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.
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...
Barendsz AW.The enzyme butyrylcholinesterase from horse serum catalyses the hydrolysis of certain esters. The orange-red 2,6-dichloroindophenyl acetate will be converted by the enzyme into a deep blue alcohol. The colour transformation does not occur when the enzyme is inactivated. By making use of this biochemical reaction a cheap and simple, but very sensitive and specific detection tube could bedeveloped. The tube comprises a breakable ampoule with an aqueous buffer solution, a freeze-dried preparation of the chromogenic ester with a filler promoting its dissolution, a freeze-dried preparation of butyr...
Swerczek TW.Contagious Equine Metritis (CEM) was initially reported during the 1977 breeding season in England (Crowhurst, 1977) and Ireland (Timoney, Ward & Kelly, 1977. The disease has also been diagnosed in France and Australia (Huges, Bryden & MacDonald, 1978). The first occurrence of CEM in the United States followed the importation or 2 stallions from France late in 1977 which resulted in an outbreak early in the 1978 breeding season (Swerczek, 1978). Mares usually develop clinical signs of CEM 8--10 days after being covered by an infected stallion, when a copious, greyish discharge is seen. Other m...
Voss JL, Wallace RA, Squires EL, Pickett BW, Shideler RK.Fifty-four normally cycling, non-lactating mares were given 2 injections (i.m.) of PGF-2 alpha (10 mg) 14 days apart without regard to stage of the oestrous cycle. At 19 days after the first PGF-2 alpha treatment, a single i.m. injection of either hCG (3300 i.u.) or a GnRH-analogue (500 micrograms) was administered. Each mare was inseminated with 100 X 10(6) motile spermatozoa at one of the following frequencies: once only on Day 20; every other day during oestrus or at least on Days 19 and 21; or daily during oestrus or at least on Days 19, 20, 21 and 22. Eighteen control mares received salin...
Timoney PJ, O'Reilly PJ, McArdle JF, Ward J, Harrington AM, McCormack R.Reproduction of contagious equine metritis 1977 in Pony mares was achieved with cultures of an unclassified Gram-negative coccobacillus. Infected mares developed a vaginal discharge and associated inflammatory changes of the cervix and vagina. There was evidence of variation in pathogenicity between different strains of the organism. Although all infected mares made spontaneous clinical recoveries, the Gram-negative coccobacillus persisted in the genital tracts of a considerable proportion for a variable period after challenge. Recovery of the organism was not associated solely with the occurr...
Ricketts SW, Rossdale PD.Endometrial biopsy samples before and after treatment were obtained from 10 mares naturally infected and one Pony mare experimentally infected with Contagious Equine Metritis in 1977. The histopathological features were a short-lived polymorphonuclear cell infiltration of the luminal epithelium and stroma followed by a very early and marked mononuclear cell infiltration of the stroma, including many plasma cells. The luminal epithelium responded with cellular proliferation which may have reflected a regenerative response. Following the initial acute response, intercellular basal vacuoles conta...
Samuel CA, Ricketts SW, Rossdale PD, Steven DH, Thurley KW.Endometrial biopsies obtained from mares at different stages of the oestrous cycle, during anoestrus and in various abnormal conditions were examined with the scanning electron microscope. Preliminary observations suggest that the patterns of secretory and ciliary activity in the uterine epithelium are similar to those observed by electron microscopical techniques in laboratory and other large domestic animals. The response of the epithelial cells to hormonal variations and infections is compared with that of the endometrium as seen with the light microscope.
Hawkins DL, Neely DP, Stabenfeldt GH.Six ovariectomized mares were divided into 3 groups to determine the effects of exogenous progesterone in oil and repositol progesterone on plasma progesterone concentrations. Progesterone in oil was administered in 7 daily injections in Exp. I. Progesterone concentrations were not maintained greater than 1.0 ng/ml for 24 h with 50 mg/day. However, they remained greater than 1.0 ng/ml during the last 4 days of 100 mg/day and greater than 1.5 ng/ml throughout the injection sequence of 200 mg/day. Repositol progesterone was administered on Days 1 and 7 in Exp. II. At 500 mg, progesterone concent...
Hazard GH, Hughes KL, Penson PJ.Contagious equine metritis (CEM) was first diagnosed in Australia in August 1977 and it has since been found on 6 farms in 3 states, having been isolated from about 24 mares and 2 stallions. Details are given of the epidemiology and control procedures used to combat CEM on one farm. Difficulty was experience in successfully treating one infected stallion; this was thought to be associated with inadequate cleaning and treating of the diverticulum of the urethral fossa. Introduction of the disease has had far-reaching consequences and may well result in the adoption of routine bacteriological te...
Brown PJ, Clayton HM.The pathological changes associated with the migration through the liver of P. equorum larvae were investigated. Twenty pony foals were killed at intervals of 2 to 185 days after a single infection with 160 or 8000 P. equorum eggs and 4 pony foals were killed at intervals of 94 to 144 days after twice weekly infections of 50 eggs from birth. At post-mortem examination the macroscopic changes included the development of focal haemorrhages and small, white diffuse or nodular lesions.
Microscopic lesions were found mainly around the portal triads and consisted of infiltration by cells, including...
Gay CC, Speirs VC, Christie BA, Smyth B, Parry B.Six horses, which had a foreign body obstruction of the small colon showed abdominal pain of progressing severity and intestinal tympany. On rectal examination the caecum and large colon were distended with ingesta and gas but the obstructing mass could be palpated in only 3 cases. All horses had elevated indirect blood pressure and in 3 there was also fluid distension of the stomach. Only one horse had known access to foreign material in the diet, but a further 3 were related to an exceptionally dry climate period. Five of the 6 horses recovered following surgery.
Powell DG, Whitwell K.Following an outbreak of CEM in England during 1977 a Code of Practice was introduced to control the disease in 1978. The Code recommended a bacteriological screening programme for Thoroughbred mares and stallions and improved standards of hygiene on the stud farm. As a result of the implementation of the Code a number of asymptomatic carrier mares was detected. Stallions which had transmitted CEM in 2977 and were treated did not transmit the disease during 1978. Two small outbreaks of CEM were reported during the 1978 breeding season.
Grieve RB, Moore BG, Bradley RE.A critical test was performed to evaluate the anthelmintic properties of an injectable butamisole formulation and to compare the efficiency with that of a commercially available piperazine-thiabendazole anthelmintic. The test was done in 10 horses and 15 ponies with naturally acquired parasitic infections. Butamisole was administered at the dose level of 2.5 or 3.75 mg/kg of body weight by either subcutaneous or deep intramuscular injection. Given at the dose level of 2.5 mg/kg, butamisole was highly effective (99%) against Strongylus vulgaris and moderately effective (49%) against Parascaris ...
Irvine CH.Isoelectric focussing of crude extracts of equine pituitaries was used to obtain fractions containing FSH and LH. By comparison with FSH, LH was distributed over a similar but wider pH range indicating more marked polymorphism as determined from their isoelectric point (pI). Molecules with more sialic acid showed lower pI consistent with the concept that sialic acid is the major factor in determining pI and polymorphism in FSH and LH. Appropriate fractions were labelled with 125I, purified further and used in kinetic studies. FSH and LH molecules of similar pI had similar kinetics; however, LH...
Ek N. Acta vet. scand. 1979, , 180–190. — Selected equine Pr phenotypes from a total of 55 horses of mixed breeds were investigated. The horse sera were subjected to acid starch gel electrophoresis at pH 4.8, followed by right angle electrophoresis in agarose gels containing rabbit-produced anti-Pr protein. This technique gives peaks in the agarose gels corresponding to the Pr zones in acid gels. The investigation revealed patterns of the Pr protein which were more complex than those seen when using ordinary acid starch gel electrophoresis. The phenotypes FF, II and LL showed a total of eight p...
Väihkönen LK, Ojala M, Pösö AR.In red blood cell membranes, the activity of the main lactate carrier, H+-monocarboxylate co-transporter (MCT), varies interindividually and its distribution is bimodal. To show the repeatability of MCT activity, 2 to 5 blood samples were taken, at an interval of approximately 1 year, from 51 Standardbred horses, age 2 weeks-8 years, for a total of 128 observations. The horses could be divided into low (LT) and high (HT) lactate transport activity groups. Age significantly affected (P<0.05) MCT activity such that activity was highest in foals, reached a nadir at 2-3 years, and tended to inc...
Rapoff AJ, Markel MD, Vanderby R.By use of wire ropes as the transosseous component, an external skeletal fixator for the repair of long bone fractures in horses and cattle has been designed and tested in axial compression. Theoretical methods were used in the design process to size fixator components; however, our results suggest that conventional methods of analyzing the displacement of the transosseous component may not apply to wire ropes. Large pretensions in the wire ropes are necessary to obtain functional stiffnesses for fracture fixation. Therefore, a method was sought for terminating the ropes so that an appropriate...
Sugiura T, Nakajima H.An indirect hemagglutination was developed for the diagnosis of equine infectious anemia using sheep red blood cells coated with group specific virus antigen which had been highly purified by affinity chromatography. The presence of indirect hemagglutination antibodies was demonstrated in horses with equine infectious anemia since the cells were specifically agglutinated by all the serum samples obtained from experimentally infected horses. Antibodies appeared within 35 days after inoculation, and development of which coincided well with that of precipitating and complement fixing antibodies. ...
Viscardi V, Jorge ML, Silva KM, Sad EP, Fonseca AB, Alencar NX, Lessa DA.Collection of fluid from the lower respiratory tract (LRT) plays an important role in both the pathophysiological investigation and diagnosis of respiratory tract disease. Enzymes such as ALP are, among others, indicators of cell damage or death, type II pneumocyte proliferation, and neutrophil invasion, and have been useful as biomarkers of respiratory disease in other species. Objective: The purpose of this study was to determine and compare tracheal wash (TW) ALP activity in healthy horses and horses with LRT inflammation (LRTI) determined by TW cytology profile. Methods: Tracheal washes we...
Wilkołek P, Szczepanik M, Rodzik B, Sitkowski W, Pluta M, Taszkun I, Gołyński M.Intradermal tests (IDTs) and measurement of specific immunoglobulin E class (sIgE) levels in sera are the most common and reliable methods used in allergological clinical practice. The purpose of this study was to explore the sensitization of pollen allergy in atopic horses with pollinosis and to assess the diagnostic value of the multiple allergen simultaneous tests (MASTs) compared with that of the IDT. Twenty-one Malopolski horses with typical skin hypersensitivity symptoms during pollen seasons were enrolled. Intradermal tests were performed, and allergen-specific IgE concentrations in ser...
Kirkland KD, Fales WH, Blanchard TL, Youngquist RS, Hurtgen JP.Five isolants of Pseudomonas aeruginosa collected from clinical cases of equine genital infection and one standard strain of P. aeruginosa were exposed to various concentrations of ethylene-diaminetetraacetic acid (EDTA) and tris (hydroxymethyl) aminomethane (tris buffer pH 8) and EDTA-tris lysozyme. Colony forming units of the isolants and minimal inhibitory concentrations for 11 antimicrobial agents were determined with each isolant before and after exposure to the EDTA solutions. Decreased cellular viability was found with all six isolants after exposure to the EDTA-tris solutions. Reversal...
Jenner F, Närväinen J, de Ruijter-Villani M, Stout TA, van Weeren PR, Brama P.Equine embryogenesis post implantation is not well studied, and only two-dimensional illustrations are available. A thorough appreciation of the complex three-dimensional relationship between tissues and organs and their development is, however, crucial for understanding physiological and pathological mechanisms. Objective: The goals were 2-fold: 1) to establish a freely accessible online atlas as a reference tool for the scientific and pedagogic communities; and 2) to create a framework for integration of data with known spatiotemporal distribution, such as gene expression or cell lineage. Me...
Anfossi P, Villa R, Montesissa C, Carli S.Lysine salts are often used in human pharmaceuticals to increase the solubility and absorption of acidic drugs when these are administered parenterally. In this study the intramuscular bioavailability of ketoprofen administered as the lysine salt was evaluated in horses (n = 5) treated intravenously and intramuscularly (2.2 mg/kg active substance) in a cross-over study. The absorption rate of ketoprofen administered as the lysine salt was rather low: the mean residence time increased from 31.7 min after IV injection to 128.9 min (after IM injection), and the bioavailability was high (mean 92.4...
Heffron CJ, Baker GJ.Cine-endoscopy was used to study the deglutition reflex in 2 apparently normal horses. Closure of the nasopharyngeal sphincter was brought about by a lowering of the pharyngeal roof and an elevation of the soft palate caudal to the pharyngeal ostia of the auditory tubes. The medial cartilages of the ostia were not directly involved in bringing about closure of the sphincter. It is postulated that the opening of the ostia of the auditory tubes is brought about during deglutition by the combined action of the palatopharyngeus, pterygopharyngeus and tensor veli palatini muscles.
O'Callaghan MW.We live in an age in which highly sophisticated computerized equipment and imaging methods are becoming increasingly available. Demand from clients requires that we as veterinary professionals keep our eyes on the future potential of these technologies for diagnosis and treatment. This article briefly reviews some of the techniques that are just around the corner for the progressive equine practitioner.
Friis NF, Bech J.Döhle bodies were observed in a horse suffering from a chronic pleurisy. The bodies were demonstrated in about 80 % of the neutro-phils in blood smears prepared during an acute flare-up of the disease. One to 4 bodies were found in each cell, situated in the periphery of the cytoplasm. The size of the bodies was 1–3 μ and the shape rodlike or oval. They stained blue with M-G-G. Blood smears were examined from 50 horses suffering from various diseases, but Döhle bodies could not be demonstrated in any of these cases. Döhle-Körperchen wurden bei einem Pferd mit chronischer Pleuritis beoba...
Kovár J, Dürrová E, Skurský L.The interactions of three groups of probes (berberine alkaloids, tricyclic psychopharmaca and acridine derivatives) with isoenzymes of horse liver alcohol dehydrogenase and with rat liver alcohol dehydrogenase have been examined. These compounds inhibit the activity of the EE isoenzyme of horse liver alcohol dehydrogenase but differ in their behaviour towards the steroid-active enzymes (i.e. the ES isoenzyme of horse liver alcohol dehydrognase and alcohol dehydrogenase from rat liver): psychopharmaca inhibit, acridines activate and berberines do not bind. The ligands differ also in their influ...