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.
Choi YH, Landim-Alvarenga FC, Seidel GE, Squires EL.Experiments were conducted to study effects of macromolecules on stallion sperm capacitation and fertilization as determined by penetration of bovine zona-free and equine partially zona-removed oocytes. Stallion sperm were capacitated in TYH medium (modified Krebs-Ringer bicarbonate) supplemented with either 1 mg/mL of polyvinylalcohol (PVA) or 4 mg/mL of BSA. Capacitation was induced with 8 bromoadenosine cyclic monophosphate (8BrcAMP; 0.5 mM) alone or in combination with 0.1 microM of ionomycin. Intraspecies gametes were co-incubated in TYH/PVA or TYH/BSA for 18 to 20 h. For zona-free bovine...
Frank N, Sojka JE, Patterson BW, Wood KV, Bonham CC, Latour MA.To compare kinetics of the metabolism of very-low-density lipoprotein (VLDL) apolipoprotein B (apoB) before and after thyroidectomy in mares. Methods: 5 healthy adult mares. Methods: Thyroidectomy was performed in euthyroid mares. Kinetics of VLDL apoB metabolism were measured before and after thyroidectomy by use of a bolus IV injection of 5,5,5-2H3 (98%) leucine (5 mg/kg) and subsequent isolation of labeled amino acid from plasma and VLDL. Labeled leucine was quantified by use of gas chromatography-mass spectrometry. Production rate (PR), delay time, and fractional catabolic rate (FCR) were ...
Witonsky S, Gogal RM, Buechner-Maxwell V, Ahmed SA.To determine whether immune function can be accurately assessed in blood samples obtained from horses and refrigerated overnight and whether a nonradioactive lymphocyte proliferation assay can be used to evaluate samples obtained from horses. Methods: 224 blood samples from 28 clinically normal adult horses. Methods: Heparinized blood samples were collected. Each sample was divided into 2 equal aliquots. One aliquot was refrigerated overnight to simulate overnight shipping of blood samples, and the other aliquot was evaluated on the day of blood collection. Lymphocytes were isolated and enumer...
Rowe EL, White NA, Buechner-Maxwell V, Robertson JL, Ward DL.To identify apoptosis in equine intestines and determine whether apoptosis is associated with gastrointestinal tract disease or a specific tissue layer of intestine. Methods: 38 horses that underwent surgery or were euthanatized for small or large intestine obstruction, strangulation, or distension and 9 control horses euthanatized for reasons other than gastrointestinal tract disease or systemic disease. Methods: Specimens were collected at surgery from intestine involved in the primary lesion and distant to the primary lesion site or at necropsy from several sites including the primary lesio...
Boyde A.This review presents findings made in studies of large mammalian bones, especially from racehorse training experiments (2-8 years old, third metacarpal, tarsal) and human autopsy orthopaedic femoral implant retrievals and other human biopsy and autopsy cases. Samples were cleaned to analyse mineralized matrix in three dimensions, or poly methyl-methacrylate embedded and micromilled to delete topography and study the superficial c. 0.5-microm two-dimensional section using quantitative backscattered electron imaging. With experimental implant studies in rabbits, observations were also made in vi...
Frias AF, Mársico F, Gómez de Segura IA, Nascimento PR, Nascimento A, Soares JH, Almosny NR.To characterize responses to different doses of propofol in horses pre-medicated with xylazine. Methods: Six adult horses (five females and one male). Methods: Each horse was anaesthetized four times with either ketamine or propofol in random order at 1-week intervals. Horses were pre-medicated with xylazine (1.1 mg kg-1 IV over a minute), and 5 minutes later anaesthesia was induced with either ketamine (2.2 mg kg-1 IV) or propofol (1, 2 and 4 mg kg-1 IV; low, medium and high doses, respectively). Data were collected continuously (electrocardiogram) or after xylazine administration and at 5, 1...
Szeredi L, Aupperle H, Steiger K.Formalin-fixed, paraffin wax-embedded fetal membranes from 76 cases of equine abortion were examined immunohistochemically for equine herpesvirus (EHV)-1 antigen. Of the 76 cases, 11 had been proved EHV-1-positive by diagnostic methods applied to the aborted fetuses (viral isolation in tissue culture, or immunohistochemical examination, or both). Of the 11 fetal membranes from the virus-positive animals, five gave positive results on immunohistochemical examination, and three on in-situ hybridization; the positive signals were detected in trophoblastic cells and occasionally in monocytes and e...
Lopez AM, Hines MT, Palmer GH, Knowles DP, Alperin DC, Hines SA.Rhodococcus equi remains one of the most important pathogens of early life in horses, yet conventional vaccines to prevent rhodococcal pneumonia have not been successful. DNA vaccination offers an alternative to conventional vaccines with specific advantages for immunization of neonates. We developed a DNA vaccine expressing the vapA gene (pVR1055vapA) that induced an anamnestic response characterized by virulence associated protein A (VapA)-specific IgG antibodies in sera and bronchoalveolar lavage fluid (BALF) as well as VapA-specific proliferation of pulmonary lymphocytes when tested in adu...
Kriegshäuser G, Wutz G, Lea S, Stuart D, Skern T, Kuechler E.Mouse monoclonal antibodies (mAbs) were employed to select neutralization escape mutants of equine rhinitis A virus (ERAV). Amino acid changes in the ERAV mutants resulting in resistance to neutralization were identified in capsid protein VP1 at Lys-114, Pro-240 and Thr-241. Although the changes were located in different parts of the polypeptide chain, these mutants exhibited cross-resistance against all four mAbs employed, indicating that these residues contribute to a single immunogenic site. To explain this result, we constructed a model of the three-dimensional structure of the ERAV capsid...
Böhnel H, Wernery U, Gessler F.Botulism is caused by different types of Clostridium botulinum, a soil bacterium. Equine grass sickness (equine dysautonomia) is suspected of being a clinical form of this disease. On a stud where this disease occurred twice within 8 months, grass and soil samples and necropsy specimens of one horse were tested for the presence of bacterial forms and toxin of C. botulinum. Different types and type mixtures (A-E) of C. botulinum and botulinum neurotoxin were found. For the first time, it has been shown that green grass blades contain botulinum toxin. The results support the hypothesis that equi...
Lafortuna CL, Saibene F, Albertini M, Clement MG.Horses display remarkable aerobic capabilities, attaining during muscular exercise a maximal rate of oxygen consumption about 30-fold higher than the resting value, and 2.5-fold higher than that of other mammals of similar body mass. Under these circumstances an enormous mechanical burden is expected to impinge on the equine respiratory pump and regulatory mechanisms aiming to minimize this load may play an important role in determining the adequacy of the respiratory system to the metabolic requirements. The behaviour of the respiratory system has been investigated in horses at rest and durin...
Gehlen H, Bubeck K, Stadler P.In 12 healthy warmblood horses (six trained and six untrained) the pulmonary wedge pressure and heart frequency was measured at rest and during a standardised exercise test on a treadmill. The mean pulmonary wedge pressure at rest was 14.53 +/- 2.36 mmHg. There was no significant difference in pulmonary wedge pressure either at rest or during exercise between trained and untrained horses. During walking (1.8 m/s) the mean pulmonary wedge pressure was 19.62 +/- 4.03 mmHg, during trotting (4 und 5 m/s) it was between 22.38 +/- 3.92 mmHg and 25.28 +/- 3.7 mmHg. During canter (6 m/s) and gallop (8...
Bartmann CP, Stief B, Schoon HA.Transendoscopic thermal preparation techniques like laser- or electrosurgery have proved to be most reliable for minimal invasive intrauterine surgery during operative hysteroscopy in mares. To determine the effect of Nd:YAG laser surgery on the endometrium and the complete uterine wall compared with electrosurgery, standard lesions were obtained by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and Nd:YAG laser surgery (contact, bare fibre, 25 Watt, exposure time four seconds, non contact, 80 Watt, exposure time four seconds) in five healthy mares on days d 0, 7, 14,...
Orsini JA, Haddock M, Stine L, Sullivan EK, Rabuffo TS, Smith G.To determine the odds of moderate or severe gastric ulceration in racehorses treated with various antiulcer medications. Methods: Unmatched case-control study. Methods: 798 horses in active race training (252 Thoroughbreds and 546 Standardbreds). Only horses that had been receiving a single antiulcer medication or no antiulcer medication for at least 2 weeks prior to examination were included. Methods: Gastroscopy was performed on each horse by a single individual who was not aware of the horses' antiulcer treatments, and severity of gastric ulceration was scored. Signalment and medication his...
Breuhaus BA.To determine whether ingestion of fescue seed infected with the endophyte Neotyphodium coenophialum would alter thyroid function in adult horses. Methods: Original study. Methods: 4 adult mares that were not pregnant and 6 adult geldings. Methods: Thyrotropin releasing hormone stimulation tests were performed while horses received a standard diet and after infected seed (2.3 kg/d [5 lb/d]) had been fed for 1 and 2 months. Serum prolactin concentrations were measured to verify endophyte absorption. Results: Serum prolactin concentrations indicated that at least 8 of 10 horses absorbed the endop...
Brown NA, Kawcak CE, McIlwraith CW, Pandy MG.Articular injuries in athletic horses are associated with large forces from ground impact and from muscular contraction. To accurately and noninvasively predict muscle and joint contact forces, a detailed model of musculoskeletal geometry and muscle architecture is required. Moreover, muscle architectural data can increase our understanding of the relationship between muscle structure and function in the equine distal forelimb. Muscle architectural data were collected from seven limbs obtained from five thoroughbred and thoroughbred-cross horses. Muscle belly rest length, tendon rest length, m...
Galli C, Lagutina I, Crotti G, Colleoni S, Turini P, Ponderato N, Duchi R, Lazzari G.Several animal species, including sheep, mice, cattle, goats, rabbits, cats, pigs and, more recently, mules have been reproduced by somatic cell cloning, with the offspring being a genetic copy of the animal donor of the nuclear material used for transfer into an enucleated oocyte. Here we use this technology to clone an adult horse and show that it is possible to establish a viable, full-term pregnancy in which the surrogate mother is also the nuclear donor. The cloned offspring is therefore genetically identical to the mare who carried it, challenging the idea that maternal immunological rec...
McGuire TC, Leib SR, Mealey RH, Fraser DG, Prieur DJ.Control of a naturally occurring lentivirus, equine infectious anemia virus (EIAV), occurs in most infected horses and involves MHC class I-restricted, virus-specific CTL. Two minimal 12-aa epitopes, Env-RW12 and Gag-GW12, were evaluated for presentation by target cells from horses with an equine lymphocyte Ag-A1 (ELA-A1) haplotype. Fifteen of 15 presented Env-RW12 to CTL, whereas 11 of 15 presented Gag-GW12. To determine whether these epitopes were presented by different molecules, MHC class I genes were identified in cDNA clones from Arabian horse A2152, which presented both epitopes. This h...
Tremoleda JL, Stout TA, Lagutina I, Lazzari G, Bevers MM, Colenbrander B, Galli C.Blastocyst formation rates during horse embryo in vitro production (IVP) are disappointing, and embryos that blastulate in culture fail to produce the characteristic and vital glycoprotein capsule. The aim of this study was to evaluate the impact of IVP on horse embryo development and capsule formation. IVP embryos were produced by intracytoplasmic sperm injection of in vitro matured oocytes and either culture in synthetic oviduct fluid (SOF) or temporary transfer to the oviduct of a ewe. Control embryos were flushed from the uterus of mares 6-9 days after ovulation. Embryo morphology was eval...
Meiswinkel R, Paweska JT.Between February and May 1998, approximately 100 horses died of African horse sickness (AHS) in the cooler, mountainous, central region of South Africa. On 14 affected farms, 156,875 Culicoides of 27 species were captured. C. imicola Kieffer, hitherto considered the only field vector for AHS virus (AHSV), constituted <1% of the total Culicoides captured, and was not found on 29% of the farms. In contrast, 65% of the Culicoides were C. bolitinos Meiswinkel, and was found on all farms. Five isolations of AHSV were made from C. bolitinos, and none from 18 other species of Culicoides (including C....
Newton JR, Wood JL, Chanter N.A matched case control study was used to determine infections and other factors associated with clinically apparent respiratory disease in young racehorses in training in the UK. A total of 170 cases, defined as horses with sudden onset coughing, nasal discharge or pyrexia, were identified and matched to 632 non-affected controls by trainer and time period. Factors examined included age, sex, time since entry into the training yard, time since last race and different infections including tracheal and nasopharyngeal (NP) bacteria and viruses. Multivariable conditional logistic regression (CLR) ...
Dongus H, Beelitz P, Schöl H.The female reproductive system of Thelazia lacrymalis (Nematoda: Thelaziidae) was investigated by light and scanning electron microscopy (SEM) with regard to the developmental stages and the stage deposited by the gravid nematode. Female T. lacrymalis have a didelphic and opisthodelphic type of reproductive system with paired ovaries, oviducts and uteri and a single vagina and vulva. Round and spindle-shaped primary oocytes are documented within the ovaries and oviducts, respectively. The distal part of each uterus provides a fertilization chamber filled with spermatozoa, followed by a sphinct...
Blazyczek I, Hamann H, Ohnesorge B, Deegen E, Distl O.The objective of the present study was to analyse the importance of the influences of sex, inbreeding coefficient, proportion of genes of the original breeds and the additive genetic contribution to the occurrence of guttural pouch tympany in foals belonging to German Warmblood breeds. Foals affected by guttural pouch tympany were ascertained in the Clinic of Horses, School of Veterinary Medicine Hannover. This data set comprised 22 German Warmblood foals with guttural pouch tympany, which were patients of the Clinic for Horses between 1994 and 2001. Information on the pedigrees and all availa...
Martínez AC, Hernández M, Rivera L, Recio P, García-Sacristán A, Benedito S.To investigate the effect of acetylcholine (ACh) on horse deep dorsal penile vein and to characterize the muscarinic receptor subtypes involved in this response. Methods: Vein rings were mounted in an organ bath chamber, and the isometric tension was recorded. Results: In phenylephrine-contracted veins, ACh (1 nM to 1 microM) induced endothelium-dependent relaxation. The muscarinic receptor antagonist, atropine, produced parallel rightward shifts of the ACh response curves (pA2 = 10.04; pK(B) = 9.98). Carbachol (10 nM to 100 microM) also evoked relaxation in the vein segments, but showed a low...
Foreman JH, Bayly WM, Grant BD, Gollnick PD.Ten healthy sedentary male Thoroughbreds with previous race training experience were studied for 14 weeks. Horses were trained for 9 weeks, using a program designed after those used commonly in the United States. Horses were trained conventionally by slow trotting (250 m/min) for 2 weeks and galloping (390 to 450 m/min) for 4 weeks, followed by 3 weeks of galloping (440 to 480 m/min) and intermittent sprinting exercises (breezes) at distances between 600 and 1,000 m (900 to 950 m/min). The horses were then pasture rested for 5 weeks. A standardized exercise test (SET) involving an 800-m gallop...
Blue MG.In a retrospective study of selected cases, abdominal colic in 30 horses was attributed to enterolith obstructions of the large intestine. Obstructions caused by "true" enteroliths were confined to horses more than four years old. Prominent clinical features were recurrent mild abdominal pain, inappetance, gaseous distension and minimal intestinal motility. The various aspects of the clinical syndrome, including diagnostic problems and clinical management, are discussed. Most obstructing enteroliths were found near the beginning of the small colon and most horses contained only a single major ...
Ponthier J, Franck T, Detilleux J, Mottart E, Serteyn D, Deleuze S.Despite improvement of techniques, semen of 20% of stallions remains unfreezable. Recent studies focused on the impact of reactive oxygen species and oxidant enzymes on semen characteristics. Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after cell lysis. It is responsible for the formation of hypochlorous acid, a strong oxidant agent, which could damage spermatozoa. The aim of this study was to determine the relation between MPO concentration and characteristics of frozen semen from stallions. Thirty-five straws from different s...
Gronert GA, Fung DL, Jones JH, Shafer SL, Hildebrand SV, Disbrow EA.We investigated the effects of body size on the pharmacokinetics and pharmacodynamics of the renally cleared muscle relaxant metocurine. We hypothesized that pharmacokinetics of the drug would change allometrically in proportion to physiological time [infinity Mb0.25, where Mb is body mass] and that pharmacodynamics would be independent of size because of the highly conserved structure of the acetylcholine receptor. Metocurine effects during general anesthesia were examined in 17 rats, 8 cats, 6 dogs, 5 pigs, 7 sheep, and 12 horses. Allometric analysis demonstrated size dependence for pharmaco...
Nagel C, Aurich J, Palm F, Aurich C.Heart rate (HR) is an important parameter of fetal well-being. In horses, HR and heart rate variability (HRV) can be determined by fetomaternal electrocardiography (ECG) from mid-pregnancy to foaling. Normal values for physiological parameters in larger breeds are often used as reference values in ponies. However, HR increases with decreasing size of the animal and in ponies is higher than in warmblood horses. It is not known if fetal HR is affected by breed and if values obtained in larger breeds can be used to assess Shetland fetuses. We have determined fetomaternal beat-to-beat (RR) interva...
Everett JB, Schumacher J, Doherty TJ, Black RA, Amelse LL, Krawczel P, Coetzee JF, Whitlock BK.OBJECTIVE To determine the effects of stacked wedge pads and chains applied to the forefeet of Tennessee Walking Horses on behavioral and biochemical indicators of pain, stress, and inflamation. ANIMALS 20 Tennessee Walking Horses. PROCEDURES Horses were randomly assigned to 2 treatment groups: keg shoes (control; n = 10) or stacked wedge pads and exercise with chains (10). Ten days before treatment application, an accelerometer was attached at the left metatarsus of each horse to record daily activity. Horses were exercised for 20 minutes daily, beginning on day -7. On day 0, exercise ceased,...
Benton HP, Esquivel AV, Rice AD, Giri SN.Pirfenidone is under investigation as an anti-inflammatory and anti-fibrotic agent in several organs including lung. Since important features of arthritic conditions include inflammation and long-term damage to articular cartilage, we have investigated whether PD can suppress chondrocyte responses to bacterial lipopolysaccharide (LPS) and interleukin 1 (IL-1); modulators that induce a cascade of inflammatory responses that lead to articular joint tissue damage. PD (0 - 5microM) showed no effect on cell number or viability when incubated with high density primary equine chondrocyte cultures for...
Rech R, Barros C.This article focuses on the gross examination of the brain and spinal cord and outlines the main lesions and neuroanatomic location related to neurologic diseases in horses.
Tull TM, Woodie JB, Ruggles AJ, Reimer JR, Embertson RM, Hopper SA, Bramlage LR.Few studies have evaluated the athletic prognosis of foals affected by gastrocnemius disruption. Objective: To examine the diagnosis and management of gastrocnemius disruption in Thoroughbred (TB) foals, determine short-term survival rate and assess future racing performance. The hypothesis was that Thoroughbred foals with gastrocnemius disruption are able to perform as racehorses comparably to their age matched maternal siblings. Methods: The medical records of foals diagnosed with gastrocnemius muscle disruption were reviewed. Information on training and racing was acquired from published wo...
Inoue Y, Matsui A, Asai Y, Aoki F, Yoshimoto K, Matsui T, Yano H.We studied the response of biochemical markers of bone metabolism to exercise intensity in horses. Four horses were walked on a mechanical walker for one week (pre-exercise). Then they performed low-speed exercise on a high-speed treadmill in the first week and medium-speed exercise in the second week and high-speed exercise in the third week of training. We measured two indices of bone resorption, serum hydroxyproline concentration and the urinary deoxypyridinoline/creatinine ratio, and serum osteocalcin (OC) concentration as an index of bone formation. Both indices of bone resorption gradual...
Wilkes EJA, Cowling A, Woodgate RG, Hughes KJ.Faecal egg counts (FEC) are used widely for monitoring of parasite infection in animals, treatment decision-making and estimation of anthelmintic efficacy. When a single count or sample mean is used as a point estimate of the expectation of the egg distribution over some time interval, the variability in the egg density is not accounted for. Although variability, including quantifying sources, of egg count data has been described, the spatiotemporal distribution of nematode eggs in faeces is not well understood. We believe that statistical inference about the mean egg count for treatment decis...
Derisoud E, Auclair-Ronzaud J, Palmer E, Robles M, Chavatte-Palmer P.Although puberty can occur as early as 14-15months of age, depending on breed and use, the reproductive career of mares may continue to advanced ages. Once mares are used as broodmares, they will usually produce foals once a year until they become unfertile, and their productivity can be enhanced and/or prolonged through embryo technologies. There is a general consensus that old mares are less fertile, but maternal age and parity are confounding factors because nulliparous mares are usually younger and older mares are multiparous in most studies. This review shows that age critically affects c...
Poth MKM, McKemie DS, Traynham M, Kass PH, Knych HK.The metabolism and pharmacokinetics of intravenous (i.v.) morphine in the horse have been described; however, administration of therapeutic doses has also been associated with neuroexcitation and adverse gastrointestinal effects. In this study, we hypothesized that oral administration would lead to comparable concentrations of morphine and its presumed active metabolite, morphine 6-glucuronide (M6G) without the adverse effects associated with i.v. administration. Eight horses were administered a single i.v. dose of 0.2 mg/kg morphine and oral doses of 0.2, 0.6, and 0.8 mg/kg of morphine in a...
Grubbs ST, Amodie D, Rulli D, Wulster-Radcliffe M, Reinemeyer C, Yazwinski T, Tucker C, Hutchens D, Smith L, Patterson D.The safety and efficacy of 2% moxidectin/12.5% praziquantel oral gel administered at a rate of 0.4 mg moxidectin and 2.5 mg praziquantel/kg was studied in client-owned horses under field use conditions. Four hundred horses (300 treated with moxidectin/praziquantel oral gel and 100 treated with vehicle) were enrolled, feces were collected, and eggs were counted. Investigators as well as horse owners were masked to treatment assignment. No adverse reactions to treatment were observed in any horses. Moxidectin/praziquantel gel reduced Anoplocephala spp by more than 99% and provided a significant ...
Jenson PW, Gaughan EM, Lillich JD, Bryant JE.To determine clinical findings in and outcome of horses with fractures of the second or fourth metacarpal or metatarsal bone that underwent segmental ostectomy, leaving the proximal and distal portions of the bone undisturbed. Methods: Retrospective case series. Methods: 17 horses. Methods: Medical records were reviewed, and information on signalment, affected bone, lesion type, surgical procedure, amount of bone removed, and surgical and postsurgical complications was obtained. Follow-up information was obtained through telephone conversations with owners, trainers, and referring veterinarian...
Kuwamura M, Iwaki M, Yamate J, Kotani T, Sakuma S, Yamashita A.A 9-year-old male horse showed emaciation, weakness and trembling and was euthanatized. Histopathological examinations revealed loss, swelling and chromatolysis of motor neurons throughout the spinal ventral horns, axonal degeneration of the ventral spinal roots. Eosinophilic cytoplasmic inclusions were distributed in degenerated spinal ventral neurons. Ultrastructurally, the inclusions consisted of aggregations of granular dense material and a few vesicles. They reacted positively with polyclonal antibody against ubiquitin. The present case was diagnosed as equine motor neuron disease, which ...
Lam K, Pumphrey SA.Uveal cysts can lead to undesirable behaviors and poor performance in horses. Transcorneal laser ablation has been proposed as a safe and effective treatment for uveal cysts suspected of causing behavioral changes but outcomes have been reported in only a small number of horses. In this retrospective study, records were identified for horses who had undergone transcorneal cyst ablation using a diode laser. Information was collected regarding signalment, behavioral or performance issues reported prior to the procedure, and complications. Owners were contacted to provide follow-up information re...
Di Salvo A, Busechian S, Zappulla F, Marchesi MC, Pieramati C, Orvieto S, Boveri M, Predieri PG, Rueca F, Della Rocca G.A new formulation of omeprazole in gastro-resistant granules was tested with regard to its pharmacokinetics and tolerability. Twenty-four horses were randomly divided into three groups (8 horses/group) and treated, according a parallel study design, as follows: Group A untreated (control group), Group B received 4 mg/kg of omeprazole, and Group C received 12 mg/kg of omeprazole, both of which were treated orally once a day for 90 days. Blood samples, taken from Group B subjects during the 1st and the 29th day of treatment at pre-established time points, were used to determine the concentrat...
Newcombe JR, Wilsher S, Cuervo-Arango J.Mares are seasonally polyoestrous breeders. Therefore, the first ovulation of the season, following winter anoestrus, is the only cycle in which mares ovulate without the presence of an old CL from the previous cycle. The objective of this study was to compare the length of oestrous behaviour, and plasma progesterone concentrations during the early post-ovulatory period between mares after the first and second ovulation of the breeding season. Overall, 38 mares and 167 oestrous periods were used in the study. From those, 11 mares were used during the first and subsequent oestrous period to mea...
Sebastian PS, Benitez-Ibalo AP, Flores FS, Debárbora VN, Martinez EI, Thompson CS, Mangold AJ.To investigate the presence of Theileria equi in an endemic area of equine piroplasmosis 42 horses (Equus caballus) from Corrientes City, Argentina were sampled. Eighty-one percent (34 blood samples) of the analyzed horses were tested positive to the presence of piroplasmid 18S rDNA. All these samples could be identified as T. equi by amplifying the specific EMA-1 (merozoite antigen 1) gene of this species. Phylogenetic analysis of an obtained 18S rDNA complete sequence from one strain resulted in the identification of this sample as T. equi sensu stricto (genotype A). This study presents the ...
Tsujimura K, Yamada M, Nagata S, Yamanaka T, Nemoto M, Kondo T, Kurosawa M, Matsumura T.We investigated the pharmacokinetics of penciclovir after oral administration of its prodrug famciclovir to horses. Following an oral dose of famciclovir at 20 mg/kg, maximum plasma concentrations of penciclovir occurred between 0.75 and 1.5 hr (mean 0.94 + or - 0.38 hr) after dosing and were in the range 2.22 to 3.56 microg/ml (mean 2.87 + or - 0.61 microg/ml). The concentrations of penciclovir declined in a biphasic manner after the peak concentration was attained. The mean half-life of the rapid elimination phase was 1.73 + or - 0.34 hr whereas that of the slow elimination phase was 34.34 +...
Lopez-Navarro G, Trigo-Tavera FJ, Rodriguez-Monterde A, Gutierrez-Ospina G, Arechavaleta-Velasco M, Schumacher J, Schumacher J.Proximal suspensory desmitis (PSD) is a common cause of lameness in the pelvic limb, but could also affect the thoracic limb of competing and non-competing horses. Most horses diagnosed with PSD in a thoracic limb respond to rest followed by controlled exercise, but in a small percentage of affected horses, lameness persists. In one study, four horses chronically lame because of PSD in a thoracic limb became sound after neurectomy of the deep branch of the lateral palmar nerve (DBLPaN), which innervates the proximal aspect of the suspensory ligament (SL; Guasco et al., 2013). Whether neurectom...
Prieto D, Hernandez M, Rivera L, Ordaz E, Garcia-Sacristan A.The aim of the present study was to determine the distribution and density of catecholaminergic nerve fibres and cells in the equine ureter by using immunohistochemical techniques to localise the enzyme tyrosine-hydroxylase (TH). TH-immunoreactive (TH-IR) nerve fibres entered the wall of the ureter as adventitial nerve trunks accompanying the blood vessels. These trunks repeatedly branched as they coursed through the muscular layer towards the epithelium, forming muscular, perivascular and subepithelial nerve plexuses. TH-IR nerve fibres were especially numerous in the pelvic and intravesical ...
Lund JR, Ketover HR, Hetzel S, Waller K, Brounts SH.To evaluate with CT the characteristics of brain tissue disruption and skull damage in cadaveric heads of adult horses caused by each of 6 firearm-ammunition combinations applied at a novel anatomic aiming point. Methods: 53 equine cadaveric heads. Methods: Heads placed to simulate that of a standing horse were shot with 1 of 6 firearm-ammunition combinations applied at an aiming point along the external sagittal crest of the head where the 2 temporalis muscles form an inverted V. Firearm-ammunition combinations investigated included a .22-caliber long rifle pistol firing a 40-grain, plated le...
Wilson KAT, Raisis AL, Drynan EA, Lester GD, Hosgood GL.To determine agreement between invasive blood pressures measured in three peripheral arteries in anaesthetized horses undergoing elective surgery. Methods: Prospective balanced incomplete block design. Methods: A total of 18 client-owned horses. Methods: Invasive blood pressure (IBP) was measured simultaneously in one of the following three combinations: 1) transverse facial and facial artery; 2) transverse facial and metatarsal artery; and 3) facial and metatarsal artery. The agreement in blood pressure measured for each combination was performed in six horses. At each sample time, systolic (...