"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.
Fjordbakk CT, Strand E, Milde AK, Ihler CF, Rorvik AM.To determine clinical and diagnostic imaging findings in young horses with osteochondral fragments involving the dorsomedial aspect of the proximal interphalangeal (PIP) joint. Methods: Retrospective case series. Methods: 6 horses. Methods: Medical records were reviewed. Follow-up information was obtained through telephone conversations with owners or trainers or by examining race records. Results: Horses were between 1 and 4 years old. Three had bilateral osteochondral fragments in the forelimbs (n = 2 horses) or hind limbs (1). Radiographically, all but 1 fragment seemed to originate from th...
Balendra G, Turner M, McCrory P.It has been previously shown that professional jump and flat racing jockeys suffer a high incidence of injury as a consequence of their profession. This paper specifically examines career-ending injuries to professional jockeys in Great Britain. Objective: To investigate career-ending injuries in professional jockeys. Methods: Analysis of prospectively collected injury database on professional jockeys. Results: The majority of injuries in this study occurred to the head, shoulder or torso. Fractures were the most common type of injury that led to a decision to end a career, followed by neurolo...
Wereszka MM, White NA, Furr MO.To identify factors associated with outcome (ie, survival and return to function) following treatment of horses with septic tenosynovitis. Methods: Retrospective case series. Methods: 51 horses with septic tenosynovitis. Methods: Information was obtained from medical records and through follow-up conversations with owners. Factors analyzed for an association with outcome included affected limb, etiology, duration of clinical signs prior to examination, presence of complications, primary treatment, secondary treatments, number of surgical procedures, and hospitalization time. Results: Concurren...
Corrêa MJ, da Mota MD.The aim of this study was to estimate genetic parameters for racing performance traits in Quarter Horses in Brazil. The data (provided by the Sorocaba Jockey Club) came from 3 Brazilian hippodromes in 1994-2003, with 11 875 observations of race time and 7775 of the speed index (SI), distributed in 2403 and 2169 races, respectively. The variance components were estimated by the MTGSAM program, under animal models including the random additive genetic effect, random permanent environmental effect, and the fixed effects of sex, age and race. Heritabilities for race time and the SI, for the 3 dist...
O'Connor CI, Lawrence LM, Hayes SH.Thirteen horses of Thoroughbred or Standardbred breeding were used to study the effect of dietary fish oil supplementation on blood lipid characteristics. Horses were assigned to either fish oil (n = 7) or corn oil (n = 6) treatment groups for 63 d. The fish oil contained 10.8% eicosapentaenoic acid (EPA) and 8% docosahexaenoic acid (DHA). Each horse received timothy hay and a mixed-grain concentrate at rates necessary to maintain BW. Oil (corn or fish) was top-dressed on the concentrate daily at a rate of 324 mg/ kg of BW. The n-6:n-3 ratio was approximately 3.6:1 for horses receiving the cor...
Tryon RC, White SD, Bannasch DL.Hereditary equine regional dermal asthenia (HERDA), a degenerative skin disease that affects the Quarter Horse breed, was localized to ECA1 by homozygosity mapping. Comparative genomics allowed the development of equine gene-specific markers which were used with a set of affected horses to detect a homozygous, identical-by-descent block spanning approximately 2.5 Mb, suggesting a recent origin for the HERDA mutation. We report a mutation in cyclophilin B (PPIB) as a novel, causal candidate gene for HERDA. A c.115G>A missense mutation in PPIB alters a glycine residue that has been conserved acr...
Vashisht K, Rock RW, Summers BA.A 5-year-old National Show horse mare presented with a soft mass on the left dorsolateral aspect of the tongue. Over the next 2 years, the mare developed numerous, similar, coalescing masses that extended along the left dorsolateral aspect to the tip of the tongue. Microscopically, the bases for these masses were slender, fusiform, mesenchymal cells that formed compact whorls around myelinated and unmyelinated nerves. These cells were labeled by antibodies directed against vimentin but not by S-100. Ultrastructurally, multiple, concentrically arranged, long, slender cell processes, with discon...
Aberle KS, Hamann H, Drögemüller C, Distl O.We analysed a 610-bp mitochondrial (mt)DNA D-loop fragment in a sample of German draught horse breeds and compared the polymorphic sites with sequences from Arabian, Hanoverian, Exmoor, Icelandic, Sorraia and Przewalski's Horses as well as with Suffolk, Shire and Belgian horses. In a total of 65 horses, 70 polymorphic sites representing 47 haplotypes were observed. The average percentage of polymorphic sites was 11.5% for the mtDNA fragment analysed. In the nine different draught horse breeds including South German, Mecklenburg, Saxon Thuringa coldblood, Rhenisch German, Schleswig Draught Hors...
Kniazev SP, Nikitin SV.Two polymorphic blood group systems (E and M) of the pig Sus scrofa L. and one blood group system (D) of the horse Equus caballus L. have been studied. On the basis of phenogroup analysis, models describing the formation of the complex allele spectra of these systems and reflecting the contributions of mutations and recombinations have been constructed. The complementary relationships between the antigens determined by the variants of supergenes within the systems, as ell as the probable number and relative positions of the subloci encoding individual groups of antigens in them, have been dete...
Kvaternick V, Malinski T, Wortmann J, Fischer J.A sensitive reversed-phase HPLC-UV method was developed for the determination of firocoxib, a novel and highly selective COX-2 inhibitor, in plasma. A 1.0 mL dog or horse plasma sample is mixed with water and passed through a hydrophobic-lipophilic copolymer solid-phase extraction column to isolate firocoxib. Quantitation is based on an external standard curve. The method has a validated limit of quantitation of 25 ng/mL and a limit of detection of 10 ng/mL. The validated upper limit of quantitation was 2500 ng/mL for horses and 10,000 ng/mL for dogs. The average recoveries ranged from 88-93% ...
Naem S.Drashia megastoma (Spirurida: Habronematidae) occurs in nodules in the stomach wall and rarely free in the stomach of the horse, mule and zebra throughout the world. D. megastoma develops in the housefly Musca domestica and causes gastric haemorrhage or even perforation of the stomach. Larvae of this nematode may be found in the lung, skin and eye of the host. Scanning electron microscopy (SEM) was used to study the surface ultrastructure of adult worms of this nematode. In both sexes, the head end was separated from the rest of the body by a constriction. The stoma was infundibuliform with a ...
Stock KF, Distl O, Hoeschele I.Requirements for successful implementation of multivariate animal threshold models including phenotypic and genotypic information are not known yet. Here simulated horse data were used to investigate the properties of multivariate estimators of genetic parameters for categorical, continuous and molecular genetic data in the context of important radiological health traits using mixed linear-threshold animal models via Gibbs sampling. The simulated pedigree comprised 7 generations and 40000 animals per generation. Additive genetic values, residuals and fixed effects for one continuous trait and ...
Goff LM, Jeffcott LB, Jasiewicz J, McGowan CM.Pain originating from the sacroiliac joint (SIJ) in horses has long been associated with poor performance, yet specific diagnosis of sacroiliac dysfunction (SID) has been difficult to achieve. Clinical presentation of SID appears to fall into two categories. The first, presenting as pain and poor performance, is responsive to local analgesia of periarticular structures with poorly defined pathology. The second presents primarily as poor performance with bony pathological changes as a result of chronic instability. Diagnostic tests based on biomechanics as well as manual provocation for SIJ pai...
Witte W, Strommenger B, Stanek C, Cuny C.Methicillin-resistant Staphylococcus aureus of clonal lineage ST398 that exhibits related spa types and contains SCCmec elements of types IVa or V has been isolated from colonized and infected humans and companion animals (e.g., dog, pig, horse) in Germany and Austria. Of particular concern is the association of these cases with cases of nosocomial ventilator-associated pneumonia.
Pearson W, Charch A, Brewer D, Clarke AF.Recurrent airway obstruction (RAO), known previously as chronic obstructive pulmonary disease (COPD), is a debilitating respiratory condition that significantly contributes to lost training days and illness in racehorses. Herbs are becoming increasingly popular for the prophylaxis or treatment of the clinical signs of RAO despite a paucity of research on efficacy and safety. We evaluated the ability of an herbal composite containing garlic, white horehound, boneset, aniseed, fennel, licorice, thyme, and hyssop to reduce the clinical signs of RAO, hypothesizing that the product would safely red...
Williams GL, Amstalden M, Blodgett GP, Ward JE, Unnerstall DA, Quirk KS.Three experiments were conducted during the operational breeding season to confirm that continuous, subcutaneous infusion of low-dose GnRH would not disrupt established estrous cycles (Experiment 1), and test the hypotheses that a similar treatment would stimulate secretion of LH and induce development of ovulatory follicles in persistently anovulatory mares (Experiments 2 and 3). Treatment with GnRH (5 microg/h) increased (P<0.001) serum P4 during the luteal phase (7.7+/-0.5 versus 6.4+/-0.5 ng/mL), tended to increase serum LH (2.6+/-0.27 versus 1.9+/-0.25 ng/mL), and did not modify intero...
Ueki M, Takeshita H, Fujihara J, Ueta G, Nakajima T, Kominato Y, Kishi K, Iida R, Yasuda T.Equine (Equus caballus) deoxyribonuclease I (DNase I) was purified from the parotid gland, and its 1295-bp cDNA was cloned. The mature equine DNase I protein consisted of 260 amino acid residues. The enzymatic properties and structural aspects of the equine enzyme were closely similar to those of other mammalian DNases I. Mammalian DNases I are classified into three types--pancreatic, parotid and pancreatic-parotid-based on their tissue distribution; as equine DNase I showed the highest activity in the parotid gland, it was confirmed to be of the parotid-type. Comparison of the susceptibility ...
Sá e Silva M, da Costa MM, de Avila Botton S, Barretta C, Groff AC, de Vargas AC.Strangles is an acute and contagious disease characterized by inflammation of the upper respiratory tract of horses. The etiological agent of strangles is the bacteria S. equi subsp. equi, which belongs to the Lancefield group C. Opportunistic agents from the same group are frequently isolated from horses with strangles and may induce mistaken diagnoses. Among the subspecies of S. equi, the phenotypic features are almost undistinguishable; however, the pathogenic potential is widely differentiated. The aim of this study was to characterize S. equi isolates obtained from clinical samples of str...
Kvaternick V, Pollmeier M, Fischer J, Hanson PD.The primary objective of this study was to determine the pharmacokinetic profile of firocoxib, a novel second generation coxib, in horses. Horses were administered either a single oral or intravenous dose of firocoxib at 0.1 mg/kg in a two-period crossover study with 12 animals. The dosage was based on previously determined pharmacodynamic parameters. Oral firocoxib was well absorbed with an average bioavailability (absolute) of 79% and a Cmax of 75 ng/mL at 3.9 h. The average elimination half-life was 30 h. Following intravenous administration the average Cmax was 210 ng/mL and the eliminatio...
Haussler KK, Hill AE, Puttlitz CM, McIlwraith CW.To measure passive spinal movements induced during dorsoventral mobilization and evaluate effects of induced pain and spinal manipulative therapy (SMT) on passive vertebral mobility in standing horses. Methods: 10 healthy adult horses. Methods: Baseline vertical displacements, applied force, stiffness, and frequency of the oscillations were measured during dorsoventral spinal mobilization at 5 thoracolumbar intervertebral sites. As a model for back pain, fixation pins were temporarily implanted into the dorsal spinous processes of adjacent vertebrae at 2 of the intervertebral sites. Vertebral ...
Fumuso EA, Aguilar J, Giguère S, Rivulgo M, Wade J, Rogan D.Our objective was to characterize immune parameters in susceptible (SM) and resistant (RM) mares, with and without artificial insemination (AI) and immunomodulation. Eight RM and eight SM were selected based on their reproductive history and functional tests. Both groups of mares were evaluated during three consecutive cycles: Cycle 1, untreated cycle (control); Cycle 2, AI with dead semen; Cycle 3, AI with dead semen and immunomodulation. Endometrial biopsies were taken during the three cycles as follows: Cycle 1--at estrus, when follicles > or =35mm and at diestrus (7+/-1 days after ovulatio...
Mez JC, Dabareiner RM, Cole RC, Watkins JP.To determine clinical and radiographic abnormalities in and outcome of horses with fractures of the greater tubercle of the humerus and to develop a radiographic technique for obtaining a cranioproximal-craniodistal oblique projection of the proximal portion of the humerus in standing horses. Methods: Retrospective case series. Methods: 15 horses. Methods: Data collected from medical records included signalment, history, horse use, severity and duration of lameness, radiographic and ultrasonographic findings, treatment, and outcome. Results: All horses had a history of acute, unilateral lamene...
Vijarnsorn M, Riley CB, Ryan DA, Rose PL, Shaw RA.To determine the feasibility of the use of Fourier-transform infrared (FTIR) spectroscopy within the midinfrared range to differentiate synovial fluid samples of joints with osteochondrosis from those of control samples. Methods: 33 horses with osteochondrosis of the tarsocrural joint and 31 horses free of tarsocrural joint disease. Methods: FTIR spectroscopy of synovial fluid was used. Sixty-four synovial fluid samples from the tarsocrural joint were collected. Of these, 33 samples were from horses with radiographic evidence of osteochondrosis of the tarsocrural joint and 31 from control join...
Lescun TB, McClure SR, Ward MP, Downs C, Wilson DA, Adams SB, Hawkins JF, Reinertson EL.To evaluate clinical findings, complications, and outcome of horses and foals with third metacarpal, third metatarsal, or phalangeal fractures that were treated with transfixation casting. Methods: Retrospective case series. Animals-29 adult horses and 8 foals with fractures of the third metacarpal or metatarsal bone or the proximal or middle phalanx. Methods: Medical records were reviewed, and follow-up information was obtained. Data were analyzed by use of logistic regression models for survival, fracture healing, return to intended use, pin loosening, pin hole lysis, and complications assoc...
Toribio RE, Kohn CW, Rourke KM, Levine AL, Rosol TJ.To determine effects of experimentally induced hypercalcemia on serum concentrations and urinary excretion of electrolytes, especially ionized magnesium (iMg), in healthy horses. Methods: 21 clinically normal mares. Methods: Horses were assigned to 5 experimental protocols (1, hypercalcemia induced with calcium gluconate; 2, hypercalcemia induced with calcium chloride; 3, infusion with dextrose solution; 4, infusion with sodium gluconate; and 5, infusion with saline [0.9% NaCl] solution). Hypercalcemia was induced for 2 hours. Dextrose, sodium gluconate, and saline solution were infused for 2 ...
Olsén L, Ingvast-Larsson C, Broström H, Larsson P, Tjälve H.Case reports of 59 horses reacting adversely to procaine benzylpenicillin or to sodium or potassium benzylpenicillin in Sweden in 2003-2005 were obtained through contacts with horse-owners. For the assessment of the reports, various parameters were evaluated, such as the times to the reactions, information on previous penicillin treatment, the clinical signs and the actions taken in the reacting horses. Among the reports, two horses had received sodium or potassium benzylpenicillin intravenously, whereas the remaining 57 horses had been treated with procaine benzylpenicillin intramuscularly. A...
Peters BC, Pan Z, Christensen H, Gabriels RL.Emerging evidence suggests therapeutic horseback riding improves self-regulation behaviors, social functioning, and language in youth with autism spectrum disorder (ASD). It has been theorized that interacting with horses is calming for youth with ASD, which may influence social and language outcomes. The current study is an exploratory secondary mediation analysis of a previously published randomized controlled trial of therapeutic horseback riding for youth with ASD. We hypothesized that self-regulation would mediate therapeutic horseback riding's effect on social and language outcomes in yo...
Dunkel B, Buonpane A, Chang YM.Clinical impression suggests that some gastrointestinal lesions are more common in certain horse types. The study tested the hypothesis that relative prevalence of acute gastrointestinal lesions differs between equid types. In a retrospective caseâ€"control study, records (2010â€"2015) were reviewed for equids with acute gastrointestinal disease. Signalment, details of gastrointestinal lesions and diagnoses were recorded. Animals were categorised as miniature type, pony, Arabian, light breed or draft type. Exclusion criteria were no recorded breed/size/diagnosis, age less than one year a...
Barr AR, Dyson SJ, Barr FJ, O'Brien JK.Twenty-four horses with ultrasonographic evidence of tendonitis of the deep digital flexor tendon in the metacarpal/metatarsal region were seen over a 7 year period. Most horses had mild to moderate lameness and distension of the digital flexor tendon sheath in the affected limb. Intrasynovial analgesia of the digital flexor tendon sheath consistently improved the degree of lameness. Ultrasonography most commonly revealed small, distinct, often circular, focal hypoechoic areas within the deep digital flexor tendon which usually extended less than 1 cm proximodistally. The degree of lameness an...
Intan-Shameha AR, Divers TJ, Morrow JK, Graves A, Olsen E, Johnson AL, Mohammed HO.The current study aimed at the investigating the potential use of phosphorylated neurofilament H (pNF-H) as a diagnostic biomarker for neurologic disorders in the horse. Paired serum and cerebrospinal fluid (CSF) samples (n=88) and serum only (n=30) were obtained from horses diagnosed with neurologic disorders and clinically healthy horses as control. The neurologic horses consisted of equine protozoal myeloencephalitis (EPM) (38 cases) and cervical vertebral malformation (CVM) (23 cases). Levels of pNF-H were determined using an ELISA. The correlation between CSF and serum concentrations of p...
Anderson JD, Tulleners EP, Johnston JK, Reeves MJ.The efficacy of sternothyrohyoideus myectomy (SM) and staphylectomy as treatments for intermittent dorsal displacement of the soft palate was evaluated in 209 racehorses (126 Thoroughbreds, 83 Standardbreds). The 2 most common complaints were respiratory tract noise (75% of horses) and exercise intolerance (51% of horses). Stopping, defined as the inability to finish the race at racing speed, was reported in 40% of the horses. Endoscopy at rest revealed evidence of abnormal epiglottic anatomy (hypoplasia or flaccidity) in 51% of the horses and abnormal soft palate function in 36% of the horses...
Cohen ND, Cywes-Bentley C, Kahn SM, Bordin AI, Bray JM, Wehmeyer SG, Pier GB.Strangles is a common disease of horses with worldwide distribution caused by the bacterium Streptococcus equi subspecies equi (SEE). Although vaccines against strangles are available commercially, these products have limitations in safety and efficacy. The microbial surface antigen β 1→6 poly-N-acetylglucosamine (PNAG) is expressed by SEE. Here we show that intramuscular (IM) injection alone or a combination of IM plus intranasal (IN) immunization generated antibodies to PNAG that functioned to deposit complement and mediate opsonophagocytic killing of SEE ex vivo. However, immunization st...
Holcombe SJ, Schneider RK, Bramlage LR, Gabel AA, Bertone AL, Beard WL.Medical records of 59 racehorses with noncomminuted midsagittal proximal phalanx fractures repaired by means of lag screw fixation between 1973 and 1991 were reviewed. Fractures were classified as short incomplete fractures (7), long incomplete fractures (32), complete fractures extending into the proximal interphalangeal joint (13), and complete fractures extending through the lateral cortex of the proximal phalanx (7). Time from fracture repair to first race following fracture repair, number of racing starts, and fastest race times before and after surgery were obtained from race records and...
Holcomb KE, Tucker CB, Stull CL.Horses in the United States are commonly managed in outside pens or pastures in small groups. Limited research on shade use by domestic horses housed singly in individual pens has shown benefits and a preference for using available shade. The objective of this study was to examine the amount of shade use and the behavioral and physiological responses of small groups of horses when housed with access to shade (SH) and without access to shade (SUN). Thirty-six horses were randomized into 3 consecutive trials using 3 horses per group and 4 groups per trial. Groups experienced 5 d in each treatmen...
Horsington JJ, Gilkerson JR, Hartley CA.Equine rhinitis B virus (ERBV) is the single species in the genus Erbovirus, family Picornaviridae. Equine rhinitis B viruses exist in three serotypes and are associated with respiratory disease in horses. Members of the species vary in stability at acid pH. To date there has been discordance in genotype, serotype and acid stability phenotype groupings. To identify capsid regions associated with acid stability, two viruses were serially treated at pH 3.3 to isolate acid-stable mutants. An acid-stable mutant of the prototype acid-labile serotype 1 virus contained a single amino acid change in t...
Evans DL, Golland LC.The aim of this study was to investigate correlations between lactate concentrations in equine whole blood and plasma measured with Accusport1 and Yellow Springs Instruments (YSI2) (2300) methods. The effect of packed cell volume (PCV) on the accuracy of Accusport was also investigated. Blood samples were collected from Thoroughbred horses at 5-10 min intervals after a treadmill exercise test. Blood was added to NaEDTA (for PCV measurement) and to 2 tubes containing lithium heparin anticoagulant (for lactate assays). At concentrations greater than 10 mmol/l, Accusport1 greatly underestimated t...
Jeffcott LB, McCartney RN, Speirs VC.A safe, non-invasive method for the accurate measurement of bone mineral content in the third metacarpal bone of the horse is described. The technique involves scanning the bone with a single photon beam from an Americium-241 source. Data were obtained from the excised metacarpal bones from both forelimbs of 50 normal and seven lame horses. Measurements were made in vivo on eight normal and seven lame horses and on one experimental horse with osteopenia induced by partial weightlessness in a flotation tank. In the normal horses bone mineral content altered with age, particularly in the first s...
Tute AS, Wilkins PA, Gleed RD, Credille KM, Murphy DJ, Ducharme NG.An 8-year-old Trakehner mare developed fulminant pulmonary edema following suspected upper airway obstruction 50 minutes into an otherwise unremarkable anesthetic recovery after surgery for left cricoarytenoideus dorsalis muscle reinnervation and ventriculocordectomy. Establishing a patent airway by orotracheal reintubation and cardiopulmonary resuscitation attempts were unsuccessful. Gross, histological, and electron microscopic postmortem examination showed severe hemorrhagic pulmonary edema. Laryngeal swelling or hemorrhage were not evident, suggesting laryngospasm or functional airway coll...
Noble GK, Brockwell YM, Munn KJ, Harris PA, Davidson HP, Li X, Zhang D, Sillence MN.L-tryptophan is a common ingredient in equine calmative products, but its effectiveness has not been demonstrated in horses. Objective: To determine whether a commercial dose of L-tryptophan increases plasma tryptophan and alters behaviour in horses fed a roughage or concentrate meal. Methods: L-tryptophan (6.3 g) or placebo (water) was administered per os in a cross-over design, to 12 Thoroughbred horses (503 +/- 12.1 kg bwt), just before a meal of lucerne hay or oats. Plasma tryptophan was measured by gas chromatography. Horse behaviour was observed in an empty enclosure, then in the presenc...
Wooldridge AA, Seahorn TL, Williams J, Taylor HW, Oliver JL, Kim DY, Vicek TJ.A 2-year-old quarter horse gelding presented for evaluation of polyuria and polydipsia. Azotemia was detected on serum chemistry profile. Small, misshapen, hyperechoic kidneys with decreased corticomedullary demarcation, hydronephrosis, and a right nephrolith were noted ultrasonographically. The diagnosis of end-stage kidney disease and dysplasia was made histopathologically using ultrasound-guided biopsy. Two ureteroliths were found in the right ureter via cystoscopy, and a nephrolith was seen in the right kidney at necropsy. Clinical, ultrasonographic, and pathologic features of equine uroli...
de Miguel Garcia C, Campoy L, Parry S, Miller JE, Martin-Flores M, Gleed RD.To collect data about the current practice of recovering horses from general anesthesia and recovery personnel safety. Methods: Online survey. Methods: An online questionnaire, including questions on general demographic data, recovery drugs, modality and characteristics of equine recovery and morbidity and mortality, was designed and distributed via e-mail to equine practitioners worldwide. Results: Practitioners from 22 countries completed 373 questionnaires; 53% of the participants were board-certified equine surgeons, and the remainder were board-certified anesthesiologists (18%), large ani...
Miranda-de la Lama GC, González-Castro CA, Gutiérrez-Piña FJ, Villarroel M, Maria GA, Estévez-Moreno LX.The study presents a novel veterinary forensic approach to analyse the bruising of horse carcasses, based on the nature of the bruises and how they are grouped in certain anatomical areas. Data on pre-slaughter logistics was obtained for 113 journeys with horses that travelled from Mexico and the USA to a Mexican abattoir. We found that carcass bruising was a highly prevalent problem (79% of carcasses had bruising) and was especially problematic in journeys lasting longer than 12 h, independently of the animal's country of origin, sex, age, lairage time or vehicle type. Multivariable logistic...
Liu SK, Dolensek EP, Adams CR, Tappe JP.Degenerative myelopathy was diagnosed in six Mongolian wild horses. Three of the horses had a history of ataxia dating from birth to 3 months of age. The clinical signs were uncoordinated movement of the hindlimbs and an abnormally wide-based gait and stance. The other 3 horses had mild ataxia. There were no gross lesions in the brain, vertebrae, or spinal cord. Histologic examination revealed degeneration of the neural processes in the ventral and lateral funiculi of all 6 horses. Myelin sheaths were dilated and vacuolated, and there were swollen, fragmented, or lysed axons. Neuronal degenera...
Nakamae Y, Ishihara A, Itoh M, Yanagawa M, Sasaki N, Yamada K.Computed tomography (CT) was performed for an 18-year-old female pony with enterolithiasis in the prone and supine positions. CT images from the prone position revealed displacement of the large dorsal colon, which contained an enterolith to the ventral side of the abdomen, and those from the supine position revealed displacement to the dorsal side. A high-density material suggestive of a metallic foreign body was also observed in the enterolith core. An enterolith (422 g, 104 mm) was surgically removed from the large dorsal colon. This caused no complications after surgery and increased the h...
Magee AA, Galuppo LD.To determine the bursting strength of ventral median abdominal incisions closed by either simple continuous or inverted cruciate suture patterns. Methods: Experimental. Methods: Twelve equine cadavers. Methods: A 25 cm ventral median incision was made through the linea alba and a 200 L polyurethane bladder was placed within the abdomen. Either a simple continuous or an inverted cruciate pattern using 3 polyglactin 910 with a bite size and suture interval of 1.5 cm was used to close linea incisions. Closure time was recorded for each pattern. The bladder was inflated with air at 40 L/min, and t...
Durando MM, Slack J, Birks E, Belcher C, Kohn C.Injuries and sudden death during the cross-country (XC) phase of eventing have raised interest in the frequency and types of cardiac arrhythmias occurring in these equine athletes. Objective: To characterise the frequency and types of rhythm disturbances and examine possible risk factors for premature depolarisations (PDs) occurring during the XC phase of United States Eventing Association (USEA) and Fédération Equestre Internationale (FEI)-sanctioned events. Methods: Prospective, cross-sectional study. Methods: Continuous electrocardiographic (ECG) recordings were obtained from horses prior...
Stewart AJ, Behrend EN, Wright JC, Martin LG, Kemppainen RJ, Busch KA, Hanson RR.To determine the lowest ACTH dose that would induce a maximum increase in serum cortisol concentration in healthy adult horses and identify the time to peak cortisol concentration. Methods: Evaluation study. Methods: 8 healthy adult horses. Methods: Saline (0.9% NaCl) solution or 1 of 4 doses (0.02, 0.1, 0.25, and 0.5 μg/kg [0.009, 0.045, 0.114, and 0.227 μg/lb]) of cosyntropin (synthetic ACTH) were administered IV (5 treatments/horse). Serum cortisol concentrations were measured before and 30, 60, 90, 120, 180, and 240 minutes after injection of cosyntropin or saline solution; CBCs were per...
Harris PA.The paper provides some basic epidemiological and clinical descriptive information for the equine rhabdomyolysis syndrome (ERS) in the United Kingdom. Information was obtained retrospectively from laboratory submission data as well as cases investigated by the author via their veterinary surgeon. Sex appeared to be a significant variable, with females being more likely than males to suffer from ERS compared to other conditions (P less than 0.01). More samples were submitted in the period November-February than at other times of the year (P less than 0.01). The condition appeared to be found in...
Imaizumi K, Nakamura T, Kiryu K, Kanemaru T, Kaneko M.The aorta and extrapulmonary artery were examined pathologically in 33 thoroughbred racehorses ranging in age from 1 to 5 years. Many of the great vessels of these horses exhibited degenerative or sclerotic changes in the media with neither lipidosis nor deposits of cholesterol. The severe lesions were predominantly observed at the bifurcation of the pulmonary artery. The severity of the lesions in both the aorta and pulmonary artery appeared to be associated with the racing career of the racehorse rather than with increasing age. Histopathogenetically, the medial changes in the great vessels ...
Cardo MV, Carbajo AE, Mozzoni C, Kliger M, Vezzani D.Blood feeding patterns of mosquitoes are a key component in the dynamics of arboviral encephalitides transmission. In temperate Argentina, the members of the Culex pipiens complex include Cx. pipiens molestus, Cx. quinquefasciatus and their hybrids. To characterize their blood feeding patterns, adult resting mosquitoes were collected monthly during the warm season in urban and rural equestrian fields. The availability of birds and domestic mammals per site was characterized. The blood source and the complex member were successfully identified for 89 specimens using PCR. Blood of 19 vertebrate ...
Liu IK, Turner JW, Van Leeuwen EM, Flanagan DR, Hedrick JL, Murata K, Lane VM, Morales-Levy MP.In this study of equids, we investigated the antibody response and the effect on the estrous cycle following a single inoculation of porcine zonae pellucidae (pZP) employing controlled-release methodology. We also investigated the use of two different water-soluble adjuvants as an alternative to oil-based adjuvants. Twenty-seven domestic mares were inoculated with various formulations of pZP and adjuvant. We showed that the anti-pZP antibodies generated as a result of the inoculations persisted for at least 43 weeks (length of the study). Of the various formulations used in the study, pZP and ...
Grenager NS.Endocrinopathic laminitis (EL) primarily occurs because of insulin dysregulation (ID) mediated through downstream effects of insulin on IGF-1R in lamellar tissues. There is likely contributing vascular and metabolic dysfunction within the lamellae, but EL is relatively non-inflammatory. EL is associated with lamellar stretching, proliferation, and failure, ultimately causing failure of the suspensory apparatus of the distal phalanx. Proper education regarding mitigating risk factors makes this a largely preventable cause of laminitis. Annual hoof evaluation plus screening geriatric horses for ...
Smith MC, Bass L, Damone J, Mama K, Rao S.The ideal field anaesthetic protocol for castration will offer an adequate duration and depth of anaesthesia using a single injection without compromising safety or recovery quality. Objective: The objective of this study was to compare intravenous (IV) xylazine and detomidine as sedatives in combination with midazolam and ketamine for induction of anaesthesia in horses undergoing field castration. Methods: Randomised, blinded, clinical study. Methods: Fifty-seven male Quarter Horses were randomly assigned to receive xylazine (group X) (1.1 mg/kg bwt) or detomidine (group D) (0.03 mg/kg bwt)...
Shappell KK, Derksen FJ, Stick JA, Robinson NE.Effects of ventriculectomy and prosthetic laryngoplasty on upper airway flow mechanics and blood gas tensions in exercising horses with induced left laryngeal hemiplegia were assessed. Five adult horses were trained to stand, trot (4.5 m/s), and gallop (7.2 m/s) on a treadmill (6.38 degrees incline). Inspiratory and expiratory airflows (VImax, VEmax, respectively) were measured using a 15.2-cm diameter pneumotachograph in a face mask. Inspiratory and expiratory transupper airway pressures (PuI, PuE, respectively) were determined as pressure differences between barometric pressure and lateral t...
