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.
Mair TS.Eight horses with Grade 3b rectal tears of the peritoneal part of the rectum or small colon were treated by a combination of medical therapy and dietary manipulation. All of the horses developed septic peritonitis during the course of treatment. Medical therapy consisted of a combination of penicillin, gentamicin and flunixin meglumine administered parenterally, metronidazole administered orally and liquid paraffin administered by nasogastric tube. Some horses also received fluid and electrolyte therapy i.v., plasma and heparin i.v. All horses were maintained on a laxative diet. Six of the 8 h...
Santschi EM, Slone DE, Embertson RM, Clayton MK, Markel MD.The purpose of our study was to determine the types of lesions that cause colic in juvenile Thoroughbreds, factors associated with these lesions and the subsequent survival and athletic performance of the juveniles. The age of juvenile Thoroughbreds requiring surgical exploration for abdominal pain has an influence on the type of lesion causing colic. The short-term survival rate (discharge from the hospital) after colic surgery for foals was 85% and was strongly influenced by the lesion causing colic. Thirteen percent of juveniles recovered from the first surgery experienced another severe co...
Edwards GB, Kelly DF, Proudman CJ.Twenty-two horses with colic, referred to the University of Liverpool Equine Hospital (1992-1998), were found at laparotomy to have a partial obstruction of the large colon caused by a segmental mural lesion located in the left dorsal colon. The decision to take the horses to surgery was based on rectal examination findings of secondary impaction and mural oedema of the large colon and turbid peritoneal fluid containing large numbers of neutrophils obtained by paracentesis. The affected segment of colon showed oedema and serosal changes varying from erythema to well-defined necrosis. These pat...
Lyons ET, Drudge JH, Tolliver SC.Over the past few years, cyathostomiasis has become increasingly recognized as a clinical problem of horses in the United States. Clinical cyathostomiasis has been reported frequently in Europe for a considerable time. This clinical syndrome is usually related to the sudden release of large numbers of the larval stages of small strongyles from the mucosa of the large intestine. Typical clinical signs include diarrhea, ventral abdominal edema, pyrexia, colic, weight loss, and poor body condition. Hypoalbuminemia and the presence of large numbers of small strongyles being passed in the feces are...
Ryan MP, McAuliffe O, Ross RP, Hill C.Lacticin 3147 is a broad-spectrum, two-component, lanthionine-containing bacteriocin produced by Lactococcus lactis DPC3147 which has widespread food and biomedical applications as a natural antimicrobial. Other two-component lantibiotics described to date include cytolysin and staphylococcin C55. Interestingly, cytolysin, produced by Enterococcus faecalis, has an associated haemolytic activity. The objective of this study was to compare the biological activity of lacticin 3147 with cytolysin. The lacticin 3147-encoding determinants were heterologously expressed in Ent. faecalis FA2-2, a plasm...
Deegen E, Venner M.In 10 horses, which were referred to the clinic with the suspicion of disorders of the gastrointestinal tract, gastroscopy revealed a gastric tumour. In ten cases the diagnosis of a squamous cell carcinoma was made on the basis of histology of biopsies or autopsy. The tumour always derived from the non-glandulary mucosa. The horses showed various clinical symptoms. All patients had a hypoalbuminemia and a hyperglobulinemia in the serum electrophoresis. This suggests that a gastric tumour can be suspected intra-vitam even without gastroscopy of the patient.
McDonnell A, Love S, Tait A, Lichtenfels JR, Matthews JB.Three nucleotide data sets, one nuclear (ITS-2) and two mitochondrial (COI and l-rRNA), have been investigated in order to determine relationships among species of Strongylinae and Cyathostominae, intestinal parasites of the horse. The data exhibited a strong mutational bias towards A and T and in the COI gene, silent sites appeared to saturate rapidly partly due to this substitution bias. Thus, the COI gene was found to be less phylogenetically informative than the l-rRNA and ITS-2 genes. Combined analysis of the l-rRNA and ITS-2 genes supported a monophyletic clade of the cyathostomes with T...
Bollinger A, Eckert J, Rüttimann B, Becker F.Intermittent claudication (IC) due to arterial occlusive disease was first diagnosed by the French veterinary surgeon Jean-François Bouley jeune in a horse drawing a cabriolet in the streets of Paris as early as 1831. The animal was repeatedly exercised and always started to limp with the hind legs at similar work loads. Autopsy revealed partially thrombosed aneurysm of the abdominal aorta and occlusions of both femoral arteries which were correctly identified as the cause of IC. In 1858 the famous neurologist Jean-Martin Charcot working at the Salpêtrière in Paris first discovered the cond...
Ma Z, Mizukoshi T, Khatlani TS, Okuda M, Onishi T.The serum amyloid A (SAA) protein is a characteristic and sensitive acute phase reactant in all vertebrates investigated. We molecularly cloned the equine cDNA encoding SAA from the liver of a healthy horse by polymerase chain reaction (PCR). The cloned cDNA is 480 bases in length, and contains an open reading frame (ORF) of 387 nucleotides encoding a precursor SAA protein of 128 amino acids. The precursor of horse SAA seems to have an 18-residue signal peptide and differs from the reported amino acid sequences of the horse SAA by substitution of valine at residue 81. It shows high homology wi...
Sheoran AS, Nally JE, Donahue JM, Smith BJ, Timoney JF.Leptospira-specific antibody isotypes in sera of late term equine fetuses aborted due to Leptospira interrogans serovar pomona-type kennewicki infection were characterized and compared with those of their dams. IgM was the dominant Leptospira-Specific isotype in both fetuses and mares. However, IgGa was the isotype in highest concentration in petal sera and strong Leptospira-specific IgGa but no IgGb and little or no IgG(T) were detected. In contrast, although IgGb was quantitatively the dominant isotype in mares serum, Leptospira-specific serum IgG in aborting mares was dominated by IgG(T) bu...
de Clercq T, Verschooten F, Ysebaert M.A collection of 69 isolated navicular bones, normal or affected with navicular disease, was examined radiographically using dorsopalmar, lateromedial and palmaroproximal-palmarodistal views. Radiographic findings on each view were recorded. A radiographic diagnosis of normality or navicular disease was made, first on each view separately and afterwards based on the combination of the 3 views. Forty-four navicular bones were considered radiographically normal and 25 navicular bones had distinct signs of radiographic navicular disease. The dorsopalmar and the lateromedial views of each navicular...
Hahn CN, Mayhew IG.The effect of an ocular administration of the alpha-1 adrenergic agonist phenylephrine was studied in 23 cases of grass sickness and 12 control horses. In the horses with grass sickness there was a significantly greater mean increase in the size of the palpebral fissure, as measured by the change in the angle of the eyelashes to the head observed from a frontal view.
MacLeay JM, Valberg SJ, Pagan JD, Xue JL, De La Corte FD, Roberts J.To determine the effects of 3 rations (low grain, fat, high grain) on plasma creatine kinase (CK) activity and lactate concentration in Thoroughbred horses with recurrent exertional rhabdomyolysis (RER). Methods: 5 Thoroughbreds with RER and 3 healthy Thoroughbreds (control horses). Methods: Rations were formulated to meet (low-grain and fat rations) or exceed (high-grain ration) daily energy requirements. Each ration was fed to horses in a crossover design for 3 weeks. Horses were exercised on a treadmill Monday through Friday; maximum speed on Monday and Friday was 11 m/s (6% slope), on Tues...
Yasuda R, Kawano J, Onda H, Takagi M, Shimizu A, Anzai T.To determine patterns of methicillin-resistant staphylococci isolated from apparently healthy horses. Methods: 44 horses from 8 riding clubs in Japan. Methods: Methicill in-resistant staphylococci were isolated from the skin or nares, using a selective medium containing a beta-(symboric) lactam antibiotic, ceftizoxime. Clonality of isolates was determined by use of pulsed-field gel electrophoresis. Detection of mecA, mecl, and mecR1 genes was accomplished by use of polymerase chain reactions. Results: Of the 44 horses, 13 (29.5%) yielded 15 isolates of methicillin-resistant staphylococci. The ...
Patterson-Kane JC, Tramontin RR, Giles RC, Harrison LR.A 14-year-old Thoroughbred gelding with a history of acute onset of hematuria was presented for necropsy. Transitional cell carcinoma of the urinary bladder with intra-abdominal dissemination was diagnosed. Tumor masses were observed on the splenic capsule and surrounding the distal abdominal aorta. Tumor cells showed diffuse cytoplasmic reactivity for cytokeratin but were negative for epithelial membrane antigen, carcinoembryonic antigen, tumor-associated glycoprotein 72, and vimentin.
Haechler S, Van den Ingh TS, Rogivue C, Ehrensperger F, Welle M.Congenital hepatic fibrosis with autosomal recessive or dominant inheritance has been described in humans, cats, piglets, and dogs. In horses, only two cases of congenital hepatic fibrosis have been previously reported. This retrospective study of records from the Institute for Animal Pathology, University of Berne, identified 30 foals with liver lesions compatible with congenital hepatic fibrosis. Anamnestic data revealed clinical signs of severe liver injury in most affected animals. Pathologic examination showed severely enlarged, firm livers with thin-walled cysts. Histologically, the live...
Guy JS, Breslin JJ, Breuhaus B, Vivrette S, Smith LG.A coronavirus was isolated from feces of a diarrheic foal and serially propagated in human rectal adenocarcinoma (HRT-18) cells. Antigenic and genomic characterizations of the virus (isolate NC99) were based on serological comparison with other avian and mammalian coronaviruses and sequence analysis of the nucleocapsid (N) protein gene. Indirect fluorescent-antibody assay procedures and virus neutralization assays demonstrated a close antigenic relationship with bovine coronavirus (BCV) and porcine hemagglutinating encephalomyelitis virus (mammalian group 2 coronaviruses). Using previously des...
Kablack KA, Embertson RM, Bernard WV, Bramlage LR, Hance S, Reimer JM, Barton MH.Historical, physical and diagnostic data were reviewed retrospectively in 31 equine neonates with uroperitoneum. Gender predilection was not observed, and classic electrolyte abnormalities were seen in less than 50% of the cases. Aetiologies for uroperitoneum have been well described, but this review found that septicaemia/severe illness played a crucial role the outcome of uroperitoneum. Approximately half the individuals with uroperitoneum had positive sepsis scores. Foals receiving fluid therapy were more likely to be septic and to have normal electrolyte concentrations. Ultrasonographic fi...
Suzuki Y, Ito T, Suzuki T, Holland RE, Chambers TM, Kiso M, Ishida H, Kawaoka Y.The distribution of sialic acid (SA) species varies among animal species, but the biological role of this variation is largely unknown. Influenza viruses differ in their ability to recognize SA-galactose (Gal) linkages, depending on the animal hosts from which they are isolated. For example, human viruses preferentially recognize SA linked to Gal by the alpha2,6(SAalpha2,6Gal) linkage, while equine viruses favor SAalpha2,3Gal. However, whether a difference in relative abundance of specific SA species (N-acetylneuraminic acid [NeuAc] and N-glycolylneuraminic acid [NeuGc]) among different animal...
Hinton TM, Li F, Crabb BS.Equine rhinitis A virus (ERAV) has recently been classified as an aphthovirus, a genus otherwise comprised of the different serotypes of Foot-and-mouth disease virus (FMDV). FMDV initiates translation via a type II internal ribosomal entry site (IRES) and utilizes two in-frame AUG codons to produce the leader proteinases Lab and Lb. Here we show that the ERAV 5' nontranslated region also possesses the core structures of a type II IRES. The functional activity of this region was characterized by transfection of bicistronic plasmids into BHK-21 cells. In this system the core type II structures, ...
Várady M, Königová A, Corba J.The present study included 19 stud farms, including 243 horses, that were investigated for the occurrence of anthelmintic resistant cyathostomes. The number of horses on the farms varied from nine to more than 100, and horses of all ages were included. A minimum of seven horses were used for faecal egg count reduction (FECR) tests. The anthelmintics included were: fenbendazole (paste formulation), ivermectin (paste formulation) and pyrantel (powder). Resistance to benzimidazoles was detected on 14 farms, with FECR values ranging from 65.1 to 86.3%. Larval cultures after fenbendazole treatment ...
Bureau F, Delhalle S, Bonizzi G, Fiévez L, Dogné S, Kirschvink N, Vanderplasschen A, Merville MP, Bours V, Lekeux P.In most cells trans-activating NF-kappaB induces many inflammatory proteins as well as its own inhibitor, IkappaB-alpha, thus assuring a transient response upon stimulation. However, NF-kappaB-dependent inflammatory gene expression is persistent in asthmatic bronchi, even after allergen eviction. In the present report we used bronchial brushing samples (BBSs) from heaves-affected horses (a spontaneous model of asthma) to elucidate the mechanisms by which NF-kappaB activity is maintained in asthmatic airways. NF-kappaB activity was high in granulocytic and nongranulocytic BBS cells. However, NF...
Ceci L, Carelli G.This paper reviews basic information on the knowledge of tick-borne diseases, babesiosis, anaplasmosis and theileriosis, in horses, cattle, sheep and goats in Italy with particular reference to the southern part of the country. It is stressed that there is limited knowledge about the parasite species present, their vectors, distribution, prevalence and impact on livestock production and there is the need to assess their epidemiology. A study carried out in the Apulia region to assess the prevalence of Anaplasma marginale infection in 1,648 cattle showed a seroprevalence of 17% using the Card A...
Kosuge J, Goto Y, Shinjo T, Anzai T, Takatori K.Sixty-six new and used samples of horse bedding materials: 60 rice straws, 2 wheat straws, 2 timothy hays and 2 wood chips, were collected from horse breeding stables of 33 farms in Japan and examined for the presence of Emericella nidulans (E. nidulans; anam. Aspergillus nidulans). The incidence of E. nidulans in the bedding materials was 75.8% and there was no significant difference in detection of the fungus between the new and used materials (25 out of the 33 samples, respectively). The growth of E. nidulans isolated in sterilized rice straw culture was accelerated by the addition of water...
DeBowes RM, Yovich JV.Foot-associated lamenesses are common diagnostic challenges for the equine practitioner. This article reviews the commonly occurring penetrating and concussive solar injuries of the equine foot. Diagnostic and therapeutic approaches for the management of these conditions are suggested. With proper treatment, many of these serious injuries will show excellent results.
Sheahan BJ, Wilkins PA, Lascola KM, Martin V, Po E.Prior studies have shown the prognostic utility of measuring L-lactate in critically ill neonatal foals, both as single (at admission) and serial measurements. Greater prognostic sensitivity and specificity may be achieved by use of the area under the L-lactate versus time curve (LACArea ) over the first 24 hours of hospitalization, which captures both severity and duration of hyperlactatemia. Prior to application of this concept in sick equine neonates, a reference interval for LACArea should be determined. Methods: The concentration of lactate [LAC] was measured in blood obtained via direct ...
Favaro PF, Reischak D, Brandao PE, Villalobos EMC, Cunha EMS, Lara MCC, Benvenga GU, Dias RA, Mori E, Richtzenhain LJ.The equine influenza virus (EIV) H3N8 subtype is responsible for all EIV outbreaks worldwide while the H7N7 subtype is less pathogenic and is considered extinct as it has not been confirmed in outbreaks since 1980. Although EIV is enzootic in Brazil, few reports describe the actual EIV antibody status in the country. The aims of this study were: - to evaluate the efficiency of different serum treatments described by the World Organisation for Animal Health (OIE) and the World Health Organization (WHO) to remove non-specific haemagglutination inhibitors for the haemagglutination inhibition (HI)...
Sandberg K, Juneja RK.Evidence for close linkage between the structural loci for albumin and Gc protein in the horse was presented. A recombination frequency (c) of 0.009 +/- 0.006 (95% confidence limits: 0.001 less than c less than 0.032) was estimated. These results were based on a study of a large sire family comprising 223 offspring from informative matings. No evidence of linkage disequilibrium was observed in one horse population studied.
Auer JA, Martens RJ.Valgus deformities were created in 6 pony foals by hemicircumferential transection of the periosteum and periosteal stripping (HCTP and PS) just proximally to the distal physis on the medial side of 1 radius (principal thoracic limb). The opposite thoracic limb served as a control. One month after this surgical procedure was done, the limbs were radiographed and the angle of deviation was determined. All horses developed a valgus deformity of the principal limb. In an effort to correct the acquired valgus deformity, the 2nd surgical procedure was performed--HCTP and PS on the lateral aspect of...
Tasker JB.Reference (normal) ranges were established for clinical chemistry results obtained from the Coulter Chemistry instrument on specimens from dogs, cats, horses, and cattle. These results, in general, are very similar to those reported in the current veterinary literature. The specimens obtained from horses and cows were subdivided according to age and lactation status, respectively. Significant differences were noted between the subgroups in the results of certain tests.
Christensen BW, Roberts JF, Pozor MA, Giguere S, Sells SF, Donahue JM.A 4-year-old Thoroughbred mare was evaluated because of placental abnormalities and a retained placental remnant. Results: Microbial culture of the placenta yielded pure growth of Amycolatopsis spp. Histologic examination of the placenta revealed a focally expanding chorionitis with intralesional gram-positive filamentous bacilli and multifocal allantoic adenomatous hyperplasia on the apposing allantoic surface. Results: Treatment with lavage and oxytocin resulted in expulsion of the placental remnant within hours of parturition. The mare did not become pregnant again despite multiple breeding...
Leeth C, Adkins J, Hay A, Bogers S, Potter A, Witonsky S, Zhu J.Immunological studies in the horse are frequently hampered by lack of environmental control, complicated study design, and ethical concerns when performing high risk studies. The purpose of the current study was to investigate the utility of a xenograft model for studying acute equine immune responses. Immunocompromised non obese diabetic (NOD). sudden combined immunodeficiency (scid).gamma-/- (NSG) mice were engrafted with either equine peripheral blood lymphocytes (PBLs) or equine bone marrow to determine an optimal protocol for equine lymphocyte engraftment. We found that both PBL and bone ...
Fernie DS, Cayzer I, Chalmers SR.A passive haemagglutination test (PHT) which has been developed for the detection of antibodies to the contagious equine metritis organism (CEMO) in serum is described. Samples from each of 30 mares with metritis were positive with titres in the range 256 to 4096. Samples from each of 239 clinically normal mares and 30 colts and fillies believed not to have been exposed to CEMO were negative with titres of less than 256, the majority of samples (97 per cent) showing a titre of 32 or less.
Fayer R, Dubey JP.Eight ponies and a horse were inoculated orally with sporocysts of Sarcocystis fayeri from dogs. They were examined for clinical signs of infection and killed 10, 15, 20, 25, 30, 50 (horse), 77, 101, and 156 days after inoculation (DAI). Elevated temperature was observed in three ponies 20 and 26 DAI and anemia was observed in three ponies and the horse 15 to 69 DAI. Schizonts were found in or near cells lining capillaries or arteries of the heart, brain, and kidney 10, 20, and 25 DAI. Immature cysts containing only metrocytes were first found in muscles 50 DAI. Mature intramuscular cysts cont...
Van Rensburg IB, Collett MG, Ronen N, Gerdes T.An adult stallion presented with a severe papular dermatitis of especially the neck, chest and genitalia. A marked scrotal oedema was present. Histopathological examination of skin biopsies, revealed the presence of numerous intracytoplasmic molluscum bodies in areas of focal epidermal hyperplasia. Electron microscopical examination showed the presence of typical pox virions in affected epidermal cells. Attempts at viral isolation were unsuccessful. This is believed to be the first reported case of molluscum contagiosum in a horse in the Republic of South Africa.
Rose PL, Bradley WM.Strangulating volvulus of the large colon was treated by resection and anastomosis of the colon in 9 horses. Tissue specimens were obtained at the site of the resection for histologic evaluation. An attempt was made to correlate the appearance of the colon at the time of surgery to the histologic evaluation and the eventual outcome. Six of the 9 horses (66%) survived. This is in contrast to a reported survival of 34.7 to 36% after decompression and reduction of colonic volvulus. Survival after surgery could not be predicted on the basis of visual assessment or histologic examination.
Dyson S.The results of a detailed investigation of 58 horses with suspected shoulder lameness are described. Lameness was found to originate distal to the shoulder region in 22 horses. No diagnosis was reached in five horses. Genuine shoulder problems occurred in 29 horses. The clinical signs of shoulder lameness are described and contrasted with lower limb lameness. The limitations of currently available diagnostic techniques are discussed. Problems identified in the shoulder region included osteochondritis dissecans, subchondral bone cysts, arthrosis, fracture, luxation, septic arthritis and soft ti...
Rash A.During the summer months, there will be increased movement and, therefore, increased mixing of the horse population, leading to a higher risk of disease transmission and subsequent clinical cases. It is important that both vets and owners remain vigilant for equine influenza infection. Here, Adam Rash, of the Animal Health Trust, discusses the diagnosis of this disease.
Zouiten H, Berrag B, Oukessou M, Sadak A, Cabaret J.Sport and leisure horses in Morocco are treated with several anthelmintics, organophosphates (dichlorvos), benzimidazoles (mostly thiabendazole) or tetrahydropyrimidines (mostly pyrantel pamoate) against nematodes. We studied three horse stables in Rabat, one in Meknes and one in Bouznika. Two of the Rabat and Bouznika stables had introduced a large number of horses from countries (Argentina or Europe) where resistance to benzimidazoles is frequent, whereas the Meknes stud farm remained without foreign introduction. The number of treatments was not very frequent (twice a year in adult horses) ...
Borgsteede FH, Dvojnos GM, Kharchenko VA.The efficacy of treatment with cambendazole was tested in 1-year-old horses on a farm in Dubrovka, Ukraine. Thirty-five horses were treated. Their egg output was compared on the day of treatment and 14 days later with that of 33 untreated horses. Before treatment the mean number of eggs g-1 faeces was 614 in the controls and 766 in horses that had been treated. After 14 days the mean egg output in the controls was 580 and in the treated horses 369. This means a reduction of 54.5%. Only cyathostome larvae could be cultured from faeces collected after treatment. It can be concluded that benzimid...