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.
McIlwraith CW, Foerner JJ, Davis DM.The technique and results of arthroscopic surgery for the treatment of osteochondritis dissecans in 318 tarsocrural joints in 225 horses are reported. Of the 225 horses, 154 were racehorses or intended for racing. Arthroscopic surgery was an effective technique for treating osteochondritis dissecans of the tarsocrural joint. The overall functional ability and cosmetic appearance of the limbs were excellent. Post surgical follow-up information was obtained for 183 horses, of which 140 (76.5 per cent) raced successfully or performed their intended use following surgery. Of the remaining 43, 11 w...
Darien BJ, Potempa J, Moore JN, Travis J.Antithrombin-III (AT-III) activity was measured at the time of admission in 46 horses referred with colic. Differences in AT-III activities between animals treated medically or surgically and survivors or non-survivors were compared. The mean AT-III values for the horses treated medically (76.2 per cent), surgical survivors (69.5 per cent) and surgical non-survivors (55.9 per cent) were significantly different from the reference value for healthy adults (92 to 108 per cent). The mean AT-III activity of the survivors was significantly (P less than 0.01) greater than that of the nonsurvivors. Th...
Hackett RP, Ducharme NG, Fubini SL, Erb HN.Videorecordings of the laryngeal activity of 108 unsedated horses were obtained at rest by passing a flexible videoendoscope into the nasopharynx through the right ventral meatus. All videotaped images were reviewed once, and 72 were reviewed twice, by three veterinarians. Laryngeal cartilage movement was assessed subjectively with a five-tier grading system. The mean intraobserver agreement was 83.3% (range, 75.0%-90.2%) with a kappa statistic of .65 to .98. The mean interobserver agreement was 79.0% (range, 70.4%-80.6%) with a kappa statistic of .51 to .90. A computer program was developed t...
Blunden AS, Mackintosh ME.A series of 31 thoroughbreds and 18 non-thoroughbreds was examined post mortem to assess what bacteria might be present in the lower respiratory tract, and to assess their significance by correlating the bacteriological findings with histological changes in the lung. The distal trachea and seven representative lung sites were swabbed in each case. Sixty-six per cent of the sites were sterile with remaining sites producing scanty growths of mainly coagulase negative Staphylococcus spp., E. coli, Bacillus spp. and Pseudomonas spp. Anaerobes, mainly Clostridium perfringens, Bacteroides fragilis a...
Hall LW, Aziz HA, Groenendyk J, Keates H, Rex MA.To investigate activity in respiratory muscles, insulated wire electrodes were used to record electromyographic activity in the costal diaphragm and in the intercostal, serratus ventralis, internal abdominal oblique, transversalis and rectus abdominis muscles in conscious horses and in the same animals when anaesthetised. Electromyographic activity was related to respiratory phases as recorded by a stethograph around the chest wall. The costal diaphragm showed tonic and inspiratory activity in both conscious and anaesthetised animals. The principal muscle actively involved in expiration was th...
Paradis MR, Breeze RG, Bayly WM, Counts DF, Laegreid WW.The hematologic and pathologic effects of orally administered L-tryptophan and indoleactic acid and of L-tryptophan administered IV were studied in ponies. Sixteen adult Shetland ponies were allotted into 4 experimental groups. Group 1 consisted of 5 ponies (1-5) given 0.6 g of tryptophan/kg of body weight in a water slurry via stomach tube. Group 2 included 4 ponies (6-9) given 0.35 g of tryptophan/kg orally. Group-3 ponies (10-13) were given 0.35 g of indoleacetic acid/kg orally. Group 4 consisted of 3 ponies (14-16) given a single 4-hour IV infusion of 0.1 g of tryptophan/kg. Restlessness, ...
Ricketts SW, Alonso S.The results of a retrospective analysis of 3,804 endometrial biopsy specimens collected from non-pregnant mares during the course of routine equine stud farm practice demonstrates a significant and practically useful correlation between the severity of chronic degenerative endometrial disease (CDE) diagnosed and age of mare at the time of examination. There were significant correlations between the number of foals born and the mares' barren years prior to biopsy and the severity of CDE, but the differences were not sufficiently large to be useful. Correlations between the severity of chronic i...
Edington N, Smyth B, Griffiths L.One of three mares in the last trimester of pregnancy became paraplegic 7 days after experimental infection with EHV-1 and was killed 10 days after infection (d.p.i.). The other two mares aborted foetuses at 12 and 14 d.p.i. In the first mare, virus was detected by immunofluorescence (IIF) and immunoperoxidase (IP) staining in endothelial cells of the endometrium, placenta and umbilical vein, but not in any other foetal tissues. In the experimentally aborted foetuses, and in two other independent field cases of abortions, endothelial cell infection was also detected in the foetuses, both in ma...
Miksík I, Deyl Z.Skin and aorta collagen specimens of Wistar rats, white mice, beagle dogs, cats, horses, and human necropsies of different ages were examined with respect to the content of glycated products. The data presented show that (a) glycation and accumulation of the chromophore(s) are comparable in collagen samples from different species of comparable age; (b) glycation and pigmented accumulation increase markedly during the first 5-10 years of age; (c) the extent of glycation is different in different tissues (in particular, glycation of aortal collagen is about twice that of skin collagen); and (d) ...
Wagner AE, Muir WW, Hinchcliff KW.The cardiovascular effects of xylazine and detomidine in horses were studied. Six horses were given each of the following 5 treatments, at 1-week intervals: xylazine, 1.1 mg/kg, IV; xylazine, 2.2 mg/kg, IM; detomidine, 0.01 mg/kg, IV; detomidine, 0.02 mg/kg, IV; and detomidine, 0.04 mg/kg, IM. All treatments resulted in significantly decreased heart rate, increased incidence of atrioventricular block, and decreased cardiac output and cardiac index; cardiac output and cardiac index were lowest following IV administration of 0.02 mg of detomidine/kg. Mean arterial pressure was significantly redu...
Madison JB, Sommer M, Spencer PA.A retrospective evaluation of 64 cases of suspected infectious arthritis in horses was undertaken to determine the relations among histopathologic findings in synovial membrane specimens, cytologic findings in synovial fluid samples, and bacterial culture results. Positive cultures were obtained from 55% of the joints, and 18 different bacterial organisms were cultured. Culturing of synovial fluid yielded bacterial growth more often than did culturing of synovial membrane. Histologic evaluation (H&E and Gram stain) of synovial membrane specimens provided little information to help distingu...
Whitwell KE.An autopsy study of one dead and two sick hares from an East Anglian estate on which two mares had died of grass sickness revealed that two of the hares were suffering from a polyganglionopathy and alimentary tract changes, remarkably similar to those seen in grass sickness in horses. No such abnormalities were found in two healthy hares from the same locality.
Baird AN, Cohen ND, Taylor TS, Watkins JP, Schumacher J.During a 5-year period, renosplenic entrapment of the large colon was diagnosed in 57 horses referred to the Texas Veterinary Medical Center. The signalment of and clinical signs of disease in these horses were compared with such variables in 200 horses referred for other types of colic. Findings did not support a male gender predilection for this disease, as was previously reported. The case survival rate was 93% for this group of horses. Fourteen of the horses were treated nonsurgically by rolling them clockwise while they were under general anesthesia. Data supported the safety and efficacy...
Dumasia MC, Houghton E.A method for the screening and confirmatory analysis of beta-agonists and -antagonists in equine urine is described. Following initial enzymic hydrolysis, the basic drugs and metabolites are extracted using Clean Screen DAU or Bond Elut Certify cartridges, and analysed as their trimethylsilyl ether or 2-(dimethyl) silamorpholine derivatives by capillary gas chromatography-mass spectrometry. The method proved to be very sensitive and selective for basic drugs. After administration of therapeutic doses of propranolol, metoprolol, timolol, isoxsuprine and clenbuterol to thoroughbred horses, the p...
Donahue JM, Smith BJ, Redmon KJ, Donahue JK.A study was conducted to evaluate a recently available fluorescent antibody test (FAT) conjugate for the detection of leptospires in tissues of aborted and stillborn horses, to determine the leptospira antibody titers and compare serologic test results with FAT results, and to determine the prevalence of leptospira-induced abortions and stillbirths in the equine population of central Kentucky. From July 1, 1988 through June 30, 1989, 15 (2.5%) of 594 submissions (fetuses, stillborn foals, and/or placentas) were diagnosed as leptospirosis by the FAT (14 of 15 tested) and/or microscopic agglutin...
Greiner EC, Mays MB, Smart GC, Weisbrode SE.Verminous mastitis was the reason for euthanasia of a 22-yr-old Paso Fino mare from Miami, Florida. The etiologic agent was a species of Cephalobus (Rhabditida: Cephalobidae), a genus of soil-inhabiting nematodes that were obviously multiplying in the mammary gland. Only females and larvae were detected in the tissues by histologic section or by teasing the tissue to liberate the worms. At least 12,900 individuals were present per gram of tissue. This is the first case of Cephalobus infecting horses and it indicates that not all histiotropic infections of horses by rhabditoid nematodes are by ...
Reed SM, Robertson JT.This article reviews recent diagnostic procedures that have arisen over the last 10 years. Videoendoscopy of horses on a high-speed treadmill allows observation of some of the changes that take place in a horse's airway during exercise. Measurements of upper airway airflows and transupper airway pressure, the use of an esophageal balloon and a Ventigraph to measure changes in pleural pressure, and pulmonary function testing are new techniques that aid the researcher in understanding the mechanics and pathologic characteristics of airway diseases and help the practitioner in assessing the sever...
Hinchcliff KW, Byrne BA.Aspects of a detailed examination of the respiratory system of the horse with suspected respiratory system disease are described. This review includes discussions of the terminology of signs associated with respiratory system disease; radiographic examination of the upper and lower airways and thorax; nuclear scintigraphy; percutaneous and endoscopic tracheal aspiration; bronchoalveolar lavage; electromyography; blood gas analysis; and pleuroscopy and pleural fluid examination.
Traub-Dargatz JL.Bacterial pneumonia in the horse often occurs secondary to viral respiratory infection; however, primary infections can occur. A diagnosis of bacterial pneumonia is made on the basis of history, physical examination, and laboratory and radiographic findings. Treatment consists of appropriate antimicrobial therapy for at least 7 to 10 days; further therapy may be needed in more severe cases. Prevention of bacterial pneumonia includes attempting to prevent viral respiratory infections and appropriate management to prevent stress to the respiratory tract.
Bocklisch H, Ludwig C, Lange S.Between 1982 and 1989 59 equine fetuses were investigated for chlamydiae using animal experiments and embryonated eggs. Chlamydiae were isolated from 16 fetuses (27.1%) originating from 8 studs. The macroscopical lesions of the fetal organs were characterized by extensive haemorrhages. The histological picture shows severe lesions of the blood vessels of different organs. In 6 studs in which chlamydiae had been isolated, blood sera of clinically healthy and pregnant mares were investigated for antibodies during 1989 and 1990. Antibody titres between 1:10++ and 1:40 were detected by using compl...
Watrous BJ, Hultgren BD, Wagner PC.Thirty-six of 50 young equids examined at necropsy for gross pathologic and histopathologic evidence of osteochondrosis were determined to have lesions characteristic of this disorder in the distal joints of the tarsus. Abnormalities ranged from retained endochondral cores underlying undisturbed articular cartilage surfaces to clefts, subchondral osseous cyst-like lesions, and cartilage ulceration. Our findings supported the conclusion that osteochondrosis may cause spavin in the juvenile equid.
Judson R, Songer JG.The minimal inhibitory concentrations of 39 antimicrobial agents for 54 isolates of Corynebacterium pseudotuberculosis in vitro have been determined. The most active agents were penicillins, macrolides, tetracyclines, cephalosporins, lincomycin, chloramphenicol, and rifampicin. Most isolates were resistant to aminoglycosides, nitrofurans, polymyxins, nalidixic acid, and cycloheximide.
Schuberth HJ, Hadam M, Leibold W.The determination of differentiation and transplantation antigens will be of growing importance in immune diagnosis for individual animals as well as for breeding purposes in populations. Differentiation antigens characterize subsets of cell populations and indicate their functional capacity while transplantation antigens represent markers of individuals of a species. Occurrence and significance of these antigenic systems are briefly reviewed.
Staempfli HR, Townsend HG, Prescott JF.Clinical and hematological changes observed on presentation of 47 horses referred to the Ontario Veterinary College with acute idiopathic colitis were analyzed for their prognostic features. Cases of acute enterocolitis were characterized by fever, dehydration, abnormalities of serum electrolyte concentrations, azotemia, hypoalbuminemia, and increased serum concentrations of muscle enzymes. Severely dehydrated horses were seven times more likely to die or be euthanized than those that were not dehydrated. Other factors associated with failure to survive included the following: increased hemato...
Bello TR.A controlled test was done in 30 naturally infected ponies to evaluate the antiparasitic activity of the dienbendazole analog VET 220-S given alone or with trichlorfon (TCF) by nasogastric intubation. Six ponies were nontreated; 6 were given VET 220-S (5.0 mg/kg); 6 were given TCF (40 mg/kg); 6 were given VET 220-S (2.5 mg/kg) and TCF (40 mg/kg); and 6 were given VET 220-S (5.0 mg/kg) and TCF (40 mg/kg). All ponies were euthanatized and necropsied 7 or 8 days after treatment. Draschia megastoma, Oxyuris equi, Strongylus vulgaris, S edentatus, and small strongyles were removed efficaciously by ...
Silvia PJ, Fitzgerald BP.An attenuated ovulatory rise in circulating concentrations of LH is characteristically associated with the first seasonal reproductive cycle of horse mares. Unlike ovulations (OV) of subsequent estrous cycles, the first OV of the breeding season (OV1) is not preceded by elevated concentrations of progesterone (PROG). Hence, the ability of pretreatment with PROG to abolish attenuation of LH-secretion associated with OV1 was investigated. Ten nonpregnant anestrous mares were randomly divided into 2 groups; control (C) and treated (T). Per individual, when diameter of the largest follicle was con...
Knospe C, Budras KD.To answer the many open questions concerning the development of the horse's ovary, first the prenatal development was investigated. It resulted that follicles derive from the germinal epithelium and its cords, whereas the Leydig cells and the rete blastema originate from the mesonephros. In the second third of pregnancy the Leydig cells undergo an enormous proliferation, in the last third they degenerate. However this degeneration is not connected with the postnatal development of the ovulation groove.
Thompson DL, Voelkel SA, Reville-Moroz SI, Godke RA, Derrick DJ.Effects of testosterone propionate (TP) treatment on plasma concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) before and after an injection of gonadotropin releasing hormone (GnRH) were studied using ovariectomized cows and pony mares. An initial injection of GnRH (1 microgram/kg of body weight) was followed by either TP treatment or control injections for 10 (cows) or 11 (ponies) d. A second GnRH injection was administered 1 d after the last TP or oil injection. Concentrations of LH and FSH were determined in samples of plasma taken before and after each GnRH i...
Brown CM, Holmes JR.The paper describes observations on 8 horses at rest using catheter-mounted microtransducers to record intracavity pressures. In 5 of them records were obtained from both left and right sides and in 3 horses from the right heart only. Twelve indices were measured. Variations in left ventricular end-diastolic pressure seemed to influence the results on many of the parameters. It is suggested that left ventricular end-diastolic pressure itself may be a useful guide to left ventricular functional efficiency but more work is necessary to further evaluate these indices as possible measures of myoca...
GARDIKAS C, KALLINIKOU M, KALLINIKOS G.The present experiments seem to indicate that horse blood is deficient in both Factors VIII and IX, the concentration of Factor VIII varying from 30 to 60 per cent of the normal human levels, and the concentration of Factor IX varying from 50 to 80 per cent, the corresponding concentrations in 12 normal human males varying from 60 to 150 per cent and from 70 to 150 per cent, respectively.
The finding that the recalcification time of horse plasma was considerably longer than that of normal human plasma is of interest, since it is known that only very low concentrations of Factor VIII or Fact...