Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Xuan X, Chahan B, Huang X, Yokoyama N, Makala LH, Igarashi I, Fujisaki K, Maruyama S, Sakai T, Mikami T.The prevalence of equine piroplasmosis in Xinjiang province, China, was examined by enzyme-linked immunosorbent assays (ELISAs). A total of 70 serum samples were taken from horses pastured on three farms in western Xinjiang, and examined for diagnosis of equine Babesia equi (B. equi) infection and B. caballi infection by ELISAs using recombinant equi merozoite antigen 1 (EMA-1) and recombinant P48 antigen, respectively. Of the 70 samples, 28 (40.0%) and 17 (24.3%) samples were positive for B. equi infection and B. caballi infection, respectively. In addition, 11 (15.7%) samples were positive f...
Tidwell SA, Schneider RK, Ragle CA, Weil AB, Richter MC.To report complications observed using a hydro-pool recovery system after general anesthesia in horses. Methods: Retrospective study. Methods: Sixty horses. Methods: Retrospective review of the medical records and quality of recovery from anesthesia of 60 horses that had surgical or diagnostic procedures under general anesthesia. Results: Mean total anesthesia time was 182 minutes (range, 25 to 390 minutes). Mean time in the hydro-pool was 108 minutes (range, 20 to 270 minutes). One horse that had bilateral rear limb extensor weakness while recovering in a padded recovery stall was moved to th...
Mateos-Trigos G, Evans RJ, Heath MF.Horses show susceptibility to platelet-related disorders. Equine platelets differ from human platelets in some of their responses, so information available about human platelets must be validated in the horse. Aggregation of platelets by ADP involves both P2Y(1) and P2Y(12) receptors on the platelet surface. We have compared the effect of the P2Y(12) antagonist, AR-C67085, on equine and human platelets in vitro using turbidimetric aggregometry to measure the rate and final extent of aggregation. Aggregation profiles, concentration-response curves and pA(2) values show that the rate of aggregat...
Guan F, Uboh CE, Soma LR, Luo Y, Li R, Birks EK, Teleis D, Rudy JA, Tsang DS.Clenbuterol (CBL) is a potent beta(2)-adrenoceptor agonist used for the management of respiratory disorders in the horse. The detection and quantification of CBL can pose a problem due to its potency, the relatively low dose administered to the horse, its slow clearance and low plasma concentrations. Thus, a sensitive method for the quantification and confirmation of CBL in racehorses is required to study its distribution and elimination. A sensitive and fast method was developed for quantification and confirmation of the presence of CBL in equine plasma, urine and tissue samples. The method i...
Coles GC.It is suggested that the major factor in avoiding the development of anthelmintic resistance is the percentage of worms that do not encounter the anthelmintics (worms in refugia). This in turn is determined by the numbers of larvae on pasture, the percentage of animals treated and whether any stages in the host can avoid the action of anthelmintic. To maintain anthelmintic efficacy the percentage of worms in refugia must be sufficiently large. In cattle, this should involve treating only first-year animals and using a different pasture each year for calves. For sheep, only animals that have to...
Budras KD, Schiel C, Mülling CK, Patan B.The preparation of hard tissues such as the equine hoof horn for electron microscopic examination is very difficult. In particular the penetration of fixatives and chemicals used during fixation and embedding is a problem. The objective of this study was to find and implement an alternative method enabling the preparation of high-quality thin sections of hoof horn and other hard tissue, which maintains the hard tissue ultrastructure and can be used for immuno-labeling. Compared to commonly used fixation and embedding techniques, the preparation of thin sections from untreated material method s...
Li QC, Mabrouk PA.This paper reports the first report of rapid, reversible direct electron transfer between a redox protein, specifically, horse myoglobin, and a solid electrode substrate in nonaqueous media and the spectroscopic (UV-vis, fluorescence, and resonance Raman) characterization of the relevant redox forms of myoglobin (Mb) in dimethyl sulfoxide (DMSO). In DMSO, the heme active site of metmyoglobin (metMb) appears to remain six-coordinate high-spin, binding water weakly. Changes in the UV-fluorescence spectra for metMb in DMSO indicate that the protein secondary structure has been perturbed and sugge...
Chateau H, Degueurce C, Jerbi H, Crevier-Denoix N, Pourcelot P, Audigié F, Pasqui-Boutard V, Denoix JM.The objective of this study was to assess the effects of asymmetric placement of the foot on the three-dimensional motions of the interphalangeal joints. Four isolated forelimbs were used. Trihedrons, made of three axes fitted with reflective markers, were screwed into each phalanx. They allowed to establish a local frame associated with each bone and thus to define the spatial orientation of the phalanges. The limbs were then placed under a power press, and subjected to compression with gradually increasing force (from 500 to 6 000 N). The procedure was performed in neutral position and with ...
The Journal of parasitologyAugust 29, 2002
Volume 88, Issue 4 810-811 doi: 10.1645/0022-3395(2002)088[0810:GIACAR]2.0.CO;2
Labruna MB, Ribeiro AF, Cruz MV, Camargo LM, Camargo EP.During a survey of ticks on horses in November 2000, at the University of São Paulo farm in Pirassununga county, São Paulo, Brazil, 1 gynandromorph of Amblyomma cajennense was collected from a naturally infested horse. In another survey on dogs in March 2001, in the urban area of Monte Negro, Rondônia, Brazil, a gynandromorph of Rhipicephalus sanguineus was collected from a naturally infested dog. Both specimens are described and classified as perfect bipartite protogynanders.
The Journal of parasitologyAugust 29, 2002
Volume 88, Issue 4 678-683 doi: 10.1645/0022-3395(2002)088[0678:OSOPEF]2.0.CO;2
Chapman MR, French DD, Taylor HW, Klei TR.The development of acquired resistance to cyathostome challenge after 1 season's exposure to a cyathostome-contaminated pasture was investigated using 17 parasite-naive ponies, which were 2-3 yr of age. These were divided into 3 groups: 1 to graze a cyathostome-contaminated pasture for 4 mo (exposed ponies), 1 to graze a "clean" pasture not previously grazed by parasitized animals (nonexposed ponies), and 1 group to remain in the barn under helminth-free conditions (parasite-free ponies). After pasture exposure all ponies were housed in stalls in the barn dewormed with ivermectin (200 microgra...
Kim I, Cohen ND, Carroll RJ.The authors describe a method for assessing and characterizing effect heterogeneity related to a matching covariate in case-control studies, using an example from veterinary medicine. Data are from a case-control study conducted in Texas during 1997-1998 of 498 pairs of horses with colic and their controls. Horses were matched by veterinarian and by month of examination. The number of matched pairs of cases and controls varied by veterinarian. The authors demonstrate that there is effect heterogeneity related to this characteristic (i.e., cluster size of veterinarians) for the association of c...
Dzierzecka M, Kita J.The investigations aimed to establish the reliability of the chosen serological tests designed for the diagnosis of Lyme borreliosis in horses. The investigations were carried out in five Horse Breeding Centres (OHK). Statistical analysis methods were used to determine sample size for particular centres: Krasne (Kr)--49, Łack (Ł)--21, Walewice (W)--111, BogusŁawice (B)--17, Kozienice (K)--61. The experimental material comprised the chosen horses from which blood samples were collected in order to obtain sera. The test used for indirect immunofluorescence assay (IFA No 75941, Bio-Mérieux) i...
Heldens JG, Weststrate MW, van den Hoven R.Using the area under the curve (AUC) concept as is commonly used in pharmaceutical bioequivalence studies, the bioequivalence of three equine influenza vaccines was demonstrated. A retrospective analysis was performed using this technique on data generated in three trials in which each of the three vaccines had been used. In total, data from 63 pony and horse foals were used. The AUC of the single radial hemolysis (SRH) titres against Influenza A/equi-1/Prague/56 (Pr/56), A/equi-2/Newmarket-1/93, and A/equi-2/Suffolk/89 (Suf/89) were calculated for each horse. It was concluded that calculation...
This report summarizes West Nile virus (WNV) surveillance data reported to CDC through ArboNET and verified by states and other jurisdictions as of July 23, 2002. During the reporting week of July 17-23, nine human cases of WNV were reported from two states (Louisiana and Mississippi). During the same period, WNV infections were reported in 202 dead crows, 48 other dead birds, 13 horses, and 69 mosquito pools.
Blanchar TL, Brinsko SP, Rigby SL.A tendency for deslorelin implants to suppress subsequent follicular growth and delay return to estrus following induced ovulation has been documented in nonlactating mares. To investigate this phenomenon in lactating mares, 22 broodmares in southeast Texas were administered either deslorelin or hCG to induce ovulation in the first postpartum estrus during February and March 2001. Mares were teased daily and examined twice weekly (Tuesdays and Thursdays) by transrectal ultrasonography. When a follicle >35 mm diameter was detected on Tuesday, mares were treated with either 2,500 U hCG admini...
Hartel PG, Summer JD, Hill JL, Collins JV, Entry JA, Segars WI.Several genotypic methods have been developed for determining the host origin of fecal bacteria in contaminated waters. Some of these methods rely on a host origin database to identify environmental isolates. It is not well understood to what degree these host origin isolates are geographically variable (i.e., cosmopolitan or endemic). This is important because a geographically limited host origin database may or may not be universally applicable. The objective of our study was to use one genotypic method, ribotyping, to determine the geographic variability of the fecal bacterium, Escherichia ...
Larsen MM, Lendal S, Chriél M, Olsen SN, Bjørn H.A questionnaire survey regarding endoparasite control practices in Danish horse herds was carried out in 1995. The participating veterinarians and herd owners were sampled using convenience and purposive sampling. In the analysis of risk factors for development of a high endoparasitic burden (> 200 eggs per gram faeces) 903 horses were sampled and the analysis of the efficiency of a single anthelmintic treatment was based on 605 horses. The following factors had a significant effect on the endoparasitic burden: herd type, age of the horses, use of pasture rotation, anthelmintic treatment of ho...
Long MT, Mines MT, Knowles DP, Tanhauser SM, Dame JB, Cutler TJ, MacKay RJ, Sellon DC.Sarcocystis neurona was isolated from the blood of a 5-month-old Arabian foal with severe combined immunodeficiency. The foal had been inoculated approximately 3 weeks previously with 5 x 10(5) sporocysts that were isolated from the intestines of an opossum and identified by restriction enzyme analysis of PCR products as S. neurona. The isolate obtained from the blood of this foal was characterized by genetic, serologic, and morphologic methods and identified as S. neurona (WSU1). This represents the first time that S. neurona has been isolated from any tissue after experimental infection of a...
Wagner IP, Hood DM.To evaluate the effect of prolonged water exposure on tissue mass and solutes of outer and inner layers of the stratum medium, sole, frog, and the stratum medium (SMZA) zona alba layer of horses' hooves. SPECIMEN POPULATION: 10 hooves from 10 horses without foot abnormalities. Methods: Hoof wall tissue specimens were obtained and immersed for 10 days in distilled deionized water. Serial changes in mass were recorded during the immersion period. Subsequently, osmolarity and Na+, K, Cl-, and protein concentrations of the immersion solution were quantified. Results: Fully cornified outer hoof wal...
Holcombe SJ, Berney C, Cornelisse CJ, Derksen FJ, Robinson NE.To determine the effect of a commercially available nasal strip on airway mechanics in exercising horses. Methods: 6 horses (5 Standardbreds and 1 Thoroughbred). Methods: Horses exercised on a treadmill at speeds corresponding to 100 and 120% of maximal heart rate with and without application of a commercially available nasal strip. Concurrently, tracheal pressures, airflow, and heart rate were measured. Peak inspiratory and expiratory tracheal pressures, airflow, respiratory frequency, and tidal volume were recorded. Inspiratory and expiratory airway resistances were calculated by dividing pe...
Smith D, Hamblin A, Edington N.Antisera to activated equine endothelial cells, which detected surface molecules of 116 kD, 97 kD, 42 kD and 38 kD, were made to investigate the role of endothelial adhesion molecules in equid herpes virus 1 infection. These putative adhesion molecules could be induced by 17-beta oestradiol, chorionic gonadotrophin, or IL-2, as well as by LPS and PWM. In an in vitro flow system, using equine veins or arteries, equid herpesvirus 1 in leucocytes was only transferred to infect endothelial cells if both leucocytes and endothelial cells expressed these surface molecules. Blocking of the membrane mo...
Lichtenfels JR, Gibbons LM, Krecek RC.Terminology for common names for the Tribe Cyathostominea (cyathostomins), and disease caused by the nematodes (cyathostominosis), were recommended to replace the previously used names cyathostomes and cyathostomosis, which are ambiguous, inaccurate or synonymous, by the Third Internal Workshop on the Systematics of Cyathostominea of Horses, held in Stresa, Italy, 28 August 2001. The progress by this international working group at three workshops is reviewed briefly and a list of publications is provided. Included are an annotated checklist by genus and species of 93 species level names and th...
Audigié F, Pourcelot P, Degueurce C, Geiger D, Denoix JM.The aim of this paper is to present a method allowing the identification of the lame limb in trotting horses. Using a 3-D kinematic analysis system, 13 sound and 25 lame horses fitted with 4 skin markers placed on the dorsal midline of their trunk were recorded while trotting on a track in the conditions of the routine lameness examination. The vertical displacements of the trunk markers underwent Fourier analysis. Results indicated that these displacements could be represented using only the first and second harmonics. From these two harmonics, indices were then developed. The sensitivity of ...
Grooters AM, Whittington A, Lopez MK, Boroughs MN, Roy AF.The purpose of this study was to evaluate the effects of sample handling, storage, and culture techniques on the isolation of Pythium insidiosum from infected equine tissues. Tissue and kunker samples obtained immediately posteuthanasia from a horse with subcutaneous pythiosis were used to assess the effects of sample type (kunkers vs. tissues), media type (selective vs. nonselective), storage technique, and storage time on P. insidiosum isolation rate. Overall, isolation rates were higher from fresh kunkers (94.6%) and stored kunkers (76.4%) than from fresh tissues (8.3%) or stored tissues (4...
Kleiboeker SB, Schommer SK, Johnson PJ, Ehlers B, Turnquist SE, Boucher M, Kreeger JM.Over a period of 6 years, antemortem and postmortem examinations were performed on a number of donkeys suffering from respiratory disease. For many cases, initial diagnostic efforts failed to identify an etiology consistent with the pathologic findings. However, retrospective examination of these cases using consensus primer polymerase chain reaction, designed to recognize herpesviruses from all 3 subfamilies of the Herpesviridae, amplified a fragment of the highly conserved herpesvirus DNA polymerase gene from a number of these animals. Two novel herpesviruses, herein designated asinine herpe...
Kreeger JM, Templer A, Tumquist SE, Bailey KL, Johnson PJ, Wilson DA.Paranasal meningioma was diagnosed in a 5-year-old Appaloosa gelding. The mass occupied the right maxillary, frontal, and sphenopalatine sinuses but did not invade the calvarium. The diagnosis was based on histologic evaluation, positive immunohistochemical staining for vimentin and cytokeratin, and ultrastructural features including the presence of interdigitating spindle cells with numerous desmosomes.
Kriz NG, Rose RJ.To assess the repeatability of commonly employed transthoracic echocardiographic measurements in standing horses. Methods: Thirteen healthy 3- to 4-year-old fit Standardbred geldings with a mean weight of 411 (SEM +/- 10) kg were studied. The horses' environment, feeding and management regimens were standardised. All measurements were performed by the same investigator at the same time every day for three consecutive days. Methods: Standard transthoracic measurements were made on all horses. Each measurement was performed over three consecutive cardiac cycles on 1 day and all measurements were...
Li L, Maboni G, Lack A, Gomez DE.Nontuberculous mycobacteria (NTM) infections are increasing in human and veterinary medicine. Although horses were initially thought to be resistant to NTM infection, reports of horses suffering from gastrointestinal, respiratory, and reproductive diseases associated with NTM have increased in the last few decades. The aim of this literature review is to summarize the mycobacteria species found in horses, describe clinical manifestations, diagnostic and treatment approaches, and public health concerns of NTM infection in horses. Clinical manifestations of NTM in horses include pulmonary diseas...
Silver M, Comline RS.Mares and fetuses with indwelling catheters in the umbilical and uterine vessels have been used to monitor transplacental blood gas tensions, pH, O2 affinities and the concentration of various metabolites in fetal and maternal blood during late gestation. Measurements of umbilical and uterine blood flows and arterio-venous differences enabled the uptake of O2 and glucose by the fetus and the uterus to be estimated. The present findings are compared with those from other species in comparable conditions.
Harman RM, Rajesh A, Van de Walle GR.Treatment of skin wounds is a high priority in veterinary medicine because healthy uncompromised skin is essential for the well-being of horses. Stem cells and other biologic therapies offer benefits by reducing the need for surgical procedures and conventional antibiotics. Evidence from in vitro studies and small in vivo trials supports the use of equine stem cells and biologics for the treatment of acute and chronic cutaneous wounds. Larger clinical trials are warranted to better evaluate the regenerative and immunological responses to these treatments. Additionally, delivery methods and t...
Dosi MCM, Riggs CM, May J, Lee A, Cillan-Garcia E, Pagan J, McGorum BC.There is a paucity of data relating to the vitamin D status of racehorses. We hypothesised that the management of racehorses in Hong Kong (HK) predisposes to low vitamin D status unless they receive dietary supplementation. Serum concentrations of 25-hydroxyvitamin D2 (25OHD2), 25-hydroxyvitamin D3 (25OHD3) and total 25-hydroxyvitamin D (total 25OHD) for 79 non-grazing HK racehorses were compared with those for 22 racehorses training in the United Kingdom (UK) that grazed for ≥1 h/d, and for which published data exists. A nested group of 41 HK horses was sampled twice to determine the effect...
Hart LT, Braymer HD, Larson AD, Broussard EA.Equine infectious anemia (EIA) antigen extracted from the spleen of horses infected with EIA virus was purified by pH treatment, (NH4)2SO4 fractionation and affinity chromatography. The homogeneity of the antigen was indicated by sedimentation rate and sedimentation equilibrium experiments. A S20,w of 0.51 was determined and a molecular weight of 7600 was calculated from sedimentation equilibrium analysis. The amino acid composition of the pure antigen indicated the antigen is an acidic protein. Employing radical immunodiffusion (RID) and pure antigen a method for quantitating antigen content ...
Lagounova M, MacNicol JL, Weese JS, Pearson W.Synbiotics are often provided to horses receiving antibiotics to protect against microbiome disturbances, despite a lack of evidence for efficacy. The purpose of this study was to evaluate the effect of a synbiotic product in horses receiving antibiotics. Sixteen actively racing Standardbred horses were randomly allocated (four-way crossover) to one of four groups: antibiotics (10 days; AB), synbiotics (28 days; PROBIOPlusTM; PBP), PBP + AB, or Control. The fecal microbiome was investigated using 16S rRNA sequencing, and fecal dry matter (DM; %), pH, and scores (FS; 0-9) were measured. Data we...
McLean AK, Falt T, Abdelfattah EM, Middlebrooks B, Gretler S, Spier S, Turoff D, Navas Gonzalez FJ, Knych HK.Recent approval of transdermal flunixin meglumine (FM) (Banamine®) in cattle has opened the door for the drug's potential application in other species. Transdermal FM could provide a safe and effective form of pain relief in donkeys. In order to evaluate the pharmacokinetics and effects of FM on anti-inflammatory biomarkers in donkeys, a three-way crossover study design was employed. In total, 6 healthy donkeys were administered transdermal (TD) FM at a dosage of 3.3 mg/kg, and oral (PO) and intravenous (IV) doses of 1.1 mg/kg body weight. Blood samples were collected over 96 h to determine t...
Bello K, Lorch G, Kim K, Toribio RE, Yan L, Xie Z, Hill K, Phelps M.Additional efficacious immunomodulatory treatment is needed for the management of immune-mediated disease in horses. Mycophenolate mofetil (MMF) is an immunosuppressive drug that warrants assessment as a viable therapeutic agent for horses. Objective: To evaluate the pharmacokinetics (PK) of multiple-day oral dosing of MMF in healthy horses and to determine the tolerability of this dosing regimen. Methods: Six healthy Standardbred mares. Methods: Horses received MMF 10 mg/kg PO q12h for 7 days in the fed state. Serial sampling was performed over 12 hours on Days 1 and 7 with trough sampl...
Etemadi F, Tabatabaei Naeini A, Aminlari M.Minerals play vital roles in physiologic processes. Calcium, phosphorus and magnesium are common minerals. Secretion, absorption and homeostasis of these minerals are affected by associations between the active vitamin D and parathyroid hormone (PTH). The aim of this study was to assess concentrations of vitamin D, PTH and minerals, such as calcium, phosphorus and magnesium in horse sera, as well as associations of these values with lameness in horses. In the references, the reasons for lameness can be deficiency and imbalance of minerals, and clinical observations also confirm this and there ...
Vergara-Hernandez FB, Nielsen BD, Kottwitz JJ, Panek CL, Robison CI, Paris BL, Welsh TH, Bradbery AN, Leatherwood JL, Colbath AC.To determine the single-dose pharmacokinetics of clodronate disodium (CLO) in juvenile sheep and the plasma protein binding (PPB) of CLO in juvenile sheep and horses. Methods: 11 juvenile crossbred sheep (252 ± 6 days) for the pharmacokinetic study. Three juvenile crossbred sheep (281 ± 4 days) and 3 juvenile Quarter Horses (599 ± 25 days) for PPB analysis. Methods: CLO concentrations were determined using liquid chromatography-mass spectrometry. Pharmacokinetic parameters were calculated by noncompartmental analysis from plasma samples obtained at 0, 0.5, 1, 3, 6, 12, 24, 48, and 72 hours ...
Pearson GB, Papa B, Mosaddegh A, Cooper H, Aprea M, Pigott J, Altier C, Cazer CL, Reesink HL.To investigate (1) variables associated with the likelihood of obtaining a positive culture, (2) commonly isolated microorganisms, and (3) antimicrobial resistance patterns of isolates from horses with presumptive synovial sepsis. Methods: Synovial fluid, synovium, and bone samples from equine cases with presumptive synovial sepsis submitted to the Cornell University Animal Health Diagnostic Center from 2000 to 2020 for microbial culture and antimicrobial sensitivity testing. Methods: Univariable and multivariable analyses were performed to determine the effect of variables on the likelihood o...
Bordin C, Raspa F, Harris P, Ellis AD, Roggero A, Palestrini C, Bergero D, Valle E.The application of hay feeding devices, such as the use of hay nets or slow feeders, can help with the management of weight in ponies; however, there is still a lack of knowledge regarding their effect on equine posture. Therefore, the aim of the study was to assess the effect of different feeding devices on the posture of ponies using morphometric analysis. Two different breed types, Shetland type (SH, n = 5) versus Welsh Cob type (WC, n = 4), were fed the same forage in four different ways: on the ground (G), using a fully filled haynet (HF), using a partially filled haynet (HL) and...
Costa LRR, Swiderski C, Palm C, Aleman M.To investigate if hepatitis A virus cell receptor 1/kidney injury molecule 1 (HAVCR1/KIM1) in urine is detectable concurrently with increases in serum creatinine concentrations in horses receiving a recommended dose of phenylbutazone (PBZ) for 7 days. Methods: Preliminary study. Methods: Ten clinically healthy horses with normal physical examination and laboratory work were randomly assigned to PBZ or placebo groups (5 each). The PBZ group received PBZ at 4.4 mg/kg mixed with corn syrup orally every 12 hours. The placebo group received corn syrup orally every 12 hours. Both groups were tre...
Silvestri R.A macromethod and a semimicromethod were developed to measure erythrocyte acetylcholinesterase activity in cattle, sheep, goats, horses, dogs, and swine, and to measure plasma cholinesterase activity in horses, dogs, and swine. Comparison of the 2 methods with erythrocytes of sheep, cattle, goats, and horses indicated both methods gave similar results. They can be done in a shorter time and are more sensitive than Michel's method. Normal deltapH values per minutes, with standard deviations for blood cholinesterase activity of animals of different ages, sexes, breeds, and species, were: 0.76 +/...
Jirgensons B, de Haas GH.Conformation of porcine, bovine, and equine pancreatic phospholipases A2 (EC 3.1.1.4) and their zymogens was studied by the circular dichroism (CD) probe in the far and near ultraviolet spectral zones.
All these phospholipases and their zymogens displayed CD curves suggesting the presence of moderate amounts of α-helical conformation. However, on the basis of known primary structure and recent X-ray structural analysis of prophospholipase A2 crystals (Drenth, J., Enzing, C.M., Kalk, K.H. and Vessies, J.C.A. (1976) Nature 264, 373–377), it has to be concluded that the positive CD band cen...
Jones RH, Hayes RO, Potter HW, Francy DB.A survey of biting flies in the southwestern United States resulted in the recovery of 34 species as they attacked equines. The geographic distribution of each species at 15 sites and the abundance of attacking flies were used to determine that 22 species commonly attack equines. Culicoides variipennis (Coquillett) was the most common species collected; it was recovered at 12 sites and comprised the highest percentage (29.8%) of the total survey catch for all species collected. The next 2 most common species were Psorophora columbiae (Dyar & Knab) and Aedes vexans (Meigen). C. variipennis was ...
Benson GJ, Hartsfield SM, Smetzer DL, Thurmon JC.Succinylcholine chloride, administered to horses anesthetized with halothane in oxygen and mechanically ventilated, caused slight but significant (P less than 0.01) increases in heart rate. Significant alteration in mean arterial blood pressure did not occur, and there were clinically insignificant increases in serum K+ and C1- concentration. Cardiac dysrhythmia and myoglobinuria did not occur. Thus, effects of halothane anesthesia and mechanical ventilation prevented cardiac dysrhythmia and hypertension and greatly reduced the tachycardia generally associated with siccinylcholine administrati...
Graham EF, Crabo BG, Pace MM.From the studies cited it was concluded that short and long term preservation of stallion semen has encountered major obstacles. Fertilizing capacity of extended or extended and cooled spermatozoa has been impaired. With the hydrogen ion extenders, the fertility was depressed either with or without glycerol when the semen was inseminated immediately after extension. With the cream-gel extender, fertility was not impaired when inseminated immediately after extension, but was impaired after storage at 5 C for 24 hr or in the presence of glycerol. The fertilizing capacity of extended frozen sperm...
Poskus E, Zakin MM, Fernámdez HN, Paladini AC.Peptide fragments, obtained from equine growth hormone by cyanogen bromide cleavage and further chemical treatment, were isolated and identified. Their immunological reactivities were tested by hemagglutination and complement fixation methods using rabbit antisera against native hormone. Antigenic determinants were detected in the fragments comprising amino acid sequences 5-72 and 73-123, this last one being predominant. Fragment 124-178 had very low reactivity. Nitration of peptide 73-123 did not modify its immunological properties,but oxidation diminished them. Comparison of the antigenicity...
Duvivier DH, Votion D, Vandenput S, Art T, Lekeux P.To determine the effects of the dry powder inhalation (DPI) of ipratropium bromide (ipratropium) on the airways of health horses and the dose-response curve in horses suffering from chronic obstructive pulmonary disease (COPD) by means of pulmonary function tests, five healthy horses were first studied. Ipratropium (2400 micrograms ipratropium horse-1) was contained in gelatine capsules and administered using a dry powder device connected to an adapted face mask. Pulmonary function tests were recorded before inhalation and 15 and 60 min after inhalation. No modification of pulmonary function w...
Kronfeld DS.The current estimate of LD50, 21.5 mg/kg BW, for lasalocid in horses is based on an analysis of 8 data from 4 horses that died at dose levels of 15, 21, 22 and 26 mg/kg. This analysis neglected 14 data from another 6 horses that survived at dose levels of 5, 10,14, 18, 19, 25, 29 and 50 mg/kg, and so was biased by selection of data. An examination of all the data indicates they are insufficient to determine the LD50. In contrast, the whole data set suggests a lowest toxic dose of 15 mg/kg, although this estimate was based on only 1 affected animal in 8 tests from 5 to 15 mg/kg in an unbalanced...
Mirck MH.A form of strongyle infection in young horses and ponies, observed during the period from November to May, is described. Large numbers of larvae of Cyathostominae in the fourth or early fifth stage of development are found to be present in the (often watery) faeces. This excretion of larvae is not affected by treatment with anthelmintics. A large number of these patients die from the sequelae of verminous enteritis.
Chaney KP.Congenital anomalies of the urinary tract in horses may be difficult to diagnose and treat. Presenting complaints are variable and include weight loss, depression, dysuria, hematuria, and mild colic. Although the most severe abnormalities are diagnosed in the neonate, some diseases, such as ectopic ureter(s), may be identified in older horses. In human medicine, the fetus is examined in the prenatal period for evidence of urinary tract dysfunction, but this is not yet common practice in equine medicine. As a result, urinary tract anomalies are diagnosed after birth using a wide variety of diag...
Labens R, Khairuddin NH, Murray M, Jermyn K, Ahmad RS.To assess fracture gap reduction and stability of linear vs triangular 4.5-mm lag screw repair of experimental, uniarticular, and complete forelimb proximal phalanx (P1) fractures. Methods: Experimental. Methods: Fourteen equine cadaver limbs/horses. Methods: Simulated fractures were repaired with 2 lag screws under 4-Nm insertion torque (linear repair). Computed tomography (CT) imaging was performed with the leg unloaded and loaded to forces generated while walking. The fracture repair was revised to include 3 lag screws placed with the same insertion torque (triangular repair) prior to CT. T...
Blickwede M, Dolz G, Herrero MV, Tomlinson SM, Salman M.Serum samples were collected from domestic horses in 4 different regions of Costa Rica to detect antibodies against vesicular stomatitis viruses, serotypes New Jersey (VSV-NJ) and Indiana (VSV-IN). A total of 214 samples were tested by the virus neutralization test. The sampling regions were identified as low North Pacific dry area (1), low Middle Atlantic humid area (2), low South Pacific humid area (3), and the highlands (4). In region 1, 97.1% of horses were positive for VSV-NJ and 16.5% were positive for VSV-IN. The mean antibody titer and its standard deviation after logarithmic transform...
Jordan KV, Drouillard JS, Douthit TL, Lattimer JM.Eight cecally cannulated Quarter Horses were used in a replicated 4 × 4 Latin square experiment conducted in four 14-d periods to determine effects of sodium caseinate (casein) on hindgut fermentation and fiber digestion. During each period, horses were assigned to one of four treatments consisting of control (water; CON), 0.125 g casein/kg BW (LOW), 0.25 g casein/kg BW (MED), or 0.5 g casein/kg BW (HI). Casein was solubilized in 800 mL water and dosed directly into the cecum at 0700 and 1900 hours using a metal dosing syringe. Smooth Bromegrass hay (CP 8.50%), water, and salt were provided a...
Millichamp NJ.Horses with ocular trauma frequently present as emergency cases. This article provides a succinct review of various adnexal and globe injury issues. Accurate case assessment, management, prognosis, and follow-up considerations are presented.
Guedes A, Knych H, Hood D.Laminitis is a painful disease for which adequate pain management remains a challenging and largely unmet medical need. Objective: To investigate plasma concentrations, analgesic and physiological effects of 2 doses of tramadol in horses with chronic laminitis. Methods: Nonrandomised trial. Methods: Four horses with naturally occurring chronic laminitis received 5 mg/kg bwt and then 10 mg/kg bwt tramadol orally every 12 h for one week with a one-week washout between. Noninvasive arterial blood pressure, heart and respiratory rates, intestinal sounds and forelimb off-loading frequency were ...
Aleman M, Davis E, Knych H, Guedes A, Smith F, Madigan JE.Intrathecal lidocaine hydrochloride under general anesthesia has been used as an alternative method of euthanasia in equids. Carnivore, scavenger, and even human consumption of horse meat from carcasses have been anecdotally reported in rural areas after this method of euthanasia. The presence of drug residues in horse meat has not been investigated. Objective: To investigate if drug residues are found in horse tissues and determine their concentrations. Methods: Of 11 horses requiring euthanasia for medical reasons. Methods: Prospective descriptive study. Horses were anesthetized with total I...
