Equine Science encompasses the study of horses and their management, health, and performance. This field integrates various scientific disciplines such as biology, genetics, nutrition, physiology, and veterinary medicine to understand and improve the well-being and capabilities of horses. Areas of focus include equine anatomy, reproduction, behavior, and disease prevention. Research in equine science aims to enhance horse care, optimize training and performance, and address health challenges. This page compiles peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine science, providing insights into the latest advancements and methodologies in the field.
Allen BV.A technique for automating equine differential leucocyte counts by analysis of volume distribution curves using the Coulter Channelyzer has been developed and evaluated. A comparison between the results obtained by this method and standard microscopic techniques showed good agreement in most cases. Blood samples can be analysed for both differential and total leucocyte counts at a rate of 25/h. For each sample an average 16,000 leucocytes are classified by the Channelyzer. The method of volume analysis is suitable for the precise counting of polymorphonuclear neutrophils, lymphocytes and eosin...
Gunn HM.A modification of the histochemical reaction to demonstrate myosin adenosine triphosphatase activity in skeletal (striated) muscle was used to define the density of capillaries in transverse sections of 3 muscles (semitendinosus, diaphragm, and pectoralis transversus) of horses and dogs. Thoroughbred horses and Greyhound dogs, breeds noted for their speed in running, were compared with other members of their respective species. Thoroughbred cross horses were grouped with non-Thoroughbreds for comparison with Thoroughbreds. The area of muscle supplied by a capillary was remarkably similar in mu...
Dixon KE, Kreider JL.Fifty ejaculates, ten from each of 5 mature stallions, were utilized to study the effects of calcium and fatty acids on equine spermatozoa which were isolated in 3% Bovine Serum Albumin (BSA). The ejaculates were evaluated for percent motile spermatozoa, rate of forward movement, debris, primary abnormalities and secondary abnormalities. The isolation procedure consisted of layering 2 ml of diluted semen (100 x 10(6) spermatozoa/ml) over 6 ml of 3% BSA in 13 x 125 mm columns in a water bath (37 degrees C). After 30 min., the top semen layer and upper half of the BSA layer were withdrawn from a...
Rowlands IW.The world-wide foaling rate in the mare is low and in the Hannoverian breed has remained asymptotic at about 50 per cent for over 150 years. In an attempt to discover some of the possible reasons for this low fertility rate, the evolutionary history of the perissodactyls, the odd-toed ungulates, is reviewed here. Of the 156 genera of this order, 152 are in the fossil record; this gives them the highest extermination rate of all the mammal groups. Some of the unusual and unique features of the reproductive physiology of the mare and their possible association with low fertility are considered.
Dees WL, Sorensen AM, Kemp WM, McArthur NH.Immunohistochemical localization of the decapeptide gonadotropin releasing hormone (GnRH) in neural structures in the pony brain and infundibulum (INF) was conducted at the light-microscopic level. This procedure utilized an antiserum generated against GnRH conjugated to bovine serum albumin. In the rostral INF, GnRH was distributed mainly in the external layer, with greatest concentrations adjacent to the long capillary loops of the hypophyseal portal system. The intermediate portion of the INF contained the hormone throughout the external layer, especially in the dorsolateral regions just ve...
Pascoe RR.The effect on the fertility of mares during two outbreaks of equine coital exanthema have been described. Conception was not prevented, nor was pregnancy terminated in mares showing active lesions of coital exanthema. Normal pregnancy rates occurred in mares served during active infection of the stallions. Origin of the disease was not determined.
Munk Z, Dusek J.The fertility problems were studied in the herd of the English Thoroughbred horse on the Napajedla stud farm. Breeding records for the period from 1880 to 1972 were used as the starting data. The survey comprised 32 stallions. The relationship between fertility and the number of matings was calculated by the chi 2 quantity. The calculated values are highly variable. However, it is generally seen in most of the stallions that the number of matings per heat (i. e. one or several matings) had no significant influence on the pregnancy of mares and on the fertility values of the stallions. A higher...
Blue MG.This study provides accumulated data to assist the definition of karyotypes from normal and infertile horses. The normal karyotype of the horse (2n = 64) was characterized following Giemsa staining and C- banding, and 23% aneuploidy was found among chromosome counts of cells prepared from 44 clinically normal horses and 24 equine embryos. These expected variations in chromosome counts are especially important in the evaluation of potential mosaicism. Centromere staining was shown to be a valuable aid for the identification of specific chromosomes, in particular the sex chromosomes. Sex chromat...
Araujo-Viel MS, Juliano L, Prado ES.The synthetic tridecapeptide Gly-Leu-Met-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg was used as a model substrate for horse urinary and porcine pancreatic kallikreins. The Met-Lys bond is hydrolyzed selectively by both enzymes. Oxidation of the methionine residue to sulfoxide made the peptide resistant to both kallikreins. Substitution of either the methionine or lysine residues by norleucine led to peptides in which the Nle-Lys or the Met-Nle bonds, respectively, were susceptible to the urinary kallikrein. The esterolytic and Met-Lys bond-splitting activities of both enzymes were inhibited simil...
Goyal HO, MacCallum FJ, Brown MP, Delack JB.Measurements were made of growth at the extremities of all the long bones of the left limbs of 23 horses between 52 and 104 days of age. Growth rates were more rapid in the younger than in the older animals. Growth was more rapid in the hind limb than in the forelimb. Growth rates were greater for males than in females. Although this age group represents only two of the 60 or so months necessary for maturity to be reached, oxytetracycline bone-labelling produced results which are more precise than measurements obtained by other methods. This study provides a substantial amount of data for an a...
Koerber SC, Dunn MF.These rapid-scanning stopped-flow kinetic studies of the equine liver alcohol dehydrogenase-catalyzed reduction of p-nitrobenzaldehyde by NADH and (4R)-4-deuterio NADH (NADD) under single turnover conditions establish : (1) The reaction is biphasic using NADD as coenzyme, k1 approximately 200 sec-1, k2 = 0.5 sec-1 and the amplitude ratio (A1)/(A1 + A2) approximately equal to 0.5. (2) Each phase of the reaction involves the oxidation of enzyme-bound reduced coenzyme. (3) The recycling of sites in the presence of 20 mM pyrazole is negligible. (4) The rates of E(NAD-pyrazole) complex formation at...
Liefman CE.Successful active immunisation of horses against tetanus is dependent on a number of factors of which the toxoid preparation used, its method of application and the ability of the individual horse to respond are fundamental. Two immunisation schedules using an aluminium-based toxoid preparation were examined and the protection determined by monitoring the level of antitoxin afforded by each schedule. The results obtained demonstrated that 2 doses of this toxoid are necessary to ensure 12 months protection in all horses. These results are discussed in relation to the factors involved in active ...
Burton SC, Hintz HF, Kemen MJ, Holmes DF.In a study with 15 neonatal foals (5 per treatment group), foals were fed within 4 hours of birth as follows: 250 ml of colostrum, 250 ml of lyophilized serum reconstituted at 5 times the original concentration, or 250 ml of a mixture (1:1) of colostrum and lyophilized serum. Foal serum samples were tested for immunoglobulin (Ig)G concentration and titrated for anti-equine rhinovirus 1 and anti-equine influenza A1 and A2 antibodies at 0 and 24 hours after foals were born. Except in a foal which had suckled the dam before treatment, there was no evidence of IgG or specific viral antibodies in t...
Manohar M, Thurmon JC, Tranquilli WJ, Shawley RV, Froelich P.A technique was developed for long-term catheterization of the coronary sinus in calves and ponies. A catheter with a 10 to 12 cm-long stiff segment was implanted via right lateral thoracotomy. Catheters were kept patent up to 10 weeks after the surgical procedure. At that time, location of the catheter tip was confirmed both by determining oxygen tension of the anaerobically sampled blood and by radiography. Base-line values of oxygen venous blood of non-anesthetized calves and ponies are reported.
Webb PD, Steven DH.The adrenal cortex from twelve fetal foals (gestational ages from 61 to 300 days) was examined by light and electron microscopy. Adrenal glands from three newborn foals were also examined by light microscopy. Between 61 and 100 days of gestation the adrenal cortex became organised into two distinct regions, the zona glomerulosa and zona fasciculata, which grew steadily in thickness until the 300th day. Between 300 days and birth there was a dramatic increase in the width of the zona fasciculata. From 200 days a narrow band of compact cells marked the cortico-medullary border. Though these cell...
Karasek M, Cozzi B.Previous studies on the ultrastructure of the horse pineal gland did not report the presence of "synaptic" ribbons, functionally enigmatic pinealocyte organelles regularly occurring in other mammalian species. The aim of the present study was to reinvestigate the horse pinealocyte in this respect. Careful investigations here reported allowed detection of "synaptic" ribbons in the pinealocytes of all the examined animals, although in a relatively low number (5.4 +/- 2.0 per 20,000 microns 2 of pineal tissue; mean +/- SD). The ultrastructure of "synaptic" ribbons in pinealocytes of the horse res...
Klugh DO.A 5-month-old quarter horse filly was presented for evaluation of a congenital overbite. The horse was diagnosed with a class 2 malocclusion. A non-removable, acrylic bite plane was constructed to provide a surface for the occlusal forces to be directed in a manner maintaining the normal anatomic position of the premaxilla. The preservation of normal anatomic relationships provided free range of motion of the mandible and maximized its growth potential, limiting the malocclusion. Although normal occlusion was not attained, partial incisor occlusion was present 20-months following initial treat...
Bossut DF, Leshin LS, Malven PV.Radioimmunoassay procedures were developed and validated for the quantification of beta-endorphin (beta-EP)-like immunoreactivity in equine plasma. beta-EP could be quantitatively extracted from plasma with silicic acid powder and subsequently assayed, however, valid estimates of this hormone could also be obtained on unextracted plasma. Although beta-lipotropin (beta-LPH) cross-reacted in the assay, it was not necessary to correct for beta-LPH activity when assaying unextracted plasma because chromatographic analyses showed that 92% of the immunoreactivity in plasma extracts was similar in mo...
Caston SS, Reinertson EL.Musculoskeletal disorders comprise a large portion of the conditions treated by equine veterinarians. Surgical intervention is the treatment of choice in many cases. The body of literature describing and exploring surgical correction of musculoskeletal disorders in horses is steadily growing but still lacking. At this juncture, we can use what information we have with the understanding that as the quality of research advances, we should apply stricter standards to the evidence we use to answer our clinical questions.
Rutgers HC, Stibbe S, van den Ingh TS, Breukink HJ.The case of a 16-year-old mare with multiple dermal lymphosarcoma of the histiolymphocytic type is described. Leukaemic changes were not found to be present in the superficial and internal lymph nodes or in the visceral organs.
McKinney AR, Ridley DD, Suann CJ.After oral administration to a thoroughbred gelding, the anabolic steroid norethandrolone was converted into a complex mixture of oxygenated metabolites. These metabolites were extracted from the urine, deconjugated by methanolysis and converted to their O-methyloxime trimethylsilyl derivatives. Gas chromatographic/mass spectrometric analysis indicated the major metabolites to be 19-norpregnane-3,16,17-triols, 19-norpregnane-3,17,20-triols and 3,17-dihydroxy-19-norpregnan-21-oic acids. Some minor metabolites were also detected.
Kirkpatrick CJ, Ernst NS, Trumble TN.There are limited radiographic-guided injection techniques of the insertion of the distal interphalangeal joint (DIPJ) collateral ligaments. The objective of this study was to develop and evaluate a palmar/plantar radiographic-guided injection of the collateral ligament insertion in cadavers. Fifty limbs were used to develop the technique and 24 additional limbs were used to evaluate accuracy. An 18 G, 9 cm spinal needle was placed in the depression between the palmar digital neurovascular bundle and arch of the ungular cartilage with dorsodistal advancement towards the distal phalanx collat...
Grahwit G.A historical review is given on the reasons to use restraint measures in animals, their definitions and classifications as well as their mode of action. An attempt is made to give an assessment of these measures according to animal welfare aspects formerly and today. Special emphasis is put on considerations in conformity with the "reasonable reason", as required in the German Animal Welfare Act.
Willsallen H, Heller J, Kark L, Hilbert BJ.In vitro comparison of the mechanical properties of braided polyurethane elastomer (Lycra®) and braided polyester (Ethibond™) (1) when inserted into the muscular process of the arytenoid cartilage and (2) as suture loops. Methods: Experimental. Methods: Equine cadaver larynges (n = 15). Methods: The muscular processes (n = 30) of the arytenoid cartilages were dissected from each larynx and embedded in a resin base. Lycra® and Ethibond™ prostheses were randomly allocated to the left or right muscular process and each underwent cyclic fatigue (25-50 N) followed by load-to-failure...