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.
Issel CJ, Adams WV.In 1975, a survey was conducted in East Baton Rouge Parish, Louisiana, to determine the prevalence of equine infectious anemia. Using the agar gel immunodiffusion test, 94 of 1,398 horses (6.7%) were found to be infected. Infection rates were especially high in areas where clinical cases of equine infectious anemia had been diagnosed. Clinical signs compatible with the disease were noted in 1 of the 94 seropositive horses. The sample set of 1,398 horses represented 22% of the census population obtained during the 1971 Venezuelan equine encephalomyelitis vaccination campaign.
Coffman JR, Johnson JH, Tritschler LG, Garner HE, Scrutchfield WL.Fourteen horses (7 treated with orgotein and 7 treated with a placebo) with navicular disease were studied on a double blind basis. All 14 horses had clinical and radiographic evidence of navicular disease. Orgotein and the placebo were administered by juxtabursal injection. Of the 7 orgotein-treated horses, 3 responded but none of the 7 placebo-treated horses responded. The difference was statistically significant (P less than 0.05).
Halliwell RE, Fleischman JB, Mackay-Smith M, Beech J, Gunson DE.Twenty-five horses with chronic pulmonary disease were skin tested with allergenic extracts of 24 molds, 4 thermophilic actinomyces, barn dust, hay dust, soya-bean mill dust, and grain mill dust. The results were compared with those obtained on 25 normal horses. Between the 2 groups of horses, there was a highly significant difference in positive skin test results at 30 minutes and 4 hours.
Wentink GH.The dynamics of the hind limbs of the horse and dog at walk are compared. The kinematics were studied by electromyography of animals walking on a moving belt, and by cinephotography in horses walking on the ground and in dogs walking on a moving belt and on the ground.
This study reveals that: 1) the retraction of the hoof or foot relative to the hip at the end of the support phase is less in the horse than in the dog; 2) the change in the sense of the movements of the hind limb segments at the end of the support phase and at the beginning of the swing phase occurs earlier in the horse (55â...
Yamauchi S.The horse fetal adrenal gland was shown to begin to increase in weight from about the end of the 4th month of pregnancy when the fetus has a crown-rump length of about 20 cm. Growth then proceeds steadily to term but, in contrast to the adult horse, the medulla remains thicker than the cortex throughout fetal life. The cortex also becomes established around 20 cm crown-rump length and at the same time the glomerular and fascicular zones become distinguishable. In contrast the reticular zone is not differentiated until around 50 cm crown-rump length. In the fetal adrenal cortex, the fascicular ...
Moss GE, Estergreen VL, Becker SR, Grant BD.[1,2,6,7-3H]Progesterone was injected into the uterine artery of umbilical vein of 4 pregnant Ponies to determine whether 5 alpha-pregnane-3,20-dione (DHP), 20 alpha-hydroxy-5 alpha-pregnan-3-one (20 alpha-ol), and 3 beta-hydroxy-5 alpha-pregnan-20-one (3 beta-ol) are produced by the placenta, fetus, or mare during late gestation. Plasma samples were collected from indwelling catheters in the uterine artery and vein and the umbilical artery and vein at frequent intervals until 6 h after isotope injection. The plasma samples were extracted with organic solvents and the respective pregnanes were...
Sembrat RF, Di Stazio J, Stremple JF.This study was conducted to determine the feasibility of using alert, conscious ponies as a model for septic shock in man. Ten ponies were given 0.7-5 X 10(9) organisms/kg of body weight of live E coli intravenously over one hour. All ponies died and exhibited signs of low cardiac output septic shock. significant decreases were found in cardiac index to 3.15 +/- 0.1 liters/min/m2 (P less than 0.05), white blood cell count to 1,930 +/- 100 cells/m3 (P less than 0.05), preterminal blood glucose to 75 +/- 5 mg/dl (P less than 0.05), PaO2 to 75.7 +/- 5.7 mm Hg (P less than 0.05), and pH to 7.15 +/...
Gygax AP, Ganjam VK, Kenney RM.The surprisingly rapid rate of uterine involution detected is consistent with a high rate of conception as the first post-partum heat. Furthermore, many of the immediately post-partum features have attained the pregravid state by the end of the first post-partum oestrus and virtually all by the second post-partum oestrus. There was no specific cause detected for the higher rate of early embryonic death associated with conception at the foal heat.
Burns SJ, Irvine CH, Amoss MS.This study was undertaken to determine if fertility could be improved by increasing the interval from foaling to breeding. Forty-two mares, not bred during normal post-partum oestrus, were injected with a prostaglandin analogue on Day 6 or 7 following ovulation. Mares were mated artifically with antibiotic-treated semen during the resulting oestrus and, if necessary, for the following 4 cycles. Their fertility was compared, by cycles/pregnancy and rate of fetal loss, to mares bred by the same methods on 86 normal post-partum oestrous periods. The interval from foaling to the onset of breeding ...
Klevjer-Anderson P, Cheevers WP, Crawford TB.Equine dermal fibroblasts persistently infected with equine infectious anemia virus (EIAV) show no alterations in cell morphology or growth kinetics when compared to uninfected cells. The percentage of cells immunofluorescent positive for viral proteins fluctuated, depending upon the stage of the cell cycle, while production of extracellular virus was uniform throughout the cell cycle, increasing only as the cell number increased. This was shown in log versus stationary phase cultures as well as in cultures synchronized by sterum starvation. The establishment of productive infection did not re...
Snyder DA, Turner DD, Miller KF, Garcia MC, Ginther OJ.Observations of follicular and gonadotrophic changes were conducted on 14 Pony mares for 31-day periods beginning at the penultimate (second last) ovulation and at the last ovulation of the season. There were no main effects or interaction of day or period on the numbers of small follicles (less than 20 mm). Concentrations of FSH, numbers of large follicles (greater than 20 mm), and oestrous behaviour each showed an effect of day (P less than 0.01), but no effect of period. Concentrations of LH and diameter of the largest follicle each showed an interaction (P less than 0.01) between day and p...
Seamans KW, Harms PG, Atkins DT, Fleeger JL.Blood samples were collected from eight mares for ten days before and two days following parturition. Progesterone, 5 alpha-dihydroprogesterone and hydroxy-5 alpha-pregnanones were extracted from serum, separated by Sephadex LH-20 column chromatography and quantitated by radioimmunoassay. Progesterone levels ranged from 8.5 to 4.1 ng/ml among mares with normal parturition and decreased to 1.2 ng/ml after parturition. One mare with a retained placenta maintained the prepartal levels of progesterone into the postpartum period. 5 alpha-dihydroprogesterone increased to a level of 133 ng/ml at 80 h...
Crandell RA, Drysdale S, Stein TL.The clinical and immunological response of ponies exposed to a bovine herpesvirus isolate and equine herpesvirus 1 were compared. Each virus was inoculated into two ponies by the intranasal route. One uninoculated pony was used with each group as a contact control. The four inoculated ponies developed a mild rhinitis with an increase in rectal temperature. Virus was recovered from nasal secretions collected from the four inoculated and one contact pony. All ponies developed a serum neutralizing antibody to each virus. The data show that the two viruses are similar.
Kendrick JW, Stevenson W.A band of 23 pregnant mares on a Thoroughbred breeding farm all had serum virus-neutralizing antibody titres to equine herpesvirus 1 (EHV-1). Antibody was not transferred to their foals in utero. All foals received antibody from colostrum and developed antibody titres similar to their dams. The serum virus-neutralizing antibody titres were observed in 10 of these foals for 1 year. Decay of passive immunity occurred at the rate of 3.25 two-fold dilutions in 100 days and reached zero at the mean time of 180 days. The foals were exposed to EHV-1 twice. Foals with a geometric mean titre of 1 : 25 ...
Hurtgen JP, Ganjam VK.Endometrial biopsy or endometrial biopsy and uterine culture taken on Day 4 after oestrus induced lysis of the corpus luteum (CL), resulting in a sharp decline in serum progesterone concentration and shortened the interoestrous interval in 8/12 and 32/33 oestrous cycles, respectively, during 2 experiments. Cervical dilatation 4 days after oestrus shortened the interoestrus interval in 5/10 and 0/5 oestrous cycles. Endometrial biopsy and culture on Days 1 and 3 after oestrus also induced CL lysis during 4 of 7 cycles. Total oestrogen (oestrone plus oestradiol) concentrations increased at the on...
Thomson GW, McCready R, Sanford E, Gagnon A.In the foaling season of 1977, five vaccinated horses in a Standardbred breeding stable were affected with herpesvirus myeloencephalitis. Respiratory and abortigenic forms also occurred in other individuals on the premises. Equine herpesvirus type 1 was isolated from the brain of one case of myeloencephalitis and from lungs of two aborted fetuses. Twelve of 16 horses demonstrated fourfold or greater increases in titres to equine herpesvirus type 1.
Vernon MW, Strauss S, Simonelli M, Zavy MT, Sharp DC.The binding of prostaglandin (PG) F-2 alpha to corpora lutea (CL) from pregnant and non-pregnant Pony mares was examined. Studies of the rates of association and dissociation indicated that [3H]PGF was bound specifically and reversibly to a luteal cell membrane preparation (MP) that was isolated by high speed (100,000 g) ultracentrifugation. Various PGs and PG metabolites displaced [3H]PGF from the receptors in the following decreasing order: PGF-2 alpha greater than 13, 14-dihydro-PGF-2 alpha = 13,14-dihydro-15-keto PGF-2 alpha greater than PGD-2 greater than PGF-1 alpha = PGE-2 greater than ...
Vandeplassche M, Henry M, Coryn M.Oestrogen and progesterone concentrations in blood and follicular fluid and blood levels of LH were determined in 426 mares at different stages of the oestrous cycle. Mature follicles occur at all stages of the cycle; they ovulate readily in early metoestrus, occasionally in late metoestrus and very rarely in dioestrus. Maturation of a mid-cycle follicle is associated with intermediate levels of LH, which are less than those found during oestrus. This lower level of LH together with a high level of progesterone are probably responsible for the failure of ovulation and regression of most of the...
Stewart F, Allen WR.Gonadotrophin-receptor binding studies involving the use of 125I-labelled highly purified FSH and LH have shown that equine gonadal tissues possess similar numbers of specific FSH and LH receptors per cell as the gonadal tissues of other mammals. However, while rat, cow and pig gonadal tissues were shown to bind as much 125I-labelled PMSG as 125I-labelled LH on a molar basis, the equivalent equine tissues bound only less than or equal to 4% as much of the labelled PMSG as LH. Competitive binding studies involving the use of radioreceptor assay techniques have further demonstrated that the smal...
Palmer E.The use of photoperiod, progestagen, prostaglandin and hCG treatments was investigated to obtain mating of mares at predetermined times. The objectives were: (1) synchronization of oestrus at an early time of the year, (2) simplification of treatment schedules by use of vaginal sponges, and (3) use of several controlled cycles by successive synchronization. The following conclusions were reached. First, after a 16 h photoperiod was applied beginning on 25 November, hormonal synchronization of oestrus and ovulation followed by cyclicity were obtained on 1 February; i.e. 2 months of light are es...
Amann RP, Thompson DL, Squires EL, Pickett BW.Extragonadal reserves totalled 89 X 10(9) spermatozoa for 5--16-year-old sexually rested stallions and 60 X 10(9) for 2--4-year-olds. Regardless of age, the cauda epididymidis contained 62% of the total reserves and the vas deferens, including the ampulla, contained 7% of the total reserves of spermatozoa. The caput plus corpus epididymidis from 5--16-year-old stallions (N = 41) contained 14.9 X 10(9) spermatozoa per side as compared (P less than 0.01) to 8.5 X 10(9) for 2--4-year olds (N = 30). Frequency of ejaculation did not influence the number of spermatozoa found in caput plus corpus epi...
Bostedt H, Lehmann B.By means of clinical and analytical procedures (enzyme immuno assay for progesterone with microtiterplate method) the ovarian activity from 27 mares was tested over a period of several weeks. The measurement of the progesterone level to determine the time of ovulation was proved as suitable in the period of 1-2 days after ovulation. In normocyclic mares (n = 17) a different development of the progesterone profile was detected, so that an insufficient development of the corpus luteum (35%) could be considered. By means of continuous measurement of progesterone (> or = 30 days) six of ten mares ...
Brook D, Schmidt GR.A case of pre-renal azotaemia is described in a 12 year old pony resulting from oesophageal obstruction of 8 days duration. Blood urea nitrogen, creatinine, calcium, inorganic phosphate, sodium, potassium, chloride and bicarbonate concentrations were monitored throughout the recovery period. After relief of the obstruction normal blood concentrations were quickly restored.
Zerpa H, Bailey SR, Berhane Y, Elliott J.Alpha-adrenoceptors mediate contractile responses in equine digital veins (EDVs) and arteries. Vascular smooth muscle alpha(1)-adrenoceptor subtypes have been implicated in a number of conditions, such as acute equine laminitis, and are therapeutic targets for the treatment of this condition. Digital veins, rather than arteries, were investigated in the present study because they have been specifically implicated in the pathophysiology of acute laminitis. The order of potency of a series of alpha(1)-adrenoceptor-selective agonists and antagonists was determined in isolated rings of EDVs under ...
Harris PA.An outbreak of muscle stiffness and poor performance among 59 thoroughbreds at a Newmarket flat racing yard was investigated between the beginning of May and the end of June 1986. Over a third of the horses showed signs of muscular stiffness, and 38 had, at one or more of the sampling times, creatine kinase (CK) activities above 200 iu/litre and, or, aspartate aminotransferase (AST) activities above 300 iu/litre when they were sampled six to eight hours after exercise. The following season, at a similar time and stage of training, only four of 39 horses sampled had CK activities between 200 an...
Meghoufel A, Cloutier G, Crevier-Denoix N, de Guise JA.The fiber bundle density (FBD) calculated from ultrasound B-scan images of the equine superficial digital flexor tendon (SDFT) can serve as an objective measurement to characterize the three metacarpal sites of normal SDFTs, and also to discriminate a healthy SDFT from an injured one. In this paper, we propose a shock filter algorithm for the thinning of hyper-echoic structures observed in B-scan images of the SDFT. This algorithm is further enhanced by applying closing morphological operations on filtered images to facilitate extraction and quantification of fiber bundle fascicles. The mean F...
O'Rielly JL.The IgG concentration of plasma from 13 mares was measured by radial immunodiffusion when fresh and after storage at -4 degrees C and thawing by 3 methods. There was no significant (P > 0.05) reduction in the IgG concentration when plasma was thawed over 6 hours at 22 degrees C (1352.9 +/- 101.6 mg/dL) (mean +/- SEM) compared with the fresh sample (1369.5 +/- 88.1 mg/dL). In contrast, there was a significant (P < 0.05) reduction in the IgG concentration of plasma that was rapidly thawed at 57 degrees C over 50 minutes (1142.9 +/- 66.2 mg/dL), or placed in a microwave oven for 20 to 25 minutes ...
Papin J, Stuhtmann G, Martinsson G, Sieme H, Lundeheim N, Ntallaris T, Morrell JM.Removal of seminal plasma facilitates stallion sperm survival during storage, but washing may damage sperm chromatin. Therefore, sperm quality was compared in samples following single-layer centrifugation (SLC) or sperm washing and controls (extension only) in two extenders, INRA82 and INRA96. Ejaculates from six stallions were split among six treatments: SLC, sperm washing, and controls, in INRA82 and INRA96. Sperm motility and acrosome status were evaluated at 0, 24, 48, 72 and 96 hours; morphology at 0, 24, 48, 72 hours and chromatin integrity at 0 and 96 hours, with storage at 6°C. Sperm ...
Gläser KE, Davies ME, Jeffcott LB.This study was designed to examine a new role for cysteine proteinases in the process of endochondral ossification. Objective: The aim of the present study was to investigate the presence and distribution of cathepsin B and cathepsin L in equine articular cartilage during development. Methods: Full-depth cartilage samples from a total of 40 horses (age range: 4 month fetuses to 2 years) were examined and enzymes detected by immunocytochemical localisation. Results: Observations on the presence of cathepsins B and L revealed significant age-related differences, resulting in clear division of th...
Herbach N, Nagel L, Zwick T, Hermanns W.Pancreatic neuroendocrine tumors of glucagon-producing cells are extremely rare in domestic animals. In this report, we describe for the first time, to our knowledge, the incidental finding of multiple glucagon-producing neuroendocrine tumors of the pancreas of a horse. The animal was euthanized due to severe local infection after tooth extraction. On postmortem examination, multiple white nodules of up to 4 cm in diameter were observed in the pancreas. Histologically, pancreatic nodules had the appearance of neuroendocrine neoplasms with positive immunoreactivity for glucagon, synaptophysin, ...
Polack EW, King JM, Cummings JF, Mohammed HO, Birch M, Cronin T.To compare concentrations of trace minerals in the spinal cord of horses with equine motor neuron disease (EMND) with those of horses without neurologic disease (control horses). Methods: 24 horses with EMND and 22 control horses. Methods: Spinal cord trace mineral concentrations in horses with EMND and control horses were analyzed by use of inductively coupled plasma atomic emission spectroscopy (calcium, phosphorus, sodium, potassium, magnesium, copper, iron, manganese, nickel, zinc, aluminum, cobalt, and chromium), atomic absorption spectrophotometry (lead and cadmium), flameless atomic abs...
Lloyd KC, Stover SM, Pascoe JR, Pool RR.A 2.5-cm long, 0.8 mm in diameter catheter was placed percutaneously into the palmarolateral pouch of the antebrachiocarpal joint in 6 clinically normal horses. The catheter was affixed in place for 72 hours. Cytologic analysis was performed on synovial fluid specimens obtained through the catheter at postcatheterization hours (PCH) 0, 24, and 72. The horses were euthanatized at PCH 72, and macroscopic and microscopic examinations were performed on the dorsal portion of the joint capsule and the palmarolateral pouch of the catheterized and contralateral (noncatheterized) joint. Clinical, synov...
Gürler AT, Bölükbaş CS, Açici M, Umur S.Helminths of equines are one of the most important agents of parasitic diseases. Therefore, many studies have been conducted on helminths of equines in Turkey. In this article, a check list and prevalence rates of helminths of equines in Turkey have been given.
Chen J, Wang H, Li J, Liu S, Li B, Sun Y, Wang H, Manglai D.To date, the origins, domestication, and genetic structure of Chinese Mongolian horses (CMH) are poorly understood. Furthermore, there have been sparse reports on the genetic differences between CMH and Thoroughbred. In order to determine their genetic structure, understand their genetic relationships, and explore their domestication processes, we performed an extensive survey of creatine kinase (muscle isoenzyme; variations among six populations of indigenous CMH, cultivated Sanhe horses, and imported Thoroughbred. Twenty-three single-nucleotide polymorphisms were found among the 343 horse s...
Van Eenoo P, Delbeke FT, Deprez P.Clenbuterol, a beta-adrenergic agonist, is used in the treatment of recurrent airway obstruction in horses. It is prohibited by horse racing authorities, because of its stimulating and growth-promoting properties. However, information on detection times of clenbuterol after administration by nebulization is lacking. In this study, a fast, sensitive quantitative GC-MS(2) method for the detection of clenbuterol in urine was developed. Alkaline liquid-liquid extraction was followed by derivatization to a cyclic methyl boronate derivative and analysis on a Finnigan MAT GCQ instrument. Method valid...
Galuppo LD, Stover SM, Jensen DG.To compare bone fragment compression and the mechanical pushout strength and stiffness of 6.5-mm Acutrak Plus (AP) and 4.5-mm AO cortical (AO) bone screws after stabilization of a simulated equine third metacarpal (MC3) bone complete lateral condylar fracture. Methods: In vitro biomechanical paired study of screw insertion variables, bone fragment compression, and screw pushout tests using a bone screw stabilized simulated lateral condylar fracture model. Methods: Six pairs of cadaveric equine MC3s. Methods: Metacarpi were placed in a fixture and centered on a biaxial load cell in a materials ...