"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Shiroma JT, Engel HN, Wagner PC, Watrous BJ.In horses, dorsal subluxation of the proximal interphalangeal joint in the pelvic limb, which realigned when weight was applied to the limb, improved following surgery. Improvement was observed, if not immediately, at least within two weeks after treatment. The severity and duration of the condition appear to be important considerations in predicting the time necessary for resolution of the condition following surgery. Treatment consisted of surgical resection of a small segment of the medial head of the deep digital flexor tendon in the pelvic limb. The section removed was positioned distal t...
Smith BL, Morton LD, Watkins JP, Taylor TS, Storts RW.A 16-year-old cryptorchid Quarter House with colic had a large, lobulated soft-tissue mass to the left of the pelvic inlet. At surgery, 2 large multilobulated pedunculated masses were removed. A large blood vessel enveloped by one of the masses was damaged, and the horse exsanguinated. Postmortem examination of the abdomen revealed the masses to be malignant seminoma, with multiple sites of metastasis.
Bukowiecki CF, van Ee RT, Schneiter HL.A comminuted scapular fracture in a foal was treated surgically by use of 2 dynamic compression plates. The plates were applied upside down, so that the convex surface of the plate faced the bone. At 5 months after surgery, the plates were removed, and the foal recovered without complications.
Snyder JR, Pascoe JR, Olander HJ, Spier SJ, Meagher DM, Bleifer DR.Of 57 horses with strangulating volvulus of the ascending colon, 42 were mares (including 21 postparturient mares), 8 were stallions, and 7 were geldings. Volvulus occurred most frequently in the summer (n = 24) and spring (n = 17). Pain was evaluated as severe in 41 horses, moderate in 9, and mild in 4. The abdominal fluid from 30 horses varied from clear yellow in 19 horses, to cloudy yellow in 3 horses, and serosanguineous in 8 horses. Protein content and nucleated cell count in the abdominal fluid were 2.5 +/- 1 g/dl and 1,000 +/- 900 microliters, respectively. Fifty horses had greater tha...
Allen WE, Pycock JF.Mares with persistent and recurrent endometritis are said to be susceptible to infection; in particular they are unable to resolve the acute endometritis that always follows mating. It is thought, therefore, that these mares have a local immunological defect in the uterus that impedes the elimination of bacteria. Studies on immunoglobulins, opsonins and the functional ability of neutrophils in the uterus of susceptible mares have not confirmed the presence of an impaired immune response. It is concluded that factors involved in the production and drainage of uterine fluid may be important in t...
Rose RJ, Schlierf HA, Knight PK, Plummer C, Davis M, Ray SP.In a crossover study, either a placebo paste or N,N-dimethylglycine was administered orally at a dose rate of 1.2 mg/kg twice daily for five days to six thoroughbred horses, with bodyweights ranging from 424 to 492 kg. Using previously determined regression equations for oxygen uptake (VO2) against speed for each horse, a standardised exercise test was given with speeds equivalent to fixed percentages of the maximum oxygen uptake (VO2max). The test consisted of two minutes at speeds equivalent to approximately 40 per cent and 50 per cent VO2max, and one minute at speeds that produced approxima...
Prades M, Grant BD, Turner TA, Nixon AJ, Brown MP.The clinical, radiographic, arthroscopic and pathological findings of 10 horses with injury to the cranial cruciate ligament are presented. The most consistent clinical signs included moderate to severe distension of the femoropatellar joint and a Grade III to a Grade V out of V lameness. Craniocaudal instability could be elicited in five horses under general anaesthesia and in one conscious horse. Radiographic evaluation of the stifles revealed that avulsion fracture of the medial intercondylar eminence was the most common finding in six out of 10 horses. Arthroscopic examination of the affec...
Dunlop CI, Hodgson DS, Watson JW, Gillespie JR, Steffey EP, Jackson AC.High frequency jet ventilation (HFJV) is a recently developed mode of ventilation that delivers small tidal volumes at frequencies greater than 60 cycles per min via an injection catheter to the animal's airway. The construction of a high frequency jet ventilator suitable for use in adult horses is described. The effectiveness of this ventilator in maintaining normal arterial blood-gas tension was evaluated in five healthy adult horses. The horses were anaesthetised with intravenous acetylpromazine, guaifenesin, and thiamylal, positioned in lateral recumbency and baseline measurements were mad...
Bertone AL, Ralston SL, Stashak TS.Each of 3 digestion trials (3 forage diets) was performed on 2 groups of horses 6 to 12 months after sham operation (group 1; n = 3) or large-colon resection (group 2; n = 5). Diets were alfalfa pellets, alfalfa hay, and grass hay. Feed and fecal analyses were performed to determine apparent digestion of dry matter, organic matter, and crude protein and true digestion of dry matter, organic matter, crude protein, total plant cell wall, hemicellulose, cellulose, and lignin. Additional fecal and metabolic variables determined were percentage of fecal water, total fecal water, metabolic organic m...
Craig AM, Blythe LL, Lassen ED, Rowe KE, Barrington R, Slizeski M.Fluctuations of serum vitamin E (alpha-tocopherol), cholesterol, and total lipids were monitored in 12 horses at 3-hour intervals for 72 hours. Mean coefficients of variation were 12, 5, and 15%, respectively. Statistical analyses were used to conclude that instrumentation error was accountable for only a small portion of the vitamin E variation. Results indicated that a single serum sample assay is an unsatisfactory indicator of vitamin E status in horses. These data have clinical application in the evaluation of horses suspected to be affected with equine degenerative myeloencephalopathy. Th...
Palmer SE.Five horses with apical and abaxial fractures of the proximal sesamoid bones were treated arthroscopically. Ipsilateral and contralateral triangulation were used to remove abaxial fragments; apical fragments were removed by ipsilateral triangulation. Excellent visibility of the fracture fragments was obtained with each method. Dissection and removal of fragments was accomplished with standard arthroscopic instruments, tendon-splitting knives, and curved scissors. Excellent functional and cosmetic results were achieved in all cases.
Boland CJ, Morris RS.A survey by means of a postal questionnaire was undertaken to investigate the patterns of work and the need for information of veterinary practitioners in New Zealand. Of the 670 eligible veterinarians, 399 practitioners (60 per cent) participated in the survey. Of these, 38 per cent were in large animal practice (less than 20 per cent of work devoted to cats and dogs) and 31 per cent were in small animal practice (more than 80 per cent of work with cats and dogs). The remaining 31 per cent were in mixed practice, with a workload intermediate between the other two groups. Across the entire sam...
Lavoie JP, Spensley MS, Smith BP, Mihalyi J.The uptake of colostral IgG and IgM, their serum half-lives, and the rates of endogenous synthesis of IgG and IgM were evaluated in 6 newborn foals fed bovine colostrum (principals) and 6 foals allowed to suckle their dams (controls). The principal foals were fed 400 ml of bovine colostrum (IgG, 10,000 mg/dl and IgM, 200 mg/dl) at 2-hour intervals, from 2 to 20 hours after foaling (total dose, 4 L). Serum IgG and IgM concentrations were determined by single radial immunodiffusion from birth to 98 days of age. At foaling, principal foals had no detectable serum equine IgG, but 1 control foal ha...
Cudd TA, Mayhew IG, Cottrill CM.DORSAL midline dysgenesis of the human brain, a complex
pattern of maldevelopment of sulcation and neuronal migration
occurring before 74 days gestation, has been recognised for over
fifty years. The association (68 per cent) of the so-called Dandy-
Walker syndrome (cystic dilatation of the fourth ventricle and
hypoplasia of the cerebellum) with other brain malformations is
common and often includes agenesis of the corpus callosum
(Hart, Malamud and Ellis 1972; Ral et a1 1980). This report
describes the first pre-mortem identification of such a structural
brain anomaly in a Thoroughbr...
Stadler P, Van Amstel SR.Commercially available Escherichia coli 055: B5 lipopolysaccharide was administered intravenously experimentally at a dosage of 10 micrograms/kg to 2 horses. Various clinical and clinico-pathological parameters were monitored before and after the endotoxin administration. Because of a hopeless prognosis, and for humane reasons, euthanasia was applied on both horses 6 h after administration. Values recorded for the different parameters, including the blood lactate level, were consistent with a lethal condition. It would appear that an intravenous dose of 10 micrograms/kg of endotoxin is potenti...
Cahill JI, Goulden BE.Evidence for a central nervous system component of the distal axonopathy associated with equine laryngeal hemiplegia was found in this survey of 33 horses (control, 15; subclinical, 8; clinical, 10). Significantly higher numbers of axonal spheroids were present in sections of the lateral cuneate nuclei in layngeal hemiplegic horses than in those unaffected by the disease.
Mason DE, Muir WW, Olson LE.Smooth muscle strips from the midcervical portion of the trachea and bronchial smooth muscle strips from third-generation airways of horses were placed in tissue baths, and isometric contractile force was measured. Active force was measured in response to electrical stimulation and exogenous acetylcholine. Square-wave electrical stimuli were applied at various voltages (10, 12, 15, 18, 20, 25 V), frequencies (3, 5, 10, 15, 20, 25, 30 Hz), and pulse durations (0.2, 0.5, 1.0, 1.5, 2.0 ms). Isometric contractile force increased as voltage, frequency, and pulse duration increased. Maximal contract...
Burbidge HM, Kannegieter N, Dickson LR, Goulden BE, Badcoe L.Iohexol, a water soluble non-ionic contrast agent, was evaluated for myelography in the horse. Both 300 and 350 mg iodine/ml iohexol gave diagnostic cervical myelograms. Pathological changes were limited to extradural oedema and an increase in the number of white blood cells and specific gravity in the cerebrospinal fluid two days after myelography. This increase in white blood cells in the cerebrospinal fluid was, however, much less than that recorded by other authors using metrizamide and iopamidol contrast media. These findings indicate that iohexol is a less irritant myelographic contrast ...
Tulamo RM, Bramlage LR, Gabel AA.Infectious arthritis was induced experimentally in one tarsocrural joint of six horses by intra-articular injection of 1 ml Staphylococcus-saline suspension containing 9 x 10(4) to 3 x 10(6) organisms. The corresponding contralateral joint was injected with 1 ml of saline and served as a control. The progression of the induced infectious arthritis was assessed over a nine-day period by clinical examination and sequential synovial fluid analysis with pH and lactate measurements. Changes in synovial fluid were present before clinical signs of infectious arthritis were manifested. The diagnostic ...
Eustace RA, Caldwell MN.This paper describes a method of fabricating and fitting heart bar shoes and a technique of dorsal hoof wall resection. The rationale behind the treatments and criteria for their use are described. Radiographic technique is also discussed. This article reports the treatment of a series of clinical cases described in an accompanying article (p370).
Gibson KT, Curtis CR, Turner AS, McIlwraith CW, Aanes WA, Stashak TS.Medical records of 210 horses that survived ventral midline celiotomy for at least 4 months were examined and owners were queried to determine factors contributing to incisional hernia formation. The incidence rate of incisional hernias within 4 months was 16%. Factors significantly associated with occurrence of incisional hernias were incisional drainage, closure of the linea alba with chromic gut suture material, previous midline celiotomy, excessive incisional edema, castrated male sex, postoperative leukopenia, and postoperative pain (colic). Factors not significantly associated with occur...
Walton TE, Jochim MM, Barber TL, Thompson LH.Eighteen equids were inoculated with eastern equine encephalomyelitis (EEE) and 18 equids with western equine encephalomyelitis (WEE) viruses to produce EEE virus- and WEE virus-immunized equids. Twelve surviving EEE virus-seropositive equids, 15 surviving WEE virus-seropositive equids, and 10 nonimmunized, seronegative equids (controls) were subsequently inoculated with an equine pathogenic (epizootic) strain of Venezuelan equine encephalomyelitis (VEE) virus to determine cross-protective immunity. Challenge infection produced 90% mortality in control (nonimmunized) equids, and 40% mortality ...
Pascoe DR, Stover SM.Twenty-one pregnant mares with single or twin conceptuses between 41 and 65 days of gestational age were allotted to 5 treatment groups. A ventral median celiotomy was performed in all mares. In group-1 mares (3 mares, single conceptus), the uterus and fetus were palpated for 5 minutes. In group-2 mares (3 mares, single conceptus, flunixin meglumine), 250 ml of sterile placental fluid was injected into the nongravid uterine horn. In group-3 mares (4 mares, unicornuate twin conceptuses), group-4 mares (3 mares, unicornuate twin conceptuses, flunixin meglumine), and group-5 mares (8 mares, bicor...
Maddison JE.Fifty-nine reports of suspected adverse drug reactions (ADRs) were received by the Adverse Drug Reaction Subcommittee of the Australian Veterinary Association from April 1992-March 1993 inclusive. The number of reports received/number of animals involved per species was: dogs (30/43); cats (11/14); horses (8/10); cattle (9/30); ferret (1/1). Of these, 37 (63%) were classified as definite ADRs and 12 (20%) as probable ADRs. In 10 (17%) reports an ADR could not be substantiated or there was insufficient information available to make a decision. Twenty-three reports involved apparent hypersensiti...
Trostle SS, Markel MD.Incarceration of the large colon through a rent in the gastrosplenic ligament of a horse was surgically corrected via ventral midline celiotomy. Clinical signs were similar to those in other horses with nonstrangulating large colon disorders. Diagnosis of large colon incarceration in the gastrosplenic ligament was determined by surgical abdominal exploration. The findings of medial deviation of the spleen, location of the large colon lateral to the stomach and caudolateral to the spleen, and caudocraniad passage of the large colon through the gastrosplenic ligament are similar to findings in h...
Rooney JR.An hypothesis on the pathogenesis of curb in horses is considered in the light of conformation, work and the appropriate mechanics. Prevention consists of graded work until the planter tarsal ligament has strengthened sufficiently to withstand maximum normal forces.
Mc Nally TP, Slone DE, Lynch TM, Hughes FE.To validate the safety of a suprapatellar pouch (SPP), approach to the femoropatellar joint (FPJ), and describe use of a laparoscopic cannula to remove debris or loose bodies. Methods: Retrospective case series Methods: Horses (n = 168) with osteochondritis dissecans (OCD) of the FPJ. Methods: Arthroscopy was performed on 245 FPJ with OCD. Two subpatellar portals were created, 1 axial and 1 abaxial to the lateral patellar ligament. Additionally, a SPP egress portal for lavage, was created 2 cm proximal to the most palpable dorsolateral eminence of the patellar base. A 10-mm laparoscopic cannul...
Sonmez K, Gurel A, Takai S.The aim of the present study was to develop an immunocytochemical procedure for the early detection and demonstration of Rhodococcus equi in smears of tracheal aspirates taken from live foals in field conditions. Tracheal wash samples were collected from thoroughbred foals, aged 1-5 months and located in studs around Bursa and Istanbul, Turkey. Some foals were suspected of having R. equi infection on the basis of clinical examination (n=56) and others were unaffected control animals (n=54). Serum samples were also collected from each foal for testing for the presence of R. equi-specific antibo...
Meehan LJ, Taylor SE, Labens R, Cillán-García E.Assessment of the usefulness of magnetic resonance imaging (MRI) in treatment planning in suspected cases of quittor in the horse. Methods: Five horses with chronic discharging tracts at the level of the foot underwent MRI for treatment planning. Results: The MRI examination revealed variable involvement of soft tissue and osseous structures of the foot in addition to abnormalities of the ungular cartilages in all cases. In two cases, follow-up MRI examination was performed. Four of five horses had a successful outcome, with three of these undergoing only one surgical procedure and one being m...
Lindner A, Wahdati A, Sommer H.GSH-Px activity in blood and plasma of 269 horses was determined and interrelated to age, sex, and type of use or breed. Furthermore values in blood were related to hematocrit and hemoglobin contents. Trotters and riding horses had higher GSH-Px activities in plasma as well as in blood (0.83 +/- 0.22 and 0.79 +/- 0.23 U/ml plasma or 27.2 +/- 4.3 and 24.0 +/- 7.0 U/ml blood) than Thoroughbreds in training and yearlings (0.61 +/- 0.,14 and 0.56 +/- 0.16 U/ml plasma or 20.6 2 +/- 6.9 and 24.6 +/- 4.3 U/ml blood). 3 to 6 years old Thoroughbreds had higher GSH-Px-activities than 1 to 2 years old on...
Malalana F, Ireland JL, Pinchbeck GL, McGowan CM.Risk factors for a first episode of primary uveitis in horses have not been determined. In addition, disease progression and the proportion of horses that develop recurrence following the original episode are not known. Objective: To determine the risk factors for the development of a first episode of primary uveitis in horses in the UK and to document the proportion of cases that experience recurrence following this first episode. Methods: Prospective case-control longitudinal study. Methods: Horses with a first episode of primary uveitis between July 2014 and August 2018 were recruited to th...
Furr MO, Quance J, Kennedy T.Equine protozoal myeloencephalitis (EPM) is a serious disorder of the nervous system of horses caused by Sarcocystis neurona. Recently, toltrazuril has begun to be used for treatment of EPM. The purpose of this study was to evaluate the potential toxicity of toltrazuril in horses when administered at a dose of 50 mg/kg for 10 days. Five horses were given 50 mg/kg of toltrazuril once daily for 10 days by nasogastric tube. Complete blood cell counts, serum chemistry values, and coagulation panels were evaluated before and after treatment; then a full postmortem examination was completed on day 1...
Diaz OS, Zarucco L, Dolente B, Reef VB.A 14-year-old thoroughbred gelding was presented for the evaluation of acute abdominal pain. Rectally, there was a soft fluctuant painful swelling dorsal to the bladder and to the right of the midline. The creatinine concentration of the peritoneal fluid was 15 mg/dl. Transrectal ultrasonographic examination of the urinary tract revealed a large collection of fluid dissecting from the pelvic portion of the right ureter ventrally through the right side of the bladder wall and into the retroperitoneal space, and a thickened right ureter and bladder wall at the level of the trigone. Cystoscopical...
Weidenhöfer V, Martin H, Peters J.Since the late 9th century, scientific literature in Arabian language, based on the translation and compilation of works of the Classical, Persian and Indian culture considerably increased. This also applies to the field of veterinary medicine, as is illustrated by a number of hippological and hippiatric treatises. Affinities between texts on horse medicine in Antiquity and in Arabian literature have been mentioned by philologists, but the degree of dependence on classical texts could not be verified due to the lack of translations of the Arabian texts. In this respect, the oldest available te...
Amaniti EM, Diakakis N, Patsikas M, Savvas I.Epiphyseal fracture, also known as epiphysiolysis, is the loosening or separation, either partial or complete, of an epiphysis from the shaft of a long bone. Distal epiphyseal fractures in foals pose a substantial challenge due to their guarded prognosis. This report describes the clinical signs, diagnosis, successful conservative treatment of an 1-month-old, male Skyros pony with an epiphyseal fracture of the right third metacarpal bone (type II Salter-Harris). The owner declined surgical treatment because of financial considerations along with the unfavorable prognosis. Conservative fracture...
White SD, Affolter VK, Dewey J, Kass PH, Outerbridge C, Ihrke PJ.Cutaneous vasculitis was identified by histopathological findings in 72 equines. The most frequent clinical findings were crusts/scales and oedema of the legs with the most common underlying disease being photo-aggravated dermatitis. Common laboratory findings were anaemia, neutrophilia, hyperglycaemia and hyperglobulinaemia. Histopathological patterns were most commonly cell-poor and lymphocytic/histiocytic. While statistically supported treatment recommendations could not be made due to the large numbers of confounding factors, trimethoprim-sulfa antibiotics, corticosteroids, and/or resoluti...
Fintl C, Pearson GT, Mayhew IG, Hudson NP.The generation and maintenance of intestinal motility patterns involve the complex interactions of several components including the gastrointestinal pacemaker cells (interstitial cells of Cajal, ICC). Central to ICC function is the generation of rhythmic pacemaker currents, namely slow waves, which represent the rate limiting step for intestinal smooth muscle contractions. Currently, intracellular slow wave activity has not been demonstrated in the equine colon. Objective: To characterise the in vitro myoelectrical activity of the equine pelvic flexure using intracellular recording techniques....
Gray SN, Dechant JE, LeJeune SS, Nieto JE.To investigate postoperative hemoperitoneum in a population of horses that had surgery for colic. Methods: Retrospective case series. Methods: Horses (n = 23). Methods: Preoperative, intraoperative, and postoperative information was obtained from medical records (1985-2012) of horses with postoperative hemoperitoneum after emergency exploratory celiotomy. Pre-existing hemoperitoneum during surgery and nonsurgical hemoperitoneum were excluded. Results: Of 4520 horses that had emergency exploratory celiotomy for gastrointestinal disease, 23 horses met inclusion criteria; an incidence of 0.5%. Ho...
HABEEB AF, SMITH DB.Horse globill and its conlponent polypeptide chains obtained by fractional
precipitation and column chroinatography have been ailalyzed for their con- stituent amino acids. The principal difference between the two chains is that
the valyl-leucyl chain is rich in serine and threonine and poor in glutamic acid
and tryptophan compared to the \-alyl-glutaininyl chain.
Cavalli M, Carcano R, Beretta C.Despite assays on ring preparations in vitro confirmed that the vasoconstrictor sympathetic control in the horse common digital artery mainly depends on alpha(1)-adrenoceptors stimulation, selective alpha(2)-adrenoceptor agonists were investigated under the same experimental conditions. Both detomidine (DET) and UK 14304 differed from noradrenaline (NA) and phenylephrine (PHE) in provoking contractile effects which were slowly onsetting, concentrations-unrelated and unremovable by repeated washings. While prazosin (PRA) clearly antagonized the effects of NA and PHE, neither pre- nor post-treat...