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.
Nation PN.Over sixteen years, 49 horses were diagnosed by Alberta Agriculture Animal Health laboratories as having "alsike clover poisoning". There was a distinct northwestern distribution of cases, the majority coming from the Peace River district. This distribution is opposite to that of the Alberta horse population, but coincides with areas of alsike clover cultivation. Cases could be divided into chronic or nervous clinical presentations, as described by Schofield. Tissues from 45 animals were retrieved and examined microscopically. Significant histological lesions were confined to the liver and con...
Burba DJ, Collier MA.A 5-hole T-plate was used to repair an unstable compound depression fracture of the nasal bones in a horse. Substantial bone loss was evident as a result of severe trauma. Satisfactory bone healing, facial contour, and airway function were achieved. The use of a T-plate can be an alternative means of repair of a nasal bone fracture in a situation in which instability and/or bone loss exists.
Houpt KA.Some of the techniques that may be used to study social, reproductive, and ingestive behavior in horses are described in this paper. One of the aspects of equine social behavior is the dominance hierarchy or patterns of agonistic behavior. Paired or group feeding from a single food source may be used to determine dominance hierarchies quickly. Focal animal studies of undisturbed groups of horses may also be used; this method takes longer, but may reveal affiliative as well as agonistic relationships among the horses. Reproductive behavior includes flehmen, the functional significance of which ...
Davis SW, Speer CA, Dubey JP.Asexual stages of Sarcocystis neurona were seen in cultured bovine monocytes (M617) inoculated with tissue homogenates from the spinal cord of a horse with naturally acquired protozoal myelitis. Organisms first were observed as intracytoplasmic schizonts and later as motile extracellular zoites capable of infecting surrounding M617 cells. Parasites most often occurred as clusters of merozoites dispersed throughout the host cell cytoplasm; however, schizonts also contained merozoites arranged in a radial fashion surrounding a prominent residual body. Schizonts divided by endopolygeny. The paras...
Kroneman J.The clinical importance of the AV blocks in horses discussed. The second degree AV block is a symptom of the adaptation of the heart to increased workload and it is not an indication of a good performance.
Moon PF, Snyder JR, Haskins SC, Perron PR, Kramer GC.Conventional fluid resuscitation is unsatisfactory in a small percentage of equine emergency surgical cases because the large volumes of fluids required cannot be given rapidly enough to adequately stabilize the horse. In anesthetized horses, the volume expansion and cardiopulmonary effects of a small volume of highly concentrated hypertonic saline-dextran solution were evaluated as an alternative initial fluid choice. Seven halothane-anesthetized, laterally recumbent, spontaneously ventilating, normovolemic horses were treated with a 25% NaCl-24% dextran 70 solution (HSD) at a dosage of 1.0 m...
Harrison IW.Excisional biopsy of a skin lesion was performed in 4 horses after stretching the surrounding skin with mattress sutures. The technique of presuturing allowed all biopsy wounds to be closed without excessive tension on the suture lines.
Meyer H.Colics are often initiated by mistakes in feeding inadequate feed quality or quantity or poor feeding technique. The consequences are obstruction, impaction or dysbiosis with increased production of organic acids, gas or toxins. Nutritional anamnesis in patients with colic may give information on the pathogenesis of the disease.
Cargile J, Lombard C, Wilson JH, Buergelt CD.A 3-year-old Morgan filly was presented to the University of Florida, Veterinary Medical Teaching Hospital, for heart murmur, poor growth, and progressive exercise intolerance. Thoracic radiographs, cardiac ultrasound, cardiac catheterization, and differential blood gases were utilized to tentatively diagnose tetralogy of Fallot. Postmortem examination confirmed tetralogy of Fallot and additionally revealed segmental uterine aplasia.
Proudman CJ, Knottenbelt DC, May SA, Edwards GB.Several imaging techniques were used to diagnose hypoplasia of the soft palate in a horse. The absence of the caudal soft palate, hypertrophied lymphoid tissue and the formation of a pseudouvula were observed endoscopically. Plain and contrast radiography were used to demonstrate a soft palate remnant and to identify structures rostral to the epiglottis. Retrograde endoscopy of the pharynx via a tracheotomy incision is described.
McDonnell SM, Pozor MA, Beech J, Sweeney RW.A 9-year-old atactic breeding stallion was trained to ejaculate, with only manual stimulation, while standing on the ground. Ejaculates obtained yielded fertile semen with morphologic and motility characteristics within the range for normal stallions. This method extended the breeding life of a stallion unable to mount a live or dummy mare or to ejaculate into an artificial vagina while standing on the ground.
Kinde H, Bettey RL, Ardans A, Galey FD, Daft BM, Walker RL, Eklund MW, Byrd JW.An episode of nervous system dysfunction was observed in horses on 17 premises in 4 counties of southern California. Thirty-eight horses were affected, and 31 of those died. The common clinical signs of disease in the affected horses were: increased appetite; anxious attitude; rythmic, intermittent muscle tremors in the area of the tricep muscles; decreased palpebral tone; mydriasis; small hard fecal balls; and tendency to become sternally recumbent with the neck extended. The temporal distribution of cases on all 17 premises suggested a relationship between exposure to a common batch of alfal...
Cohen ND, Carter GK.Persistent thrombocytopenia was detected in a horse with equine infectious anemia (EIA). The thrombocytopenia was considered to be immune-mediated, developing secondary to infection with EIA virus. Epistaxis, petechial hemorrhages, subcutaneous hematomas, and edema resolved after treatment with corticosteroids; however, the owners requested that the mare by euthanatized because of infection with EIA virus. Although clinical signs attributable to immune-mediated thrombocytopenia may resolve with appropriate treatment, horses with immune-mediated thrombocytopenia secondary to EIA have a guarded ...
Kadir FH, al-Massad FK, Fatemi SJ, Singh HK, Wilson MT, Moore GR.Reactions of reduced horse spleen ferritin with horse and Saccharomyces cerevisiae ferricytochromes c, cow ferricytochrome b5, sperm-whale metmyoglobin and Pseudomonas aeruginosa ferricytochrome c-551 were investigated by u.v.-visible spectrophotometry. In all cases the reduced ferritin reduced the ferrihaemoproteins. The rate of reduction varied from less than 0.2 M-1.s-1 for metmyoglobin to 1.1 x 10(3) M-1.s-1 for horse ferricytochrome c (0.1 M-phosphate buffer, pH 7.4, at 25 degrees C). We conclude that the mechanism of ferrihaemoprotein reduction involves long-range electron transfer throu...
Whitehair KJ, Parker JE, Smith GN, Adams SB, Bottoms GB.Serum levels of type III procollagen peptide (P-III-P) were measured by radioimmunoassay in clinically normal adult ponies (n = 15) and horses (n = 10). The mean serum levels of P-III-P from the ponies, 10.4 +/- 2.9 (SD) ng/mL, and the horses, 12.2 +/- 2.6 (SD) ng/mL, were not significantly different. Segments of jejunum were made ischemic to induce fibrous peritoneal adhesions in two ponies, and serum P-III-P levels were measured on days 4, 5, 7, 14, and 21. An exploratory celiotomy on day 21 revealed that the ischemic injury had induced fibrosis of the mesentery and bowel, but no adhesions h...
Wisner ER, O'Brien TR, Pool RR, Pascoe JR, Koblick PD, Hornoff WJ, Poulos PW.Destructive lesions of the axial region of the proximal sesamoid bones were identified by radiography in eight fetlocks and seven lame adult horses. Lameness ranged from 2 to 5 (mean 4; scale 1 to 5) at the time of examination, with a duration of 10 days to two years (mean 5.6 months). Destructive lesions involved both proximal sesamoid bones when examined radiographically and were situated primarily at the level of the mid-body and apical region of the axial borders. Some lesions were cystic, whereas others eroded the axial border more diffusely. Scintigraphy revealed markedly increased activ...
Sarazan RD, Krause GF, Franklin D, Garner HE, Griggs DM.Coronary reactive hyperemia duration (RHD) and coronary blood flow debt repayment (BFDR) were compared in conscious dogs and ponies instrumented with coronary artery Doppler flow probes and pneumatic occluders. Additional ponies were instrumented with pacing electrodes. With the use of a Latin square design, eight animals of each species were subjected to a randomized series of nine coronary occlusions ranging from 5 s to 2 min in duration. In both species, postocclusion blood flow velocity rose rapidly and plateaued at similar peak levels relative to control, but in ponies this plateau lasted...
Colborn DR, Thompson DL, Rahmanian MS, Roth TL.Ten lighthorse stallions were used to determine 1) whether prolactin (PRL) and cortisol responses previously observed after acute exercise in summer would occur in winter when PRL secretion is normally low, 2) whether subsequent treatment with a dopamine receptor antagonist, sulpiride, for 14 d would increase PRL secretion and response to thyrotropin-releasing hormone (TRH) and exercise, and 3) whether secretion of LH, FSH, and cortisol would be affected by sulpiride treatment. On January 11, blood samples were drawn from all stallions before and after a 5-min period of strenuous running. On J...
Willham RL, Wilson DE.Research on the racing performance of quarter horses has been used to develop genetic prediction summaries on all horses with at least one start on record at the American Quarter Horse Association. In the 1987 summary, records from a total of 212,065 horses were used to give genetic predictions on stallions, mares, geldings, fillies, and colts. A reduced animal model was used that incorporated the repeated records of individuals. The individual race was the contemporary group after the data were adjusted for distance, sex, and age. Estimates of heritability of .24 and repeatability of .32 sugg...
Foley GL, Valentine BA, Kincaid AL.In a retrospective study, cutaneous melanocytic tumors from 18 horses, less than 2 years old, were examined histopathologically and clinical follow-up requested. Melanocytomas (benign melanomas) occurred in a variety of breeds and in horses of varied coat color. The age of the horses at the time of biopsy ranged from 3 weeks old to 2 years old. Four melanocytomas were congenital, 11 melanocytomas were acquired by 1 year of age, and three were acquired prior to 2 years of age. Of the 18 horses, five were male, and 13 were female. All tumors were solitary and located on the legs or trunk; none w...
McCoy HE, Broder CC, Lottenberg R.The species specificities of plasminogen activation and binding of plasmin by pathogenic group C streptococci isolated from humans, horses, and pigs were examined. Of 56 streptococcal isolates, 52 elaborated plasminogen activator activity and 49 of these had specificity for plasminogen of the homologous host. Analysis of supernatants from 13 isolates indicated that the plasminogen activator activity resulted from secreted streptokinases. These 13 streptokinases were antigenically related and bound all three plasminogens, indicating that the binding recognition sites were conserved despite the ...
Frietsch G, Weigand E, Prüstel N.The postnatal iron status of 20 trotter foals (7 female, 13 male) was studied by analyzing different parameters in blood drawn on the day of birth, and 14 +/- 2 and 28 +/- 2 days later. Hemoglobin hematocrit, plasma iron and transferrin saturation averaged 14.9 g/dl, 41.8%, 300 micrograms/dl and 59.4%, respectively, on the day of birth. These values were significantly reduced after 14 days, but had approached again the initial levels by day 28. There was a slight, statistically nonsignificant rise in the mean total iron-binding capacity over the four-week period. Iron status was not affecting ...
Krivolutskiĭ DA, Nguyen TK, Fan TV.101 species of oribatid mites and 12 species of helminths--anoplocephalids, transmitted by these mites, were found out by Soviet-Vietnam studies in agroecosystems and tropical forests of northern and southern Vietnam. Helminths were recorded from graminivorous mammals as follows: horses, zebu, sheep, goats, buffaloes, deer, hares, elephant, 2 species of rates, 5 species of monkeys and 11 species of birds.
Francis JM, Neander CR, Roeder MJ, Perry EB.Palatants may be added to equine feed and medication either during or after manufacturing to enhance product acceptance. Prior studies have examined a variety of palatants but results have been limited and inconsistent. Therefore, the objective of this research was to evaluate topically applied oil-based palatants on feeding preferences in horses. Stock-type horses (n = 10) were used in this paired preference test across a two-phase study. Phase one compared six palatants (banana, anise, peppermint, apple, spearmint, and orange) to a control (corn oil), whereas phase two compared preference a...
Quinn GC, Tremaine WH, Lane JG.There are few reports of case series of horses with supernumerary cheek teeth (SCT) that document clinical findings, treatment and long-term outcome. Objective: To review the clinical and ancillary diagnostic findings and responses to different treatments in horses with SCT. Methods: The case records of 15 horses were reviewed and long-term outcomes obtained by telephone interview. Results: Fifteen horses with a total of 24 SCT were identified. Two SCT were incidental findings and were not treated. Clinical signs were improved or resolved in 11 of 13 of the teeth treated conservatively and all...
Martens A, de Moor A, Waelkens E, Merlevede W, De Witte P.The therapeutic potential of the photodynamic compound, hypericin, in the treatment of equine sarcoids was evaluated. The in vitro cytotoxicity was assessed using three equine cell lines and the observed phototoxic effect was comparable to that on different highly sensitive human cell lines and significantly influenced by the energy density used although independent of the cell type. The in vivo antitumoural action of photodynamic therapy using hypericin was evaluated on three equine sarcoids in a donkey. Four intratumoural injections were given and the tumours were illuminated daily during 25...
Eckers C, Skrabalak DS, Henion J.We describe an integrated micro-liquid chromatograph/mass spectrometer (micro-LC/MS) system capable of performing routine determinations for 1--10 ng of drugs and their metabolites extracted from biological fluids. The micro-LC is constructed from conventional "high-performance" liquid-chromatographic instrumentation by using commercially available components. The mass spectrometer is operated in the chemical ionization mode. The direct liquid introduction micro-LC/MS interface can be constructed from commercially available materials. Chromatographic and mass spectral results demonstrate the a...
Reimann HA.It is conceivable that a change from the virulent, non-phagocytable S form of Pneumococcus to the avirulent phagocytable R form may take place in pneumococcus disease, but the experiments here reported do not settle the question whether or not this is an important factor in determining the outcome in natural infection. It has been shown experimentally that the degradation from the S form to the R form actually does take place in cultures of Pneumococcus growing in agar subcutaneously embedded in guinea pigs, in agar enclosed in vials subcutaneously embedded in rabbits, and spontaneously in the...
Li JR, Wang W, Shi FX.The effects of equine chorionic gonadotropin (eCG) on follicular development and ovulation in cyclic guinea pigs were investigated by histological and immunohistochemical analyses. Three groups of guinea pigs (n=12) were administrated subcutaneously with saline, 20 or 50 IU of eCG, respectively, on cyclic Day 12 (Day 1=vaginal openings). Ovaries were collected at 4 and 8 d after administration (6 animals per group each time). The eCG administration induced significant and distinct morphological changes in the ovaries, as it promoted the luteinization of granulosa cells, but not follicular deve...
Jemmerson R, Margoliash E.Of the antigenic determinants so far identified for cytochrome c, only one involves more than a single amino acid substitution between the immunogen and host proteins. Both a threonine at position 89 and a glutamic acid at position 92 control one of the three antigenic sites identified in horse cytochrome c, as expressed in rabbits. Three antibody subpopulations, all directed against this region of the molecule, were isolated from the serum of a single rabbit by adsorption on a series of insolubilized cytochromes c. Antibody fluorescence quenching titrations with a variety of cytochromes c wer...
Wang Z, Robinson NE, Yu M.This study was conducted to determine the effects of stimulation parameters and muscle preload on acetylcholine (ACh) release induced by electrical field stimulation (EFS) of horse airway cholinergic nerves. Trachealis strip bundles were prepared and suspended in 2-ml tissue baths. The tissues were stimulated three to five times for 30 min each. Increasing frequency (0.5-16 Hz) and voltage (5-20 V) increased ACh release; increasing pulse duration (0.5-3 ms) had only a minor effect. Alterations in muscle preload (2-20 g) had no effect on ACh release. ACh release was fairly constant for up to fi...
Betton JM, Desmadril M, Mitraki A, Yon JM.The unfolding-refolding transition of horse muscle phosphoglycerate kinase induced by guanidine hydrochloride was studied under equilibrium conditions using four different signals: fluorescence intensity at 336 nm, UV difference absorbance at 286 and 292 nm, ellipticity at 220 nm, and enzyme activity. From the following arguments, we found that the process deviates from a two-state model and intermediates are significantly populated even at equilibrium: (1) the noncoincidence of the transition curves and (2) the asymmetry of the transition curve obtained from CD measurements. From these differ...
Gerber H, Ueltschi G, Diehl M, Schatzmann U, Straub R.For various anamnestic reasons the cervical vertebral column of 78 horses was examined radiologically. Statistical comparisons showed that male "warmbloods" were more frequently affected than was expected. Our horses were older than comparable animals in the international literature. Independently of their history the radiologic diagnosis of "cervical spondylarthrosis" was established in 56 horses. Arthrosis and other conditions were clinically manifested by spinal ataxia (44 horses) or mechanical impairment of the neck's mobility (21 horses). 10 of the arthrotic patients had synovial cysts ca...
Bauerfeind R, Barth S, Weiss R, Baljer G.Strains of Salmonella isolated from animals in Germany (n = 878) were analysed for the presence of the spvD gene ("Salmonella plasmid virulence gene D") by DNA-DNA hybridization. The spvD gene was only detected in strains of serovars Typhimurium (93.3%), Enteritidis (97.1%), and Dublin (100%) as well as in two rough strains of Salmonella enterica. Salmonella isolates from mammals carried the gene more frequently (cattle 94.0%, horses 92.6%, pigs 73.7%) than those from birds (33.3%) or reptiles (4.5%). Due to its high prevalence in epidemiologically relevant salmonellae, the virulence factor sp...
Laing JA, Hutchins DR.Progressive ethmoidal haematoma was diagnosed in 12 Thoroughbreds, 1 part- Arab and 1 stock horse. Ages ranged from 3 to 18 years and both males and females were affected. Diagnosis was based on history, clinical signs, endoscopic and radiographic findings, and was confirmed histologically in 10 cases. Eleven (78%) of the lesions were unilateral and 3 (22%) were bilateral. Two horses were euthanased on diagnosis, 4 were treated conservatively. Of the latter, 3 were euthanased 6 to 24 months after diagnosis, due to progression of the lesions, while 1 case resolved completely within 13 months. E...
Padilla SL, Prieto K, Dohm DJ, Turell MJ, Klein TA, Fernández R, Watts DM, Lowen RG, Palacios GF, Pitt ML, Wiley MR, Nasar F.Venezuelan equine encephalitis virus (VEEV) is an important pathogen of medical and veterinary importance in the Americas. In this report, we present the complete genome sequences of five VEEV isolates obtained from pools of Culex (Melanoconion) gnomatos (4) or Culex (Melanoconion) pedroi (1) from Iquitos, Peru. Genetic and phylogenetic analyses showed that all five isolates grouped within the VEEV complex sister to VEEV IIIC and are members of subtype IIID. This is the first report of full-length genomic sequences of VEEV IIID.
Westendorf J, Wobeser B, Epp T.Inter- and intra-rater variability negatively affects the reliability of various histopathology grading scales used as prognostic aids in human and veterinary medicine. The Kenney-Doig categorization (grading) scale, which is used to associate equine endometrial histologic lesions with prognostic estimation of a broodmare's reproductive potential, has not been evaluated for inter- or intra-rater variability, to our knowledge. To assess whether the Kenney-Doig system produces reliable results among observers, 8 pathologists, all with American College of Veterinary Pathologists certification, we...
Woods GL, Steiner JV.The objective of this project was to produce multiple pregnant recipient mares during one year from each of four mares which were in athletic training and competition. Twenty-six embryos were recovered from the four mares in 38 collection attempts. Each embryo was surgically transferred to one of 20 recipient mares. Nine of 10 recipient mares which were transferred to on one occasion were detected pregnant at the one week post transfer pregnancy examination and six of eight mares which were transferred to on two occasions were detected pregnant at one of the one-week post transfer pregnancy ex...
Awasthi G, Srivastava G, Das A.Comparative genomics and evolutionary analyses of conserved genes have enabled us to understand the complexity of genomes of closely related species. For example: β-globin gene present in human hemoglobin is one such gene that has experienced many genetic changes in many related taxa and produced more than 600 variants. One of the variant, HBS causes sickle-cell anemia in humans but offers protection against severe malaria due to Plasmodium falciparum. In the present study, we characterized and performed evolutionary comparative analyses of the ?-globin gene in different related and unrelated...
Heerkens TM.Equine herpesvirus 1 (EHV-1) causes rhinopneumonitis, abortion, and rarely, myeloencephalopathy. The neurovirulence of this virus is due to a point mutation in the DNA polymerase gene. Diagnosis by virus isolation has been replaced by real-time polymerase chain reaction (RT-PCR) assays that can detect strains, viral loads, and states; this may aid in control and management of the disease. L’herpèsvirus équin de type-1 (EHV-1) cause la rhinopneumonie, l’avortement et rarement la myéloencéphalopathie. La neurovirulence de ce virus est attribuable à une mutation ponctuelle à l’intér...
Evans DL, Silverman EB, Hodgson DR, Eaton MD, Rose RJ.The relationship between gait and the respiratory response to exercise was examined in five standardbred racehorses which exercised on a treadmill at a pace and a gallop. After an initial warm-up, respiratory rate and stride frequency were measured after one and two minutes of treadmill exercise at 80 per cent of maximal oxygen consumption (VO2max), after one minute at 100 per cent VO2max and after two minutes at 100 per cent VO2max (galloping horses only). Exercise at 100 per cent VO2max continued until the horses showed signs of fatigue. Arterial blood was collected during exercise and when ...
Teijeiro JM, Marini PE.The oviduct is a dynamic organ in which final gamete maturation, fertilization and early embryo development take place. It is considered to be a sterile site; however the mechanism for sterility maintenance is still unknown. S100A7 is an anti-microbial peptide that has been reported in human reproductive tissues such as prostate, testicle, ovary, normal cervical epithelium and sperm. The current work reports the presence of S100A7 in the Fallopian tube and its localization at the apical surface of epithelial cells. For comparison, porcine S100A7 was used for antibody development and search for...
Jonckheere JA, Thienpont LM, De Leenheer AP, De Backer P, Debackere M, Belpaire FM.A method has been developed for quantification of bromhexine in plasma using gas chromatography mass spectrometry with selected ion monitoring. A deuterium labelled analogue was synthesized and used as the internal standard. To evaluate the gas chromatographic electron capture detection method described earlier, 23 plasma samples have been analysed by both techniques. Although a good correlation was shown, selected ion monitoring was superior to the electron capture detection method for levels below 3 ng ml-1. The mass spectrometric method has also been used to set up a pharmacokinetic study o...
Katzman SA, Spriet M, Galuppo LD.OBJECTIVE To describe the use of CT in the diagnosis of and presurgical planning for equids with keratomas treated by hoof wall resection and determine postoperative complications and outcome. DESIGN Retrospective case series. ANIMALS 29 horses and 3 mules with keratomas treated by partial or complete hoof wall resection following CT imaging of the distal portion of the affected extremity from 2005 through 2016. PROCEDURES For each equid, physical examination and lameness evaluation were performed, followed by imaging of the distal portion of the affected extremity. A tentative diagnosis of ke...
