Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Hartmann C, Gerner W, Walter I, Saalmüller A, Aurich C.In the mare, early pregnancy loss is common, but involvement of the maternal immune system in the pathogenesis of this condition has not been investigated in detail so far. In the present study, we assessed effects of exposure of the endometrium to semen or seminal plasma in oestrous mares on the response of regulatory T lymphocytes (Tregs) in the peripheral circulation as well as in the endometrium. Raw semen, seminal plasma or PBS (control) were introduced into the uterus of oestrous mares (n = 12). Blood was collected immediately before insemination or PBS infusion (time 0), and 12, 24 ...
Zavodovskaya R, Stover SM, Murphy BG, Katzman S, Durbin-Johnson B, Britton M, Finno CJ.Osteoporosis has been associated with pulmonary silicosis in California horses exposed to soils rich in cytotoxic silica dioxide crystals, a syndrome termed silicate associated osteoporosis (SAO). The causal mechanism for the development of osteoporosis is unknown. Osteoporotic lesions are primarily located in bone marrow-rich sites such as ribs, scapula and pelvis. Gene transcription patterns within bone marrow and pulmonary lymph nodes of affected horses may offer clues to disease pathobiology. Bone marrow core and tracheobronchial lymph node tissue samples harvested postmortem from affected...
Sandow C, Fugler LA, Leise B, Riggs L, Monroe WT, Totaro N, Belknap J, Eades S.Laminitis has a considerable impact on the equine industry. Endocrinopathic laminitis is the most common form and affected horses often have hyperinsulinaemia due to an underlying metabolic disorder. Objective: The aim of this study was to determine if insulin weakens the structural integrity of digital lamellae and to develop an ex vivo model for the study of hyperinsulinaemia-induced lamellar failure. Methods: Ex vivo experiment. Methods: Biomechanical testing was used to assess the structural integrity of lamellar explants exposed to either medium alone (control) or medium supplemented with...
Ferrer MS, Miller LMJ.Antisperm antibodies (ASAs) have been associated with infertility in stallions. The objectives of this study were to investigate the frequency of ASA-positive semen samples in satisfactory and non-satisfactory breeder stallions, the association between ASA binding and semen quality, and factors that may affect the diagnosis. Breeding soundness examinations were performed in 21 stallions and the percentage of IgG- and IgA-bound spermatozoa was evaluated using flow cytometry. Median IgG and IgA binding did not differ between the first and second ejaculates. The percentage of IgA-bound spermatozo...
Nielsen MK, Branan MA, Wiedenheft AM, Digianantonio R, Scare JA, Bellaw JL, Garber LP, Kopral CA, Phillippi-Taylor AM, Traub-Dargatz JL.Equine strongyle parasites are considered ubiquitous in grazing equids across the world, and cyathostomin parasites are known pathogens causing well-described disease complexes in horses. Decades of intensive anthelmintic treatments have led to anthelmintic resistance in cyathostomins, and current recommendations are to lower treatment intensity and base control strategies on fecal egg count surveillance. Little is known about risk factors associated with strongyle parasite egg shedding patterns in the United States equine population, as the most recent national survey was conducted 20 years a...
Roska S, Morello S, Rajamanickam V, Smith LJ.Effects of lactated Ringer's solution (LRS) and hetastarch 130/0.4 (HES) on colloid osmotic pressure (COP), plasma osmolality (OSM) and total protein (TP) were investigated in 18 inhalational-anaesthetised healthy horses. Horses received 4-6 ml/kg LRS (LRS; n=9) or HES (HES; n=9) from anaesthesia induction through 60 min, after which all were administered LRS. COP, TP and OSM were measured before premedication (baseline), postinduction and 30 (n=18), 60 (n=18), 90 (n=18) and 120 (n=12) minutes. Baseline COP, OSM and TP were not different between groups. TP decreased in both groups at all t...
Salem SE, Maddox TW, Berg A, Antczak P, Ketley JM, Williams NJ, Archer DC.Colic (abdominal pain) is a common cause of mortality in horses. Change in management of horses is associated with increased colic risk and seasonal patterns of increased risk have been identified. Shifts in gut microbiota composition in response to management change have been proposed as one potential underlying mechanism for colic. However, the intestinal microbiota in normal horses and how this varies over different seasons has not previously been investigated. In this study the faecal microbiota composition was studied over 12 months in a population of horses managed at pasture with minima...
Satué K, Marcilla M, Medica P, Cravana C, Fazio E.Growth hormone (GH) and insulin-like growth factor (IGF-I) exert essential functions to maintain an adequate metabolic activity for correct placental and fetal development. Although fructosamine (FRUCT) is used in clinical evaluation to assess the glycaemic state, the relationships between GH, IGF-I and FRUCT remain unknown in the mare. Therefore, the objectives of this study were to evaluate the relationships among these parameters in pregnant mares. A total of 30 healthy Spanish Purebred mares, with an age range of 9.33 ± 3.31 years, were studied during the 11 months of gestation. Serum...
Haussler KK.Manual therapies involve the application of the hands to the body, with a diagnostic or therapeutic intent. Touch therapies, massage, joint mobilization, and manipulation are all critical components in the management of muscular, articular, and neurologic components of select injuries in performance horses. Musculoskeletal conditions that are chronic or recurring, not readily diagnosed, or are not responding to conventional veterinary care may be indicators that manual therapy evaluation and treatment is needed.
Tan Y, Lam TT, Heberlein-Larson LA, Smole SC, Auguste AJ, Hennigan S, Halpin RA, Fedorova N, Puri V, Stockwell TB, Shilts MH, Andreadis T....Eastern equine encephalitis virus (EEEV) has a high case-fatality rate in horses and humans, and Florida has been hypothesized to be the source of EEEV epidemics for the northeastern United States. To test this hypothesis, we sequenced complete genomes of 433 EEEV strains collected within the United States from 1934 to 2014. Phylogenetic analysis suggested EEEV evolves relatively slowly and that transmission is enzootic in Florida, characterized by higher genetic diversity and long-term local persistence. In contrast, EEEV strains in New York and Massachusetts were characterized by lower genet...
Frank N.Equine athletes are affected by 2 major endocrine/metabolic disorders, insulin dysregulation (ID) and pituitary pars intermedia dysfunction. ID is a risk factor for laminitis in horses, which poses the greatest threat to performance because of the damage that it causes to hoof structures. This article includes an in-depth discussion of ID and other risk factors for laminitis that are grouped together as equine metabolic syndrome. As horses age, the risk of pituitary pars intermedia dysfunction increases, and this endocrine disorder may exacerbate preexisting ID and further increase the risk of...
Kumar K, Arshad SS, Selvarajah GT, Abu J, Toung OP, Abba Y, Yasmin AR, Bande F, Sharma R, Ong BL.Japanese encephalitis (JE) is a vector-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). It causes encephalitis in human and horses, and may lead to reproductive failure in sows. The first human encephalitis case in Malaya (now Malaysia) was reported during World War II in a British prison in 1942. Later, encephalitis was observed among race horses in Singapore. In 1951, the first JEV was isolated from the brain of an encephalitis patient. The true storyline of JE exposure among humans and animals has not been documented in Malaysia. In some places such as Sarawak, JEV ha...
Zhang XJ, Li HL, Deng DY, Ji C, Yao XD, Liu JX.Tetanus is still a major cause of human deaths in several developing countries. In particular, the neonatal form remains a significant public health problem. According to the World Health Organization, administration of tetanus toxoid is recommended for neonatal tetanus patients. Furthermore, tetanus antitoxin or anti-tetanus immunoglobulin (Ig) are used for mild case or intensive care. This paper discusses a novel purification technique for improving equine anti-tetanus Ig production. First, equine plasma dealt with two steps salting out with ammonium sulfate; second, ultrafiltration concentr...
Valberg SJ.Optimal function of skeletal muscle is essential for successful athletic performance. Even minor derangements in locomotor muscle function will impact power output, coordination, stamina, and desire to work during exercise. In this review, the presenting clinical signs, differential diagnoses, approach to diagnostic testing and treatment of muscle atrophy and weakness, focal muscle strain, and exertional myopathies are discussed. Exertional myopathies include polysaccharide storage myopathies, recurrent exertional rhabdomyolysis, malignant hyperthermia, and myofibrillar myopathy.
Stokol T, Serpa PBS, Brooks MB, Divers T, Ness S.Equine herpesvirus type 1 (EHV-1) is a major cause of infectious respiratory disease, abortion and neurologic disease. Thrombosis in placental and spinal vessels and subsequent ischemic injury in EHV-1-infected horses manifests clinically as abortion and myeloencephalopathy. We have previously shown that addition of heparin anticoagulants to equine platelet-rich plasma (PRP) can abolish ex vivo EHV-1-induced platelet activation. The goal of this study was to test whether platelets isolated from horses treated with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) were resista...
Bubeck KA, Aarsvold S.For successful diagnosis of soft tissue injuries in the sport horse, localizing the area of injury during clinical and lameness evaluation will be followed in most cases by an ultrasonographic examination. With MRI more available in equine veterinary clinics, this modality can allow for a complete evaluation of soft tissue and osseous structures and is especially useful for evaluation of structures within the hoof capsule. This article discusses special ultrasonographic techniques, an overview of MRI image generation, and the use of contrast computed tomography for diagnosis of soft tissue inj...
García-López JM.Pain localized to the neck, back, and or pelvis can result in a profound effect on the horse's performance. These conditions can present with a varied and nonspecific set of clinical signs. A careful and thorough examination of these areas by means of physical examination, lameness evaluation both in hand and under saddle, diagnostic anesthesia, and the use of multiple imaging modalities in combination is often necessary to have an accurate prognosis. Medical and surgical management where appropriate of the conditions highlighted in this article are discussed as well as their individual progno...
Wormstrand B, Østevik L, Ekman S, Olstad K.Failure of the cartilage canal blood supply leads to ischemic chondronecrosis which causes osteochondrosis, and osteochondral lesions. Osteochondrosis is a disease with a heritable component and usually occurs under aseptic conditions. Because bacteria can bind to growth cartilage and disrupt the blood supply in pigs and chickens, we considered whether this might play a role in development of equine osteochondrosis. The aim of this study was to examine whether bacteria are present in canals in the growth cartilage of foals with septic arthritis/osteomyelitis, and whether this is associated wit...
Mueller RS, Jensen-Jarolim E, Roth-Walter F, Marti E, Janda J, Seida AA, DeBoer D.In human patients with seasonal allergic rhinoconjunctivitis sensitized to grass pollen, the first successful allergen immunotherapy (AIT) was reported in 1911. Today, immunotherapy is an accepted treatment for allergic asthma, allergic rhinitis and hypersensitivities to insect venom. AIT is also used for atopic dermatitis and recently for food allergy. Subcutaneous, epicutaneous, intralymphatic, oral and sublingual protocols of AIT exist. In animals, most data are available in dogs where subcutaneous AIT is an accepted treatment for atopic dermatitis. Initiating a regulatory response and a pr...
Baldwin AL, Chea I.This study explored whether aromatherapy increases the parasympathetic component (root mean square of successive differences [RMSSD]) of heart rate variability (HRV) in horses. Horses are highly sensitive, easily stressed, have an acute sense of smell, and have been shown to benefit from aromatherapy. The protocol, performed on eight dressage horses, followed a crossover design with an experimental treatment of humidified essential oil (lavender, Lavandula angustifolia) and a control treatment of humidified air. Heart rate variability was recorded for 7 minutes before, during, and immediately...
Paras KL, George MM, Vidyashankar AN, Kaplan RM.Gastrointestinal nematode parasites are important pathogens of all domesticated livestock species. Fecal egg counts (FEC) are routinely used for evaluating anthelmintic efficacy and for making targeted anthelmintic treatment decisions. Numerous FEC techniques exist and vary in precision and accuracy. These performance characteristics are especially important when performing fecal egg count reduction tests (FECRT). The objective of this study was to compare the accuracy and precision of three commonly used FEC methods and determine if differences existed among livestock species. In this study, ...
Arana Valencia N, Thompson DL, Southerland CV.Four experiments assessed factors affecting prolactin responses to sulpiride administration in horses. Experiment 1 compared the efficacy of the (-) enantiomer of sulpiride to that of the commonly used (+/-) racemic mixture. Mares were used in an 8 × 8 Latin square to compare the prolactin responses to four doses of levosulpiride to four corresponding doses of the racemic mixture at twice the dose. Responses at each dose indicated equal and similar (P > .1) responses. Experiment 2 compared the efficacy of 1 gram of orally administered racemic sulpiride to 100 mg of intramuscularly injec...
AbouEl Ela NA, El-Nesr KA, Ahmed HA, Brooks SA.Severe combined immunodeficiency (SCID) is a fatal genetic disorder and one of the common genetic diseases of the Arabian horse. The genetic mutation responsible for this disease is a five base pair deletion (TCTCA) in the DNA-protein kinase catalytic subunit gene. Severe combined immunodeficiency is a recessive autosomal genetic disorder with 25% chance inheritance of the disease among the progeny of carrier parents. It causes complete absence of certain immune cells, like B and T lymphocytes, leaving foals with immunodeficiency and exposing them to early death within 4 to 6 months. This stud...
Jensen AM, Ahmed W, Elbrønd VS, Harrison AP.It has been proposed that manipulating proprioceptive signals of the equine distal limb as part of a rehabilitation process in cases of musculoskeletal pain or neurologic deficits can be used to correct postural control and restore normal motor programs. This trial has examined the effect of treatment with a light-weight and loose-fitting bell boot (82 g) on an imbalance of muscle gluteus superficialis function in horses as measured using acoustic myography (AMG). Eight horses were trained over a 60-minute period every 3 days for 6 weeks, a protocol based on preliminary findings. Acoustic my...
Gautier C, Schmidt K, Aurich J, Aurich C.The hypothesis in this study was continuous treatment of stallions with the GnRH agonist deslorelin inhibits reproductive functions. A 2-week pre-experimental period was followed by an 11-week deslorelin implant treatment. Stallions received 4.7 (D1, n = 7), or 18.8 mg deslorelin (D2, n = 5) or remained untreated (C, n = 5). Libido, sperm motility, membrane integrity, DNA fragmentation, estrogen receptors, basal plasma testosterone and Anti Muellerian hormone (AMH) concentrations were evaluated once weekly during the treatment period. The testosterone response to the GnRH agonist buserelin a...
Mund SJK, Corbett C, MacPhee DJ, Campbell J, Honaramooz A, Wobeser B, Barber SM.Horses often sustain cutaneous wounds and healing can be prolonged and difficult to treat. Compared to body wounds, limb wounds heal slower and are more likely to develop exuberant granulation tissue. Differences in healing rates and exuberant granulation tissue formation is attributed to abnormal cytokine profiles. CXCL8 and its receptor CXCR2 are involved in acute inflammation whereas CXCL10 and its receptor CXCR3 are involved in inflammation resolution. β- arrestin-2 regulates inflammation through internalization of G-protein coupled receptors (GPCRs) including CXCR2 and CXCR3. Gene expres...
Ross DJ, Roberts JL.Equine calming products (ECPs) are often used by horse owners to alter or mitigate unwanted or dangerous behaviors in various situations. Little scientific research to date examines horse owners' knowledge surrounding these products. The objective of this pilot survey was to determine horse owners' use and perceptions of ECPs. For convenience, a survey was distributed to riding club members, livery yards, and riding instructors in the North of Scotland, UK, to ascertain the following information; the number of horse owners and caretakers who use an ECP, whether the product was considered to be...
Jeawon SS, Katz LM, Galvin NP, Fogarty UM, Duggan VE.Although umbilical cord blood gas analysis is considered the best way to assess in utero oxygenation in human neonates, there is limited evaluation of this method in equine neonatology. Our objectives were to assess the practicality of obtaining umbilical cord blood gas samples in the field and to determine umbilical cord arterial and venous blood gas reference intervals (RI) for healthy, newborn foals. Thoroughbred foals >320 days gestation from healthy mares with uneventful pregnancies at one stud farm were evaluated. All parturitions were observed, with paired umbilical arterial and venous ...
Crispe EJ, Secombe CJ, Perera DI, Manderson AA, Turlach BA, Lester GD.Exercise-induced pulmonary haemorrhage (EIPH) is considered a progressive disease based on histopathology, but it is unknown if tracheobronchoscopic EIPH severity worsens over time. Objective: The aim of this study was to examine tracheobronchoscopic EIPH changes over time in a population of Thoroughbred racehorses. A secondary aim was to identify factors that affect changes in tracheobronchoscopic EIPH severity between observations. Methods: Prospective, longitudinal, observational cross-sectional study. Methods: Thoroughbred racehorses were examined with tracheobronchoscopy no earlier than 3...
Morris LHA.The development of techniques to produce equine embryos in vitro is reviewed with specific reference to intracytoplasmic sperm injection (ICSI). Unexplored 50 years ago, this technology has progressed rapidly in the last 20 years to become a commercial reality for the equine breeding industry. Improvements in our understanding of oocyte and embryo competence in the horse have been key factors in overcoming some of the initial problems associated with ICSI. It is now possible to obtain high nuclear maturation and cleavage rates in vitro and the most limiting factor, presently, is the low rate o...
Art T, Franck T, Lekeux P, de Moffarts B, Couëtil L, Becker M, Kohnen S, Deby-Dupont G, Serteyn D.The aim of this work was to measure the myeloperoxidase (MPO) concentration in bronchoalveolar lavage (BAL) fluid collected from horses with recurrent airway obstruction (RAO), both in crisis and in remission, as well as from healthy horses. Seven horses with RAO were exposed to moldy hay until the maximum change in pleural pressure was greater than 1.5 kPa. At that point, BAL was performed, and the total cell counts and percentages in the fluid were immediately determined. To measure the MPO concentration in BAL-fluid supernatant, we used a specific enzyme-linked immunosorbent assay with poly...
Borchers K, Wolfinger U, Ludwig H, Thein P, Baxi S, Field HJ, Slater JD.Two 18-month-old naturally reared ponies were used to investigate the pathogenicity of EHV-2. After dexamethasone treatment, pony 1 was inoculated intranasally with EHV-2 strain T16, which has been isolated from a foal with keratoconjunctivitis superficialis and pony 2 was similarly inoculated with strain LK4 which was originally isolated from a horse with upper respiratory tract disease. Following virus inoculation, pyrexia was not detected in either pony but both developed conjunctivitis, lymphadenopathy, and coughing. EHV-2 was detected in nasal mucus samples up to day 12 post infection (p....
Humphreys JM, Pelzel-McCluskey AM, Cohnstaedt LW, McGregor BL, Hanley KA, Hudson AR, Young KI, Peck D, Rodriguez LL, Peters DPC.Mosquito-borne West Nile virus (WNV) is the causative agent of West Nile disease in humans, horses, and some bird species. Since the initial introduction of WNV to the United States (US), approximately 30,000 horses have been impacted by West Nile neurologic disease and hundreds of additional horses are infected each year. Research describing the drivers of West Nile disease in horses is greatly needed to better anticipate the spatial and temporal extent of disease risk, improve disease surveillance, and alleviate future economic impacts to the equine industry and private horse owners. To help...
Clark KE, Squires EL, McKinnon AO, Seidel GE.Equine embryos were recovered nonsurgically 6.5 d after ovulation (Exp. 1) and those greater than 200 microns were stored in one of three media: 1) Ham's F10 + 10% fetal calf serum (FCS) under 5% CO2, 5% O2 and 90% N2 at 24 C (Ham's F10); 2) Minimal Essential Medium with Hank's balanced salts + 10% FCS in air (MEM) at 24 C or 3) MEM at 5 C n = 10/treatment). Embryos less than or equal to 200 micron (n = 10) were bisected microsurgically; one-half of each embryo was stored in Ham's F10 and the other half in either Dulbecco's phosphate-buffered saline + 10% FCS in air at 24 C (DPBS), or MEM in a...
Peng TL, Armiladiana MM, Ruhil HH, Maizan M, Choong SS.The occurrence of Setaria digitata in a horse is reported for the first time in Malaysia. An 8-year-old Thoroughbred cross mare was referred to the University Veterinary Clinic with the primary complaint of corneal opacity and excessive eye discharge. After initial treatment with Terramycin eye ointment, corneal opacity cleared partially to reveal a moving thread-like cylindrical worm in the anterior chamber of the eye. The parasite was successfully removed surgically, and examination under the light microscope revealed that the isolated worm (length = 45 mm) was a 5th stage larva of S. ...
McKenzie EC, Valberg SJ, Godden SM, Finno CJ, Murphy MJ.To determine the effect of oral administration of dantrolene sodium on serum creatine kinase (CK) activity after exercise in horses with recurrent exertional rhabdomyolysis (RER). Methods: 2 healthy horses and 5 Thoroughbreds with RER. Methods: 3 horses received 2 doses of dantrolene (4, 6, or 8 mg/kg, p.o., with and without withdrawal of food) 2 days apart; 90 minutes after dosing, plasma dantrolene concentration was measured spectrofluorometrically. On the basis of these results, 5 Thoroughbreds with RER from which food was withheld received dantrolene (4 mg/kg) or an inert treatment (water ...
Krajaejun T, Kittichotirat W, Patumcharoenpol P, Rujirawat T, Lohnoo T, Yingyong W.Genome sequences are a vital resource for accelerating the biological exploration of an organism of interest. Pythium destruens (a synonym of Pythium insidiosum) causes a difficult-to-treat infectious disease called pythiosis worldwide. Detection and management of pythiosis are challenging. Basic knowledge of the disease is lacking. Genomes of this organism isolated from different continents (i.e., Asia and the Americas) have been sequenced and publicly available. Here, we sequenced the genome of an Australian isolate of P. destruens. Genome data will facilitate the comparative analysis of thi...
Greet TR.This paper describes the outcome of treatment of 30 cases of guttural pouch mycosis by ligation of the internal carotid artery on the cardiac side of the lesion and lavage of the affected pouch with natamycin. Twenty-three horses recovered fully following this treatment while laryngeal hemiplegia persisted in one case and slight dysphagia caused by pharyngeal hemiplegia in another. The remaining five horses died or were destroyed. Five horses with guttural pouch mycosis, which had shown no epistaxis but had pharyngeal hemiplegia, were treated by topical natamycin alone. Only two of these survi...
Hunt RJ.Case records of 202 horses treated for laminitis were reviewed with the intent of determining the long-term outcome and correlating this with digital radiographic findings and with the degree of pain associated with the laminitis. At long-term follow-up 57 horses had returned to athletic soundness (Group 1), 20 horses were intermittently lame (Group 2), 19 horses had permanent severe lameness (Group 3), 97 were dead (Group 4), and 9 were lost to follow up. Using simple regression analysis, functional outcome did not correlate with the degree of rotation (R2 = 0.004) or the presence of distal d...
O'Banion MK, Reichmann ME, Sundberg JP.Equine papillomaviruses (EqPV) from naturally occurring cases of cutaneous papillomatosis in several ponies and one horse were isolated, cloned, and characterized. Group specific papillomavirus structural antigens were detected in sections of the papillomas by the peroxidase-antiperoxidase technique, and virions were observed in the in the nuclei of cells in the stratum granulosum and corneum. Negatively stained virions purified from papilloma homogenates by isopycnic CsCl centrifugation were 55 nm in diameter and had typical papillomavirus morphology. The entire viral genomes of two separate ...
Michelotto PV, Muehlmann LA, Zanatta AL, Bieberbach EWR, Kryczyk M, Fernandes LC, Nishiyama A.This study investigated the putative roles of inflammation and platelet-activating factor (PAF) in exercise-induced pulmonary haemorrhage (EIPH). Two-year-old Thoroughbred colts (n=37) were exercised on a racetrack for 5months before commencement of the study. Each colt was then exercised at 15-16m/s over 800-1000m and broncho-alveolar lavage fluid (BALF) was collected 24h later. The colts were subsequently divided into two groups on the basis of BALF analysis; an EIPH-positive group (presence of haemosiderophages, n=23) and an EIPH-negative group (absence of haemosiderophages, n=14). BALF fro...
Tabynov K, Kydyrbayev Zh, Ryskeldinova Sh, Assanzhanova N, Sansyzbay A.We previously created a live vaccine against equine influenza based the new reassortant cold-adapted (Ca) strain A/HK/Otar/6:2/2010. The live vaccine contains surface proteins (HA, NA) from the wild-type virus A/equine/Otar/764/2007 (Н3N8; American Lineage Florida Clade 2), and internal proteins (PB2, PB1, PA, NP, M, NS) from the attenuated Ca donor virus A/Hong Kong/1/68/162/35CA (H3N2). To determine the safety and duration of the protective immune responses, 90 yearlings were intranasally vaccinated in single mode, double mode at an interval of 42 days (10(7.0) EID50/animal for both vaccina...
Gorvy DA, Barrie Edwards G, Proudman CJ.The objectives of this study were (1) to determine the prevalence of pathological abdominal adhesion formation following exploratory laparotomy; (2) to establish the site of adhesion formation and its relationship to the initial lesion; (3) to ascertain whether the development of intra-abdominal adhesions decreases long-term survival and (4) to identify risk factors for adhesion formation. Of 1014 horses treated surgically for acute gastrointestinal disease, 113 (10.1%) were subjected to repeat laparotomy, with surgical records available for 99 of these cases. Pathological adhesions were the m...
Patan-Zugaj B, Gauff FC, Licka TF.To examine the effect of endotoxins on metabolism and histopathologic changes of isolated perfused equine forelimbs. Methods: Forelimbs (comprising the metacarpus and digit) were collected from cadavers of 12 healthy adult horses after slaughter at an abattoir (14 limbs; 1 forelimb of 10 horses and both forelimbs of 2 horses). Methods: Forelimbs were perfused for 10 hours with autologous blood, with and without the addition of endotoxin (80 ng of lipopolysaccharide [LPS]/L). Two limbs of the endotoxin exposure group and 2 nonperfused limbs were loaded to failure of the suspensory apparatus of ...
Cousty M, Rossier Y, David F.The traditional techniques for injection of the sacroiliac (SI) region are based on external landmarks. Because of the depth of the SI joint and pathological modifications, SI injections are sometimes challenging in horses. Objective: An ultrasound-guided techniques would allow placement of the needle without depending on external landmarks. Methods: Fourteen pelvic specimens were isolated from mature horses. A 20 cm bent spinal needle was positioned with ultrasonographic guidance under both iliac wings aiming for SI joints using 5 approaches: cranial, craniomedial, medial and 2 caudal approac...
Théon AP, Pascoe JR.One hundred and fifteen horses with periocular tumours were treated with iridium-192 interstitial brachytherapy. Tumours included squamous cell carcinomas (n = 52) and sarcoids (n = 63). All horses were scheduled to receive 60 Gy (minimal tumour dose) given at a low dose rate (0.034 +/- 0.010 Gy/h). The mean and median follow-up times to last contact or death were 24 and 16 months, respectively. Chronic radiation reactions included palpebral fibrosis (10.4%), cataract (7.8%), keratitis and corneal ulceration (6.9%). Cosmetic changes included permanent epilation (21.7%) and hair dyspigmentation...
Ringmark S, Jansson A, Lindholm A, Hedenström U, Roepstorff L.The aim of this study was to document effects of two high-intensity training regimes on horse health. Sixteen Standardbred horses in training from September as 1-year-olds with the goal to race as 3-year-olds were used in a 2.5 year study. Horses were trained in either a control training program (C-group) or in a program with 30% reduced high intensity distance compared to the C-group (R-group). Clinical examinations were performed nine times. Locomotion asymmetry was registered with a sensor-based system 17 times. There was no difference in health scores, locomotion asymmetry or veterinary tr...
Ducheyne KD, Rizzo M, Cuervo-Arango J, Claes A, Daels PF, Stout TAE, de Ruijter-Villani M.Invitro embryo production is an increasingly popular means of breeding horses. However, success is limited by a high incidence of early embryo loss. Although there are various possible causes of pregnancy failure, chromosomal abnormalities, including aneuploidy, are important potential contributors. This study evaluated the frequency of micronucleus formation as a proxy for aneuploidy in invitro-produced (IVP) and invivo-derived horse blastocysts. Associations between IVP embryo morphology, frequency of nuclear abnormalities and the likelihood of pregnancy were investigated. IVP blastocysts ex...
Bertone AL.Exuberant granulation tissue is common in large, lower limb wounds of horses, particularly horses of large body size. Methods of control include chemical cautery, cryogenic surgery, and surgical resection. Surgical resection is preferred because it is easy to perform, provides tissue for histologic evaluation, and preserves the epithelial margin. Effective treatments to prevent the formation of granulation tissue include leaving granulating wounds open to the air or, possibly, bandaging with topical steroids. Bandaging or casting may promote exuberant granulation tissue in wounds in which it h...
Smith MA, Walmsley JP, Phillips TJ, Pinchbeck GL, Booth TM, Greet TR, Richardson DW, Ross MW, Schramme MC, Singer ER, Smith RK, Clegg PD.Subchondral cystic lesions of the medial femoral condyle (SCMFC) are well documented in horses < or =3 years; arthroscopic debridement or enucleation of the cyst is currently the surgical treatment of choice. However, studies of occurence and outcome following surgery in older horses are lacking. Objective: To identify factors important in outcome for horses with SCMFC treated by arthroscopic debridement. Objective: Age of horse at presentation has a significant influence on return to work following arthroscopic treatment for SCMFC. Clinical and diagnostic findings are also significant with re...
Keen JA.Pathological bradyarrhythmia is rare in horses but should be especially considered when presented with a horse that has signs consistent with episodic weakness or collapse. This paper reviews the literature describing our current knowledge of, and possible mechanisms causing, clinically significant bradyarrhythmia in horses.
Van Steenkiste G, Delhaas T, Hermans B, Vera L, Decloedt A, van Loon G.In human cardiology, the anatomical origin of atrial premature depolarizations (APDs) is derived from P wave characteristics on a 12-lead electrocardiogram (ECG) and from vectorcardiography (VCG). The objective of this study is to differentiate between anatomical locations of APDs and to differentiate APDs from sinus rhythm (SR) based upon VCG characteristics in seven horses without cardiovascular disease. A 12-lead ECG was recorded under general anaesthesia while endomyocardial atrial pacing was performed (800−1000 ms cycle length) at the left atrial free wall and septum, right atrial free ...
Schwarzwald CC, Kedo M, Birkmann K, Hamlin RL.To investigate the relationship of heart rate (HR) and ECG time intervals to body weight (BWT) in healthy horses and ponies. We hypothesized that HR and ECG time intervals are related to BWT. Methods: 250 healthy horses of >30 breeds; 5.5 (1-30) y [median (range)]; 479 (46-1018) kg. Methods: Prospective study. Standard base-apex ECGs were recorded while the horses were standing quietly in a box stall. Mean HR over 15 s was calculated and RR interval, PQ interval, QRS duration, and QT interval were measured by a single observer.QT was corrected for differences in heart rate using Fridericia'...
Butudom P, Barnes DJ, Davis MW, Nielsen BD, Eberhart SW, Schott HC.To determine whether temperature of rehydration fluid influences voluntary rehydration by horses, six 2-3-year-old horses were dehydrated (4-5% body weight loss) by a combination of furosemide administration and 30 km of treadmill exercise. For the initial 5 min following exercise, horses were offered a 0.9% NaCl solution at 10, 20, or 30 degrees C. Subsequently, after washing and cooling out, voluntary intake of water at 10, 20, or 30 degrees C from 20 to 60 min after exercise was measured. Fluid intake (FI) during the first 5 min of recovery was 9.8+/-2.5,12.3+/-2.1 and 9.7+/-2.0L (p>0.05) f...
Tanaka Y, Taniyama H, Tsunoda N, Shinbo H, Nagamine N, Nambo Y, Nagata S, Watanabe G, Herath CB, Groome NP, Taya K.Immunolocalization of the inhibin (a) and inhibin/activin (beta3A and betaB) subunit proteins in equine fetal testes was investigated to determine the ability of the fetal testis to produce inhibins at 120, 150, 200, and 250 days of gestation. In addition, concentrations of immunoreactive (ir)-inhibin, inhibin pro-aC, and inhibin A in both the maternal and fetal circulation were measured. It was found that plasma concentrations of ir-inhibin, inhibin pro-alphaC, and inhibin A were much higher (P < .05) in the fetal than in the maternal circulation at any stage of gestation examined. Similar...
Tsuzuki N, Sasaki N, Kusano K, Endo Y, Torisu S.Oxidative stress has been reported to occur during surgery. It is important to reduce intraoperative oxidative stress to improve the postoperative prognosis. However, there are no reports regarding oxidative stress related to surgery in horses. In the present study, we measured pre and postsurgical diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP); the oxidative stress index (OSI) was then calculated (OSI=d-ROMs/BAP × 100). d-ROMs were not significantly different between the pre and postsurgical periods. However, BAP significantly decreased after surgery ...
Hart KA, Barton MH, Vandenplas ML, Hurley DJ.Low-dose hydrocortisone (LDHC) therapy modulates inflammatory responses in adults and improves outcomes in some septic adults and neonates, but its immunologic effects have not been evaluated in neonates. The objective of this study was to evaluate effects of LDHC therapy on ex vivo immune function in neonatal horses (foals). We hypothesized that LDHC treatment would dampen proinflammatory responses without impairing neutrophil function. Hydrocortisone (1.3 mg/kg/d i.v.) was administered to foals in a tapering 3.5 d course. Peripheral blood leukocytes were collected from foals before, during, ...
Rakesh V, Ducharme NG, Cheetham J, Datta AK, Pease AP.The necessary degree of arytenoid cartilage abduction (ACA) to restore airway patency at maximal exercise has not been determined. Objective: Use computational fluid dynamics modelling to measure the effects of different degrees of ACA on upper airway characteristics of horses during exercise. Objective: Maximal ACA by laryngoplasty is necessary to restore normal peak airflow and pressure in Thoroughbred racehorses with laryngeal hemiplegia. Methods: The upper airway was modeled with the left arytenoid in 3 different positions: maximal abduction; 88% cross-sectional area of the rima glottis; a...
Lapointe JM, Lavoie JP, Vrins AA.Effects of triamcinolone acetonide (TA) on pulmonary function, bronchoalveolar lavage cytologic features and serum cortisol concentration, were studied in 5 control horses and 5 horses with chronic obstructive pulmonary disease (COPD). In experiment 1, horses were brought in from pasture 3 weeks before administration of 1 injection of TA (0.09 mg/kg of body weight, IM), and were stabled in dusty conditions throughout the experimental period. Measurements of respiratory rate (f), tidal volume, minute ventilation, expiratory-to-inspiratory time ratio, maximal change in transpulmonary pressure (d...
