Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Leroy G, Callède L, Verrier E, Mériaux JC, Ricard A, Danchin-Burge C, Rognon X.The genetic diversity and structure of horses raised in France were investigated using 11 microsatellite markers and 1679 animals belonging to 34 breeds. Between-breed differences explained about ten per cent of the total genetic diversity (Fst = 0.099). Values of expected heterozygosity ranged from 0.43 to 0.79 depending on the breed. According to genetic relationships, multivariate and structure analyses, breeds could be classified into four genetic differentiated groups: warm-blooded, draught, Nordic and pony breeds. Using complementary maximisation of diversity and aggregate diversity appr...
Koch TG, Berg LC, Betts DH.Stem cells from various tissues hold great promise for their therapeutic use in horses, but so far efficacy or proof-of-principle has not been established. The basic characteristics and properties of various equine stem cells remain largely unknown, despite their increasingly widespread experimental and empirical commercial use. A better understanding of equine stem cell biology and concepts is needed in order to develop and evaluate rational clinical applications in the horse. Controlled, well-designed studies of the basic biologic characteristics and properties of these cells are needed to m...
Huthmann S, Staszyk C, Jacob HG, Rohn K, Gasse H.The Curve of Spee is well known, yet hardly understood in the horse, as there is a striking lack of biometrically related data which could help to explain its biomechanical significance. Older horses display drastic alterations of the Curve of Spee in routine clinical examinations. Since the Curve of Spee is known to be biomechanically related to the masticatory forces in humans, the same may apply to the equine, and masticatory deficits can be expected in the geriatric horse. Quantitative data of the Curve of Spee cannot be obtained directly by means of measurements in the horse's long and na...
Bade D, Portis E, Keane C, Hallberg J, Bryson L, Sweeney M, Boner P.In vitro activity of ceftiofur and six other antimicrobial agents was evaluated against 79 Streptococcus equi subsp zooepidemicus isolates collected from horses with respiratory disease in Europe during 2007 and 2008. In addition, the in vitro activity of ceftiofur and other antimicrobial drugs was assessed against 59 S. equi subsp zooepidemicus and 49 S. equi subsp equi isolates collected by veterinary diagnostic laboratories in Europe from 2002 to 2006. The lowest concentration of ceftiofur that inhibited the growth of 90% of the isolates (MIC90) was 0.12 microg/ml, with the Clinical Laborat...
Bugno-Poniewierska M, Jabłońska Z, Słota E.Fluorescence in situ hybridization (FISH) is widely used in the study of chromosome structure and organization. Cytogenetic evaluation of chromosomes using FISH technique plays an increasingly important role in diagnosing karyotype changes in both somatic and reproductive cells. The aim of the study was to optimize the conditions of stallion sperm decondensation, which have a significant effect on the results of fluorescence in situ hybridization. Appropriate type and time of decondensation was chosen for the sperm of every stallion. It was found that decondensation performed using a preparati...
Wolf TM, Gandolf AR, Dooley JL, Atkinson MW, Wolfe BA.Vaccination has been an important component of preventative health care programs of North American zoologic institutions in their protection of valuable species against West Nile virus (WNV) infection since its detection in 1999. Although approved only for horses, commercial WNV vaccine has been used for the purpose of protection of nondomestic species, including avian, equid, and rhinoceros species. Currently, there are two commercial equine vaccines available, a killed vaccine and a recombinant viral-vectored vaccine. Both products have been used for the vaccination of Greater One-horned rhi...
Rourke KM, Kohn CW, Levine AL, Rosol TJ, Toribio RE.Calcium has important physiological functions, and disorders of calcium homeostasis are frequent in horses. We have made important progress understanding equine calcium homeostasis; however, limited information on equine calcitonin (CT) is available, in part because of the lack of validated CT assays. To determine the CT response to high ionized calcium (Ca(2+)) concentrations in healthy horses, we induced hypercalcemia in 10 healthy horses using a calcium gluconate 23% solution (5mg/kg; 120 mL/500 kg horse) infused over 4 min. Four horses were infused with 120 mL of 0.9% NaCl and used as cont...
Hendriks WK, Colenbrander B, van der Weijden GC, Stout TA.Ultrasonographic examination of the equine fetus in mid-late gestation is usually performed only if there are concerns about fetal or maternal health. Even then it is difficult to determine whether development is 'normal' for gestational age because the reference values include considerable error margins. This study examined maternal factors that influence fetal growth with the aim of producing more precise late gestation fetal growth curves for Dutch Warmblood horses. Fetal development was monitored at 2-week intervals from day 100 of gestation until term in 32 mares ranging from 4 to 18 year...
Flaminio MJ, Nydam DV, Marquis H, Matychak MB, Giguère S.Susceptibility of foals to Rhodococcus equi pneumonia is exclusive to the first few months of life. The objective of this study was to investigate the immediate immunologic response of foal and adult horse antigen-presenting cells (APCs) upon infection with R. equi. We measured the activation of the antigen-presenting major histocompatibility complex (MHC) class II molecule, costimulatory molecules CD40 and CD86, the cytokine interleukin-12 (IL-12), and the transcriptional factor interferon regulatory factor 1 (IRF-1) in monocyte-derived macrophages (mMOs) and dendritic cells (mDCs) of adult h...
Müller I, Pinto E, Santibáñez MC, Celedón MO, Valenzuela PD.The equine influenza virus is the causal agent of influenza in horses. In July 2006, horses from various regions of Chile presented fever, serious nasal discharge, dry cough, anorexia and depression. Here we describe the isolation and characterization of the virus responsible for this outbreak. The virus was identified as equine influenza virus H3N8, since haemagglutination was inhibited by an anti-A/equi/1/H3N8 serum, but not by an anti-A/equi/1/H7N7 serum. The isolate was named A/equi/2/Lonquén/06 (H3N8). In addition, we describe the isolation and sequencing of the haemagglutinin, neuramini...
Reid CJ, Thompson L, Donnelly S, Deaton CM, Marlin DJ, Carrington SD, Irwin JA.Recurrent airway obstruction (RAO) is a chronic inflammatory condition in equine lung, which may share a common immunological basis with human asthma, in which dysregulated Th2 responses occur. Mammals express chitinases and chitinase-like proteins, two of which are active enzymes, chitotriosidase and acidic mammalian chitinase (AMCase). Both enzymes are upregulated in a range of inflammatory conditions, including asthma. We investigated the activity of chitinase in bronchoalveolar lavage fluid from horses with and without RAO in response to organic dust challenges. No significant differences ...
Muir P, Peterson AL, Sample SJ, Scollay MC, Markel MD, Kalscheur VL.Repetitive bone injury and development of stress fracture is a common problem in humans and animals. The Thoroughbred racehorse is a model in which adaptive failure and associated development of stress fracture is common. We performed a histologic study of the distal end of the third metacarpal bone in two groups of horses: young Thoroughbreds that were actively racing (n = 10) and a group of non-athletic horses (n = 8). The purpose of this study was to determine whether development of articular microcracks was associated with specific alterations to subchondral plate osteocytes. Morphometric ...
Andersson LS, Juras R, Ramsey DT, Eason-Butler J, Ewart S, Cothran G, Lindgren G.Equine Multiple Congenital Ocular Anomalies (MCOA) syndrome consists of a diverse set of abnormalities predominantly localized to the frontal part of the eye. The disease is in agreement with a codominant mode of inheritance in our horse material. Animals presumed to be heterozygous for the mutant allele have cysts originating from the temporal ciliary body, peripheral retina and/or iris. In contrast, animals predicted to be homozygous for the disease-causing allele possess a wide range of multiple abnormalities, including iridociliary and/or peripheral retinal cysts, iridocorneal angle abnorm...
Giuliano EA, MacDonald I, McCaw DL, Dougherty TJ, Klauss G, Ota J, Pearce JW, Johnson PJ.Local photodynamic therapy (PDT) is a novel cancer therapy in veterinary ophthalmology. A prospective pilot study seeking to demonstrate proof of principle and safety for the treatment of equine periocular squamous cell carcinoma (PSCC) was therefore conducted. We hypothesized that surgical excision with adjunctive local PDT is an effective and safe treatment for equine PSCC. Methods: Nine horses (10 eyes) with PSCC were treated with surgical resection, local infiltration of resulting wound beds with 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH) and irradiation with 665-nm wavelength ...
Smith KM, Scase TJ, Miller JL, Donaldson D, Sansom J.To investigate whether cyclooxygenase-2 (COX-2) is expressed by equine ocular and adnexal squamous cell carcinomas (SCC). Methods: Forty-three samples of histologically confirmed cases of ocular SCC or carcinoma in situ (CIS) from 34 horses presented to the Animal Health Trust between 1992 and 2004 were subjected to a standard, two-layered, indirect immunohistochemical method using a rabbit polyclonal antihuman COX-2 antibody. Ten formalin-fixed, paraffin-embedded tissue samples taken from recognized predilection sites for SCC, from the grossly normal eyes of 10 horses euthanized for reasons u...
Deeg CA.Equine recurrent uveitis (ERU) is a disease with high prevalence and relevance for the equine population, since it results in blindness. Over the last decade, important advancements have been made in our understanding of the underlying immune responses in this disease. ERU is mediated by an autoaggressive Th1 response directed against several retinal proteins. Interphotoreceptor-retinoid binding protein (IRBP) and cellular retinaldehyde-binding protein (CRALBP) are capable to induce ERU-like disease in experimental horses, with the unique possibility to activate relapses in a well-defined mann...
Cogger N, Evans DL, Hodgson DR, Reid SW, Perkins N.To describe the incidence rate of musculoskeletal (MS) injuries and investigate the factors that influence recovery from MS injury in young Thoroughbred horses in Australia. Methods: Training and injury data were collected at fortnightly intervals from 14 trainers in New South Wales. Incidence rates were calculated for initial injuries stratified by age-class and sex. Survival analysis methods were used to investigate the time to recovery after the first MS injury (measured as a start in a race or barrier trial). Results: For the 248 racehorses enrolled, there were 428 injuries recorded; 2-yea...
Schaaf KL, Kannegieter NJ, Lovell DK.Ten horses presented with severe distortion of the facial contour, crepitus on palpation and mild to moderate epistaxis. Individual horses also showed ocular damage, ptosis, severe dyspnoea and movement of the facial bones concurrent with respiration. The fracture fragments were exposed using a large curvilinear incision and elevated using a retractor, periosteal elevator, chisel or Steinmann pin. The fracture fragments were unstable following reduction and fixation was necessary. Stabilisation was achieved with polydioxanone sutures placed through holes drilled in opposing sides of the fractu...
Wilkie DA, Colitz CM.The purpose of this review is not to specifically discuss the techniques of veterinary cataract surgery, but rather to emphasize some of the differences between the veterinary and human cataract patients, procedures and outcomes. Results: In general, veterinary cataract surgery has more similarities than differences when compared to its human counterpart. This is especially true when comparing pediatric cataract patients. Veterinary cataract surgery has changed dramatically in recent years with regards to surgical technique, ocular pharmacology, viscoelastic devices, phacoemulsification, and t...
De Leo M, Giorgi M, Saccomanni G, Manera C, Braca A.Tramadol is a centrally acting analgesic drug that has been used clinically for the last two decades to treat pain in humans. The clinical response of tramadol is strictly correlated to its metabolism, because of the different analgesic activity of its metabolites. O-Desmethyltramadol (M1), its major active metabolite, is 200 times more potent at the micro-receptor than the parent drug. In recent years tramadol has been widely introduced in veterinary medicine but its use has been questioned in some species. The aim of the present study was to develop a new sensible method to detect the whole ...
Wilsher S, Allen WR.Eight day 10 horse embryos were transferred non-surgically to recipient mares that had ovulated 7 days after the donors. The embryonic vesicle was seen ultrasonographically in all eight recipients, and three out of eight (38%) of the vesicles developed an embryo proper with a beating heart. Conceptus expansion was initially slower than that in control mares but continued until day 22 (recipient day 15). Time of fixation of the vesicle was related to its diameter, rather than uterine stage. Although the embryo proper first appeared ultrasonographically on day 22, as normal, it grew more slowly ...
Miragliotta V, Lussier JG, Theoret CL.Healing of wounds located on the distal limbs of horses is often complicated by retarded epithelialization and the development of exuberant granulation tissue (proud flesh). Treatments that definitively resolve this pathological process are still unavailable. Molecular studies of the repair mechanism might contribute to the development of new therapeutic strategies. The study presented herein aimed to clone the full length cDNA and to study the spatio-temporal expression profile of mRNA and protein for LAMR1, previously attributed a role in wound epithelialization, during the repair of body an...
Tharasanit T, Colleoni S, Galli C, Colenbrander B, Stout TA.Vitrifying oocytes is a potentially valuable means of preserving the female germ line, but significantly compromises oocyte developmental competence. This study examined the hypothesis that the cumulus complex protects the oocyte during vitrification. Vitrified-warmed immature cumulus oocyte complexes (COCs) were labelled with a plasma membrane impermeant DNA marker (ethidium homodimer-1) to examine the percentage and location of dead cumulus cells, and to investigate the effect of the proportion of dead cells (+1,+2 or +3) on the success of in vitro maturation (IVM). Further, oocytes were lab...
Morita H, Shiratori C, Murakami M, Takami H, Toh H, Kato Y, Nakajima F, Takagi M, Akita H, Masaoka T, Hattori M.Four bacterial strains, designated ST18(T), HM244, HM250 and DI49, were isolated from the fresh faeces of four thoroughbred horses in Japan. Cells were Gram-positive, strictly anaerobic, catalase-negative, non-spore-forming, non-motile rods that occurred in chains. They were placed in the same subcluster based on 16S rRNA gene sequence analysis, phenotypic characteristics and levels of DNA-DNA relatedness. Their DNA G+C content ranged from 36 to 38 mol%. Lactobacillus catenaformis, Lactobacillus vitulinus and Catenibacterium mitsuokai belong to cluster XVII of the Clostridium subphylum. Strain...
Journal of medical entomologyDecember 9, 2008
Volume 45, Issue 6 1152-1155 doi: 10.1603/0022-2585(2008)45[1152:tobcbd]2.0.co;2
Schwint ON, Knowles DP, Ueti MW, Kappmeyer LS, Scoles GA.The tropical horse tick, Dermacentor nitens, is a natural vector of Babesia caballi in the Americas. B. caballi, one of the etiologic agents of equine piroplasmosis, occurs widely throughout the world, but the United States and a few other countries are considered to be free of infection. B. caballi is transovarially transmitted by the one-host tick D. nitens; we tested the hypothesis that B. caballi can persist in multiple generations of D. nitens in the absence of opportunity to reacquire infection from a susceptible equine host. Partially engorged female D. nitens were collected from a B. c...
Burn JF, Brockington C.Deformation of the hoof capsule occurs during stance phase as a result of loading by the distal phalanx. The objective of this study was to evaluate optical motion capture as a technique for measuring hoof deformation during locomotion, and to quantify the deformation of the dorsal wall during stance phase. The front left feet of 3 clinically sound horses were used for this study. The hoof wall was cleaned and 9 retroreflective markers were glued to the lateral and dorsal hoof wall, and shoe. Each horse was trotted in a straight line at constant speed while marker positions during stance phase...
Shi L, Wang D, Riggs CM, Qin L, Griffith JF.Voxel-based morphometry (VBM) is a computational technique that has been used to analyze statistical differences between groups of MR brain images. This study outlines a new VBM pipeline, designed for determining statistical variation in bone mineral density (BMD). CT images of proximal sesamoid bone (PSB) specimens from the right forelimb of six racehorses that had suffered PSB fractures were compared with six age-matched control specimens. Following segmentation, masked gray-scale images were co-aligned to a statistical template generated with all 12 CT datasets iteratively. Student t-tests ...
D' Fonseca NMM, Beukers M, Wijnberg ID, Navas de Solis C, de Ruijter-Villani M, van Doorn DA, Stout TAE, Roelfsema E.Changes in cardiovascular parameters, including blood pressure (BP) and cardiac anatomical dimensions, are an inconsistent feature of the equine metabolic syndrome. The order in which these changes arise is unknown. Objective: Determine the order in which EMS-associated changes in cardiovascular parameters arise. Methods: Twenty Shetland pony mares. Methods: High-energy (HE) diet mares were fed 200% of net energy requirements for 1 (n = 3) or 2 (n = 7) consecutive diet-years, with 17 weeks of hay-only between years. Noninvasive BP measurements and echocardiograms were performed during bo...
Herrera-Luna CV, Budik S, Helmreich M, Walter I, Aurich C.Glucocorticoids (GCs) as mediators of the stress response may affect Leydig cell function by inhibiting either luteinizing hormone receptor expression or testosterone biosynthesis. The isozymes 11β-hydroxysteroid dehydrogenase (11βHSD) 1 and 11βHSD2 control the intracellular cortisol levels. Little is known about the effects of stress on fertility in the equine. The objective of the present study was to determine the presence and cellular localization of glucocorticoid receptors (GCR) and glucocorticoid-metabolizing enzymes (11βHSD1 and 11βHSD2) in equine epididymal and testicular tissue ...
El-Assaad I, Di Bari JA, Yasuda K, Divers TJ, Summers BA, de Lahunta A, Mohammed H.Equine motor neuron disease (EMND) is a neurodegenerative disorder of unknown etiology affecting horses worldwide. Trans-Active Response DNA Binding Protein of 43 kDa (TDP-43) has been reported in the central nervous system (CNS) of several neurodegenerative conditions in humans including Amyotrophic Lateral Sclerosis (ALS) and assumed to play role in the disease. We examined whether horses afflicted with EMND express the TDP-43 in CNS. Ten horses with EMND and 6 controls of different ages and breed we enrolled. Detection of presence of TDP-43 protein in the CNS was analyzed by immunohistoche...
Rossano MG, Kaneene JB, Marteniuk JV, Banks BD, Schott HC, Mansfield LS.A cross-sectional study of serum antibodies to Sarcocystis neurona (the etiologic agent of equine protozoal myeloencephalitis, EPM) was performed on Michigan equids. Our objectives were to determine the seroprevalence of antibodies to S. neurona in Michigan equids and to identify specific risk factors for seropositivity. A random, weighted sample of Michigan horse farms (stratified by the state's opossum (Didelphis virginiana) population and the number of equids on each operation) was selected. Ninety-eight equine-operation owners agreed to participate, and blood collection occurred from late ...
Morresey PR, White GW, Poole HM, Hu T, Yin M, Sundman EA.OBJECTIVE To evaluate the effectiveness and safety of dipyrone to control pyrexia in horses with naturally occurring disease under field conditions. ANIMALS 138 horses with pyrexia and various infections evaluated at 14 veterinary sites in 12 states. PROCEDURES In the first (effectiveness) phase of this 2-phase study, horses were randomly assigned 3:1 to receive 1 dose of dipyrone (30 mg/kg [13.6 mg/lb], IV) or an equivalent amount of placebo. Effectiveness was defined as a decrease in rectal temperature ≥ 1.1°C (2°F), compared with the pretreatment value, or a rectal temperature of ≤ 38...
Davis JL, Salmon JH, Papich MG.The purpose of this study was to determine the pharmacokinetics and tissue fluid distribution of cephalexin in the adult horse following oral and i.v. administration. Cephalexin hydrate (10 mg/kg) was administered to horses i.v. and plasma samples were collected. Following a washout period, cephalexin (30 mg/kg) was administered intragastrically. Plasma, interstitial fluid (ISF) aqueous humor, and urine samples were collected. All samples were analyzed by high-pressure liquid chromatography (HPLC). Following i.v. administration, cephalexin had a plasma half-life (t(1/2)) of 2.02 h and volume o...
The Journal of heredityJuly 1, 1990
Volume 81, Issue 4 250-256 doi: 10.1093/oxfordjournals.jhered.a110987
Woolf CM.The results of a previous study were compatible with the hypothesis that common white facial markings in the Arabian horse have a multifactorial mode of inheritance. I expanded that study to (1) include the legs and therefore obtain insight into the heritability of common white markings in all peripheral regions (face and legs) of the Arabian horse and (2) investigate the influence of sex and the genotypes that produce the bay and chestnut phenotypes on the variation in common white markings. Both studies were based on computerized data obtained from the Arabian Horse Registry of America, Inc....
Slocombe RF, Huntington PJ, Friend SC, Jeffcott LB, Luff AR, Finkelstein DK.Nine horses with clinical signs of Australian Stringhalt were killed and tissues collected for a detailed pathological study. Lesions were limited to peripheral nerves and muscles. The most severely affected nerves were the superficial and deep peroneal, distal tibial, plantar digital, volar and recurrent laryngeal nerve with changes characterised by a selective loss of large diameter myelinated fibres with various degrees of demyelination, fibrosis, Schwann cell proliferation and onion-bulb formation. A routine evaluation of the brain and spinal cord by light microscopy failed to reveal any c...
Stout TA, Lamming GE, Allen WR.In a recent study, continuous administration of oxytocin by subcutaneous minipump to mares from day 8 to 20 after ovulation prevented luteolysis in most of the treated but none of the control mares, indicating a role for oxytocin in cyclical luteolysis in mares. In the present study, measurement of oxytocin concentrations in uterine flushings recovered from nine mares during days 14-18 after ovulation gave values that were many times higher than those measured concurrently in peripheral plasma. Furthermore, intrauterine administration of oxytocin to four mares on day 14 after ovulation stimula...
Roberts K, Hemmings AJ, McBride SD, Parker MO.Large animal models of human neurological disorders are advantageous compared to rodent models due to their neuroanatomical complexity, longevity and their ability to be maintained in naturalised environments. Some large animal models spontaneously develop behaviours that closely resemble the symptoms of neural and psychiatric disorders. The horse is an example of this; the domestic form of this species consistently develops spontaneous stereotypic behaviours akin to the compulsive and impulsive behaviours observed in human neurological disorders such as Tourette's syndrome. The ability to non...
Lind EO, Uggla A, Waller P, Höglund J.The aim of this study was to investigate the suitability of a larval development assay (LDA) for the determination of anthelmintic resistance in cyathostomin nematode populations of the horse. In addition, comparison of results between geographic regions, types of horse establishment, and the use of anthelmintics in Sweden, was established. Seventy horse herds from different parts of Sweden were sampled, and strongyle eggs from the faeces of 54 of those were investigated by an LDA (DrenchRite). The following anthelmintics were tested: thiabendazole (TBZ), levamisole (LEV), ivermectin monosacch...
Maxwell MH.A series of experiments is described in which attempts were made to produce an avian eosinophilia using various agents. Although none of the experiments was decisive, two demonstrated a slight rise in the eosinophil counts. In one experiment horse serum was injected into a group of fowls on alternate days for 42 days. No eosinophils were seen in any blood smears after this treatment. After a rest period of eight days the birds received further injections for 10 days. The mean eosinophil count rose to over 4 per cent with a range of 1 to 11 per cent. It is considered that this type of response ...
Smith S, Dyson SJ, Murray RC.Distal sesamoidean ligament injury is a recognized cause of lameness but diagnosis using ultrasonography is sometimes difficult. Herein, we describe the normal appearance of the distal sesamoidean ligaments on magnetic resonance (MR) images and the changes that occur when the ligaments are injured. The appearance of the distal sesamoidean ligaments on MR images from 66 control horses and 58 horses with distal sesamoidean desmitis were described and the cross-sectional area and signal intensity of the ligaments measured. In control horses, the ligaments had a characteristic appearance and stron...
Sojka JE, Weiss JS, Samuels ML, You GM.The effect of the somatostatin analogue, octreotide, on gastric fluid pH was investigated in 4 ponies. Gastric fluid pH was determined after SC administration of octreotide or physiologic saline solution (control). A baseline sample of fluid was obtained, the agent was given, and 8 additional samples were collected hourly. Administration of octreotide at all dosages tested (0.1, 0.5, 1.0, and 5.0 micrograms/kg of body weight) increased gastric pH to > 5.0. Baseline values were consistently 4.0 for 2.4 +/- 1.2, 4.8 +/- 0.8, 5.7 +/- 1.3, and 5.4 +/- 2.6 (mean +/- SD) continuous hours, respec...
Bollwein H, Kolberg B, Stolla R.In recent years, a positive relationship between genital perfusion and fertility has been established; in species other than horses, uterine and ovarian perfusion was improved by exogenous estrogen but impaired by exogenous progestin. The goal of the present study was to investigate the effect of exogenous estrogen and progestin on uterine and ovarian blood flow in cycling mares. Five Trotter mares were examined daily during three estrous cycles. Mares were given no treatment, altrenogest (0.044 mg/kg BW) orally from Day 0 (ovulation) to Day 14 and estradiol benzoate (5mg i.m.) on Days 0, 5, a...
Hosaka YZ, Takahashi H, Uratsuji T, Tangkawattana P, Ueda H, Takehana K.The aim of this study was to determine the characteristic differences in tendinocytes derived from tendons in the equine forelimb, superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT) and common digital extensor tendon (CDET), in morphology, proliferation, collagen production ability and ability for synthesis of matrix metalloproteinases (MMPs). Significant differences were observed in cell number in vivo. The cellular number was largest in the SDFT and smallest in the CDET. The values of in vitro proliferation ratios and ability for synthesis of collagen and MMPs were l...
Fong CK, Hsiung GD.Development of equine herpesvirus strain 82A was studied in cells from primary horse kidney (HOK) cultures and an equine dermis (ED) cell strain. HOK and ED cells are equally susceptible to the 82A virus infection and yield about the same amount of infectious virus. Intranuclear inclusions were present in both cell systems, but a ring-shaped syncytial formation was observed only in infected ED cells. Ultrastructural studies revealed the presence of dense granules 30 nm in diameter and characteristic star-like clusters of granules in the infected HOK cells, but these granules were rarely seen i...
Hensel M, Meason-Smith C, Plumlee QD, Myers AN, Coleman MC, Lawhon S, Rodrigues Hoffmann A, Rech RR.Pulmonary mycosis secondary to enterocolitis is an uncommon diagnosis in equine medicine, but is thought to result from mucosal compromise and translocation of enteric fungi. The aetiological agent associated with translocation is often identified based on fungal culture or hyphal features in histological sections. In order to understand better the aetiological agents involved, six horses diagnosed with Salmonella enteritis and concurrent pulmonary mycosis were identified retrospectively through a database search of veterinary teaching hospital records. Samples from these cases were subjected ...
de Laat MA, van Haeften JJ, Sillence MN.Managing equine hyperinsulinemia is crucial for preventing laminitis, but our understanding of the mechanisms involved in insulin dysregulation in this species is incomplete. C-peptide is co-secreted with insulin but is resistant to hepatic metabolism and can be used to study insulin dysregulation. This study examined C-peptide secretion in serial blood samples collected after oral and i.v. dextrose (0.75 g/kg) administration to 9 ponies (BCS, 7.1 ± 0.5). The ponies were designated as hyperinsulinemic (HI) or normoinsulinemic (NI) responders before the study, using oral glucose tests and fast...
Else RW, Holmes JR.The normal histology of cardiac tissues has been described by many authors, for example Gross and Kugel (1931), Trautmann and Fiebiger (1952), Gould (1968), Bloom and Fawcett (1969) and Ham (1969). In the horse, a few reports have described microscopic valvular pathology in detail (Ackerknecht 1923, Imre 1933, Ubach and Cler 1944). Experimentally induced lesions have been reported by Wadsworth (1919), Wadsworth and Sickles (1927) and Miller (1944), and endocarditis was described by Winqvist (1945) and Dobin (1959, 1968).
In 1966, Smetzer, Bishop and Smith outlined the valvular pathology ass...
Maitan P, Bromfield EG, Stout TAE, Gadella BM, Leemans B.Conventional in vitro fertilization is not efficacious when working with equine gametes. Although stallion spermatozoa bind to the zona pellucida in vitro, these gametes fail to initiate the acrosome reaction in the vicinity of the oocyte and cannot, therefore, penetrate into the perivitelline space. Failure of sperm penetration most likely relates to the absence of optimized in vitro fertilization media containing molecules essential to support stallion sperm capacitation. In vivo, the female reproductive tract, especially the oviductal lumen, provides an environmental milieu that appropriate...
Warnken T, Brehm R, Feige K, Huber K.The aim of the study was to analyze key proteins of the equine insulin signaling cascade and their extent of phosphorylation in biopsies from muscle tissue (MT), liver tissue (LT), and nuchal AT, subcutaneous AT, and retroperitoneal adipose tissues. This was investigated under unstimulated (B1) and intravenously insulin stimulated (B2) conditions, which were achieved by injection of insulin (0.1 IU/kg bodyweight) and glucose (150 mg/kg bodyweight). Twelve warmblood horses aged 15 ± 6.8 yr (yr), weighing 559 ± 79 kg, and with a mean body condition score of 4.7 ± 1.5 were included in the s...
Fan Y, Lou J, Tam CC, Wen W, Conrad F, Leal da Silva Alves P, Cheng LW, Garcia-Rodriguez C, Farr-Jones S, Marks JD.Equine-derived antitoxin (BAT) is the only treatment for botulism from botulinum neurotoxin serotype G (BoNT/G). BAT is a foreign protein with potentially severe adverse effects and is not renewable. To develop a safe, more potent, and renewable antitoxin, humanized monoclonal antibodies (mAbs) were generated. Yeast displayed single chain Fv (scFv) libraries were prepared from mice immunized with BoNT/G and BoNT/G domains and screened with BoNT/G using fluorescence-activated cell sorting (FACS). Fourteen scFv-binding BoNT/G were isolated with K values ranging from 3.86 nM to 103 nM (median K 2...
Madill S, Troedsson MH, Alexander SL, Shand N, Santschi EM, Irvine CH.The aim of this study was to investigate the effect of different breeding stimuli on uterine contractility and pituitary oxytocin release in five oestrous mares, in order to design better treatments for mares with defective physical uterine clearance mechanisms. Electrodes and strain gauges were implanted surgically on the uterine myometrium and myometrial activity was monitored with a Grass polygraph. A catheter was placed non-surgically in the intercavernous sinus of each oestrous mare to sample pituitary venous blood and a second catheter was placed in the jugular vein. Continuous sampling ...
Bescoby SR, Davis SA, Sherriff M, Ireland AJ.Routine equine odontoplasty is performed by both Veterinary Surgeons and Equine Dental Technicians. The production of aerosolised particulates from motorised equipment has been well documented in human orthodontics but has yet to be investigated in the veterinary industry. Objective: To assess the size, quantity and composition of particulates produced during routine motorised odontoplasty and to model their deposition in the human respiratory tree. Methods: Analytic observational study. Methods: Fifteen-minute routine motorised odontoplasties were performed on cadaver heads with monitoring eq...
Whitton RC, Jackson MA, Campbell AJ, Anderson GA, Parkin TD, Morton JM, Boden LA.A retrospective cohort study was performed to compare the rates of musculoskeletal injury (MSI) in horses receiving local corticosteroid injection (LCI) with those that were untreated and those prior to treatment. Of the 1911 study horses, 392 had been treated. A LCI was defined as any injection of corticosteroid into or adjacent to a synovial structure, muscle, or tendon/ligament. A MSI was defined as any limb injury identified by a veterinarian, following which the horse did not race for at least 6 months, or was retired. Hazard ratios (HR) comparing hazard of injury following injection to t...
Ohnesorge B, Deegen E, Miesner K, Geldermann H.Laryngoscopic examination during sedation was performed on 24 stallions and on their offspring (240 foals and 474 adult horses). Additionally the dams (n = 308) of 35 foals and 216 horses were examined. With the bilateral comparison of the arytaenoid movements the function of the abductory and adductory laryngeal muscles were evaluated and the left abductory dysfunction (idiopathic laryngeal hemiplegia, ILH) was divided into six degrees. The incidence and degree of ILH depended on age and the occurrence of the same dysfunction in the parents. Foals suffered in significantly lower number (24.7 ...
Zink MC, Johnson JA, Prescot JF, Pascoe PJ.The in-vitro interaction of Corynebacterium equi and foal alveolar macrophages was examined qualitatively and quantitatively using cells collected by sequential bronchoalveolar lavage at 2-week intervals from birth until 14 weeks of age. Total and differential counts were performed on the recovered cells. Macrophages were identified using the non-specific esterase strain. Cultures of the alveolar macrophages were challenged with C. equi suspensions and the process and extent of ingestion was examined by light and electron microscopy. Few macrophages were recovered from the lungs of foals less ...
