In vivo studies involving horses refer to research conducted within living organisms to understand various biological processes, disease mechanisms, and therapeutic interventions in equine species. These studies provide insights into the physiological and pathological responses of horses under natural conditions. In vivo research encompasses a range of investigations, including pharmacokinetics, disease modeling, and the evaluation of treatment efficacy. It often involves the use of controlled environments to simulate real-life scenarios while observing the effects of specific variables on equine health. This page gathers peer-reviewed research articles and scholarly studies that explore the methodologies, findings, and implications of in vivo research in horses, contributing to the advancement of equine science and veterinary medicine.
Cooley PL, Milvae R, Riis RC, Laratta LJ.A study was performed to identify prostacyclin (PGI2) in equine aqueous humor, demonstrate an increase in PGI2 following anterior chamber paracentesis, and determine the effects of subconjunctival injection of flunixin meglumine on PGI2 accumulation. Twenty ponies were found to be normal upon ocular examination and were placed under general anesthesia. Anterior chamber paracentesis was performed in both eyes (right and left); immediately afterward, 25 mg of flunixin meglumine was injected (subconjunctivally) in the left eye. Aqueous paracentesis was performed 1.5 hours later (both eyes). Aqueo...
Pascoe RR.Twelve medicaments were tested for their efficacy in the treatment of Trichophyton equinum var. autotrophicum; povidone iodine, thiabendazole ointment, captan ointment and Burroughs Wellcome Ringworm Ointment gave satisfactory results but their usefulness may be limited for treatment of large numbers of horses. Aqueous washes containing 0.5% hexetidine or 0.3% chloramine-T did not prevent fungi being isolated from lesions for up to 7 days after treatment. Similarly neither etisazole nor thiabendazole suspension prevented fungi from being isolated from lesions for up to 15 days after treatment....
Spehar AM, Hill MR, Mayhew IG, Hendeles L.Pharmacokinetic characteristics of the anticonvulsant phenobarbital were studied in seven pony and two Thoroughbred foals aged between four and 10 days. A single, 20 mg/kg bodyweight (bwt) dose of phenobarbital was given intravenously over 25 mins and the serum concentrations of the drug were measured using an EMIT AED assay (coefficient of variation 1.37 per cent at 30 micrograms/ml, n = 7). Phenobarbital elimination was found to follow first order kinetics. The mean (+/- sd) peak phenobarbital serum concentration was 18.6 +/- 2.1 micrograms/ml at 1 h after initiation of infusion with a mean ...
Allen WR, Pashen RL.The blastomeres of 192- to 8-cell embryos recovered surgically 1-3 days after ovulation from 23 Pony mares were mechanically separated and inserted, in various combinations, into evacuated pig zonae pellucidae to make 27 'half' and 17 'quarter' micromanipulated embryos. These were embedded in agar and cultured in vivo in the ligated oviducts of ewes for 3.5-5 days to allow development to the late morula/early blastocyst stage. Subsequent surgical or non-surgical transfer of 13 'half' and 17 'quarter' embryos to mares resulted in 10 established pregnancies, including 2 monozygotic pairs. Surgic...
Strzemienski PJ, Benson CE, Acland HM, Kenney RM.Two groups of 3 mares were inoculated with Haemophilus equigenitalis or Pseudomonas aeruginosa on the 1st day of estrus. Uterine flushing samples were recovered on day 3 of estrus and day 8 after ovulation for each cycle. Mares were killed 22, 25, and 30 days after inoculation with P aeruginosa and 45, 46, and 49 days after inoculation with H equigenitalis. Pseudomonas aeruginosa was recovered from the uterus of 2 mares 48 hours after inoculation. Although the initial flushing sample of 1 of these 2 mares had an increased total protein concentration, there appeared to be little difference betw...
Higgins AJ, Lees P, Wright JA.In a series of experiments to examine equine inflammatory exudates for the presence of metabolites of arachidonic acid, including prostaglandin E2 (PGE2), a model for the induction and collection of exudates in ponies has been developed. Multiperforated polypropylene practice golf balls implanted subcutaneously in the mid-neck region were well tolerated and proved to be the most successful model. One such cage was implanted in the neck of each of seven ponies. Inflammatory exudates were induced by injecting 3.0 or 0.5 ml carrageenin into the cages and aspirates collected between three and 48 h...
Coignoul FL, Cheville NF.Six pregnant mares were given equine viral arteritis virus intravenously. Tissues from genital tracts, placentae, and fetuses were examined by light and electron microscopy to study the mechanism of abortion. Four mares which died with acute disease had diffuse vacuolation of endometrial epithelium and systemic necrotizing vasculitis. Two of these mares had dead fetuses and two had live fetuses; virus was isolated from tissues of one live fetus. Placentae of mares dying from acute disease did not have lesions attributable to infection; virus was isolated from two of these placentae. One of the...
Hartman W, Schamhardt HC, Lammertink JL, Badoux DM.Rosette strain gauges were bonded to the cranial, caudal, and medial surfaces of the tibia in the middiaphyseal region of 6 adult ponies. While the ponies were walking, the cranial side was mainly subjected to tension, and the caudal side, to compression. The compression strain on the caudal side was 1.5 times greater than the tension strain on the cranial side. None of these principal strains was aligned along the long axis of the bone; both deviated laterally from the long axis. On the medial surface, the principal strain deviated caudally about 40 degrees from the long axis. From analysis o...
Ribbeck R, Ilchmann G, Hiepe T.Research into the immunological diagnosis of gasterophilosis. So far there have been no reliable methods of diagnosing equine gasterophilosis intra vitam. Horses from the G.D.R. and the M.P.R. spontaneously infected with Gasterophilus spp. were tested for antibodies by the immunotechniques of counterimmunoelectrophoresis after Pesendorfer, passive haemagglutination and the intradermal test using antigen made from larvae of all 6 Gasterophilus spp. present in the palaearctis. All 3 techniques produced positive results. The intradermal injection produced an immediate reaction. A correlation betw...
Allhands RV, Torzilli PA, Kallfelz FA.The diffusion of glucose (180 M.W.), inulin (5,000 M.W.) and dextran (20,000 M.W.) into mature bovine and equine articular cartilage was studied. Concentration profiles were determined using a one-dimensional experimental configuration and the diffusion coefficient and partition coefficient calculated from a theoretical model. Glucose was found to diffuse the fastest, followed by inulin and dextran. The partition coefficient was similarly ordered. The rate of diffusion was found to decrease with increasing diffusion time, indicating a dependence on solute concentration. No time variation was e...
Ginther OJ.The equine embryonic vesicle has been shown to be highly mobile prior to day 15, moving from one horn to the other many times per day. In Experiment 1, intrauterine mobility patterns of the vesicle were compared between barren and postpartum mares on days 12, 13, or 14, using an ultrasound instrument. Location of the vesicle (left horn, right horn, body) was determined every five minutes during six two-hour trials in each group. Averaged over all trials, the vesicle moved from one horn to the other 1.1 times per two-hour trial. There were no significant differences between barren and postpartu...
Reville-Moroz SI, Thompson DL, Archbald LF, Olsen LM.The in vitro incorporation of [3H]leucine into immunoprecipitable follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was assessed for pituitaries from pony mares treated with testosterone propionate (TP) or oil (controls). Mares were treated every other day with TP (n = 4) at 350 micrograms/kg of body weight or with an equivalent volume of oil (n = 4). One day following the sixth injection of TP, each mare received an intravenous injection of gonadotropin releasing hormone (GnRH) at 1.0 micrograms/kg body weight and was bled frequently for 4 h. Treatment of mares with TP reduced F...
Erickson HH, Kitchell RL.In the last 2 decades there have been substantial advances in our knowledge of the scientific basis of the mechanisms of pain. Nociceptors or pain receptors are widespread in the skin and tissues of animals; chemical mediation of nociceptor excitation may provide a key for understanding the peripheral phenomena related to pain. The expression of pain in animals involves multiple ascending and descending branches, as well as specialized pain-signaling mechanisms in the spinal cord. The importance of these different pathways varies with species and circumstances. Endogenous neural systems in the...
Steckel RR, Page EH, Geddes LA, Van Vleet JF.The effect of low-level direct-current stimulation on skin wound healing in the horse was assessed. Self-sustaining electrical circuits with electrodes were implanted subcutaneously in or near the wound. Stimulation by direct current (10 or 20 microA) was used to determine the effect on equine skin healing. The efficacy of electrotherapy was evaluated by sequentially comparing the clinical appearance of the wound and measuring the size of the granulating wound bed. The histologic appearance of the healing stimulated wounds was compared with that in nonstimulated control wounds created on 9 hor...
Adams SB, Lamar CH, Masty J.Bipolar stainless steel electrodes were surgically implanted in 4 ponies to record myoelectrical and mechanical activity of the distal portion of the jejunum and pelvic flexure. After determining normal activity, the effects of neostigmine, xylazine, flunixin meglumine, dipyrone, panthenol, and atropine sulfate were determined. Flunixin meglumine, dipyrone, and panthenol had no effect on the motility of the jejunum or pelvic flexure. Xylazine and atropine sulfate decreased motility of the distal portion of the jejunum and pelvic flexure, with atropine sulfate having a greater effect and lastin...
Slusher SH, Freeman KP, Roszel JF.In a review of specimens from 80 mares with concurrently collected endometrial biopsy and cytology preparations, eosinophils were found in 33 specimens from 27 mares. In 22 of 27 mares, there were conditions predisposing to pneumovagina, which presumably led to pneumouterus. Thirty-two of the 80 mares also had conditions predisposing to pneumovagina but no eosinophils in the uterine specimens. Experimental introduction of air into the uterus of 3 mares resulted in eosinophils in their uterine specimens.
Kaneps AJ, Hultgren BD, Riebold TW, Shires GM.Surgical incisions were made in the skin and superficial digital flexor tendons in horses. A low intensity laser therapy device was used to treat the limbs. After laser therapy was completed, skin and superficial digital flexor tendons from incised laser-irradiated, incised-control, and nonincised-control limbs were compared microscopically. Qualitative differences between laser irradiated and nonirradiated tissues were not found. The laser therapy device used in this study may be of insufficient power to affect wound healing.
Nixon AJ, Stashak TS, Smith FW, Norrdin RW.Carbon fibre-polylactic acid composites and monofilament non-absorbable suture material were compared for the repair of surgically transected superficial digital flexor tendons in 10 horses. All surgical wounds healed by first intention. The repaired tendons were enlarged, the carbon implanted tendons being larger than those sutured. The horses were killed at six, eight, 12,20 or 24 weeks. Greater fibrous thickening occurred in tendons repaired with carbon fibre, especially at 12 weeks postoperatively. Carbon fibre incited a greater histological response with macrophages, lymphocytes, plasma c...
Ginther OJ, Pierson RA.A linear-array ultrasound scanner with a 5-MHz transducer was evaluated for studying follicular and luteal status in mares, and the ultrasonic properties of equine ovaries were characterized. Follicular diameters were estimated in vivo and after removing and slicing six ovaries. Correlation coefficients between the two kinds of determinations were 0.91 for number of follicles >/=2 mm in diameter and 0.95 for diameter of largest follicle. The ovaries of five mares were examined daily until all mares had been examined from three days before an ovulation to three days after the next ovulation....
Higgins AJ, Lees P.The presence of cyclooxygenase products of arachidonic acid metabolism in carrageenin-induced inflammatory exudate was investigated in ponies using two models. In the first model, an inflammatory response was stimulated by injecting carrageenin into subcutaneously implanted polypropylene tissue cages and exudates were collected at five predetermined times between 3 and 48 h. In the second model, exudates were harvested at 6, 12 and 24 h from carrageenin-impregnated polyester sponges which had also been inserted beneath the skin. Prostaglandin (PG) E2, thromboxane (TX) B2 and the stable breakdo...
McGavin MD, Fadok VA.Skin biopsy for histologic, immunofluorescent, parasitologic, and bacteriologic examination is a common procedure, but for maximum effectiveness the clinician must realize the importance of precautions to select the correct stage of lesion of different diseases; avoiding creating artifacts during removal and fixation; and give full details of history, clinical diagnosis, and differential diagnoses on the laboratory request sheet. Pathology reports describing the subtleties of histologic changes are difficult to write, particularly if the lesions are not specific. Overly long histologic reports...
Held JP, Oliver JW.A study was designed to assess the secretory response of thyroid glands in horses to an economically feasible dose (5 IU) of thyrotropin injected IV, and to establish valid blood sampling periods in cases in which thyroxine concentrations were different from base-line values. Significant (P less than 0.001) response (doubling or near-doubling of base line) occurred as early as 3 hours after thyrotropin administration, with peak response at 4 to 5 hours. It was concluded that administration of 5 IU of thyrotropin is economical and effective in the horse, with collection of a second blood sample...
Sellers AF, Lowe JE, Rendano VT.Transmission of intestinal content with respect to wall position and intraluminal pressure was studied using implanted catheters in portions of the haustrated left ventral colon and nonhaustrated pelvic flexure and left dorsal colon in 3 conscious, standing, and feeding ponies. Wall position and content movement was studied in 1 noncatheterized conscious pony that was standing and eating. When coordinated wall movements involving greater than or equal to 30 cm of adjacent colon were seen, point-to-point content movement accompanied intraluminal pressure peaks occurring in the same direction. N...
Strzemienski PJ, Kenney RM.Mares with sound reproductive tracts were divided into two groups. In Group I (N = 12), uteri were flushed once per oestrous cycle during alternate cycles while in Group II (N = 8) mares were flushed twice in a cycle for 2 contiguous cycles. Total protein concentrations and total recoverable protein of uterine flushings taken on Day 3 of oestrus and Day 8 after ovulation in each of the 2 groups and between the 2 groups did not differ significantly. The length of oestrus and dioestrus was not affected by the flushing procedures. Total recoverable protein and total protein concentrations of flus...
Weaver BM, Lunn CE, Staddon GE.Muscle perfusion was studied in conscious and anaesthetised horses by monitoring the clearance of a locally injected bolus of saline containing radioactive xenon (133Xe). The mean of all the measurements made from the brachiocephalicus and semimembranosus muscles in conscious subjects was 1.29 ml/min/100 g while in anaesthetised subjects it was 0.40 ml/min/100 g. The significance of these results is discussed in relation to the clinical occurrence of post anaesthetic myositis.
Hilbert BJ, Rowley G, Antonas KN.A method previously described was used to determine the hyaluronic acid concentration in synovia from normal and arthritic horse joints. The concentration of hyaluronic acid in the synovia from arthritic joints was found to be significantly lower than the concentration in fluid from normal joints.
Delbeke FT.Urinary concentrations of the beta-antagonist oxprenolol and some of its major human metabolites were determined following oral administration of a dose of 160 mg to five fasted horses. Quantitation was performed by gas chromatography-mass spectrometry (GC-MS) in the selected ion mode (SIM) by monitoring ion m/z 466 of the heptafluorobutyric derivatives. As early as 2 h after dosage oxprenolol could be detected in hydrolysed urine and remained detectable up to 24 h. Maximum urinary concentrations and excretion rates were obtained between 2 and 12 h. After 12 h only 2.8% of the administered dos...
Pace-Owens S.Gamete intrafallopian transfer (GIFT), developed in 1984, was the result of further studies on in vitro fertilization (IVF). Since that time many nurses have worked in settings near in vitro fertilization centers and, therefore, have a basic understanding of the technology. An overview is given of the GIFT procedure to prepare nurses to advise and refer couples who may qualify for GIFT and to highlight the shift in the fertility program nurse coordinator's functions toward the positions of administrator and consultant.
Bossut DF, Leshin LS, Malven PV.Radioimmunoassay procedures were developed and validated for the quantification of beta-endorphin (beta-EP)-like immunoreactivity in equine plasma. beta-EP could be quantitatively extracted from plasma with silicic acid powder and subsequently assayed, however, valid estimates of this hormone could also be obtained on unextracted plasma. Although beta-lipotropin (beta-LPH) cross-reacted in the assay, it was not necessary to correct for beta-LPH activity when assaying unextracted plasma because chromatographic analyses showed that 92% of the immunoreactivity in plasma extracts was similar in mo...
Ghaeli T, Karimi B, Kojouri GA, Dehkordi RR, Ahadi AM.One of the initial responses of the host's innate immunity of newborns against pathogens is the use of oxidative enzymes. This study aimed to evaluate changes in serum xanthine oxidoreductase (XOR) activity, the leukocyte myeloperoxidase (MPO) and XOR genes expression, and some biochemical parameters in healthy Darehshuri newborn foals up to 60 days of life. Blood samples were collected from 16 foals at 1, 7, 15, 30, and 60 days and used for detecting XOR activity, biochemical parameters, and also gene expression by real-time RT-PCR. High activity of XOR was observed at birth, explained by phy...
Becker CK, Savelberg HH, Buchner HH, Barneveld A.To evaluate posttrauma biomechanical behavior of the scar attributable to desmotomy of the accessory ligament of the deep digital flexor tendon (AL-DDFT), compared with the histomorphologic and ultrasonographic appearance. Methods: 5 Standardbred trotters. Methods: Gross appearance, length, cross-sectional area (CSA), in vitro material properties, and ultrasonographic and histomorphologic features were studied 6 months after desmotomy. Tensile tests were conducted, with forces and elongation simultaneously recorded. Surgically treated limbs were compared with nontreated contralateral limbs. Re...
Kirkpatrick CJ, Ernst NS, Trumble TN.There are limited radiographic-guided injection techniques of the insertion of the distal interphalangeal joint (DIPJ) collateral ligaments. The objective of this study was to develop and evaluate a palmar/plantar radiographic-guided injection of the collateral ligament insertion in cadavers. Fifty limbs were used to develop the technique and 24 additional limbs were used to evaluate accuracy. An 18 G, 9 cm spinal needle was placed in the depression between the palmar digital neurovascular bundle and arch of the ungular cartilage with dorsodistal advancement towards the distal phalanx collat...
Makra Z, Eördögh R, Fábián I, Veres-Nyéki K.To compare the corneal anaesthetic effect of 0.5% bupivacaine, 2% lidocaine and 0.4% oxybuprocaine on normal equine eyes. Methods: Prospective, blinded crossover study. Methods: A group of 10 clinically healthy horses. Methods: Corneal sensitivity was determined in each eye by measuring corneal touch threshold (CTT). The study had three phases. Each subject was randomly given one of the three treatments followed by a 72 hour washout period. Every horse received all treatments. Baseline CTT was recorded prior to anaesthetic instillation (T0) then CTT was measured 5 and 10 minutes after (T1 and ...
Wyse CA, Love S, Christley RM, Yam PS, Cooper JM, Cumming DR, Preston T.Oxidative stress refers to an imbalance between the production of oxidising free radicals and the antioxidant defenses of the cell, and is associated with many pathogenic processes. Oxidative damage to cellular lipids results in the evolution of pentane and ethane gas, and detection of these hydrocarbons in the exhaled breath can be used to monitor in vivo oxidative stress. The aim of this study was to validate a gas chromatography (GC) method for measurement of breath pentane in the horse. The GC-system developed showed good specificity for discrimination of pentane from other breath hydrocar...
Cercone M, Brown BN, Stahl EC, Mitchell LM, Fortier LA, Mohammed HO, Ducharme NG.Respiratory function in the horse can be severely compromised by arytenoid chondritis, or arytenoid chondropathy, a pathologic condition leading to deformity and dysfunction of the affected cartilage. Current treatment in cases unresponsive to medical management is removal of the cartilage, which can improve the airway obstruction, but predisposes the patient to other complications like tracheal penetration of oropharyngeal content and dynamic collapse of the now unsupported soft tissue lateral to the cartilage. A tissue engineering approach to reconstructing the arytenoid cartilage would repr...
Kilcoyne I, Nieto J, Magdesian KG, Nottle BF.To determine the effect of a 10% dimethyl sulfoxide (DMSO) solution on the peak concentration (C ) of amikacin in the radiocarpal joint (RCJ) during intravenous regional limb perfusion (IVRLP) compared with 0.9% NaCl. Methods: Randomized crossover study. Methods: Seven healthy adult horses. Methods: The horses underwent IVRLP with 2 g of amikacin sulfate diluted to 60 mL using a 10% DMSO or 0.9% NaCl solution. Synovial fluid was collected from the RCJ at 5, 10, 15, 20, 25, and 30 minutes after IVRLP. The wide rubber tourniquet placed on the antebrachium was removed after the 30 min sample. A...
Cuervo-Arango J.Prostaglandins (PGs) are essential to trigger the cascade of events that degrade the extracellular matrix of follicles leading to follicular rupture and ovulation. In mares, systemic administration of flunixin meglumine (FM), a PG synthetase inhibitor, blocks ovulation by inducing luteinized unruptured follicles (LUF). In the rat, the administration of PGF(2α) (PGF) and PGE restored ovulation in indomethacin treated animals. The mares were treated with FM 0, 12, 24 and 36 h after human chorionic gonadotrophin (hCG) administration to induce experimentally LUF (n = 15) or were left untreated (c...
Davies HM.A photoelastic method used for materials testing in industry was adapted to show the distribution of strain through the hoof wall in the living horse. Strain was a change in length per unit length in the material of the loaded hoof wall compared with the unloaded condition. Coloured fringes appeared in the photoelastic plastic where there were differences in strain between adjacent sites (strain gradients) in the hoof. Strain distribution was observed in the shod and unshod hoof wall of the front hooves of 6 sound horses with hooves that appeared 'good' to visual inspection, and one unsound ho...
Mader Ch, Geisel O, Gerhards H, Hermanns W.In the present work transponders of 2 identification systems have been implanted on an exactly defined site at the bottom of the ear on 28 horses. The Backhome system is easier to handle and less complicated than the trovan system since it is smaller and handier. The hemorrhages that had occurred after the injection were mild at 17 animals and moderate at 4 animals. Inflame changes at the injection site post application were limited to minor swellings (n = 3) and minor pain (n = 6). The interrogator's scope of the two transponder systems is different. The interrogator's scope of the trovan tra...
Olson NC.Effects of endotoxemia on lung water, hemodynamics, and gas exchange were determined in ponies breathing a mixture of halothane and 100% O2. Escherichia coli endotoxin was infused IV at 20 micrograms/kg of body weight for 1 hour followed by 10 micrograms/kg/hr the subsequent 4 hours. By 0.25 hour, endotoxin increased mean pulmonary artery pressure and pulmonary vascular resistance; this was followed by a return to base-line values by 0.5 and 1 hour, respectively. A 2nd increase in pulmonary vascular resistance occurred by 5 hours of endotoxemia. During the last 2 hours of endotoxin infusion, c...
Sweeney CR, Habecker PL, Russell GE.To evaluate the safety of sodium bisulfate for use in horse barn environments by determining its irritant effect on skin and hooves. Methods: 6 female mixed-breed ponies. Methods: Sodium bisulfate was applied to clipped intact skin of 6 ponies to evaluate its irritant effect after single (48 hours) and repetitive (6 h/d for 10 days) applications; similar areas of skin were used as untreated control sites. In addition, sodium bisulfate was applied to the sole of both front hooves of each pony and covered with wet gauze, and the entire hoof was covered with adhesive tape for 48 hours. Results: C...
Pozor MA, Benson SM, Macpherson ML, Kelleman AA.Transplantation of stem cells into dysfunctional testes is currently being investigated as a therapeutic option for men and stallions with advanced testicular degeneration. This series of "proof of concept" studies aimed to identify a safe and efficient method of inducing severe testicular degeneration to create an optimal equine recipient model for intratesticular stem cell transplantation (SCT). Two ex vivo and two in vivo experiments were conducted. At first, forty testes obtained from castrations were used to identify an effective therapeutic ultrasound (TUS) device and the protocol for ...
Spoormakers TJ, Donker SH, Ensink JM.The anaesthetic potency, onset of action, duration of action, and side effects of lidocaine and lidocaine plus epinephrine for proximal metacarpal block of the lateral and medial palmar nerves were determined. Ten horses were used and legs were injected using a cross-over model with three test solutions: 1) solvent and lidocaine (2%) plus epinephrine (SLE); 2) solvent and lidocaine (2%) without epinephrine (SL); and 3) solvent only (S). The contra-lateral leg was injected with saline (placebo; P). In both the SL and SLE groups, the onset of anaesthesia occurred between 5 and 15 minutes after i...
Folz SD, Hanson BJ, Griffin AK, Dinvald LL, Swerczek TW, Walker RD, Foreman JH.Ceftiofur sodium was evaluated as a therapy for respiratory infections in horses. This cephalosporin antimicrobial was administered intramuscularly every 24 h and at a dose of 2.2 mg/kg (1.0 mg/lb) of body weight. The efficacy of ceftiofur sodium was compared with that of a positive control drug, ampicillin sodium (recommended dose of 6.6 mg/kg [3 mg/lb], given every 12 h). Both treatments were continued for 48 h after clinical symptoms were no longer evident (maximum of 10 days). Fifty-five (55) horses with naturally acquired respiratory infections were included in the study; 28 were treated ...
Simoens P, Lauwers H, De Muelenare C, Muylle E, Steenhaut M.A clinical case of Horner's syndrome is described in a Standardbred horse, and the various symptoms of cranial sympathetic denervation are studied in two ponies after experimental transection of the left cervical sympathetic trunk and vagosympathetic trunk, respectively. The most prominent symptoms of equine Horner's syndrome were ptosis, local sweating and increased cutaneous temperature in the denervated area. Enophthalmos, miosis and increased lacrimation were also observed but these symptoms were mild, variable and difficult to ascertain. Prolapse of the third eyelid was not noticed. Conco...
Kay PH, Dawkins RL, Bowling AT, Bernoco D.Plasma or serum samples from 12 Arabian and 181 standardbred horses have been typed using an immunofixation technique to determine electrophoretic polymorphism of equine third complement component (C3). Six distinctly different electrophoretic patterns of equine C3 have been recognized thus far. SDS PAGE analysis of equine C3/anti C3 complexes revealed that the submolecular structure comprised an alpha chain and beta chain of molecular weights approximately 118,000 and 63,000 daltons respectively. The molecular weights of the alpha and beta chains were similar in all electrophoretic variants t...
Sweeney CR, Weiher J, Baez JL, Lindborg SR.The endobronchial anatomy of 12 lung specimens from horses and 12 healthy, standing, sedated horses was evaluated, using a 200-cm-long, 9.5-mm-diameter videoendoscope. On the basis of these findings, the nomenclature system of Amis and McKiernan was modified for identification of airways of horses during bronchoscopy. Lobar bronchi are identified on the basis of the side of the bronchial tree on which they were found and the order in which they originated from the primary bronchus. Thus, RB1, RB2, and RB3 referred to right cranial lobar bronchus, respectively. On the left side, the designation...
Marquardt SA, Wilcox CV, Burns EN, Peterson JA, Finno CJ.Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM) is a neurologic disease that has been reported in young horses from a wide range of breeds. The disease is inherited and associated with vitamin E deficiency during the first two years of life, resulting in bilateral symmetric ataxia. A missense mutation (chr3:71,917,591 C > T) within adhesion G protein-coupled receptor L3 (ADGRL3) was recently associated with risk for EDM in the Caspian breed. In order to confirm these findings, genotyping of this missense mutation, along with the three other associated single nuc...
Delbeke FT, Teale P, Debackere M, Houghton E.A commercially available generic promazine ELISA kit is available which shows cross-reactivity for the tranquilizer chlorprothixene (CPT). The ELISA test readily detects the presence of CPT or its metabolites in equine urine for up to 24 h after the i.v. and i.m. administration of sub-therapeutic doses (4.5 mg) to three horses. Maximum concentrations (CPT equivalents) are obtained 2 h after i.v. dosing. No distinct concentration peak values are observed after i.m. administration. Following solid-phase extraction, confirmation of CPT and its metabolites by electron impact mass spectrometry afte...
Black B, Cribb NC, Nykamp SG, Thomason JJ, Trout DR.Artefacts caused by regional anaesthesia can influence image interpretation of ultrasonography and nuclear scintigraphy. Perineural and intrasynovial anaesthesia are commonly performed prior to magnetic resonance imaging (MRI); and the effects on MR images, if any, are unknown. Objective: To determine if perineural and intrasynovial anaesthesia of structures in the equine foot cause iatrogenic changes detectable with MRI. Methods: A baseline MRI examination of both front feet was performed on 15 horses, 2-6 days prior to mepivacaine injection adjacent to the lateral and medial palmar digital n...
Kolm G, Knapp E, Wagner R, Klein D.Interleukin-1beta (IL-1beta) is a primary cytokine of the skin that has a pivotal role in keratinocyte differentiation, epidermal wound healing and host defense. Pathological increase of cutaneous IL-1beta is associated with edema formation, epidermal hyperproliferation and atopic dermatitis in humans. However, in horses the role of cutaneous IL-1beta in edema formation and allergic skin disease has not been characterised so far. Particularly in Culicoides hypersensitivity (CHS), intradermal injection of Culicoides extract may be associated with enhanced transcription of local IL-1beta. To exa...
Alonso Jde M, Rodrigues KA, Yamada AL, Watanabe MJ, Alves AL, Rodrigues CA, Hussni CA.Heparin is routinely administered in postoperative abdominal surgery aiming to prevent adhesions formation; however, there is no consensus indicating its effectiveness. This study evaluated the effect of heparin on peritoneal reactivity after abdominal surgery, through the association between peritoneal fluid features and ultrasonographic and laparoscopic examination. Ten adult horses were used: control group (CG) and treated group (TG). Both groups underwent laparotomy and small colon enterotomy. TG received subcutaneous heparin at 150 IU/kg every 12 hours for 5 days. The animals underwent ...
Iacono E, Merlo B, Rizzato G, Mislei B, Govoni N, Tamanini C, Mari G.The aim of the present study was to verify how repeated ovum pick-up (OPU), performed in anestrous and cyclic mares, affect ovarian activity, measured by progesterone (P4) and 17ß-estradiol (E2) plasma levels. Ovum pick-up of all visible follicles was performed every 9 to 12 days, and four sessions were carried out during anestrous (A) and breeding season (BS). The number of aspirated follicles per mare at each session was not significantly different between the two periods (BS: 6.1 ± 2.4; A: 7.5 ± 4.4; P > 0.05), but the mean follicular diameter was significantly higher during BS (16.0 ...
Garza F, St George RL, Mitchell PS, Thompson DL.An experiment was conducted to determine whether partial neutralization of estrogens via active immunization alters testosterone propionate (TP)-induced increases in FSH secretion after GnRH administration in ovariectomized pony mares. Twenty mares were used in a 2 X 2 factorial arrangement of treatments (n = 5/group). Factor 1 was long-term active immunization against either bovine serum albumin (BSA) or estrone-17-oxime-BSA. Factor 2 was 11-d administration of either vehicle (vegetable oil) or TP (175 micrograms/kg BW). Plasma concentrations of FSH were not affected (P greater than .1) by ei...
Camillo F, Cela M, Vannozzi I, Romagnoli S, Aria G.Fourteen normal, cyclic mares, treated to synchronise oestrus and ovulation and inseminated artificially with fresh semen, were assigned to a donor or a recipient group after ovulation, with the aim of obtaining a degree of synchrony of > or =2 days. Ten embryos, collected on Day 6 or 7 after ovulation (Day 0), were transferred nonsurgically to inseminated recipient mares (IRM) that had ovulated up to 5 days after the respective donors, or to pregnant recipient mares (PRM) that had ovulated 2-7 days before the donors. Embryonic size and development, as determined by ultrasound examination, wer...
Robert M, Manet H, Manneveau G, Geffroy O. The aim of this study was to describe an ultrasound-guided injection technique of the lumbosacral disc in horses through the cranial vertebral notch of the sacrum and to evaluate both accuracy and potential complications of the technique on equine cadavers. Methods: Twenty-four injections of the lumbosacral area were performed on 12 equine cadavers shortly after euthanasia under ultrasound guidance with the horse in recumbency using two different dyes (one colour for each side). The lumbosacral area was dissected in each horse and the accuracy of the technique, as well as its potential c...
