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.
Sorenson PR, Robinson NE.Quasi-static pressure-volume curves and single-breath nitrogen washouts were performed simultaneously on eight anesthetized horses (average body wt = 485 kg) in left lateral, right lateral, prone, and supine postures (sequence randomized). The shift from prone to lateral or supine posture decreased expiratory reserve volume (ERV), vital capacity (VC), residual volume (RV), functional residual capacity (FRC), and total lung capacity (TLC); RV and FRC expressed as %TLC were unchanged, suggesting that in the lateral and supine postures a significant portion of the lung volume was not recruited by...
Tisserand JL, Boulard F, Deponge P.We studied a caecum-cannulated pony fed hay libitum in order to determine the mineral elements likely to cause deficiencies which decrease microbial activity in the caecum. During four successive 1-month periods, we observed the effects of adding 50 mg of iron, 1 mg of cobalt, 40 mg of copper and 200 mg of zinc, respectively. Except for the introduction of zinc, which greatly diminishes cellulolytic activity measured with the nylon bag technique, there was no significant modification in that activity as shown by pH, NH3-nitrogen, total nitrogen and volatile fatty acid production (table 1). It ...
Malan FS, Reinecke RK.A single oral dose of fenbendazole (FBZ) at 10 mg/kg body mass was given to 5 donkeys. A further 5 donkeys were dosed with a medicated lick (1 mg FBZ/g lick) until the oral consumption was 10 mg/kg body mass. In both trials FBZ was highly effective against adults of the following genera: Cyathostomum, Cylicocyclus, Cylicostephanus, Cylicodontophorus, Poteriostomum, Cabellonema, Craterostomum and Triodontophorus; similarly high efficiency was obtained against the following species: Habronema majus, Habronema musca, Strongylus vulgaris and Oxyuris equi and worms identified as belonging to the su...
Sellers AF, Lowe JE, Brondum J.The equine large colon is the major cellulose-fermentation locus of these species. The area of juncture of the ventral and dorsal divisions of the equine large colon was characterized, in 13 chronic unanesthetized animals and in 25 in vitro preparations, as an area of resistance to aboral flow. This is a probable pacemaker area. The reservoir function of this part of the colon is apparently facilitated by the presence of a pacemaker at this level. There was a general rise in recorded intraluminal pressure peaks during the first hour of feeding. This characteristic was not altered after resecti...
Brown JE, Corstvet RE, Stratton LG.Two experiments incorporating 13 mares were conducted for the purpose of producing and monitoring intrauterine infection with Klebsiella pneumoniae. In the pilot study, the infection was produced with strains of K pneumoniae type 68 and type 10 isolated from the genital tract of stallions with a history of breeding problems. In the principal study, K pneumoniae type 68 was used to produce the infection. Tampons and guarded culture swabs were used to obtain uterine samples in the pilot study. In comparing the efficacies of isolation of K pneumoniae with the tampons and isolation with standard g...
Allen WE, Kessy BM, Noakes DE.Two experimental procedures were investigated in order to assess their usefulness in diagnosing occlusion of the equine uterine tube. The starch grain test, which involves the injection of a starch suspension onto the ovary and the subsequent recovery of starch from the cervix, proved to be safe and reliable. Each tube could be investigated separately. It was found that when starch was injected onto the ovulating ovary on the day of ovulation, there was a delay of four to seven days before starch was recovered from the cervix. The phenolsulphonphthalein (PSP) test, which involves the depositio...
Roberts MC, Norman P.The absorption of d-xylose forms the basis of a useful screening test in the investigation of small intestinal disorders in the horse. A comparison has been made of different assay methods and there was no significant difference between the results obtained with the parabromoaniline (PBA) method or the ferric chloride-orcinol (FCO) method. The orthotoluidine method was unsatisfactory. The anticoagulant agent did not affect the test. A dose of 0.5 g commercial grade xylose/kg body weight as a 10 per cent solution given by stomach tube, produced a peak plasma xylose level after 90 min and should...
Splitter GA, Incefy G, Iwata T, McGuire TC.Arabian horses with severe combined immunodeficiency disease (SCID) were evaluated for thymic hormone activities using thymic extracts and sera. Extracts prepared from thymus of SCID horses were able to increase the number of spleen cells responding to sheep red blood cells in irradiated, bone marrow-reconstituted mice. In addition, ultrafiltrates prepared from sera of these immunodeficient horses, which contained material with molecular weight of less than 50,000 Daltons could (a) induce a population of human bone marrow precursor cells to differentiate into cells bearing SRBC receptors and f...
Haliburton JC, Vesonder RF, Lock TF, Buck WB.Signs and lesions characteristic of equine leucoencephalomalacia were produced in one of two donkeys given corn cultured with Fusarium moniliforme Sheldon. Gross and histopathologic lesions of the cerebrum included an extensive necrotic cavitation within one cerebral hemisphere, disruption and rarefication of the subcortical white matter, prominent perivascular hemorrhage, and some mononuclear cell perivascular cuffing. Another donkey and three rabbits fed the cultured corn did not develop characteristic signs or lesions of the toxicosis. Chick bioassay studies indicated that the cultured corn...
Prescott JF, Markham RJ, Johnson JA.Transformation of peripheral blood lymphocytes from pony foals vaccinated and subsequently infected with Corynebacterium equi was studied. Three foals were vaccinated on two occasions using a formalinized C. equi vaccine with aluminum hydroxide as an adjuvant. Three nonvaccinated foals served as controls. Foals were challenged intratracheally with 9 x 10(9) C. equi six weeks after the initial vaccination. Foals survived this infection for one to two weeks. Significant lymphocyte transformation in response to C. equi antigens was detected in two vaccinated foals at the third week after initial ...
Deem DA, Traver DS, Thacker HL, Perryman LE.Immunologic deficiency was suspected in an 18-month-old Standardbred horse with persistent fever, multifocal bacterial infection, and neutropenia with a large number of immature neutrophils. Serum protein electrophoresis revealed marked depression of the gamma-globulin fraction (0.2 g/100 ml). Immunologic testing and histologic examination of lymphoid tissues identified the immune deficit as agammaglobulinemia. Serum concentrations of immunoglobulin (Ig)G and IgG(T) were initially low and declined with time; IgM and IgA were not detectable. The horse failed to produce antibodies when inoculate...
Steffey EP, Johnson BH, Eger EI, Howland D.Breathing 79% nitrous oxide (N2O) in oxygen increased the rate of accumulation of bowel gas during intraluminal bowel segment infusions of hydrogen, methane (CH4), air, or carbon dioxide (CO2) in four pentobarbital-anesthetized dogs more than did breathing 100% oxygen. A N2O-associated increase in the volume of naturally produced intestinal gas in five halothane-anesthetized ponies corroborated the findings in the dog studies. In a second group of four dogs a bolus of CH4 or CO2 was injected into the bowel lumen. When the dogs breathed O2 the bowel gas volume decreased. Gas was virtually absen...
Valdez H, Scrutchfield WL, Taylor TS.Eight horses ranging in age from 4 days to 9 years were treated for peritonitis. Escherichia coli was isolated in four cases and Nocardia sp in one case. In each case, a catheter placed in the peritoneal cavity allowed drainage of a large amount of purulent fluid. Retrograde peritoneal lavage was performed through a Foley catheter or medical tubing, using Ringer's lactate solution containing kanamycin, povidone iodine, or nitrofurazone. All except two horses responded well to repeated lavage.
Orr JA, Busija DW.Unanesthetized ponies were given 4% CO2 (inspired CO2 pressure = 28 Torr) to breathe at two levels of arterial O2 pressure (PaO2): 1) near 75 Torr and 2) near 200 Torr. During 4% CO2 breathing, at either level of PaO2, the mean arterial CO2 pressure (PaCO2) was unchanged from control measurements (control measurements were made at the same PaO2, but with no CO2 in inspired air), suggesting that awake ponies can "clear" 4% CO2. The ability of individual ponies to clear 4% CO2 was quite variable: some ponies did not clear 4% CO2 and others cleared 4% CO2 on one day but not on the following day. ...
Campbell DL, Douglas LW, Ramge JC.Siliconized rubber tubes were used to cannulate one oviduct in 7 mares, and secretions were collected in a polycarbonate container located externally, in the region of the left paralumbar fossa. Secretion rates were recorded daily during the estrous cycle. Concentrations of calcium, magnesium, sodium, potassium, inorganic phosphorus and glucose were determined in the oviduct fluids secreted throughout the estrous cycle. Secretion rates were greatest during estrus (days 1-9), with a significant decrease (P<.01) noted during nonestrus (days 10-21). Concentrations of all constitutents measured...
Foster JP, Evans MJ, Irvine CH.Mares at different stages of the oestrous cycle were given a single intravenous injection of 0.5 mg synthetic Gn-RH. The mean area of the induced LH peak was significantly less at mid-cycle (Day 10-11) than at any other time. The mean height of the LH peak above preinjection concentration was greater at late oestrus and early cycle (Day 5-6) than at mid-cycle and early oestrus. There were no significant different in mean FSH responses. The LH:FSH ratio for both height and area of induced peaks was significantly less at mid-cycle than at other times of injection. These results suggest that one ...
Smith HJ.From 1967--1978 observations were made on the presence of the small equine pinworm, Probstmayria vivipara, in seven experimental ponies. The life cycle of this nematode is unusual in that it is endogenous with development of all stages occurring within the host's digestive tract. Initially, worms were found in the feces of four of seven ponies following treatment with thiabendazole but the infection was later transmitted to all ponies possibly via coprophagy. Still later, based on fecal and postmortem examinations, four of the seven ponies lost their pinworm burdens. At necropsy, the principal...
Hajji MA, Wilson TA, Lai-Fook SJ.The continuum solution for the deformation of an elastic half space covered by a membrane is used to interpret measurements of the indentation of lung lobes under a column of fluid. The shear modulus mu of the underlying parenchyma is found to be approximately 0.7 times transpulmonary pressure, independent of species size. The tension in the pleural membrane T increases rapidly with increasing membrane area. For dog lungs, the value of T is 10(3) to 10(4) dyn/cm. For the larger species tested, pigs and horses, T is larger. The continuum solution shows that a concentrated force applied to the p...
Matthews AG.Three major antiprotease components in equine serum were identified and characterised. These were the acidic prealbumin Pr, the homologue of human alpha-1 antitrypsin and 2 protease binding proteins, the acidic prealbumin Xc and alpha-2 macroglobulin, both capable of inhibiting the proteolytic activity of trypsin, but with only limited inhibitory effect on its esterolytic activity. The possible role of these serum antiproteases in the onset of chronic obstructive pulmonary disease (COPD), analogous to the hereditary dysproteinaemia of alpha-1 antitrypsin in man, was investigated. There was no ...
McPherson EA, Lawson GH, Murphy JR, Nicholson JM, Breeze RG, Pirie HM.Micropolyspora faeni and Aspergillus fumigatus were identified as common causes of respiratory hypersensitivity in horses affected with chronic obstructive pulmonary disease (COPD). Rye grass pollen and an Actinomycete evoked respiratory allergy in a few horses. Not infrequently, individual horses were found to have respiratory hypersensitivity to two or more antigens. The methods used to examine for allergy were intradermal testing and inhalation challenge with environmental antigens. An intradermal test using an M faeni extract was demonstrated to be suitable for diagnostic use in horses pre...
Taverne MA, van der Weyden GC, Fontijne P, Dieleman SJ, Pashen RL, Allen WR.Uterine electromyography was performed by means of chronically implanted surface electrodes in 3 Pony mares during spontaneous oestrous cycles and following luteolysis induced by a prostaglandin analogue (fluprostenol). Three distinct patterns were recognized during the oestrous cycle. (1) During oestrus well defined phases of activity with closely grouped high-amplitude spikes were separated by long periods (10-45 min) of complete inactivity. (2) During dioestrus more diffuse phases of activity with low-amplitude spikes were separated by variable periods of relative inactivity. (3) During lut...
Gelberg H, Cockerell GL, Minor RR.The outer medullary (juxtacortical) zone of a normal equine adrenal gland had columnar chromaffin-positive cells arranged with their long axes perpendicular to fine vascular channels. The deeper medullary regions were composed of smaller irregularly round to polygonal chromaffin positive cells in small packets. Both cell types contained two types of membrane-bound cytoplasmic secretory granules. Osmiophilic granules with a homogeneous core, crenated membrane and narrow submembranous halo predominated in the columnar juxtacortical cells. The rounder, central medullary cells contained predominan...
Frankland AL.The skin grafting experiments were carried out on the cannon regions of horses to throw light on four matters relating to split skin transplantation. They were: The thickness of donor split skin that would provide good wound cover and still leave adequate tissue to permit uneventful healing at the donor site; whether split skin grafts were more readily accepted on fresh than on granulating wounds; the size of wounds that would benefit from grafting; and the maximum size of graft that would be readily accepted. The findings were: Split skin grafts 0.76 mm thickness gave the best results althoug...
Imai S, Ozeki K, Fujita J.The surface structure of the ciliary zone in 13 species of ciliates found in the large intestine of the horse was observed by scanning electron microscopy. In Holophryoides ovalis many fine depressions considered to be a result of phagocytosis or pinocytosis in the naked cytostome were noticed. In Blepharocorys spp. a distinct section was present between the portion with cilia and that without cilia. It was not present, however, in some species of the family Buetschliidae, such as Bundleia postciliata and Didesmis spp. The species of Entodiniomorphida had a lip around the ciliary zone with cil...
Wang Y, Zhang XY, Wei LL, Wu DL, Wang XJ, Xiang WH, Shen RX, Shao YM.To evaluate the relationship between the transcriptional level of IFN-gamma mRNA in peripheral blood mononuclear cells (PBMC) and immune protective response driven by inoculated horses with donkey leukocyte attenuated vaccine of EIAV(DLV), and to elucidate the immune mechanism of DLV. Methods: A real-time PCR method was established for quantitative detection of IFN-gamma mRNA level from horse PBMCs. Twelve horses were divided into vaccination group, healthy control group, challenging control group and EIAV natural infection group. The transcriptional level and distribution of IFN-gamma mRNA in...
Sinclair CD, Webel SK, Douthit TL, Murray LW, Jager AL, Grieger DM, Kouba JM.The objective of these studies was to investigate the efficacy of an intravaginal triptorelin acetate (TA) gel as an ovulation-inducing agent in mares. In Exp. 1, 24 mares were blocked using a combination of parity and age and randomly assigned to 1 of 3 treatment groups: 5 mL TA gel (TA5), 10 mL TA gel (TA10), or 5 mL vehicle gel only (CON). Following the appearance of a follicle ≥ 25 mm, a blood sample was obtained for measurement of LH from each mare every 24 h until treatment administration. When a follicle ≥ 35 mm was observed, treatments were administered intravaginally. Following tr...
Fintl C, Ihler CF.D(+)-xylose absorption tests are commonly performed when investigating suspected small intestinal malabsorption in the horse. The test involves the administration of a D(+)-xylose solution via a nasogastric tube followed by serial blood sampling to determine its rate of absorption. In some horses, nasogastric intubation cannot be safely performed without prior administration of a sedative. Due to its short duration of action, the α(2) agonist xylazine is commonly used for this purpose. However, α(2) agonists have also been reported to influence the rate of gastric emptying as well as small i...
Lee JY, Kang TY, Lee YD, Shin TK.The binding specificities of various lectins, such as the Dolichos biflorus agglutinin (DBA), soybean agglutinin (SBA), and the Bandeiraea simplicifolia BS-1 (Isolectin B4), Triticum vulgaris (WGA), Arachis hypogaea (PNA), and Ulex europaeus (UEA-I) lectins, were studied in the vomeronasal organ of the horse. The microvilli of the vomeronasal sensory epithelium were positive for DBA, SBA, Isolectin B4, WGA, PNA, and UEA-I. The receptor cells showed intense reactivity for DBA and WGA. Lectins were not detected in the supporting cells or basal cells. The Jacobson's glands were positive for WGA a...
Dos Reis WVA, de Braga D, Júnior MV, Gheller JM, de Deco-Souza T, da Costa E Silva EV, Sampaio BFB, Macedo GG.Dispersed ovulation at the breeding (BS) and anestrus at non-breeding season (NBS) are major impediments to embryo transfer and insemination programmes. The present study aimed to evaluate a hormonal P4/E2-based synchronisation protocol in mares during both the BS and the NBS on ovarian/follicle behaviour. Mares underwent a hormone protocol to synchronise their ovulation during the BS (n = 8) and NBS (n = 10), starting (D0) with the insertion of an intravaginal device containing 1 g of P4 and 7 mg Estradiol Benzoate IM. (EB). On D9, the device was removed and injected with 0.25 mg o...
Bland SA, Blake JW, Ray RS.Mefenamic acid is extracted from biological fluids and is acylated with pentafluoropropionic anhydride to form a derivative possessing high electron affinity. The derivative is analyzed by gas-liquid chromatography with an electron capture detector. The method is particularly valuable for determining drug levels in blood where small sample and/or drug concentrations are available.
Moorman VJ, Marshall JF, Devine DV, Payton M, Jann HW, Bahr R.Radiographic diagnosis of equine bone disease using digital radiography is prevalent in veterinary practice. However, the diagnostic quality of digital vs. conventional radiography has not been compared systematically. We hypothesized that digital radiography would be superior to film-screen radiography for detection of subtle lesions of the equine third metacarpal bone. Twenty-four third metacarpal bones were collected from horses euthanized for reasons other than orthopedic disease. Bones were dissected free of soft tissue and computed tomography was performed to ensure that no osseous abnor...
Pecheur M.A number of good anthelmintic drugs are currently available which eliminate gastrointestinal nematodes of equids with over 90% success. This is shown by comparing results of critical tests conducted with 9 anthelmintic agents on ponies using the following dosages: 19 mg/kg for Pyrantel embonate, 10 mg/kg for Oxfendazole, 10 mg/kg for Mebendazole, 5 mg/kg for Albendazole, 40 mg/kg for Dichlorvos, 44 mg/kg for Thiabendazole, 7.5 mg/kg, for Fenbendazole, 20 mg/kg for Cambendazole and 7 mg/kg for Parbendazole. From 6 to 9 ponies were treated with each of these anthelmintic agents. Based on total a...
Kelley DE, Schnobrich MR, Gayer S, Scoggin C, Bradcamp E, Canisso IF.The objective of this study was to compare a commercially available leukocyte esterase strip test with endometrial cytology in diagnosing endometritis and establish a cutoff point, sensitivity, and specificity for the leukocyte esterase test (LET). Forty-six light breed mares presented for breeding management were enrolled in this study. Transrectal palpation and ultrasonography examinations were performed to determine when the mares were in estrus. Kalayjian endometrial swabs were used for culture, cytology, and the LET by using the cap to retrieve an endometrial scraping. Thirty-six mares ha...
Gerlach K, Mader D, Delling U, Theuß T, Müller K, Offhaus J, Berner D.The aim of the present study was to verify the diagnostic validity of low-field magnetic-resonance-imaging (MRI) findings in septic diseases of the foot region following penetrating sole injuries caused by nails. Methods: MRI examinations were performed in 10 horses with injuries in the foot region. The diagnostic findings were validated by conventional methods (clinical, surgical, radiological, sonographic, and computed tomographic findings and/or post-mortem histological examination). Results: Navicular bone involvement was revealed most accurately, with a high degree of predictability, and ...
Southwood LL, Lindermann J, Zarucco L, Driessen B, Olander H, Habecker P, Birks EK, Frisbie DD.Growth factors (GF) are important for maintenance and repair of intestinal mucosal structure and function, but there have been no studies investigating growth factor (GF) or growth factor receptor (GF-R) mRNA expression in the intestine of horses with large colon volvulus (LCV). Objective: (1) To determine mRNA expression for epidermal growth factor (EGF), EGF receptor (EGF-R), insulin-like growth factor-I (IGF), IGF receptor (IGF-R), vascular endothelial growth factor (VEGF) and VEGF receptor (VEGF-R) in the intestine of horses with an LCV compared to normal intestine. (2) To measure the corr...
Camacho CA, Estradé MJ, Cazales N, Caballeros JE, Fiala-Rechsteiner SM, Neves AP, Mattos RC.This experiment aimed to verify if the proteins present in a 13 day conceptus induce changes in the equine endometrial ultra-structure, histology, and vascularization, two days after its infusion. Ten healthy cyclic mares were used. Once estrus was confirmed, mares were examined daily to detect ovulation (day 0). After ovulation, mares were examined daily until day seven by transrectal palpation and B-mode and Doppler ultrasonography. In this first cycle, intrauterine biopsies were collected at day seven after ovulation, constituting the Cyclic group (n = 10). In the second cycle, the same mar...
Knoll U, Strauhs P, Schusser G, Ungemach FR.Olsalazine sodium (Dipentum*) has been used therapeutically against inflammatory bowel disease in human medicine as an alternative to sulphasalazine over the past 20 years. Bacteria in the colon split this prodrug into two molecules of the locally effective 5-aminosalicylic acid (5-ASA). Considering the potential therapeutic use in equine colitis, the pharmacokinetics of olsalazine (OLZ) after single oral administration to six horses at a dosage of 30 mg/kg was investigated. Plasma concentrations of OLZ, 5-ASA, and its main metabolite N-acetyl-5-aminosalicylic acid (Ac-5-ASA) were analysed by ...
Davies JV, Gerring EL.Motility patterns in the equine small intestine were investigated in eight ponies. Muscular activity was assessed by means of extramural strain gauge transducers, bi-polar electrodes and in three of the animals, fitted with Thiry-Vella loops, the transit of fluid. Circular muscle contractions were preceded by spiking superimposed on the slow wave and fluid transit in the loops correlated with both these events.
Rodrigues LT, Segabinazzi LG, Oliveira SN, Frasson M, Papa FO.Pregnancy rates after embryo transfer (ET) are disappointing in donkey species. This study aims to report two successful ET of mini-donkey embryos using Brazilian Northeastern jennies as recipients. Eighteen embryo flushes were performed 9 days post-ovulation in two non-pregnant mini-donkeys jennies (11 and 7 cycles per jenny). Eleven embryos (61%, 11/18) were collected and transferred to Brazilian Northeastern jennies 4-6 days post-ovulation by conventional (n = 6) or an alternative (n = 5) technique. The alternative method consisted of inserting a Polansky equine vaginal speculum smear...
McGrath BM, Scott CJ, Wynn PC, Loy J, Norman ST.Managing the return to regular cyclicity after the winter anestrous period in the mare has been a challenge for the equine breeding industry. Specifically, efforts have been made to shift or shorten the vernal transition period and to have it followed by a predictable first ovulation at the commencement of the breeding season. Intravenous administration of kisspeptin is known to stimulate an LH response in both reproductively active and inactive mares. This study examined the effects of a constant rate infusion (CRI) of kisspeptin on mares during vernal transition. Mares were given a 30 hours...
Davies JV, Gerring EL.Small intestinal ischaemia is a cause of pain in man and horses. Occlusion of the vascular supply to Thiry loops in experimental ponies caused severe discomfort and loss of motility within a few minutes but these effects could not be reproduced by a similar procedure in intact gut preparations. However, embolisation of the mural vascular network produced ischaemia of the small intestine of anaesthetised ponies which led to a cessation of motility in the affected segments, though unaffected segments became hypermotile with a characteristic motility pattern. These results suggest the need for re...
Hardeman LC, van der Meij BR, Lamers AA, van der Kolk JH, Back W, Wijnberg ID.In equine medicine the use of Botox® is experimental. Dosages are determined from human treatment-protocols and limited numbers of equine studies. Determination of target-muscle volume can be helpful to extrapolate human dosages. The aim of the study was to calculate a formula enabling the estimation of the deep digital flexor muscle (DDFM) volume based on distances between anatomical landmarks. Nineteen cadaveric limbs were collected and distance A (top of olecranon to Os carpi accessorium) and B (circumference of limb) were measured. Converting mathematical formulas, C was calculated: π ×...
Wensvoort P, Steenbergen-Botterweg WA.When adipose tissues of horses and ponies affected with generalized steatitis were extracted by acetone, methanol and chloroform, non-extractable lipids were found to be present, which had become insoluble as a result of peroxidation and polymerization and had acquired autofluorescent characteristics. The origin of these lipids varies. Peroxidation occurs in three different lipid compartments, namely in the cytoplasm of the necrotized adipose cells, in the macrophagess and in the fat globules present in stroma.
Van Hoogmoed LM, Nieto JE, Spier SJ, Snyder JR.To evaluate the efficacy of a customized solution to attenuate intestinal injury following 20% low-flow ischemia and reperfusion in the jejunum of horses. Methods: 10 healthy adult horses. Methods: Two 30.5-cm-long segments of jejunum were exteriorized through a ventral midline incision and the mesenteric artery and vein supplying that portion of the intestine were instrumented with flow probes. Blood flow was decreased to 20% of baseline for 90 minutes followed by 90 minutes of reperfusion. In 5 horses, 60 mL of the customized solution was placed in the lumen of each segment (treatment-group ...
Scardia A, Mariani Pimenta EL, Ross Russell RI, Jones GJ, Staffieri F.The aim of this study was to evaluate the validity of the SpO/FiO diagram in estimating gas exchange in horses under general anaesthesia. In this prospective, controlled clinical study were included 10 horses under general anaesthesia. FiO was progressively reduced with the following steps: 0.6, 0.4, 0.3 and 0.21; SpO was recorded at each step. An arterial blood sample was collected at the steps of 1.0 and 0.21, to calculate intrapulmonary shunt with the Fshunt formula. The Fshunt value calculated at 0.21 FiO was defined as "Fshunt 0.21", the one calculated at 1.0 FiO as "Fshunt 1.0". The FiO ...
Cartee RE, Cowles WR.To determine the lines of maximum extensibility of the skin over the equine carpus, round puncture wounds were made 2.0 cm apart over the carpal area of 5 horses (7 carpi). The direction of elongation of the round puncture wound was observed and photographed. Lines of maximum extensibility that occurred over the surfaces of the equine carpus were determined to be proximal to distal, except in a small area over the accessory carpal bone where a state of anisotropism existed. In an immobilized carpus, direction of a surgical incision was not as important as it was in a mobile carpus, in which th...
Alm H, Neumann H, Torner H, Tomek W, Wollenhaupt K, Kanitz W, Becker F.Equine oocytes were collected by follicle aspiration in vivo or by dissection of material obtained from an abattoir, and the ultrastructure, protein phosphorylation and mRNA status of the oocytes were evaluated. Electron microscopy studies indicated that the nucleus had a smooth membrane in oocytes with a compact cumulus, whereas the nuclear membrane was undulated in all other groups. Oocytes with compact cumuli had only a few microvilli, whereas those with expanded cumuli had more microvilli. There were only small numbers of cortical granules close to the oolemma in oocytes with compact cumul...
Bienert-Zeit A, Gietz C, Staszyk C, Kietzmann M, Stahl J, Ohnesorge B.To monitor concentrations of sulfadimidine in the paranasal sinus mucosa (PSM) of unsedated horses following IV administration of trimethoprim-sulfadimidine via in vivo microdialysis. Methods: 10 healthy adult horses. Methods: Concentric microdialysis probes were implanted into the subepithelial layers of the frontal sinus mucosa of standing sedated horses. Four hours after implantation, trimethoprim-sulfadimidine (30 mg/kg) was administered IV every 24 hours for 2 days; dialysate and plasma samples were collected at intervals during that 48-hour period and analyzed for concentrations of sulfa...
Morandi F, Frank N, Avenell J, Daniel GB.99mTc-mebrofenin is used in humans and small animals to assess hepatic function. This study was undertaken to measure hepatic clearance of 99mTc-mebrofenin in healthy horses and to determine whether feed deprivation and increased serum total bilirubin (TBIL) concentration alter 99mTc-mebrofenin clearance. Plasma clearance of 99mTc-mebrofenin was determirned in 7 healthy horses at 0, 48, and 96 hours of feed withholding. Serum TBIL and nonesterified fatty acid (NEFA) concentrations were measured every 24 hours. 99mTc-mebrofenin (4.16 +/- 0.62 mCi, mean +/- SD) was injected into a jugular vein, ...
Manohar M, Thurmon JC, Tranquilli WJ, Shawley RV, Froelich P.A technique was developed for long-term catheterization of the coronary sinus in calves and ponies. A catheter with a 10 to 12 cm-long stiff segment was implanted via right lateral thoracotomy. Catheters were kept patent up to 10 weeks after the surgical procedure. At that time, location of the catheter tip was confirmed both by determining oxygen tension of the anaerobically sampled blood and by radiography. Base-line values of oxygen venous blood of non-anesthetized calves and ponies are reported.
Zaleska M, Anusz K, Winnicka A, Kita J.Twelve horses, all of them 10 years old, were vaccinated intramuscularly on 0 and 28 days of the experiment with inactivated vaccine containing only antigens of A-equi-2/Miami/63. Another three unvaccinated horses, each at the age of 10 years, were the negative control group. One, ten-year-old horse was vaccinated with commercial inactivated vaccine containing both antigens of A-equi-2/Miami/63 as well as A-equi-1/Praha/56 as positive control. Three horses were challenged intranasally with homotypic strain of Miami/63, while six other were challenged with heterotypic strains--three with Suffol...
Dunlop CI, Hodgson DS, Chapman PL, Grandy JL, Waldron RD.The purpose of this study was to compare the thermodilution technique for estimation of cardiac output with the indocyanine green dye dilution technique at flows between 10 and 39 L/min in halothane-anesthetized horses. The estimation of area of dye dilution cardiac output curves was made by using the fore-'n-aft (FA) triangle method. This shorthand technique was compared with logarithmic exponential extrapolation and summation (extrapolated area), using 64 cardiac output curves. Then, 256 simultaneous thermodilution measurements were compared with dye dilution measurements calculated by use o...
Evans JW, Stanfield J, Hoffman LS, Slaussen C.Testes were obtained from 70 colts and stallions and were pooled according to age (4 months to 23 years) to determine the relationship of age to LH/hCG receptor kinetics. The receptor concentration (Rt) increased from 0.069 x 10(-11) M/mg crude membrane fraction (CMF) for the 4-14-month pools to 0.464 x 10(-11) M for the 2-3-year-old pools. A 10-fold increase in testicular size also occurred, and so the total number of receptors per testis was significantly increased. A further increase to 1.237 x 10(-11) M/mg CMF was observed for stallions older than 5 years. No differences in binding affinit...
Pfeiffer CJ, Murray MJ, Fainter L.The granular columnar epithelial cell of the equine dorsal large colon has been studied by transmission electron microscopy and X-ray microanalysis. Particular attention was focused on nuclear bodies commonly observed as central clusters of spherical, electron-dense inclusions within the nucleus. Ultrastructural morphology as well as X-ray microanalysis spectra reveal great similarity between colonic nuclear bodies and the numerous small granules of the apical cytoplasm in these epithelial cells. X-ray spectra of these cells were distinct from those of goblet cell mucous granules and mast cell...
