of EHV-1 infection (48 healthy non-infected horses, 48 subclinically infected horses, 40 horses with respiratory EHV-1 infection and 17 horses with neurological EHV-1 infection) were available for SAA testing. SAA values ranged from 0 to 31 µg/mL (median 0 µg/mL) in healthy horses, from 0 to 2,416 µg/mL (median 8.5 µg/mL) in subclinically infected horses, from 0 to 3,000 µg/mL (median 597 µg/mL) in horse with respirat...
Boakari YL, Esteller-Vico A, Loux S, El-Sheikh Ali H, Fernandes CB, Dini P, Scoggin KE, Cray C, Ball BA.Serum amyloid A (SAA) and Haptoglobin (Hp) are acute phase proteins, produced during inflammation, such as placentitis. In horses, SAA and SAA1 are protein coding genes. Objectives were to analyze SAA and Hp concentrations and relative abundance of SAA, SAA1 and Hp mRNA transcript in maternal and fetal tissues after experimental induction of placentitis or mares of a control group. Serum Amyloid A family proteins were in marked abundance in the stroma of the endometrium and chorioallantois associated with inflammatory cells. Maternal plasma SAA concentrations were greater (P = 0.01) in mares w...
Pérez-Marín CC, Vizuete G, Borge C, Galisteo JJ.While testing for uterine bacterial infection is usually performed prior to artificial insemination (AI), samples taken during or after embryo flushing are generally not assessed either in subfertile and old mares or in fertile mares, even though knowledge of the status of the uterine environment in which the embryo is to develop would help to predict the outcome of embryo transfer programmes. The presence of bacteria and inflammatory cells in the liquid retained in the filter after uterine flushing in donors was determined at the moment of embryo recovery. Primarily, a group of mares (n = 8) ...
Santos MP, Gutierrez-Nibeyro SD, Horn GP, Hicke JD, Stewart MC, Schaeffer DJ.To compare the mechanical properties of laryngeal tie-forward (LTF) constructs prepared with different suture materials and suture placement patterns during single load to failure testing. Methods: Larynges harvested from 50 horse cadavers and 5 intact horse cadavers. Methods: In vitro LTF constructs were created by a standard technique with polyester sutures, a standard technique with polyethylene sutures, a modified technique with metallic implants and polyester sutures, a modified technique with metallic implants and polyethylene sutures, or a modified tie-off technique with polyester sutur...