Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
Artursson K, Gunnarsson A, Wikström UB, Engvall EO.For diagnosis of equine granulocytic ehrlichiosis (EGE) serological testing of antibodies to Ehrlichia equi is frequently used. An elevated antibody level is often misinterpreted as confirmative of active infection and results in treatment with antibiotics. If only seropositivity is considered as the diagnostic criterium, many horses showing convalescence titres will be treated. This study was undertaken to obtain information about the kinetics of antibodies during the course of infection and, for this purpose, 45 horses with clinical signs of EGE and confirmed ehrlichiaemia were monitored ser...
Pardoe CH, Wilson AM.Hoof wall cracks need mechanical stabilisation to allow healing. Common techniques are fixation with screws, wires and plates or bonding of a patch across the crack. An in vitro system to determine the shear properties of equine hoof crack repairs is described. The force and displacement at yield, stiffness and ultimate force were determined for 4 repair techniques based on an acrylic material, polyurethane patch attached with cyanoacrylate adhesive, steel plate attached with screws and a transverse metal bar cut into the hoof wall. The cyanoacrylate bonded patch repair had lower values for al...
Yeruham I, Avidar Y, Perl S.Primary photosensitization was observed in 3 Appaloosa mares. The skin lesions were diffuse erythema followed by edema and subsequently weeping and finally dry gangrene and ulceration. The severe photosensitivity dermatitis was apparently induced by gluten ingestion. Resolution of lesions occurred after withdrawal of the suspected dairy concentrate feed and prevention of exposure to sunlight. Neither the ponies nor donkey, which were not fed with the suspected concentrate, exhibited similar skin lesions or other clinical abnormalities. Gluten metabolites may contain photodynamic agents that ca...
Bezerra PS, Driemeier D, Loretti AP, Riet-Correa F, Kamphues J, de Barros CS.Three outbreaks of monensin poisoning caused 12 deaths in 16 horses. The illnesses were associated with the ingestion of the same batch of a commercial ration labeled for feeder calves which contained 180 +/- 20 ppm sodium monensin. The morbidity rate was 100% and lethality was 60%, 75%, and 100%. Clinical signs were tachycardia and cardiac arrythmia, groaning, incoordination, sudoresis, recumbency, and paddling movements with the limbs before death. Two horses had dark discolored urine (myoglobinuria). Serum levels of creatine phosphokinase activity were increased. Main necropsy findings were...
Dowling PM.The well-developed defense barriers of the CNS and the expense of drug therapy limit the pharmacologic options for the treatment of neurologic diseases in horses. New approaches to controlling inflammation in the CNS are improving the outcomes of bacterial meningitis. The appropriate treatment of EPM remains controversial. More research is needed to evaluate the pharmacokinetics and pharmacodynamics of drugs in the CNS of the horse. Behavioral pharmacology has become fashionable in human and small animal medicine, but it needs to be evaluated for the potential of unethical use in performance h...
Wichtel ME, Buys E, DeLuca J, Stringel G.This article focuses on the pharmacologic properties of drugs commonly used in the treatment of neonatal septicemia and its complications. Rational therapy demands an awareness of not only the pharmacology of individual drugs but also the interactions and anticipated fate of such drugs in the rapidly changing physiologic environment of the neonate. Further research in the area of equine neonatal pharmacology should greatly assist our understanding of the impact of the disease state on the unique physiology of the newborn and should allow us to better predict the ultimate fate of drugs commonly...
Whittem T.This article presents in easily accessible form a collection of drug names and dose rates for the drugs recommended or referred to by the authors of the individual articles in this issue. Although the formulary provides recommendations for drug use, the reader is cautioned that the responsibility for the choice of agent, formulation, dose, and dose interval lies with the clinician. The author also addresses regulations that govern the use of drugs in competition horses.
Marti E, Urwyler A, Neuenschwander M, Eicher R, Meier D, de Weck AL, Gerber H, Lazary S, Dahinden CA.Sulfidoleukotrienes (sLT) generated in vitro after incubation of equine peripheral blood leukocytes (PBL) with different inducing agents were determined in 18 healthy and 16 insect bite dermal hypersensitivity (IDH)-affected horses. PBL from these 32 horses were stimulated with Concanavalin A, Parascaris equorum, Culicoides nubeculosus and Simulium extracts, and with a six-Grass mix. The cells of all but four horses generated sLT after incubation with Concanavalin A; these four horses did also not produce sLT with the other inducing agents. Of the 28 remaining horses (12 affected with IDH and ...
al-Ani FK.Epizootic lymphangitis is a relatively common infectious disease of horses and other liquids in certain parts of the world. The infection rate varies according to the geographic area and the age of the animal. The disease is most commonly characterised by a cord-like appearance of the subcutaneous lymphatic and cutaneous pyogranulomas, the discharge from which contains spherical or pear-shaped bodies of the causal agent, Histoplasma farciminosum. Diagnosis can be made by the demonstration of typical organisms in stained smears, culture and tissue sections. Serological tests and a skin hypersen...
Li F, Leroux C, Craigo JK, Cook SJ, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) is genetically one of the simplest lentiviruses in that the viral genome encodes only three accessory genes, tat, rev, and S2. Although serological analyses demonstrate the expression of the S2 protein in persistently infected horses, the role of this viral gene remains undefined. We recently reported that the S2 gene is not essential for EIAV replication in primary equine macrophages, as EIAV mutants lacking the S2 gene replicate to levels similar to those of the parental virus (F. Li, B. A. Puffer, and R. C. Montelaro, J. Virol. 72:8344-8348, 1998). We n...
Foreman JH.Differentiation of diseases of the equine respiratory tract is based on history, clinical signs, auscultation, endoscopy, imaging, and sampling of airway exudate. Upper respiratory therapies include surgical correction of airway obstructions; flushing of localized abscesses (strangles), guttural pouch disease, or sinusitis; and oral or parenteral antibiotic and anti-inflammatory therapy if deemed necessary. Pneumonia usually is treated with antimicrobials, anti-inflammatories, and bronchodilators. Pleural drainage is indicated if significant pleural effusion is present. The most commonly used ...
Idrissi Bougrine S, Fassi Fihri O, el Harrak M, Fassi Fehri MM.A vaccination protocol involving three horses, with five repeated injections of inactivated serotype 4 African horse sickness virus, was undertaken to determine a possible threshold for the appearance of antibodies against the non-structural protein NS3. Using an indirect enzyme-linked immunosorbent assay, with the recombinant NS3 protein as an antigen, the authors detected a response to NS3 as of the second injection for the first horse and after four injections for the second horse. No response to NS3 was detected for the third horse. The results show that the inactivated vaccine is insuffic...
Jose-Cunilleras E, Hinchcliff KW.Pharmacologic treatment of diseases of the urinary tract of horses is limited to administration of antibiotics for treatment of urinary tract infections (UTIs), administration of drugs that alter urine pH, administration of drugs that alter bladder smooth muscle function or urethral sphincter tone, and treatment of acute renal failure. The indications, mechanisms of action, pharmacokinetic characteristics, and adverse effects of these agents in each of these groups are discussed in this article. The use of the agents is discussed within the context of the pathophysiology of the disease being t...
Hamor RE, Whelan NC.Corneal ulcers are one of the most common ocular disease presentations in the horse. With the use of correct diagnostic techniques and selection of an appropriate treatment regimen, most cases result in a satisfactory outcome. The eye does not respond well to inflammation, and in complicated ulcers, this should be managed aggressively using systemic NSAIDs with a high priority assigned to removing the infectious agent. Care needs to be taken to avoid topical or systemic corticosteroid use for the treatment of equine ocular disease, however, unless the clinician is completely sure that the corn...
van Hoogmoed L, Yarbrough TB, Lecouteur RA, Hornof WJ.A 6 week old American Paint filly was admitted for evaluation of a dorsal thoracic mass suspected to be a meningocele. The diagnosis was confirmed by plain and contrast enhanced computed tomography. Surgical repair was performed by dissection of the base of the meningocele followed by ligation. No postoperative complications occurred. Contrast enhanced computed tomography was useful to confirm the diagnosis of meningocele and rule out a meningomyelocele.
Guérin G, Bailey E, Bernoco D, Anderson I, Antczak DF, Bell K, Binns MM, Bowling AT, Brandon R, Cholewinski G, Cothran EG, Ellegren H, Förster M....The goal of the First International Equine Gene Mapping Workshop, held in 1995, was the construction of a low density, male linkage map for the horse. For this purpose, the International Horse Reference Family Panel (IHRFP) was established, consisting of 12 paternal half-sib families with 448 half-sib offspring provided by 10 laboratories. Blood samples were collected and DNA extracted in each laboratory and sent to the Lexington laboratory (KY, USA) for dispatch in aliquots to 14 typing laboratories. In total, 161 markers (144 microsatellites, seven blood groups and 10 proteins) were tested f...
Fortier LA, Nixon AJ, Ducharme NG, Mohammed HO, Yeager A.To determine the outcome of horses with "complex" digital tenosynovitis treated by tenoscopic proximal annular ligament desmotomy and resection of synovial masses or adhesions, or both, within the digital sheath. Methods: Retrospective evaluation. Methods: Twenty-five horses with a clinical and ultrasonographic diagnosis of palmar or plantar proximal annular ligament constriction and ultrasonographic evidence of synovial masses or adhesions within the digital tendon sheath. Methods: Each horse had tenoscopic surgery for annular ligament desmotomy combined with adhesiolysis and/or synovial mass...
Dodam JR, Branson KR, Gross ME, Petroski GF.The purpose of this study was to assess carbon monoxide (CO) exposure during equine anesthesia with either halothane (H) or isoflurane (I) delivered in a circle rebreathing system. Methods: Prospective clinical investigation. Methods: Fifty client-owned horses. Methods: Horses were randomly assigned for anesthetic maintenance with H (n = 26) or I (n = 24). Two large animal anesthetic machines were used and assigned to a single agent for 2-4 weeks at a time. Machines were disassembled and soda lime changed prior to switching anesthetic agents. Inhalant anesthetic concentration and CO concentrat...
Shipstone , Mueller , Bettenay , Mason , Friend .The macroscopic and microscopic effects following the intradermal injection of the mast cell degranulator compound 48/80 were investigated in horses. It was found that a 1000 μg mL-1 solution of compound 48/80 could be used as an alternative to histamine as a positive control in equine intradermal allergy tests. An inflammatory cell infiltration was noted on histological examination, following compound 48/80 injection. This inflammatory cell pattern was similar to that noted for Type-I hypersensitivity.
Portas M, Boinas FS, Oliveira E Sousa J, Rawlings P.African horse sickness (AHS) was diagnosed for the first time in southern Portugal in autumn 1989, following outbreaks in Spain. AHS virus presence was confirmed by virus isolation and serotyping. An eradication campaign with four sanitary zones was set up by Central Veterinary Services in close collaboration with private organizations. Vaccination began on 6 October. In February 1990, vaccination was extended to all Portuguese equines (170000 animals). There were 137 outbreaks on 104 farms: 206 of the equidae present died (16%) or were slaughtered (14%); 81.5% were horses, 10.7% were donkeys ...
Murphy AJ, Mansfield LS.Sarcocystis neurona is a protozoan parasite that causes a neurological disease in horses called equine protozoal myeloencephalitis. The route of transmission is speculated to be by fecal-oral transfer of sporocysts shed from opossums. Controversy exists regarding both the natural life cycle for this parasite as well as the species identity of opossum Sarcocystis. To provide stage-specific material for species comparison, 27 opossums from southern Michigan were screened for Sarcocystis spp. sporocysts. Seven opossums were positive for Sarcocystis sporocysts by fecal flotation. A simplified, eff...
Davis CR, Barr BC, Pascoe JR, Olander HJ, Dubey JP.Hepatic sarcocystosis was diagnosed in a horse in association with refractory bacterial osteomyelitis and plasma cell tumor of the maxilla and hepatic salmonellosis. Gross lesions included pleural, pericardial, and peritoneal effusions, hepatomegaly, gastric ulceration, colonic edema, and proliferative tissues filling 2 maxillary dental alveoli. Histologically, liver was characterized by severe suppurative, necrotizing, periportal hepatitis, and severe periacinar necrosis. Hepatocytes frequently contained protozoal schizonts in various stages of development. In mature schizonts, merozoites wer...
Newton JR, Verheyen K, Wood JL, Yates PJ, Mumford JA.In 1998, equine influenza was diagnosed by serology and nucleoprotein enzyme-linked immunosorbent assay as the cause of acute respiratory disease in vaccinated and unvaccinated horses in the UK. The signs were generally milder in vaccinated horses and completely susceptible animals showed the most severe signs, including pyrexia, inappetence, coughing, mucopurulent nasal discharge and secondary bacterial pneumonia. In a detailed investigation of an outbreak among 52 vaccinated thoroughbreds in a flat racing yard, more than 60 per cent of the horses seroconverted on the evidence of paired serum...
Newton JR, Wood JL, Castillo-Olivares FJ, Mumford JA.Serological analysis of blood samples submitted to the Animal Health Trust showed that during 1995, 185 of 9203 unvaccinated horses (2.0 per cent) tested positive for antibodies to equine arteritis virus (EAV), and that during 1996, 46 of 8851 unvaccinated horses (0.52 per cent) tested positive. During both years thoroughbreds were the predominant breed tested and only a small proportion of these (<0.3 per cent), consisting predominantly of imported mares, were seropositive. In contrast, among standardbred horses, from which samples were actively solicited in 1995, 84 of 454 (18.5 per cent) we...
Harvey-Micay J.An 8-year-old, Thoroughbred-cross mare presented with recurrent colic. Exploratory laparotomy revealed a large mass near the right dorsal colon; white, raised foci on the liver; and enlarged mesenteric lymph nodes. Cytological examination of biopsies revealed neoplastic cells. The diagnosis of adenocarcinoma was confirmed by histological examination.
Herteman N, Bullone M, Lavoie JP.Heaves is a severe debilitating condition of horses, characterized by lower airway inflammation and permanent structural changes of the bronchial wall. Chronic inflammation promotes the formation of new vessels, a phenomenon known as angiogenesis. Narrow band imaging (NBI) endoscopy is a noninvasive technique that enhances the visualization of submucosal vessels, and commonly is employed for the study of angiogenesis in human patients. Objective: Using NBI, we aimed to determine whether or not the central airways of horses with heaves undergo angiogenesis. Methods: Horses with heaves during ex...
Fonseca AO, Botton Sde A, Nogueira CE, Corrêa BF, Silveira Jde S, de Azevedo MI, Maroneze BP, Santurio JM, Pereira DI.Pythium insidiosum is an important pathogen of mammals' species, including humans. Equine is the main species affected by this oomycete. P. insidiosum requires an aquatic environment to develop its life cycle, and the susceptible hosts are contaminated when they contact the microorganism in swampy areas. The equine pythiosis is characterized by the formation of irregular masses within the cutaneous lesions, called kunkers, which easily detach from the lesion. From these structures, it is possible to isolate P. insidiosum in pure cultures. The present study aimed to reproduce in vitro the life ...
Lauper M, Gerber V, Ramseyer A, Burger D, Lüth A, Koch C, Dolf G.There is a lack of evidence regarding genetic parameters of health traits in Swiss Warmblood horses. Objective: To estimate heritabilities of equine sarcoid disease, horn quality of hooves, prognathism and increased filling of talocrural joints as a possible indicator for osteochondrosis in Swiss Warmblood horses examined at the field tests for 3-year-olds between 2005 and 2013. Methods: Retrospective analysis of breed society database. Methods: Swiss Warmblood horses were examined clinically by 13 veterinarians at field tests in Switzerland between 2005 and 2013. The presence of sarcoids, hor...
Dixon PM, Puidupin C, Borkent D, Liuti T, Reardon RJM. Computed tomographic (CT) imaging has shown some horses with sinonasal diseases to have changes in their sinus bony structures. Scintigraphic and clinical evidence of sinus osteitis have also been reported. However, no study has objectively examined for the presence and degree of osteitis in equine sinonasal disease. To assess for the presence and extent of osteitis of sinus-related bony structures by examination of CT images of horses with clinically and sinoscopically confirmed unilateral sinonasal disease. Retrospective examination of CT images of horses with confirmed, mainly chronic (&...
Hughes JP.Contagious Equine Metritis (CEM) is a highly contagious venereal disease of horses caused by a fastidious, Gram-negative coccobacillus which grows best on chocolate agar under microaerophilic conditions (5-10% CO2). Clinically, the disease is characterized by a copious watery-to-mucopurulent, vaginal discharge two to ten days after breeding by an infected stallion (11, 13). Shortened estrous cycle lengths are common and may be the only indication of endometritis in some instances (7). Inapparent carriers of the disease in both the mare and stallion make control of the disease more difficult. O...
Martinez CR, Santangelo KS, Olver CS.Whole transferrin receptor (TfR) is present in reticulocyte exosomes. Soluble transferrin receptor (sTfR) is cleaved from whole TfR in human plasma, with the remnant cytoplasmic domain (cTfR) remaining membrane associated. In humans, sTfR is a biomarker that can detect iron deficiency in the presence of inflammatory disease. This condition is still a diagnostic dilemma in veterinary species. We aimed to (1) confirm the presence of exosomes and exosome-associated TfR in the serum of dogs, cats, and horses; and (2) to assess and compare the proportion of cTfR to total (cTfR + whole) in exoso...
Newkirk KM, Ehrensing G, Odoi A, Boston RC, Frank N.OBJECTIVE To assess insulin, glucagon, and somatostatin expression within pancreatic islets of horses with and without insulin resistance. ANIMALS 10 insulin-resistant horses and 13 insulin-sensitive horses. PROCEDURES For each horse, food was withheld for at least 10 hours before a blood sample was collected for determination of serum insulin concentration. Horses with a serum insulin concentration 20 μU/mL underwent a frequently sampled IV glucose tolerance test to determine sensitivity to insulin by minimal model analysis. Horses with a sensitivity to insulin < 1.0 × 10 L•min•mU w...
Harada K, Kanemitsu S, Akioka K, Fujita K, Nishi Y, Taura Y, Sasaki N.Fifty-four slaughtered horses were classified into groups having adipose tissue in the crest of the neck with or without hemorrhage (AH and NH groups, respectively). Blood biochemical tests (Alb, TP, T-bil, GOT, GPT, LDH, T-cho, and BUN) and an epidemiological survey (age, gender, weight, origin, breed, BCS, CNS, and hoof disease) were performed. T-bil tended to be high, while the other parameters were normal. Weight, BCS, and CNS were higher in the AH group (P<0.05). GOT was lower in the AH group (P<0.05). It was suspected that the horses in the AH group had lipomatosis. It was assumed ...
White SD.Pruritus in the horse may be due to several causes, the most common being a hypersensitivity response to salivary proteins in the Culicoides genera, which may coexist with atopic dermatitis, also known as an environmental allergy to pollens, molds, dust, storage mites, etc. Less common etiologies are food allergy and contact allergy, the latter often caused by owners applying various products to the skin. Other ectoparasites, such as Chorioptes mites, may also initiate pruritus. Secondary bacterial infections (usually Staphylococcus spp) may be pruritic in and of themselves. This article revie...
Perryman LE, McGuire TC.Combined immunodeficiency in horses is a genetic disorder in which there is a defect in the production of committed B and T lymphocytes. In this study, peripheral blood mononuclear leukocytes from foals with combined immunodeficiency were examined for their capacity to stimulate and respond in one-way mixed lymphocyte cultures. Irradiated cells from combined immunodeficient foals were uniformly capable of stimulating cells from unrelated horses. However, none were able to respond to allogeneic stimulation. Examination of cells from known carrier horses revealed no difference in capacity to sti...
Barbosa JD, Lins AMC, Bomjardim HDA, Silveira NDSES, Barbosa CC, Beuttemmuller EA, Brito MF, Salvarani FM.An investigative and epidemiological study was carried out for equine herpesvirus type 1 (HVE-1) in 10 outbreaks of neurological disease from different farms in the state of Pará, Brazil. 25 horses were studied: six male and 19 females, aged between one and 13 years. A necropsy of six horses was performed, and the others recovered either with or without treatment (T1-vitamin B1 + dexamentasone; T2-vitamin B1 + flunixim meglumine). Animals that received treatment recovered after eight days. The main clinical signs observed were motor incoordination, progressive paresis, thoracic and/or pelvic ...
Hobbs KJ, Johnson PJ, Wiedmeyer CE, Schultz L, Foote CA.Limited information is available regarding endothelial glycocalyx degradation during sepsis in horses. Plasma syndecan-1 concentrations are increased in consequence of sepsis in other species and have been useful for prognostication. Objective: To determine whether plasma syndecan-1 levels are increased in adult horses affected with sepsis. Methods: Retrospective cohort study. Methods: Adult horses were assigned to one of three groups based on results of physical and laboratory examinations, clinical diagnosis, and results of previously described SIRS classification: Group 1 horses included he...
Satué K, Gardon JC, Muñoz A.The process of fibrin clot formation is a series of complex and well-regulated reactions involving blood vessels, platelets, procoagulant plasma proteins, natural inhibitors, and fibrinolytic enzymes. Vasculitis can be caused by a variety of different agents as bacteria, viruses, protozoal, rickettsial organisms, toxic, drugs, medications, and neoplasms. The most common cause of vasculitis is the purpura hemorrhagica, which is associated with exposure to Streptococcus equi ssp. equi or less commonly, equine influenza. Deficiencies or defects of the hemostatic components may result in bleeding ...
Kang H, Lee GKC, Bienzle D, Arroyo LG, Sears W, Lillie BN, Beeler-Marfisi J.Alveolar macrophages (AMs) are the predominant innate immune cell in the distal respiratory tract. During inflammatory responses, AMs may be supplemented by blood monocytes, which differentiate into monocyte-derived macrophages (MDMs). Macrophages play important roles in a variety of common equine lower airway diseases, including severe equine asthma (SEA). In an experimental model, an inhaled mixture of Aspergillus fumigatus spores, lipopolysaccharide, and silica microspheres (FLS), induced SEA exacerbation in susceptible horses. However, whether equine AMs and MDMs have differing immunopheno...
Gargiulo AM, Pedini V, Ceccarelli P.The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha-...
Volland-Francqueville M, Sabbah A.Recurrent or chronic urticaria seems to be a food allergy in thoroughbred race-horses during the training season. In resistant cases, allergologic techniques will be required to determine aetiology. Intradermal skin tests with fresh allergenic food may cause syndromic reaction as urticaria and akin to enteritis in some horses. In most cases, an elimination of the allergen responsible brings a rapid and long-lasting result. Study about 22 cases.
Tapprest J, Foucher N, Linster M, Laloy E, Cordonnier N, Amat JP, Hendrikx P.The French surveillance network for causes of equine mortality (Resumeq) was created in 2015 for the qualitative surveillance of equine mortality through the centralization in a national database of necropsy data and their subsequent epidemiological analysis. It was designed to identify the causes of equine mortality, monitor their evolution over time and space, and detect emerging diseases as early as possible. Resumeq is an event-based surveillance system involving various players and structures. It is organized around a steering body, a scientific and technical support committee and a coord...
Nielsen MK, Martin AN, Scare JA, Steuer AE.Cyathostomins are pervasive parasites of equids across the world. Larval stages encyst in the mucosa of the cecum, ventral and dorsal colon and can induce an inflammatory response leading to larval cyathostominosis, a life-threatening generalized typhlocolitis. Mucosal digestion is the only gold standard procedure for identifying and quantifying all larval stages. There is a lack of standardization of this technique and several aspects are ambiguous, such as precision of the method and the possibility of spatial variation of mucosal larval counts. The aim of this study was to estimate precisio...
Rashmir-Raven A, Lavagnino M, Sedlak A, Gardner K, Arnoczky S.Hereditary equine regional dermal asthenia (HERDA) is a genetic disorder of collagen resulting in fragile, hyper-extensible skin and ulcerative lesions. The predominance of skin lesions have been shown to occur on the dorsum of HERDA-affected horses. While this has been postulated to be due to increased exposure to sunlight of these areas, the precise pathological mechanism which causes this to occur is unclear. Objective: We hypothesized that an increase in collagenase activity, that has been associated with the exposure of dermal fibroblasts to sunlight, will significantly degrade the materi...
Strömberg B, Rejnö S.The clinical and radiologic features of osteochondritis dissecans in the knee and hock joint of horses are described. The material includes 91 horses, of which 43 had the lesion in one or both knee joints, and 48 in one or both hock joints. It was found that osteochondritis dissecans of the knee joint was more common than the one in the hock joint in thoroughbreds and halfbreds, while the lesion in the hock joint was most common in standardbred trotters. In the knee the lesion was most often located to the lateral trochlear ridge. In the hock joint the predilection site was the intermediate ri...
Webster JH, Baird JD, Gunawan M, Martin IC, Kelly JD.The susceptibility of a known thiabendazole-resistant population of small strongyles to anthelmintics of both benzimidazole and non-benzimidazole groups, was determined. In the first study, 42 horses infected with thiabendazole-resistant small strongyles were allocated to 6 groups. Treatment groups received one of the following anthelmintics: mebendazole, febantel, febantel plus trichlorphon, morantel tartrate, or a combination of thiabendazole, piperazine and trichlorphon. Morantel tartrate and the thiabendazole/piperazine/trichlorphon combination produced highly significant (p less than 0.00...
Siwińska N, Żak-Bochenek A, Paszkowska M, Karczewski M, Długopolska D, Haider W.Colic, a condition affecting the gastrointestinal tract of horses, manifests as severe pain and may be a life-threatening condition. It is possible to distinguish between an acute, disposable process, as well as recurrent colic symptoms (abdominal pain) caused by an ongoing chronic inflammatory process. This paper presents a retrospective analysis of the histopathological findings of duodenal and rectal samples taken from horses with recurrent colic, with the aim to determine the frequency and extent of inflammation. The samples, i.e., duodenal biopsy (60 samples) and rectal biopsy (17 samples...
Cox A, Stewart AJ.Insect Bite Hypersensitivity (IBH, Queensland itch, sweet itch, equine summer eczema) is the most common pruritic disease of horses. It is most often caused by sensitivity to the saliva of spp. of biting midges; however, it can also be caused by hypersensitivity to other insect species. The prevalence of IBH in horses is reported to be as high as 60% in some parts of the world. Due to the severe pruritus and effects of secondary self-trauma, IBH has animal welfare concerns, and there is currently no cure. Management of this condition is life-long, time consuming and costly. New grading system...
LeRoy BE, Knight MC, Eggleston R, Torres-Velez F, Harmon BG.A 14-year-old bay Thoroughbred gelding was presented for evaluation of a mass at the base of the tail. The mass had been present for 1 year, and recently had begun to increase in size. Additional masses were found around the eye and shoulder. A fine-needle aspirate of the tail-base mass revealed highly anaplastic round to polyhedral cells containing dark green to black cytoplasmic granules interpreted to be melanin. Histologically, the mass was composed of pleomorphic, poorly pigmented, round to polyhedral cells interpreted to be neoplastic melanocytes. With immunohistochemistry, the cells wer...
Hance SR, Robertson JT.A 5-year-old Thoroughbred gelding was examined because of a small axillary wound sustained 5 days earlier and had resulted in extensive subcutaneous emphysema. Three days after admission, the horse's respiratory rate had increased to 72 breaths/min, and the horse appeared anxious and distressed. Thoracic radiography revealed pneumomediastinum and severe bilateral pneumothorax. Tube thoracostomy was performed on both hemithoraxes. The drains were connected to one-way suction valves and suction devices to decompress the thorax. A nasopharyngeal catheter was inserted, and oxygen insufflation was ...
Lisowski ZM, Sauter KA, Waddell LA, Hume DA, Pirie RS, Hudson NPH.Intestinal macrophages are the largest group of mononuclear phagocytes in the body and play a role in intestinal innate immunity, neuroimmune interactions and maintaining intestinal homeostasis. Conversely, they also are implicated in numerous pathologies of the gastrointestinal tract, such as postoperative ileus and inflammatory bowel disease. As a result, macrophages could be potential therapeutic targets. To date, there are limited studies on the morphology and distribution of macrophages in the equine gastrointestinal tract (GIT). The aim of this study was to identify the location and abun...
Dixon PM, Railton DI, McGorum BC, Tothill S.One-hundred and forty-seven of 270 (54.4%) horses suffering from pulmonary disorders were given at least one re-examination including, clinical, bronchoscopic, pulmonary function and cytological examinations after treatment and a further 83 of these horses (30.7%) had their clinical progress assessed by verbal or written reports. These examinations and progress reports showed high levels of partial or total recovery for most pulmonary disease categories, including chronic obstructive pulmonary disease, infectious, S. zooepidemicus and undifferentiated pulmonary disease and lungworm infection g...
Gold JH, Schuder JC, Stoeckle H.The defibrillation effectiveness of 4-msec rectangular wave shocks was evaluated using myocardial electrodes with 25-kg dogs and (nominally) 100-kg calves, ponies, and pigs as part of an evaluation of the suitability of these animals as models for automatic implanted defibrillator research. The percent success of defibrillation attempts in dogs ranged from 44% with 4-A, 6-J shocks to 93% with 8-A, 16-J shocks. The success achieved in calves with scaled electrodes was uniformly lower and reached a maximum of 28% with 23-A, 107-J shocks. Pigs defibrillated with scaled electrodes at a success lev...
Jago RC, Scholes S, Mair TS, Pearson GR, Pirie RS, Handel I, Milne EM, Coyle F, Mcgorum BC.An accurate, minimally invasive, ante-mortem diagnostic test for equine grass sickness (EGS) is currently lacking. Although histological examination of haematoxylin and eosin-stained rectal biopsies for chromatolytic neurons is insensitive as a diagnostic test for EGS, we hypothesised that its diagnostic accuracy could be improved by immunolabelling for β-amyloid precursor protein (β-APP), which has increased expression in cranial cervical ganglia (CCG) neuronal perikarya in EGS. Objective: To develop a grading scheme for assessing the distribution and intensity of β-APP immunoreactivity wi...
Symons JE, Entwistle RC, Arens AM, Garcia TC, Christiansen BA, Fyhrie DP, Stover SM.To determine morphological and mechanical properties of trabecular bone of horses with a bone fragility syndrome (BFS; including silicate-associated osteoporosis). Methods: Cylindrical trabecular bone samples from the distal aspects of cadaveric third metacarpal bones of 39 horses (19 horses with a BFS [BFS bone samples] and 20 horses without a BFS [control bone samples]). Methods: Bone samples were imaged via micro-CT for determination of bone volume fraction; apparent and mean mineralized bone densities; and trabecular number, thickness, and separation. Bone samples were compressed to failur...
