The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Imagawa H, Tanaka T, Sekiguchi K, Fukunaga Y, Anzai T, Minamoto N, Kamada M.Electropherotypes (ET), serotypes, and subgroups of equine rotaviruses isolated from foals in Japan were determined. The ETs of 136 isolates from 1981 through to 1991 were divided into six groups: ET-A-ET-F. The ET-A, -B, -C, -D, -E, and -F were present in 3, 1, 121, 9, 1, and 1 strains, respectively. Representative viruses of ET-A, -B, -C, and -D were identified as serotype G3. Viruses of ET-E and -F were identified as serotypes G 10 and G 5, respectively. The four representative viruses of serotype G 3 did not belong to either subgroup I or II. The two viruses of serotypes G 5 and G 10 belon...
DeVico AL, Issel CJ, Le Grice SF, Payne SL, Montelaro RC, Sarngadharan MG.The immunogenicity of the equine infectious anemia virus (EIAV) reverse transcriptase (RT) was examined by immunoblot assay with recombinant EIAV RT. All of the 19 sera from EIAV-infected horses tested contained antibodies that recognized EIAV RT and directly inhibited the polymerase activity of the enzyme. An examination of sera obtained sequentially from two experimentally infected animals revealed that anti-RT antibodies arise early in infection and increase in level. The appearance of the antibodies correlated with progression toward the asymptomatic period of infection.
Fritsch R.Ultrasonography has established itself as an invaluable diagnostic aid in surgical diseases. In addition to the diagnosis of thoracic and abdominal disease, ultrasonography is increasing in importance in the examination of muscles, tendons and joints in small animals. In the horse, the application of the technique is being extended from tendon conditions to organ diseases. The optimal diagnostic information can only be achieved through the use of different scanner types.
Gospodarek E.Direct and intermediate hemolytic activity of 526 strains of Acinetobacter was investigated. Their ability to produce lipase and lecithinase was also studied. Measurements were performed parallely on human, horse, sheep and bovine erythrocytes. Direct hemolytic activity was exhibited by 16% of tested strains (17 out of 24 strains of A. haemolyticus). Human, sheep and bovine erythrocytes were useful for testing the hemolytic activity of Acinetobacter. The hemolysis was occurring faster and was visible more frequently during incubation at 37 degrees C. Indirect hemolytic activity was observed in...
Durden LA, Linthicum KJ, Monath TP.Pools of adult female chicken mites, Dermanyssus gallinae (De Geer), were allowed to feed on chicks that had been inoculated with eastern equine encephalomyelitis (EEE) virus and that had a viremia level of 10(6.2)-10(6.6) plaque-forming units per milliliter of blood. Virus remained detectable by plaque assay in samples of these mites for 30 d after the infectious blood meal. Virus was not recovered from any of 151 progeny of virus-exposed female mites. Mites that had fed on viremic chicks were allowed to feed on naive chicks 3, 7, 11, 15, or 30 d later. EEE virus was transmitted to chicks by ...
Baba SS, Olaleye OD, Ayanbadejo OA.A sero-epidemiological survey of African horse sickness (AHS) virus in 261 animals which included 96 camels, 81 horses, 80 dogs and 4 donkeys was carried out in Nigeria. The animals had no history of vaccination against AHS. Sera were tested by the haemagglutination-inhibition (HI) test for the presence of antibody against AHS virus. Of these, 77 (95.1%) horse, 4 (100%) donkey, 10 (10.4%) camel and 28 (35%) dog sera samples tested were recorded as positive. The prevalence of antibody in samples taken from horses in different regions was similar. The prevalence of antibody to AHS virus detected...
Pelegrino JL, Vázquez S, Morier L, Castillo A, Guzmán MG, Kourí G.We present the results attained in the identification of Eastern equine encephalomyelitis virus isolations in Vero and XL-2 cell systems, using a double-antibody ELISA technique and the indirect immunofluorescence method. The results attained through these two techniques coincided by 100% with identification through neutralization. With the former, the virus was detected within 6-8 hours after inoculation. Better results were attained with XL-2 cells.
Raisbeck MF, Dahl ER, Sanchez DA, Belden EL, O'Toole D.A review of Wyoming State Veterinary Laboratory records for 1947-1987 revealed no substantiated cases of naturally occurring selenosis. However, older reports attributed thousands of animal deaths to selenium each year in this area. Beginning in August 1988, cases of suspected selenosis and selenium deficiency were solicited from veterinarians and producers by announcements in various statewide livestock publications. As of August 1991, 4 cases (all horses) of naturally occurring selenosis have been confirmed. Clinical signs were most often referable to epithelial damage, e.g., hoof lesions an...
Popović N, Djuricić B, Valcić M.A study of literature concerning Lyme borreliosis related to animals was done. In the research work the epidemiology, pathogenesis, diagnosis and treatment of horses, cattle and dogs affected with Lyme borreliosis have been discussed. The clinical signs of Lyme borreliosis in horses are: chronic weight loss, sporadic lameness, laminitis, low grade fever, swollen joints, muscle tenderness and anterior uvetitis. In addition to these clinical sings, neurological sings such as depression, behavioral changes, dysphagia and encephalitis can be seen in chronic cases. Cattle affected with acute Lyme b...
Hawkins JF, Schumacher JS, McClure SR, Light GS.Small intestinal incarceration through the lateral ligament of the urinary bladder was diagnosed in a 14-year-old, 569-kg, castrated Quarter Horse. The incarceration was corrected by ventral midline celiotomy. Approximately 70 cm of the middle portion of the jejunum was resected and end-to-end, single-layer anastomosis was performed. After surgery, the horse developed signs of adynamic ileus and lameness in the right forelimb. The horse developed laminitis in all 4 feet within 24 hours of surgery. The horse was euthanatized because of poor prognosis for survival. At necropsy, a 4.5-cm rent was...
Alstad AD, Sahu SP, Pedersen DD, Saari DA, Kawaoka Y, Webster RG.An influenza virus, A/equine/Alaska/1/91 (H3N8), was isolated from horses from Alaska with an acute respiratory infection. Pathogenic and serologic studies revealed that this virus is similar to previously isolated equine H3N8 influenza viruses. Antigenic analyses utilizing hemagglutination inhibition and neuraminidase inhibition assays indicated an antigenic drift from the prototype equine H3N8 influenza virus, A/equine/Miami/1/63. Partial sequence analysis of the A/equine/Alaska influenza virus indicated that each of 8 gene sequences are of equine origin.
Schultheiss PC, Collins JK, Carman J.An indirect immunoperoxidase (IP) procedure using the avidin-biotin-peroxidase complex detection technique was developed to detect viral equine herpesvirus-1 (EHV-1) antigen in formalin-fixed paraffin-embedded tissues from aborted equine fetuses. The procedure was applied to liver, lung, and other tissues from 20 cases of confirmed or suspected EHV-1-induced abortions. Specific staining was observed in tissue sections from EHV-1-infected fetuses. Positive IP staining was present in tissues of 7 cases that were also positive by fluorescent antibody (FA) and virus isolation (VI) and that had typ...
van de Moer A, Rice M, Wilks CR.A type-specific monoclonal antibody was produced by immunizing mice with purified equid herpesvirus-1 (EHV-1). The EHV-1 specific mAb reacted with all the EHV-1 strains tested so far by indirect ELISA, immunofluorescence, and immunoperoxidase tests. No reactions were detected with the EHV-4, EHV-2, or EHV-3 strains tested. The indirect immunofluorescence and immunoperoxidase tests showed that the nuclei of infected cells were predominantly stained by this mAb. Triton treatment of the virus and immunogold labeling experiments indicated that the nucleocapsid of EHV-1 was the target antigen of th...
Brocard P, Pfister K.The combined drug Mebendazole plus Trichlorfon (Telmin plus Trichlorfon, Janssen Pharmaceutica, Beerse/Belgium) has been tested in a field trial against naturally acquired Gasterophilus spp. infestations in horses. 44 foals (1 to 1.5 years old, 350-450 kg body-weight) originating from different endemic areas of Switzerland, have been randomly allocated to two groups as follows: 28 foals were treated with Mebendazole plus Trichlorfon, 16 animals served as untreated controls. The drug (paste) was administered and dosed according to the user's instruction. Macroscopic examinations of the digestiv...
Rojas G, Vargas M, Robles A, Gutiérrez JM.Twenty batches of polyvalent antivenom produced at the Instituto Clodomiro Picado were analyzed for turbidity, both before and after freezing-thawing and lyophilization. Eight batches became turbid upon freezing-thawing, and this change correlated with high levels of cholesterol, triglycerides and lipoproteins, especially beta-lipoprotein. Since normal horse serum does not become turbid after freezing-thawing, despite the fact that it has high lipoprotein levels, the possibility was raised that phenol, used as a preservative during serum fractionation, might affect lipoproteins, inducing the a...
Held JP, McCracken MD, Toal R, Latimer F.Aspermia was diagnosed in a 12-year-old Thoroughbred stallion with generalized lymphosarcoma. Invasion of the epididymus by neoplastic cells caused thickening and enlargement of both epididymes. The testes were not affected. The nodular ultrasonographic architecture was similar to that in previously reported cases of infectious epididymitis.
Home WA, Ford JE, Gibson DM.Analysis of 10 cDNA encoding lambda L chains of horse Ig indicated that this species may employ a relatively small number of variable region (V lambda) genes in the splenic B cell population. The V lambda sequences of all of the cDNA analyzed were closely related (> 88% identity at the nucleotide level) and were characterized by a deletion of the amino acid residue at position 3 compared with V lambda sequences so far described in other species. The 10 V lambda sequences could be grouped into three groups, V lambda 1 to V lambda 3, on the basis of a number of linked substitutions. Sequences...
Knowles DP, Kappmeyer LS, Stiller D, Hennager SG, Perryman LE.Horses infected with Babesia equi were previously identified by the presence of antibodies reactive with a merozoite surface protein epitope (D. P. Knowles, Jr., L. E. Perryman, L. S. Kappmeyer, and S. G. Hennager. J. Clin. Microbiol. 29:2056-2058, 1991). The antibodies were detected in a competitive inhibition enzyme-linked immunosorbent assay (CI ELISA) by using monoclonal antibody 36/133.97, which defines a protein epitope on the merozoite surface. The gene encoding this B. equi merozoite epitope was cloned and expressed in Escherichia coli. The recombinant merozoite protein, designated equ...
Brück I, Hesselholt M.The results of clinical, ultrasonic, post mortem examinations and concrement analysis of a case with nephrolithiasis in a horse are described. Problems of diagnosis, etiology and occurrence of nephroliths in the horse are discussed.
Schöl H, Beelitz P, Gothe R.Trichomonads of the oral cavity were found in 9 of 60 investigated horses. Apart from dental tartar, the oral cavity showed no clinical signs in all positive horses. The clinical investigation of these horses additionally revealed colic in 4 and coughing in 4 horses as well as lumbago in 1 animal. By means of scanning electron microscopy the trichomonads were shown to be round or piriform with an average length of 7.6 microns and greatest width of 6.3 microns. They had 4 anterior flagella with an average length of 8.3 microns, an undulating membrane measuring 8.7 microns with no trailing flage...
Lavach JD.The diseases included in this article constitute a wide range of maladies that affect the horse. Certainly, the diseases that are known today to produce ocular lesions are just a few of what will be discovered if attending veterinarians always examine the eyes of patients with systemic diseases.
Peloso JG, Coatney RW, Caron JP, Steficek BA.An obstructive enterolith was diagnosed in an 11-month-old 68-kg miniature horse with a 24-hour history of mild, intermittent colic. Abdominal radiography revealed gas distention of the cecum and the right and left ascending colon, and a radiodense elliptical structure in the area of the left kidney. During exploratory laparotomy, the right dorsal colon was noticed to contain ecchymotic hemorrhage and generalized discoloration in the portion proximal to the location of the enterolith. While exteriorizing the ascending colon, it ruptured caudal to the diaphragmatic flexure in the right dorsal c...
Palmer JE, Benson CE, Whitlock RH.Eighteen ponies were inoculated IV with Ehrlichia risticii-infected P388D1 mouse monocyte cells. Twenty-four hours after onset of fever (rectal temperature > 38.8 C), 9 ponies were treated with oxytetracycline (6.6 mg/kg of body weight, IV, q 24 h) for 5 days. The remaining 9 ponies served as infected nontreated controls. Mean scores of the following variables were not significantly different between groups on the day treatment was begun: rectal temperature, diarrhea, borborygmal sounds, feed intake, mental attitude, and evidence of a hyperresonant area in the abdomen. All ponies were observed...
Blanchard PC, Filkins M.Cryptococcus neoformans was the causative agent of pneumonia in a 9-month-old equine fetus aborted by a healthy American Paint mare. Endometritis was diagnosed on biopsy, and vaginal specimens obtained for culture were Cryptococcus-positive 1 month following abortion but not 5 months after abortion. Infection resolved without treatment between 1 and 5 months after abortion, and the mare was bred the following year and delivered a live premature foal without evidence of Cryptococcus infection.
Maddison JE.Fifty-nine reports of suspected adverse drug reactions (ADRs) were received by the Adverse Drug Reaction Subcommittee of the Australian Veterinary Association from February 1991-March 1992 inclusive. The number of reports received/number of animals involved per species was: dogs (23/24); cats (20/30); horses (4/4); cattle (7/10); sheep (3/745); poultry (1/580); pigs (1/8). Of these, 38 (64%) were classified as definite ADRs and 9 (15%) as probable ADRs. In 10 (17%) reports an ADR could not be substantiated or there was insufficient information available to make a decision. Two reports involved...
Moore C, Stefanovski D, Luethy D.Antemortem definitive diagnosis of lymphoma in horses is often difficult. Thymidine kinase 1 (TK1) assay is a potentially useful biomarker for lymphoma in horses. Objective: To report the clinical performance of a commercially available TK1 assay for diagnosis of lymphoma in horses. We hypothesized that there would be no association between serum TK1 activity and a diagnosis of lymphoma in horses. Methods: Forty-two hospitalized horses, 14 with a definitive diagnosis of lymphoma, 4 with other neoplasia, and 24 with inflammatory disease. Methods: Retrospective medical record review, groups were...
Sleeper MM, Palmer JE.The clinical and echocardiographic findings in a 19-h-old female foal with a ventricular septal defect, patent foramen ovale, patent ductus arteriosus, and complete transpositon of the great vessels are described. Clinical signs were suggestive of complex congenital heart disease and echocardiography of the foal allowed definitive diagnosis prior to postmortem.
Ülke ÇG, Deniz SI, Nureddin Ç.Metacarpal tendon diseases are important problems that may cause a decrease in performance and even may finish sport life in equine athletes. In this study, it was aimed to evaluate the ratio of return to races and the time of staying away from races and also to detect the prognostic value of ultrasonographic findings in Thoroughbred and Arabian racehorses with metacarpal flexor tendon injury or peritendonitis. Of 120 cases, 84 (70.0%) returned to races. Among these, 82.1% had tendonitis (69/84) and 17.9% peritendonitis (15/84). Among the cases being unable to return to races, 91.7% had tendon...
Kramer JW, Nickels FA, Bell T.Examination of effusions from body cavities must include a search for neoplastic as well as inflammatory cells. Neoplastic cells found in the thorax are generally derived from adenocarcinomas or mesotheliomas. Mesotheliomas are relatively uncommon and the neoplastic cells found in effusions are difficult to differentiate from activated cells in inflammatory effusions. An ante-mortem diagnosis of mesothelioma was made in a mare on the basis of the large volume of fluid produced, the pleomorphic mesothelial cells, the polyp formation and the absence of PAS staining material after digestion of th...
Ollivett TL, Divers TJ, Cushing T, Priest H, Dawson DR, Peters R, Stokol T.Severe acute pancreatitis (SAP) in foals is rare and treatment has not been documented. This paper describes the clinical, haematological and ultrasonographic findings as well as attempted treatment of SAP in two 5-day-old Appaloosa fillies. Clinical signs, including colic, diarrhoea and coma, may be mistaken for sepsis or neonatal encephalopathy. Hyperlipaemic serum and peritoneal fluid, and elevated serum and peritoneal fluid amylase and lipase activities aided the diagnosis. Severe acute pancreatitis should be included as a differential in an acutely ill foal with diarrhoea, colic, cerebral...
Kolb DS, Klein C.Congenital hydrocephalus has been reported for a number of horse breeds, and for Friesian horses this condition has been associated with a nonsense mutation of B3GALNT2. We report the first case of congenital hydrocephalus associated with the said mutation in a Belgian draft horse. Genetic testing and consideration of the testing results in breeding programs are warranted. Hydrocéphalie congénitale chez un cheval de trait Belge associée à une mutation non-sens de B3GALNT2. L’hydrocéphalie congénitale a été signalée pour plusieurs races de chevaux et, pour les chevaux Frisons, cette ...
Baba AI, Gaboreanu M, Rotaru O, Kwieczinsky R.Malignant melanomas in 5 horses, 1 calf, 1 cow and 2 pigs were described. The disease, in white or gray horses, was tegumentally located and generalized in the organs of the abdominal cavity. Microscopically, dendritic and fusiform pigment cells and multinucleated cells were identified. In the hypophysis there microcysts and in one case a hypophyseal adenoma were encountered. Electronmicroscopically, differentiated melanophores and melanophages were also found. The mature melanosomes were intensely black and the elementary granules concentrically and lamellarly arranged. In cattle, the general...
Slivinska K, Karbowiak G, Gawor J, Wróblewski Z, Jaworski Z, Jastrzębska E, Demeshkant V.The influence of internal and external parasites on the health of Polish konik horses housed in different types of management strategies in Poland is discussed. This study includes consolidated data of different authors from the past 50 years, supplemented by results of more recent research. A total of 38 species of helminths (i.e., 37 Nematoda and one Cestoda) and five Diptera species were recorded from the horses. Protozoan parasites, Cryptosporidium spp. and Theileria equi, and the Rickettsiales, Anaplasma phagocytophilum, were observed for the first time in Poland.
Fordyce PS, Edington N, Bridges GC, Wright JA, Edwards GB.In 27 potential neuropathies an enzyme-linked immunosorbent assay, using P2 preparations from either bovine or equine myelin, detected all cases of cauda equina neuritis in which there was caudal involvement. The test was of limited value in differentiating neuropathies involving only cranial or other peripheral nerves.
Edmonds JD, Horohov DW, Chapmat MR, Pourciau SS, Antoku K, Snedden K, Klei TR.This study was performed to test the hypothesis that immunity to heterologous vaccination would improve when the parasites were removed. It was also expected that parasitised ponies would exhibit a biased Th2 cytokine response to KLH immunisation. Helminth parasites are common in horses even in the era of highly effective broad-spectrum antiparasiticides. These parasites have been shown to alter the outcome to heterologous immunisation in a number of host species. The effect of gastrointestinal parasites on heterologous vaccination has not been addressed in equids. In the current study, humora...