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.
Morris L.Advanced artificial insemination techniques, such as deep uterine,hysteroscopic, oviductal, and intrafollicular insemination, are described in the context of the different types of spermatozoa that are now available for insemination, including fresh, chilled, frozen,sex-sorted, and epididymal spermatozoa. The implementation of these new technologies answers and poses questions about the interactions of sperm and oocytes in vivo.
Yuan Z, Philbey AW, Gault EA, Campo MS, Nasir L.Papillomaviruses are normally strictly species-specific and even under experimental conditions do not usually infect any other host than the natural host. The only documented reports of natural papillomavirus cross-species infection are of BPV-1/BPV-2, which can infect horses and induce equine sarcoids. BPV DNA has not been detected in non-sarcoid equine tumours or equine papillomas, but its presence has been reported in some cases of equine dermatitis. In the present study, we show that equine inflammatory skin conditions harbour episomal circular double stranded BPV-1 genomes, with copy numb...
Carnevale EM.Vitrification can be used successfully to cryopreserve equine embryos. Embryos for vitrification should be collected from donor mares' uteri when they are 300 mm or less in diameter, however,and at the morula or early blastocyst stage of development. No special equipment is required for vitrification; the straw containing the embryo is exposed to vapor for 1 minute before plunging it into liquid nitrogen. Warming of the straw requires no special equipment,and the embryo can be transferred directly from the straw into a recipient's uterus. Vitrification has been repeatedly successful when the p...
Loomis PR.Clinical reproduction in the horse more closely parallels human clinical reproduction than in other domestic farm animals. Horse breeders rarely include fertility as a selection criterion when making mating decisions; in most breeds, there is no licensing or approval of stallions. This has led to a significant number of stallions in the breeding pool that possess desirable performance traits but are subfertile for a variety of reasons, some of them genetically transmitted between generations. Therefore, semen characteristics can vary greatly among stallions within the breeding population. A ch...
Hendrickson D.Laparoscopic surgery has become commonplace in the field of equine urogenital surgery. As with most surgical procedures, the limiting factors in developing new surgical techniques are limited to the patient size and demeanor, the skills of the surgeon, and the available equipment. Some of the greatest benefits of laparoscopic surgery in the horse include better visualization of the important structures; tension-free amputation of the testes or ovaries,which generally leads to less postoperative pain; and the ability to evaluate the transected stump carefully to make sure there is no hemorrhage...
Bucca S.Identification of a compromised pregnancy in the mare requires the exhaustive collection of a database that includes past and recent reproductive and medical histories and a variety of parameters indicating fetal distress and possibly suggesting neonatal compromise.Judicious interpretation of findings and serial recording of data throughout gestation may help in the early detection of abnormal fetomaternal exchange pathways. Some sources of compromise may be identified, and the impact on fetomaternal well-being maybe calculated. Appropriate preventive or corrective measures may then be impleme...
Carnevale EM, Maclellan LJ.Assisted reproductive techniques have been developed to obtain pregnancies from subfertile mares and stallions and to salvage gametes after death. In recent years, these procedures have been used for clinical cases with repeated success. Although new developments occur, the basis for the success and future development of assisted reproductive techniques is our ability to collect and handle the equine oocyte successfully. This article focuses on important clinical aspects of oocyte collection and evaluation and briefly discusses the clinical use of assisted reproductive procedures in the horse....
Kútvölgyi G, Stefler J, Kovács A.A simple trypan blue-neutral red-Giemsa staining procedure for simultaneous evaluation of acrosome, sperm head, and tail membrane integrity and morphology has been used to evaluate equine spermatozoa. Some special characteristics and problems have arisen in evaluating stallion semen. One problem was the differentiation of intact vs. damaged sperm tails primarily in frozen and thawed samples. After freezing and thawing, a high percentage of spermatozoa with an unstained head and stained tail were observed. These cells are considered immotile. Therefore, unambiguous differentiation of intact vs....
Troedsson MH.Endometritis is a common cause of infertility in broodmares. In the past, the condition was believed to be exclusively the result of bacterial contamination of the uterus. Treatment strategies were focused on preventing bacteria from entering the uterus and on treating mares with signs of endometritis with antibiotics. More recent research on uterine defense mechanisms has increased our understanding of the pathophysiology of equine endometritis. Additional causative agents have been identified, and we have learned to separate uterine infections and a physiologic breeding-induced endometritis ...
Veeramachaneni DN, Moeller CL, Sawyer HR.Conventional light microscopic evaluation of a seminal ejaculate does not fully avail potential indicators of functional impairment in spermatozoal organelles. The technique of critical quantitative evaluation of morphologic features of individual structural components of spermatozoa at a light microscopic level in conjunction with critical qualitative evaluation of spermatozoal organelles at an ultrastructural level, as described in this article, is a valuable clinical tool. Compared with a battery of sperm function assays used in human andrology clinics, this relatively less expensive and si...
Hinrichs K.Equine cloning is now in use as a clinical technique. It is available commercially, and its efficiency seems to be increasing. The foals produced by cloning may differ in some phenotypic and behavioral traits from the original animal but should produce offspring that reflect those that the original donor animal would have produced. This is especially true in the case of male animals, where the mitochondrial DNA is not passed to the progeny. Results of pregnancies due in 2006 should add significantly to our understanding of the factors affecting production of viable cloned foals and of the simi...
Bruemmer JE.The ability to harvest and preserve epididymal sperm from a stallion after simple elective castration, a catastrophic injury, or severe acute illness and subsequent death has been realized, allowing for the preservation of genetics that would have been lost otherwise.Currently, the care taken to collect the testes and epididymides properly, coupled with proper packaging and shipping, could make the greatest contribution to salvaging viable sperm. As advances in assisted reproductive techniques continue, more offspring may be obtained from stored epididymal sperm from valuable stallions.
Wolfsdorf KE.Methods to manage twins after fixation include natural reduction,dietary reduction, transvaginal ultrasound-guided aspiration,surgical removal, craniocervical dislocation, and transabdominal ultrasound-guided injection. Of these, results have been inconsistent with regard to producing a single healthy foal, except for craniocervical dislocation. This new technique enables the twin to be reduced before complete placenta formation has occurred, allowing the remaining fetus to use the entire endometrial surface and grow to its full potential.
McCue PM, Roser JF, Munro CJ, Liu IK, Lasley BL.The granulosa cell tumor is the most common ovarian tumor in mares. A clinical diagnosis can be made based on the presence ofa unilaterally enlarged ovary and a small inactive contralateral ovary. Endocrine testing may be beneficial to confirm a diagnosis. Surgical removal of the tumor eliminates the adverse effect on pituitary function and results in resumption of follicular development and ovulation in the opposite ovary over time.
Macpherson ML.Equine placentitis is a complex disease that has devastating consequences for horse owners. Placentitis is a significant cause of foal loss annually. Prompt diagnosis and treatment of the disease are paramount for survival of the affected neonate. This article discusses current information on pathogenesis of the disease as well as diagnostic and therapeutic options.
Hendrickson D.Laparoscopic surgery has become commonplace in the field of equine urogenital surgery. As with most surgical procedures, the limiting factors in developing new surgical techniques are limited to the patient size and demeanor, the skills of the surgeon, and the available equipment. Some of the greatest benefits of laparoscopic surgery in the horse include better visualization of the important structures; tension-free amputation of the testes or ovaries,which generally leads to less postoperative pain; and the ability to evaluate the transected stump carefully to make sure there is no hemorrhage...
Minervini F, Giannoccaro A, Fornelli F, Dell'Aquila ME, Minoia P, Visconti A.The mycotoxin zearalenone (ZEA) and its derivatives, alpha and beta-zearalenol (alpha and beta-ZOL), synthesized by genera Fusarium, often occur as contaminants in cereal grains and animal feeds. The importance of ZEA on reproductive disorders is well known in domestic animals species, particularly in swine and cattle. In the horse, limited data are available to date on the influence of dietary exposure to ZEA on reproductive health and on its in vitro effects on reproductive cells. The aim of this study was to evaluate the effects of ZEA and its derivatives, alpha and beta-ZOL, on granulosa c...
Gulati BR, Deepa R, Singh BK, Rao CD.Rotaviruses causing severe diarrhea in foals in two organized farms in northern India, during the period from 2003 to 2005, were characterized by electropherotyping, serotyping, and sequence analysis of the genes encoding the outer capsid proteins. Of 137 specimens, 47 (34.31%) were positive for rotavirus and exhibited at least five different electropherotypes (E), E1 to E5. Strains belonging to different electropherotypes exhibited either a different serotype/genotype specificity or a lack of reactivity to typing monoclonal antibodies (MAbs) used in this study. Strains belonging to E1, E2, an...
Choi KS, Ko YJ, Nah JJ, Kim YJ, Kang SY, Yoon KJ, Joo YS.A rapid immunoassay for detecting and quantifying West Nile virus (WNV)-neutralizing antibodies in sera was developed as an alternative to the plaque reduction neutralization test (PRNT), the gold standard test for WNV. The assay is a competitive, enzyme-linked immunosorbent assay using neutralizing monoclonal antibody 5E8 (NT-ELISA). A cutoff percent inhibition (PI) value of 35% (mean PI plus 3 standard deviations), with a specificity of 99%, was established based on analysis of 246 serum samples from horses free of WNV. The NT-ELISA detected neutralizing antibodies in all sera collected 7 or...
Franci P, Leece EA, Brearley JC.Patient positioning and long anaesthetic duration required for magnetic resonance imaging (MRI) may result in a higher frequency of post anaesthetic myopathy/neuropathy syndrome (PAMNS) as compared to horses undergoing anaesthesia for surgery. Objective: Equine anaesthesia for MRI is associated with a higher frequency of PAMNS than anaesthesia for nonemergency, nonabdominal surgery. Methods: Anaesthetic and medical records of horses (n = 633) undergoing MRI or surgery between January 2001 and January 2005 (inclusive), were reviewed. Information obtained included patient details (breed, sex, ag...
Knox PM, Watkins JP.A method for proximal interphalangeal joint (PIP joint) arthrodesis that provides a stable fixation and minimal duration of cast support is evaluated retrospectively. Objective: Evaluate the clinical use of a combined plate-screw method for PIP joint arthrodesis in a large number of horses. Methods: The records of 53 horses undergoing PIP joint arthrodesis were reviewed. Arthrodesis was performed with a dorsally placed 3-, 4- or 5-hole narrow dynamic compression plate (DCP) with 2 transarticular cortex screws placed in lag fashion either side of the plate. Subject details, clinical presentatio...
Varcoe-Cocks K, Sagar KN, Jeffcott LB, McGowan CM.Despite the prevalence of orthopaedic injuries to horses, there is no objective means of quantifying the intensity of musculoskeletal pain. Objective: Mechanical nociceptive thresholds (MNT) can be measured repeatably by pressure algometry in horses and MNTs are correlated with both severity of clinical signs and subjective scores of muscle pain on palpation in horses with suspected sacroiliac dysfunction (SID). Methods: The technique of pressure algometry and its repeatability was tested at 4 anatomical sites on either side of the thoracolumbar and pelvic region in 12 Thoroughbreds in trainin...
Taylor SE, Weaver MP, Pitsillides AA, Wheeler BT, Wheeler-Jones CP, Shaw DJ, Smith RK.Quantification of cartilage oligomeric matrix protein (COMP) levels within synovial fluid from the tarsometatarsal joint has not previously been reported and an effective synovial fluid marker would allow monitoring of disease progression and treatment. Objective: To quantify levels of COMP and hyaluronan (HA) in synovial fluid from the tarsometatarsal joint, identify differences in levels from horses with osteoarthritis (OA) of the tarsometatarsal joint compared to a control population and to correlate levels with radiographic changes in horses with OA. Methods: Synovial fluid was collected f...
Wilsher S, Allen WR.There is a paucity of information on factors that influence placental development in the horse. Objective: Changes in nutrition, particularly around the time of proliferative placental growth, can affect development of the placenta and fetal growth. Objective: To investigate the effects of 2 planes of nutrition and an unforeseen infection-mediated nutritional insult on placental and fetal development in the mare. Methods: Twenty maiden Thoroughbred fillies, age 3 or 4 years, mated to one Thoroughbred stallion, were maintained on either High or Moderate food intake throughout pregnancy. In mid-...
Cesarini C, Hamilton E, Picandet V, Lavoie JP.Theophylline has been shown to have corticosteroid-sparing effects for the treatment of human asthma. A similar effect, if present in horses, would allow diminishing the dose of corticosteroids administered to equine patients with inflammatory airway diseases. Objective: To evaluate whether theophylline potentiates the effects of a low dose of dexamethasone when treating horses with recurrent airway obstruction (RAO). Objective: Theophylline has steroid-sparing effects in horses with RAO. Methods: Ten mature mixed breed horses in clinical exacerbation of RAO were studied. Using an incomplete c...
Camargo FC, Robinson NE, Berney C, Eberhart S, Baker S, DeTolve P, Derksen FJ, Harkins JD, Lehner AF, Tobin T.Trimetoquinol (TMQ) is a potent beta-adrenoceptor agonist bronchodilator used in human medicine but has not been evaluated for potential use as a therapeutic agent for horses with 'heaves'. Objective: To assess the pharmacodynamics of TMQ in horses with 'heaves' to determine potential therapeutic effects. Methods: Increasing doses of TMQ were administered to horses with 'heaves' by i.v. and intratracheal (i.t.) routes. Doses ranged 0.001-0.2 microg/kg bwt i.v. and 0.01-2 microg/kg bwt i.t. Cardiac and airways effects were assessed by measurement of heart rate (HR) and maximal change in pleural...
Southwood LL, Lindermann J, Zarucco L, Driessen B, Olander H, Habecker P, Birks EK, Frisbie DD.Growth factors (GF) are important for maintenance and repair of intestinal mucosal structure and function, but there have been no studies investigating growth factor (GF) or growth factor receptor (GF-R) mRNA expression in the intestine of horses with large colon volvulus (LCV). Objective: (1) To determine mRNA expression for epidermal growth factor (EGF), EGF receptor (EGF-R), insulin-like growth factor-I (IGF), IGF receptor (IGF-R), vascular endothelial growth factor (VEGF) and VEGF receptor (VEGF-R) in the intestine of horses with an LCV compared to normal intestine. (2) To measure the corr...
Morris S, Kelleman AA, Stawicki RJ, Hansen PJ, Sheerin PC, Sheerin BR, Paccamonti DL, LeBlanc MM.Transrectal ultrasonography of the caudal uterus and a progestin profile were evaluated for accuracy in identifying mares with feto-placental compromise in a model of placentitis. Twenty-two pregnant ponies were divided into four groups: (1) control mares (n=5); (2) instrumented controls (n=2); (3) instrumented inoculated mares (n=11); (4) inoculated mares (n=4). Mares in Groups 3 and 4 were inoculated with Streptococcus equi subsp. zooepidemicus. Maternal plasma progestins, vulvar discharge, mammary gland development, combined thickness of the uterus and placenta (CTUP) and placental separati...
Bischofberger AS, Konar M, Ohlerth S, Geyer H, Lang J, Ueltschi G, Lischer CJ.The diagnosis of lameness caused by proximal metacarpal and metatarsal pain can be challenging. Magnetic resonance imaging (MRI) offers the possibility for further diagnosis but there have been no studies on the normal MRI appearance of the origin of the suspensory ligament (OSL) in conjunction with ultrasonography and histology. Objective: To describe the MRI appearance of the OSL in fore- and hindlimbs of sound horses and compare it to the ultrasonographic and histological appearance. The findings can be used as reference values to recognise pathology in the OSL. Methods: The OSL in the fore...
Robles M, Hammer C, Staniar B, Chavatte-Palmer P.Forage availability should cover most needs for mares bred during spring and summer. Out-of-season breeding, lack of access to pasture, or good quality forage calls for nutritional supplementation. Current evaluations of broodmare needs are based on fetoplacental tissue requirements, but do not consider endocrine changes or that the maternal diet quality affects long-term foal health. This article reviews pregnant mares' current nutritional recommendations. Secondly, fetoplacental developmental stages during gestation are outlined, defining critical periods in the context of the developmental ...
Lapjit C, Charoenchanikran P, Petchkaew P, Sukpipattanamongkol S, Yodsheewan R, Theerapan W, Chanda M.The fetlock joint is a high mobility structure that accommodates enormous loading during locomotion. An injury of the superficial constituent such as subtendinous bursitis may occur due to repeated trauma. An 8-year old school riding horse was presented with dorsomedial distension in the left hindlimb fetlock region. The lesion was noted following routine exercise. The horse demonstrated no lameness and a negative response to the fetlock flexion test. Radiographic findings revealed a smooth surface cortical thickening on the medial aspect of the distal third metatarsal bone. Furthermore, the u...
Tharasanit T, Colenbrander B, Bevers MM, Stout TA.The only gonadotrophin preparation shown to stimulate commercially useful multiple ovulation in mares is equine pituitary extract (EPE); even then, the low and inconsistent ovulatory response has been ascribed to the variable, but high, LH content. This study investigated the effects of an LH-free FSH preparation, recombinant human follicle stimulating hormone (rhFSH), on follicle development, ovulation and embryo production in mares. Five mares were treated twice-daily with 450 i.u. rhFSH starting on day 6 after ovulation, coincident with PGF(2alpha) analogue administration; five control mare...
Martin RG, McMeniman NP, Dowsett KF.Six lactating mares were fed either a low protein diet or the same diet with added urea ad libitum over 71 days. The quantity consumed by the mares, milk intakes of their foals, milk composition, plasma urea nitrogen (PUN), mare liveweight changes and foal growth rates were measured. The mares were unable to consume sufficient quantities of either diet to meet their nitrogen requirements and all lost weight. Adding urea to the diet significantly increased PUN in mares and foals, raised urea concentrations in the milk, decreased the mares' feed intake and significantly increased their weight lo...
Bernard WV, Williams D, Tuttle PA, Pierce S.A Thoroughbred foal that was born after 305 days of gestation was referred 6 hours after birth. On initial examination, the foal was alert, but weak and unable to stand. Heart rate was 150 beats/min, respiratory rate was 48 breaths/min, and rectal temperature was 33 C. Leukocytosis was detected (26,000 WBC/microliters). Dysuria and passage of red urine was observed approximately 30 hours after admission. Urine collected by free catch had a 3+ reaction for blood on dipstick analysis. Examination of Warthin Starry-stained sections of allantochorion revealed organisms morphologically characterist...
Cox VS, Weber AF, de Lima A.A complete left cranial vena cava (LCVC) was found in a normal horse. The LCVC was well developed, but there was a complete absence of the right cranial vena cava. The azygous vein was normally distributed on the right side of the thoracic vertebral bodies but passed ventral to the aortic arch to empty into the cranial vena cava on the left close to the origin of the aortic arch. The LCVC passed over the dorsal aspect of the left atrium to reach the coronary sulcus on the caudal aspect of the heart. The LCVC opened into the right atrium via a 5 cm diameter orifice (orifice of coronary sinus). ...
Del Piero F.Two 5-year-old grade male horses presented with epiphora, rhinorrhea, conjunctival and nasal mucosal hyperemia, and dorsal and thoracic macropapular rash. Skin biopsies were collected from the affected areas, and serial sections were evaluated following hematoxylin and eosin and immunoperoxidase histochemistry staining by using a murine monoclonal antibody of the immunoglobulin G2A isotype recognizing the 30-kDa membrane protein of equine arteritis virus (EAV). In both horses, lesions consisted of mild to moderate diffuse superficial dermal edema and vasculitis with mild perivascular lymphocyt...
Seahorn TL, Sams AE, Honnas CM, Schmitz DG, McMullan WC.Ultrasonography was used to confirm the tentative diagnosis of keratoma in a horse admitted for chronic progressive lameness. A definitive diagnosis of keratoma traditionally has been diagnosed by history, clinical findings, and radiographic evaluation. Confirmation of the keratoma by use of ultrasonography facilitated the formulation of a treatment plan that resolved the condition.
Held JP, Adair S, McGavin MD, Adams WH, Toal R, Henton J.Two stallions had unilateral bacterial epididymitis attributable to S zooepidemicus infection. Diagnosis was based on bacterial isolation, WBC in the semen, higher than normal blood fibrinogen concentration, and leukocytosis with regenerative left shift. One horse had high seminal pH. Ultrasonography of the involved epididymides revealed changes consistent with the appearance of abnormal accumulation of exudate in the tail of the epididymis. Treatment included unilateral orchiectomy and antibiotic administration. In stallion 1, the infection persisted despite treatment. Treatment result was no...
Joubert P, Cordeau ME, Boyer A, Silversides DW, Lavoie JP.Heaves, also known as recurrent airway obstruction, is a common condition of horses characterised by pulmonary neutrophilia and reversible airway obstruction. This study evaluated the role of neutrophils in producing cytokines and chemokines that might be involved in the recruitment and activation of inflammatory cells in horses with heaves. Peripheral neutrophils were isolated from heaves-affected (n = 9) and control (n = 4) horses before and after 5 h of natural inhalation challenge. Expression of mRNA of two pro-inflammatory cytokines, tumour necrosis factor (TNF)-alpha and interleukin (IL)...
Engiles JB.The etiopathogenesis of laminitis is complex and involves multiple tissue types. It may be initiated by biomechanical, traumatic, inflammatory, vascular, toxic, and metabolic factors. Although histopathologic changes occurring within the lamellae of experimental models of laminitis are well described and reported, histopathologic changes occurring in the distal phalanx are not, even though gross and radiographic evidence of disease are often apparent and bony lesions could be considered a significant source of pain. Recent scientific evidence indicates that the microenvironment of bone is an i...
Takai S, Sengee S, Madarame H, Hatori F, Yasuoka K, Ochirel E, Sasaki Y, Kakuda T, Tsubaki S, Bandi N, Sodnomdarjaa R.In native Mongolian horses, the incidence and distribution of Rhodococcus equi are poorly understood. One hundred and fourteen equine fecal samples and 71 soil samples were collected from the camp sites of 26 nomadic families located in three areas less than 100 km from Ulaanbaatar, Mongolia. Five fecal samples were also collected from foals of Przewalski's Horses introduced into the Hustai National Park, Mongolia. No R. equi was isolated from the Mongolian horses or the soil samples. However, three colonies of R. equi were isolated from two fecal samples collected from foals of Przewalski's H...
Crandall A, Hopster K, Grove A, Levine D.In horses undergoing castration, direct comparison of intratesticular lidocaine vs mepivacaine as analgesic adjuncts has not yet been analysed. Objective: To compare the effects of intratesticular lidocaine and mepivacaine during equine castration using the Henderson drill under total intravenous anesthesia. Methods: Randomised, double-blinded clinical study. Methods: Thirty-four stallions were anaesthetised using xylazine-ketamine and randomly selected to receive 10 mL either lidocaine or mepivacaine injected into each testicle. Both surgeon and anaesthetist were blinded to the selected trea...
Anderson ST, Kidd LJ, Barton AJ, Greer RM.Breeding mares typically foal yearly. Little is known about the dynamics of maternal bone stores during gestation and lactation, the timing of any maternal bone mobilisation, re-accretion post-foaling, or the dynamics of bone metabolism in foals. We measured serum osteocalcin (OC) and serum pyridinoline (PYD) concentrations in 18 mares monthly from 6months gestation to foaling, and in both mares and foals for 4months after birth. From 6 to 11months of gestation, there was no change in mean monthly OC. Serum PYD increased between 7months gestation and foaling. After foaling, mean serum OC was l...
Ott EA, Asquith RL.Forty-six Thoroughbred and Quarter Horse yearlings were used in two experiments to evaluate the effect of mineral supplementation on growth and skeletal development. In the first experiment, concentrate and bermuda-grass hay diets providing 2.82 Mcal DE/kg (estimated), 13.0% CP, .62% Ca and .43% P on a DM basis were supplemented with trace minerals (TM) by adding 0, .5 or 1.0% TM premix to the concentrate. The TM content of the three diets (concentrate and hay) in mg/kg DM were: Fe 150, 162 and 176; Mn 56, 60 and 64; Zn 36, 53 and 69; and Cu 7, 8 and 11 for the low, medium and high TM levels, ...
Wilke M, Nixon AJ, Malark J, Myhre G.To determine clinical and radiographic findings, treatment, and outcome of horses with fractures of the palmar aspect of the radial carpal bone, with or without concurrent fractures of the palmar surfaces of the other carpal bones. Methods: Retrospective study. Methods: 10 horses. Methods: Medical records were reviewed to obtain information on history, signalment, clinical and radiographic findings, treatment, and outcome. Follow-up information was gathered from owners and referring veterinarians. Results: 7 horses became lame after recovery from general anesthesia for treatment of an unrelate...
Rehbein S, Holste JE, Doucet MY, Fenger C, Paul AJ, Reinemeyer CR, Smith LL, Yoon S, Marley SE.The efficacy of an oral formulation of ivermectin plus praziquantel in the reduction of nematode and cestode egg counts in horses was assessed in 273 horses under field conditions at 15 sites in North America (n = 6) and Europe (n = 9). Horses were confirmed by fecal examination to have natural infections of strongyles (100%) and tapeworms (76%). Replicates of four horses were formed at each site, and in each replicate three animals received ivermectin (0.2 mg/kg body weight) plus praziquantel (1 mg/kg body weight) oral paste and one animal remained untreated or received vehicle paste. Fecal s...
Esteller-Vico A, Liu IK, Couto S.Vascular degeneration is present in endometrial vessels of multiparous aged mares. The lesions associated with vascular degeneration consist of enlargement, duplication and splitting of the membrana elastica interna and perivascular deposits of elastin. However, there are no similar data available for deep myometrial vessels and the vascular layer. The objectives of the present study were to characterize the status of vasculature in full-thickness uterine necropsy samples and to correlate these findings to endometrial grade, age, and parity. Elastosis was present in myometrial vessels, as well...
Loy RG, Swan SM.Progesterone in oil solution injected into mares intramuscularly in midcycle blocked estrus and ovulation at levels of 100 mg. per day or higher. Fifty milligrams per day prevented estrus but not ovulation. The interval from end of treatment to estrus appeared to depend upon dosage, and the effects on subsequent cyclic patterns were confounded by season of the year. Neither 50 nor 100 mg. per day stopped estrus or blocked ovulation when treatment was started on day 1 of estrus. Injection of 100 mg. per day of progesterone in oil delayed postpartum estrus and ovulation, but 50 mg. per day did n...
Ainsworth DM, Smith CA, Eicker SW, Ducharme NG, Henderson KS, Snedden K, Dempsey JA.In exercising quadrupeds, limb movement is often coupled with breathing frequency. This finding has lead some investigators to conclude that locomotory forces, associated with foot plant, abdominal visceral displacements or lumbo-sacral flexion, are the primary determinants of airflow generation. Analysis of respiratory muscle electrical activation (EMG) and contraction profiles in chronically instrumented dogs and horses, along with measurements of esophageal pressure (Pes) changes and limb movements, provide evidence that each breath during the exercise hyperpnea is determined by respiratory...
Claerhoudt S, Bergman EH, van der Veen H, Vanderperren K, Raes EV, Saunders JH.The morphological features of the distal border synovial invaginations (SI) of the distal sesamoid bone (DSB) in horses were described by the use of computed tomography (CT). Transverse CT images were obtained on 50 cadaver forefeet from 25 Warmblood horses. Dorsal and sagittal planes were reformatted. The CT images allowed the evaluation of the number, shape, depth of penetration and direction of the SI into the bone. The total number of SI was 295 (mean 5.9). The number of invaginations in a particular DSB ranged from 3 (n = 3), 4 (n = 6), 5 (n = 11), 6 (n = 12), 7 (n = 13), 8 (n = 3), 9 (n ...
Lyda RO, Hall JR, Kirkpatrick JF.Fifteen captive wild mares (Equus caballus) were treated with porcine zona pellucida contraceptive vaccine and either Freund's Complete Adjuvant (n = 7) or Freund's Modified Adjuvant (n = 8). All mares received a booster inoculation of porcine zona pellucida plus Freund's Incomplete Adjuvant a month later. Anti-porcine zona pellucida antibodies were measured over 10 mo following the initial inoculation. There were no significant differences in antibody titers at any point during the 10 mo, and seven of the eight mares in the Freund's Modified Adjuvant group were above the 60% level at the end ...
Steward KF, Robinson C, Maskell DJ, Nenci C, Waller AS.The Gram-positive bacterium subspecies () is the causative agent of strangles, among the most frequently diagnosed infectious diseases of horses worldwide. Genome analysis of strain 4047 (4047) identified a putative operon, Fim1, with similarity to the pilus loci of other Gram-positive bacteria. The Fim1 locus was present in all strains of and its close relative subspecies () that have been studied to date. In this study we provide evidence that the putative structural pilus proteins, SEQ_0936 and CNE, are produced on the cell surface during growth and infection. Although the proteins ...
Nitzsche AM, Fey K, Büttner K, Gröf M, Staszyk C.Pituitary pars intermedia dysfunction (PPID) is a common neurodegenerative disease mainly in horses older than 15 years. The domestic equine population is following the same demographic change as that seen in humans; it is aging and veterinarians are asked to attend to geriatric horses more frequently. Common problems seen regularly in older equines are dental disorders and especially periodontal disease. As a systemic and endocrine disease, associated with delayed wound healing and impaired immune function, PPID should be considered before major dental treatment in aged equines is started. Po...
Sahu SP, Wool S, Breese SS.In uterine or cervical specimens obtained from pony mares infected with streptomycin-resistant contagious equine metritis bacteria, several colonies of the bacteria which differed in morphologic characteristics were recognized during their primary isolation on Eugon chocolate agar and tryptose chocolate agar plates. The differences were usually not observed until plates were incubated 10 to 15 days. On Eugon chocolate agar plates, smooth colony, sandy colony with rings, and colony with blebs were recognized. On tryptose chocolate agar plates, only a round smooth convex colony was observed. By ...
Pilsworth RC, Webbon PM.Five horses, all two year old Thoroughbreds, presented with acute onset hindlimb lameness following moderate to fast exercise. The use of a hand-held scintillation detector after Tc99 MDP injection greatly aided the diagnosis of tibial stress fractures in these horses. Radiological findings were subtle, involving only periosteal new bone and callus at the fracture site. In two cases this took several weeks to develop but in three others was present at the onset of lameness, indicating insidious pre-fracture bone pathology. The site of the most obvious radiological signs was constant in all fiv...
Spoormakers TJP, Bergmann W, Veraa S, van Weeren PR, Brommer H.To verify the existence of intertransverse joints (ITJs) in young foals. 11 warmblood foals. Postmortem examination of the lumbar area in foals < 200 days old using CT, MRI, dissection, and histomorphology. Data were analyzed with descriptive statistics. Age of foals varied between 1 and 200 days (median, 11 days). Ten foals had 6 lumbar (L) vertebrae, and 1 foal had 5. All 11 foals, irrespective of age, had ITJs between the first sacral and last lumbar vertebrae and between the last and second-to-last lumbar vertebrae. In 6 foals (all with 6 L vertebrae), ITJs also existed between the four...
Denkhaus M, Van Amstel S.Non-commercial, endotoxin positive, intravenous fluids as well as a commercially available intravenous fluid were given to clinically normal horses. Endotoxin-positive fluids caused clinical signs attributable to endotoxaemia. Leukopenia, preceded by a fluctuating white cell count, was observed in horses showing clinical signs. The commercial intravenous fluid had no effect on the white cell count or on the clinical state. Precautions to be taken and recommendations are made with regard to the monitoring of horses in which one might be forced to use non-commercial intravenous fluids.
Yamada K, Inui T, Itoh M, Yanagawa M, Sato F, Tominari M, Mizobe F, Kishimoto M, Sasaki N.A Thoroughbred horse with severe chronic laminitis of both forelimbs was evaluated on the same day with magnetic resonance imaging (MRI) and computed tomography (CT). Both MRI and CT revealed loss of the dorsal aspect of the cortical bone of the 3rd phalanx and sclerosis. CT reflected the status of the horny layer and bone of the affected feet, while MRI depicted inflammation of the laminar corium, together with tendon edema. On the 3-dimensional CT venogram, vessels were visualized in both the right and left forelimbs, although there was a difference in the vasculature of the coronary plexus ...
