Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Lavoie JP, Pascoe JR, Kurpershoek CJ.We studied the temporal changes in respiratory mechanics associated with xylazine administration (1.1 mg/kg of body weight, IV) in standing horses (experiment 1), and determined the effects of head and neck position (experiment 2) and atropine administration (experiment 3) on the observed changes. Thoroughbred geldings, 3 to 5 years old (5 in experiment 1, 4 in experiments 2 and 3) were used. Flow rates were obtained from a pneumotachograph and a differential transducer attached to a tight-fitting mask. Electronic integration of the flow signal gave tidal volume. Total pulmonary pressure (PL) ...
Murphy TW, McCollum WH, Timoney PJ, Klingeborn BW, Hyllseth B, Golnik W, Erasmus B.Equine arteritis virus (EAV), a non-arthropod borne togavirus, has been shown to have a global distribution. To date, no major antigenic variation has been demonstrated between EAV isolates from different geographic origins. In this study, the genomic RNA of EAV isolates obtained from horses of different breeds in various countries around the world was oligonucleotide fingerprinted. Comparisons of these fingerprints were used to determine the extent of genomic variation among such isolates. Comparisons among isolates from North American horses revealed, for the most part, oligonucleotide homol...
Ensink JM, Klein WR, Mevius DJ, Klarenbeek A, Vulto AG.The pharmacokinetics of ampicillin and amoxicillin following intravenous administration at a dose rate of 15 and 10 mg/kg respectively were studied in four healthy adult horses. Pharmacokinetics of pivampicillin and amoxicillin were studied after oral administration to four healthy adult horses. Pivampicillin, a prodrug of ampicillin, was administered orally to starved and fed horses at a dose rate of 19.9 mg/kg, which is equivalent on a molecular basis to 15 mg/kg ampicillin. Amoxicillin was administered orally to starved horses only, at a dose rate of 20 mg/kg. Ampicillin and amoxicillin con...
Rossdale PD, McGladdery AJ, Ousey JC, Holdstock N, Grainger L, Houghton E.Maternal plasma progestagen concentrations increase about 20 days before parturition. The major contributors to the increase are reduced metabolites (ie 5 alpha-pregnanes). Precocious increases (ie less than 310 days of gestation) in these metabolites may occur in abnormal pregnancies. The effects of CRH, ACTH or betamethasone administered to the foetus at gestational ages ranging from about 250 to 320 days were examined. Sixteen healthy pony mares were used for foetal injection employing aseptic techniques. Water or normal saline were used as controls. Maternal plasma progestagen concentratio...
Crabb BS, Nagesha HS, Studdert MJ.Equine herpesvirus 4 (EHV4) glycoproteins of M(r) 63K and 250K were identified in the supernatant of infected cell cultures. The 63K glycoprotein was type-specific; that is, it reacted with monospecific sera from horses that had been immunized or infected with EHV4, but not with monospecific sera from horses immunized or infected with EHV1, a closely related alphaherpesvirus. It was postulated that the secreted protein may be the homologue of similarly secreted glycoproteins of herpes simplex virus 2 glycoprotein G (HSV2 gG) and pseudorabies virus (PRV) gX, which is the homologue of HSV2 gG. T...
Chaffin MK, Schmitz DG, Brumbaugh GW, Hall DG.Splenic and hepatic ultrasonography were beneficial for diagnosis of lymphosarcoma in 3 horses with anorexia, weight loss, and lethargy. Ultrasonographic abnormalities of the spleen included a large, complex, hypoechoic mass in 1 horse, multiple well-marginated, hypoechoic nodules in 1 horse, and diffuse hyperechogenicity in another horse. Ultrasonographic abnormalities of the liver included a spherical, hypoechoic nodule in 1 horse and diffuse hyperechogenicity in another. Histologic examination of ultrasound-guided biopsy specimens or aspirates revealed lymphosarcoma. Necropsy findings confi...
Naylor JM, Clark EG, Clayton HM.We examined 18 horses with clinical signs of chronic obstructive pulmonary disease (COPD) using physical examination, cytological and bacteriological evaluation of bronchoalveolar fluid, and percutaneous lung biopsy. In 16 cases, histological examination of lung tissue confirmed the diagnosis of COPD. Two horses were excluded: one had uncomplicated bacterial pneumonia and in the other a satisfactory lung biopsy could not be obtained. In horses with COPD, the most common historical complaint was coughing, which was reported in 88%. The most frequently detected abnormal finding on physical exami...
Hashimoto Y, Reese S, Bragulla H, Budras KD.Carbohydrate moieties of cell membranes in the epidermis of equine skin and hoof were investigated using lectin-histochemistry. The loss of desmosomes during keratinization leads to a reduced lectin affinity. Lectin binding capacity of the intercellular matrix in the stratum corneum of the epidermis is weak compared to that of the intercellular kitt of the hoof. Qualitative differences in lectin binding of the intercellular kitt of different hoof segments correlate with the quality of the horn in the respective areas.
Mutoh K, Watanabe S, Wakuri H.The glands of pelvis renalis in adult and fetal horses were examined by histochemically. The glandular terminal was divided into two types, intraepithelial gland (IE) and extraepithelial gland (EE) by their locations and histochemical characters. Both glands were composed of mucous cells. The former lay in the transitional epithelium and were stained reddish with galactose oxidase-Schiff (GOS) and mild oxidation-Schiff (MOS), bluish purple with periodic acid-cold thionine Schiff-NaOH-PAS (PCP). The latter distributed in the lamina propria, but was not discovered in the fetus. They were stained...
Chaffin MK, Fuenteabla IC, Schumacher J, Welch RD, Edwards JF.The medical records of 11 horses with idiopathic muscular hypertrophy (MH) of the small intestine were reviewed to determine the clinical and pathological features of the disease. The median age of affected horses was 10.0 years (range 5-18 years). No breed or sex predisposition was apparent. Ten horses (91%) had chronic (23 days to 2.4 years) signs of mild, intermittent colic, and 1 horse had signs of severe colic of only 3 days' duration. Partial anorexia and chronic weight loss of variable duration (1-6 months) were prominent historical findings in 5 (45%) horses. Diagnostic tests, with the...
Soma LR, Uboh CE, Rudy J, Fegely J.The effects of the intravenous (i.v.) administration of 1.1 mg/kg of flunixin meglumine on thromboxane B2 (TxB2) concentrations were studied in sedentary and 2-year-old horses in training. The baseline TxB2 serum concentrations generated during clotting were 2.89 +/- 0.81, 2.19 +/- 0.25 and 0.88 +/- 0.12 ng/ml for the 2-year-old Thoroughbreds in training, sedentary horses under 10 and over 10 years old, respectively. There was a significant difference in baseline TxB2 concentrations between older and younger horses (P less than 0.005). Significant reduction in TxB2 production from baseline wer...
Chen CL, Sailor JA, Collier J, Wiegand J.Seven mature thoroughbred horses, weighing between 400 and 541 kg, were each injected intra-articularly into three joints with 6 mg/joint of triamcinolone acetonide (Vetalog). The fourth joint, the control, was injected with saline. Synovial fluid was taken from all four legs of the horses on days 1, 2, 3, 4, 5, 6, 7, 8, 11, and 15 following the injections. Triamcinolone acetonide was assayed by a radioimmunoassay. Blood was collected at 1, 2, 4, 6, 12 h and on days 1, 2, 3, 4, 5, 6, 7, 8, 11, and 15 following injection of either triamcinolone or saline. Both cortisol and triamcinolone were as...
Laverty S, Pascoe JR, Williams JW, Funk KA.A 10-year-old Appaloosa stallion was referred for evaluation of colic. At admission, the heart rate, capillary refill time, respiratory rate, and rectal temperature were high. Fifteen liters of reflux was obtained by nasogastric intubation. Palpation of an abdominal mass per rectum elicited signs of pain. At exploratory laparotomy, a mass was palpated in the ascending portion of the duodenum. The small intestine ruptured at the site of obstruction during manipulation. The horse was euthanatized. A large cholelith was the cause of the duodenal obstruction. At necropsy, multiple choleliths of va...
Geiser DR, Rohrbach BW.End-tidal carbon dioxide tension (PetCO2) and arterial carbon dioxide tension (PaCO2) were determined and compared in isoflurane-anesthetized spontaneously breathing equine neonates. End-tidal carbon dioxide and PaCO2 values increased with respect to time. Difference between values of PetCO2 and PaCO2 increased over time. End-tidal carbon dioxide tension was useful to predict changes in and was more closely correlated with PaCO2 early in the anesthetic period (T less than or equal to 60 minutes). The dead space volume to tidal volume (Vd/Vt) ratio increased with respect to time, indicating inc...
Hooper RN, Taylor TS, Behrens EA, Varner DD.Ovariohysterectomy was performed in 20 mares at three stages of estrus. An ecraseur was used to severe the ovarian branch of the ovarian artery and vein and the ovarian suspensory ligament en masse. All other vessels supplying the ovaries and uterus were doubly ligated and transected. All mares survived. Complications were intraoperative hemorrhage in three mares, postoperative vaginal bleeding in two mares, and a hematoma in the remnant of the broad ligament in one mare. No adhesions between the uterine stump or remnants of the broad ligament and abdominal structures were detected by palpatio...
Gulevskiĭ AK, Grishchenko VI, Tereshchenko OS, Zagnoĭko VI, Akhremenko AK, Kucherenko SN.The effect of the fraction (1-10 kDa) obtained from the brain of cold-adapted animal (Yakut horse) on Ca2+ transport in sarcolemma vesicles of cardiomyocytes was investigated. It was shown that during insertion of Yakut horse brain fraction into incubation medium at the concentration from 10(-9) M to 3.10(-5) M at Ca2+ transport substrate concentration from 0.1 mM to 1.0 mM, the rate of Ca2+ passive penetration into vesicles slightly increased and at Ca2+ transport substrate concentration 3 mM, which is physiologic, a decrease of rate values was established for all concentrations of the fracti...
Olsen SC, Coyne CP, Lowe BS, Pelletier N, Raub EM, Erickson HH.Furosemide, which commonly is used as a prophylactic treatment for exercise-induced pulmonary hemorrhage in horses, may mediate hemodynamic changes during exercise by altering prostaglandin metabolism. To determine if furosemide's hemodynamic effects during exercise in horses could be reversed, cyclooxygenase inhibitors were administered with furosemide. Four treatments were administered 4 hours prior to treadmill exercise at 9 and 13 m/s. They included a control treatment (10 ml of 0.9% NaCl solution, IV), furosemide (1 mg/kg of body weight, IV) administered alone, and furosemide in combinati...
Hanie EA, Sullins KE, Powers BE, Nelson PR.In 6 horses, bilateral metacarpal vertical series of three 4.0-mm unicortical drill holes were made. At random, one of each series of 3 holes was filled using a sternal 4.0-mm cancellous bone cylinder or a slurry of cancellous bone injected into the hole or left as an empty control. All horses had lateral metacarpal xeroradiographs at monthly intervals. Three horses (6 metacarpi) were examined post mortem after 4 months and 3 others after 6 months. Immediate through 4-month post-operative xeroradiographs demonstrated increased density in the holes with cancellous cylinders and no difference co...
Whithair KJ, Bowersock TL, Blevins WE, Fessler JF, White MR, Van Sickle DC.Septic arthritis was induced in one antebrachiocarpal joint of seven horses by the intra-articular injection of 1 mL Staphylococcus aureus suspension containing a mean of 10(5) colony-forming units. Twenty-four hours after inoculation, four horses were treated by regional perfusion with 1 g of gentamicin sulfate, and three horses received 2.2 mg/kg gentamicin sulfate intravenously (IV) every 6 hours. Synovial fluid was collected for culture and cytology at regular intervals, and the synovial membranes were collected for culture and histologic examination at euthanasia 24 hours after the first ...
Silvia PJ, Johnson L, Fitzgerald BP.In mares, the amount of gonadotrophin-releasing hormone (GnRH) is low in the hypothalamus during seasonal anoestrus, but by early spring, concentrations of GnRH are high. The timing of this response was characterized more precisely by determining concentrations of GnRH in hypothalamic tissue collected immediately before and at various times after the winter solstice (22 December 1986). Ovaries, pituitary gland, hypothalamus and a blood sample were collected from six groups of mares (6-12 mares per group) at death, 1 week before day of the winter solstice and 1, 2, 3 and 12 weeks afterwards. No...
Palmer SE, McGill LD.Freshly harvested equine skin incised with an electrosurgical unit, a radiosurgical device, or a carbon dioxide (CO2) laser was examined by light microscopy to determine the extent of thermal injury caused by each instrument. There was no significant difference between the thermal injury caused by the electrosurgical unit in the pure-cut mode and the CO2 laser in the superpulse mode, or between the electrosurgical unit and the radiosurgical device in the fully filtered cut mode. However, thermal injury caused by the CO2 laser was significantly less than that caused by the radiosurgical device....
Huber MJ, Schmotzer WB, Riebold TW, Watrous BJ, Synder SP, Scott EA, von Matthiessen PC.Four autogenous osteochondral fragments removed from the lateral trochlear ridge of the talus were arthroscopically placed as loose bodies in a randomly selected middle carpal joint in each of 10 horses. The contralateral middle carpal joint, subjected to a sham procedure, served as control. Postoperative treatment was consistent with that for clinical arthroscopic patients. Lameness evaluation, radiographic examination, carpal circumference measurement, and synovial fluid analysis were performed before and at scheduled intervals after surgery. After a 2-month confinement, horses were subjecte...
Gray PR, Derksen FJ, Broadstone RV, Robinson NE, Peters-Golden M.Heaves is a respiratory disorder of horses and ponies characterized by bouts of acute airway obstruction and airway hyperresponsiveness. We measured prostaglandin E2 (PGE2) and 15-hydroxyeicosatetraenoic acid (15-HETE) production in vitro in tracheal epithelium obtained from six affected horses at the time of acute airway obstruction as compared with six matched control horses. Strips of epithelium and subepithelial tissue were prepared and stimulated with A23187, histamine, and bradykinin. The PGE2 and 15-HETE in media from strips was quantitated by radioimmunoassay. 15-HETE above the limits ...
Belknap JK, Nickels FA.Third-degree perineal lacerations or rectovestibular fistulae in 17 mares were repaired surgically by a one-stage method. Primary healing occurred in 14 mares; there were one complete dehiscence and two partial dehiscences with fistula formation. Twelve of 13 mares that were bred became pregnant; nine carried foals to term and two are still pregnant. Two mares have each produced one unthrifty foal. One mare repeatedly aborts in the first trimester. Four mares have produced several healthy foals with no further problems. One mare suffered further perineal trauma while foaling.
Coles GC, Bauer C, Borgsteede FH, Geerts S, Klei TR, Taylor MA, Waller PJ.Methods have been described to assist in the detection of anthelmintic resistance in strongylid nematodes of ruminants, horses and pigs. Two tests are recommended, an in vivo test, the faecal egg count reduction test for use in infected animals, and an in vitro test, the egg hatch test for detection of benzimidazole resistance in nematodes that hatch shortly after embryonation. Anaerobic storage for submission of faecal samples from the field for use in the in vitro test is of value and the procedure is described. The tests should enable comparable data to be obtained in surveys in all parts o...
O'Brien MA, Holmes MA, Duffus WP.Anti-tetanus toxoid (TT) antibody (Ig) levels in the supernatant of cultured, pre-immunised equine peripheral blood mononuclear cells (PBMC) were measured by an indirect enzyme-linked immunoabsorbent assay (ELISA). Optimal anti-TT Ig production occurred at concentrations of stimulating, purified TT of between 0.001 and 0.1 micrograms ml-1, which varied depending on the cell concentration. Optimal anti-TT Ig production was most consistently produced when the cell concentration was 5 x 10(6) ml-1. At this cell concentration maximal anti-TT Ig was induced using 0.1 micrograms ml-1 TT. At a cell c...
Holmes MA, Lunn DP.As part of a project to raise specific pathogen free (SPF) Welsh Mountain Pony foals, free from exposure to Equid herpesvirus type 1, foals were removed from their dams at birth and fed bovine colostrum. This study characterises the uptake of bovine colostral immunoglobulin and production of endogenous immunoglobulin, in 10 SPF foals. An enzyme-linked immunoadsorbent assay was developed to measure serum concentrations of bovine IgG1 (boIgG1) to assess the efficiency of transfer, and rate of elimination of boIgG1 by the foal. The endogenous production of equine IgG was studied using a single ra...
Pietra M, Cinotti S, Ducci A, Giunti M, Peli A.During an 18 day test, we measured the cytokine mRNA expression (Interleukin-1beta [IL-1beta], Interleukin-8 [IL-8], Interferon-gamma [IFN-gamma], Tumor Necrosis Factor-alpha [TNF-alpha]) of cells from bronchoalveolar lavage fluid [BALF] in five horses previously diagnosed with RAO, before and during challenge exposure, and after the desensitization phase which involved dexamethasone treatment and environmental modification. Simultaneously, the same cytokine mRNA expression of cells from BALF in four asymptomatic RAO-affected horses maintained outdoors was analyzed. An evident respiratory dist...
Kong N, Yi R, Zhao S, Sandhu J, Lam G, Loganathan D, Morrissey B.A sensitive hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry method was developed and validated for the simultaneous detection and quantification of etilefrine and oxilofrine in equine blood plasma and urine. The method is highly sensitive and specific with good precision and accuracy. In plasma the limit of detection and limit of quantification are 0.03 and 0.1 ng/mL, respectively, for both analytes. In urine the limit of detection and limit of quantification are 0.3 and 1 ng/mL, respectively, for both analytes. The suitability of the method for doping con...
Dirikolu L, Lehner AF, Harkins JD, Woods WE, Karpiesiuk W, Gates RS, Fisher M, Tobin T.Pyrilamine is an antihistamine used in human and veterinary medicine. As antihistamines produce central nervous system effects in horses, pyrilamine has the potential to affect the performance of racehorses. In the present study, O-desmethylpyrilamine (O-DMP) was observed to be the predominant equine urinary metabolite of pyrilamine. After intravenous (i.v.) administration of pyrilamine (300 mg/horse), serum pyrilamine concentrations declined from about 280 ng/mL at 5 min postdose to about 2.5 ng/mL at 8 h postdose. After oral administration of pyrilamine (300 mg/horse), serum concentrations p...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Non-specific hemolysis has often been observed during complement-fixation (CF) tests for equine herpesvirus type-1 (EHV-1), even when the sera have virus-specific CF antibodies. This phenomenon has also been reported in CF tests for various infectious diseases of swine. We found that the sera from 22 of 85 field horses (25.9%) showed non-specific hemolysis during conventional CF testing for EHV-1. Because pretreatment of swine sera with potassium periodate (KIO4) improves the CF test for swine influenza, we applied this method to horse sera. As we expected, horse sera treated with KIO4 did not...
Teti G, Mazzotti E, Gatta V, Chiarini F, Alfieri ML, Falconi M.Osteoarthritis (OA) is described as a chronic degenerative disease characterized by the loss of articular cartilage. Senescence is a natural cellular response to stressors. Beneficial in certain conditions, the accumulation of senescent cells has been implicated in the pathophysiology of many diseases associated with aging. Recently, it has been demonstrated that mesenchymal stem/stromal cells isolated from OA patients contain many senescent cells that inhibit cartilage regeneration. However, the link between cellular senescence in MSCs and OA progression is still debated. In this study, we ai...
Milne EM, Pemberton AD, McGorum BC, Dixon PM, Scudamore CL, Miller HR.The concentration of alpha-1 proteinase inhibitor (API) was measured in the pulmonary epithelial lining fluid (PELF) of horses with chronic obstructive pulmonary disease (COPD) while they had clinical signs and while they had none. The concentrations of total protein, albumin and API were significantly higher in the PELF of animals with clinical signs of COPD. The correlation between albumin and API in the PELF suggested that most of the API was derived from the serum.
Shimozawa K, Ueno Y, Ushiya S, Kusunose R.Medical and racing records of 155 Thoroughbred racehorses that underwent arthroscopic surgery for carpal chip fractures were investigated. Articular damage for 98.4% of the fractures was classified as G1 or G2 using McIlwraith's criteria. The rate of return to racing after surgery was 82.6%. Evaluation of racing performance after surgery was attempted using a placing index (PI) based on race finish position. There was no significant difference in the PI distribution between horses that underwent surgery and other healthy horses.
Glass KG, Arnold CE, Varner DD, Chaffin MK, Schumacher J.OBJECTIVE To describe the signalment, clinical features, and outcome for male horses with urethral rents following perineal urethrotomy (PU) or corpus spongiotomy (CS). DESIGN Retrospective case series. ANIMALS 33 horses. PROCEDURES Medical records of male horses examined because of hematuria or hemospermia caused by urethral rents that underwent PU or CS at a referral hospital between 1989 and 2013 were reviewed. Data regarding signalment, clinical features, urethroscopic findings, surgical treatment, and outcome were recorded. Long-term follow-up information was obtained by telephone intervi...
Savage KA, Colahan PT, Tebbett IR, Rice BL, Freshwater LL, Jackson CA.To determine the effects of a dose of caffeine (2.5 mg/kg, IV) administered to physically fit Thoroughbreds during incremental exercise testing to fatigue on a treadmill. Methods: 10 conditioned Thoroughbreds. Methods: Horses were randomly assigned to receive caffeine or a control solution. Each horse received both treatments in a crossover design with a 3-week interval between treatments. Each horse was administered caffeine (2.5 mg/kg) or an equivalent amount of a control solution IV. One hour after injection, each horse performed an incremental exercise test to exhaustion. Hematologic value...
Hanada M, Maeda Y, Oikawa MA.The secretions of the equine endometrial glands are essential for the survival, growth, and development of the conceptus in early pregnancy, and endometrial gland density is directly related to successful pregnancy outcome. Endometrial biopsy is routinely used to assess the reproductive potential of broodmares. Some previous studies have shown that equine endometrial glands are uniformly distributed throughout the uterus; however, other work has shown variation of the endometrial architecture between biopsy sites, suggesting that a single biopsy is not representative of the entire endometrium....
Díaz S, Kienast ME, Villegas-Castagnasso EE, Pena NL, Manganare MM, Posik D, Peral-García P, Giovambattista G.In order to detect switching and/or manipulation of samples, the owner of a stallion asked our lab to perform a DNA test on a positive doping urine sample. The objective was to compare the urine DNA profile versus blood and hair DNA profiles from the same stallion. At first, 10 microsatellite markers were investigated to determine the horse identity. No results were obtained when horse specific markers were typed in the urine sample. In order to confirm the species origin of this sample we analyzed the mitochondrial cytochrome b gene. This analysis from blood and hair samples produced reproduc...
Trachsel DS, Drozdzewska K, Bergmann F, Ziegler U, Gehlen H.West Nile virus (WNV) is a mosquito-borne viral pathogen of global importance and is considered to be the most widespread flavivirus. In Germany, first infections with WNV were detected in 2018 and it is expected for these to become more frequent in consequence to warmer winters followed by a rainy/humid springtime. WNV is maintained in an enzootic cycle between ornithophilic mosquitoes and certain wild bird species. Humans and horses are so-called "dead-end hosts" of a WNV infection. They frequently do not fall ill, however occasionally develop overt infections ranging from mild febrile sympt...
Preston SA, Brown MP, Trumble TN, Chmielewski TL, Zimmel DN, Hernandez JA.To determine the effects of various presale radiographic findings for Thoroughbreds sold at a yearling sale on 2-year-old racing performance of those horses. Methods: 397 Thoroughbreds. Methods: Cohort study. Methods: Thoroughbreds offered for sale at a Thoroughbred sales facility in Kentucky were selected via a randomization procedure. Effects of various presale radiographic findings on the following measures of 2-year-old racing performance were determined: having started a race and having placed (ie, finished in first, second, or third place) in a race at least once, total amount of money e...
Deichsel K, Aurich J, Parvizi N, Bruckmaier RM, Aurich C.The aim of the present study was to determine effects of lactation on basal LH and IGF-1 concentrations and on the LH response to a GnRH-analogue at different stages of the oestrous cycle in mares. A total of 17 cyclic Haflinger mares were included in the study. Experiments were performed on lactating mares in first postpartum oestrus, the subsequent early luteal phase, and second postpartum oestrus. Non-lactating mares were used in oestrus and early luteal phase. Blood samples were taken for 1 h at 15 min intervals. Mares were then injected with the GnRH-analogue buserelin (GnRHa; 5 microg i....
Labeda DP, Price NP, Kroppenstedt RM, Donahue JM, Williams NM, Sells SF.Two actinomycete strains, NRRL B-24165(T) and NRRL B-24166(T), isolated from lesions on equine placentas in Kentucky, USA, were analysed using a polyphasic taxonomic approach. On the basis of phylogenetic analysis of 16S rRNA gene sequences, morphological observations and the presence of ll-diaminopimelic acid as the diagnostic diamino acid in whole-cell hydrolysates, the new isolates clearly belonged to the genus Streptomyces. Analyses of the phylogenetic positions of strains NRRL B-24165(T) and NRRL B-24166(T) based on 16S rRNA gene sequences of all recognized species of the genus Streptomyc...
Osborne VE.Foaling figures for Thoroughbred mares in Australia show a puzzling disparity between conception and foaling rates in the second half of the 22 years of official data collection between 1950 and 1972. In the first 9 years of the survey, the live foal percentages rose in parallel with conception rates, but then a divergence of the figures occurred with the conception rate continuing to improve by 6-25% while the foaling rate improved by only 0-01% over the same period. An hypothesis supported by data from two studs is considered that stress factors additional to those experienced by mares in th...
Monreal L, Navarro M, Armengou L, José-Cunilleras E, Cesarini C, Segura D.To assess the effect of enteral fluid therapy (EFT) in horses with colic, 78 adult horses with colon impactions and 30 with left dorsal colon displacements received an isotonic electrolyte solution via a nasogastric tube at a rate of 8 to 10 l every two hours until resolution of clinical signs. Clinical progression was monitored closely, and plasma biochemistry was evaluated before, during and after treatment. Volume of fluids, time to resolution, and outcome were also recorded. EFT was well tolerated by 102 of 108 horses and was an effective method to resolve 99 per cent of colon impactions a...
Smith DF.The future of veterinary medicine is best understood in the context of history. What began as a profession rooted in urban centers in proximity to horses, physicians, and medical schools, was transformed into a land grant-based agricultural profession with the arrival of the internal combustion engine in the early twentieth century. Most of the United States' current veterinary colleges are still located in towns or small cities in the middle section of the country, outside the largest metropolitan areas where most veterinarians practice companion-animal medicine. Throughout veterinarian histo...
Freeman DE, Spencer PA.Age, breed, and gender distributions of 168 horses with umbilical hernia treated at the University of Pennsylvania School of Veterinary Medicine were analyzed to determine risk factors for this disease. For the 3 breeds that constituted the largest proportion of hospital and case populations, Thoroughbred, Standardbred, and Quarter Horse, the overall ratio of females to males was 1.63. In a hospital population of the same age group, 0 to 48 months, the female to male ratio was 0.93. Compared with males, females were at significantly higher risk for umbilical hernia after adjustment for breed a...
Mlodawska W, Okolski A.The effect of filly age on morphology of the ovaries, collected oocytes and their capacity for in vitro maturation (IVM) was examined. The ovaries of slaughtered fillies were classified into three groups, according to filly age: (I) <10 month old (<10MF); (II) approximately 1 year old (1YF); and (III) approximately 1.5 year old (1.5YF). The ovaries of mares were used as a control group. Ovarian morphology and collected oocytes were evaluated. Only oocytes with expanded (Ex) and compact (Cm) cumuli were used for IVM. In <10MF, 1YF, 1.5YF and mare groups, corpora lutea were found in the...
Yoshida T, Ohta Y.The experiment was conducted to estimate dietary threonine (Thr) requirement using plasma amino acid concentrations as a criterion in mature thoroughbreds. Four adult thoroughbreds were used, and a 4 × 4 Latin square design was used for four dietary Thr levels. Plasma Thr concentration was constant until 0.41%, and then increased rapidly with increasing dietary Thr levels. The Thr requirement was estimated to be 67% of lysine with plasma Thr concentration at four Thr levels.
Wesley IV, Schroeder-Tucker L.The genus Arcobacter encompasses campylobacter-like organisms that grow in air at 25 degrees C. Arcobacter has been detected or isolated from clinically healthy livestock as well as aborted fetuses and has been presumptively identified as either Campylobacter or Leptospira, based on its growth in selective semisolid media. Because reports from nonlivestock species are limited, this study examined nine presumptive isolates of Arcobacter spp. from an alpaca (Vicugna pacos), black rhinoceros (Diceros bicornis), white rhinoceros (Ceratotherium simum), gorilla (Troglodytes gorilla), gazelle (Eudorc...
Whitelock RG.This paper quantifies the extent of the radiation hazard to personnel from horses undergoing scintigraphy using technetium99m methylene diphosphonate (99Tcm-MDP). From the data produced it is possible to derive safe working protocols which are comfortably within the legislated limits for whole body doses as set out in the Ionising Radiations Regulations 1985. Measurements were made of the surface and environmental activities which result from individuals undergoing scintigraphic evaluation and also from urine contaminated bedding. The use of both high and low activities in the assessment of th...