"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Maier-Bock H, Ehrlein HJ.During a gradually increasing exercise test heart rates were determined in healthy animals and in 2 groups of sick horse. These included 31 animals with a chronic pulmonary disorder and 5 with chronic heart disease. The alteration in heart rate was correlated with the clinical signs exhibited. In the horses with lung disease there was a close correlation between the stage of the diseases and the heart rate during the exercise test. In 3 animals with heart valve disease there was no apparent difference in heart rate compared with healthy horses. On the other hand the exercising heart rate of ho...
Riemann HP, Kaneko JJ, Haghighi S, Behymer DE, Franti CE, Ruppanner R.Hospitalized animals and stray dogs were serologically tested for antibodies against Toxoplasma gondii. In addition, the data were examined for the possibility of toxoplasmosis infection being associated with the clinical diagnosis and with the discharge status (alive vs. dead). Among 1056 hospitalized animals, 17 (20%) of 86 cats, 112 (14%) of 804 dogs, 34 (26%) of 133 horses and 6 (18%) of 33 cattle had serological evidence of infection with T. gondii. Only 22 (6%) of 342 young (median age = one year) stray dogs were seropositive. The difference in antibody prevalence between hospitalized an...
Zavy MT, Bazer FW, Sharp DC, Frank M, Thatcher WW.Prostaglandin F was measured by radioimmunoassay in uterine flushings of cycling mares on days 4, 8, 12, 14, 16, 18 and 20 post-ovulation. Prostaglandin F was significantly (P less than .05) affected by day of the estrous cycle and reached maximal levels on day 14. Least squares means for days 4, 8, 12, 14, 16, 18 and 20 were: .66, .81, 4.77, 14.31, 5.48, 3.68 and 2.97 ng/ml, respectively.
Webbon PM.The normal appearance of the superficial (SFT) and deep (DFT) digital flexor tendons was described and the difference between their histological structures was emphasised. Further differences were recognised between different sites from the same tendon and between tendons in the fore and hind limbs of the same animal. Both of the tendons underwent changes with age but although a number of alterations in the histological appearance were described, a particular change, involving a patchy loss of stainable nuclei, was found at the common site of SFT injuries. While this appearance has been seen i...
Swartzman JA, Hintz HF, Schryver HF.The effects of dietary oxalic acid on absorption, excretion, and retention of calcium was determined in Shetland ponies in 2 experiments. In each experiment, the results of feeding a control diet consisting of oats, molasses, and a complete pelleted horse ration were compared with those of feeding the control diet plus 1% oxalic acid. The diets contained 0.6% calcium in the 1st experiment and 0.45% calcium in the 2nd experiment. Oxalic acid increased the fecal excretion of calcium and decreased calcium absorption. The endogenous fecal excretion of calcium determined in the 1st experiment, usin...
Barthold SW, Olson C.Cultured cells from bovine papilloma virus (BPV)-induced fibroblastic tumors and normal dermis of cattle, horses, and hamsters were examined for cell membrane or internal neoantigens, using the indirect immunofluorescence technique. Sera from cattle and horses bearing BPV-induced fibromas cross reacted with cell membranes of tumor, but not with normal dermal cells of both species. The reaction could be blocked with homologous, but not heterologous, serum of these 2 species. Immunofluorescence was not detected with sera from hamsters bearing BPV-induced sarcomas if incubated with bovine, equine...
Mirck MH.In 3,791 horses and ponies submitted to the Department of Internal Disease of Farm Animals of the Faculty of Veterinary Medicine, Utrecht, the faeces were studied for the presence of parasites. The results were classified by age groups and months of arrival. Eggs of the Strongylus type were found to be present in 57.3 per cent of the faecal samples, eggs of Parascaris equorum were present in 6.1 per cent, eggs of Oxyuris equi in 1.2 per cent, eggs or larvae of Dictyocaulus arnfieldi in 0.2 per cent, eggs of Anoplocephala in 2.5 per cent and oocysts of Eimeria leuckarti in 0.3 per cent. Eggs of...
Tasker JB.Reference (normal) ranges were established for clinical chemistry results obtained from the Coulter Chemistry instrument on specimens from dogs, cats, horses, and cattle. These results, in general, are very similar to those reported in the current veterinary literature. The specimens obtained from horses and cows were subdivided according to age and lactation status, respectively. Significant differences were noted between the subgroups in the results of certain tests.
Baker KP, Quinn PJ.Sweet itch is an intensely pruritic dermatitis of horses recurring annually in Ireland from April to November. The tissue changes of sweet itch have similarities to immediate-type hypersensitivity reactions which occur in skin sensitised to the saliva of bloodsucking insects. There was subepidermal oedema, and marked eosinophilia; the blood vessels were tortuous and enlarged. Microfilaria were not found in serial sections of lesions of 5 affected horses. The histopathology of the immediate dermal remal reaction to the intradermal injection of Culicoides extract shows dermal vasodilation and eo...
Hanna CJ, Eyre P.Horses suffer from a respiratory condition, similar to human allergic asthma, that is characterized by severe dyspnea, wheezing, coughing, and mucus production. Mediator substances released during the allergic reaction may contract airways and pulmonary vasculature. Nothing is known of the effects of autacoids and other vasoactive substances on equine pulmonary vessels. Therefore, spiral strips of equine pulmonary vein were prepared in vitro and the effects of histamine (H), 5-hydroxytryptamine (5HT), bradykinin (BK), carbachol (Carb), and phenylephrine (phen) were studied. The order of contra...
Owen R, Maxie LL.Quadriplegia of 4 days' duration in a 3-week-old foal was caused by displacement of the dens of the axis due to a fracture at the dens growth plate. The displacement was reduced and was immobilized surgically. Two months after surgery, the foal was able to rise, walk, and trot without apparent neurologic deficiencies. Three years later, the only defect was a mild gait disturbance in the left hindlimb seen at a canter and a gallop.
Brown CM, Holmes JR.The paper reports the changing pressure values during the cardiac cycle recorded from various chambers of the heart and great vessels using 2 catheter-mounted transducers, 9 cm apart. Pulse pressures are calculated. Transvalval pressure differences are determined taking account of the effect of hydrostatic pressure between the 2 sensors. The effects of some valvular lesions and arrhythmias and of changes in intrathoracic pressure are also described.
Brown CM, Holmes JR.The paper reports observations on the duration of various phases of the cardiac cycle using a bipole ECG record as a time base from which to measure the timing of pressure changes in the chambers of the heart and great vessels. From the findings the likely sequence of mechanical events during the cardiac cycle in the atria and ventricles is described.
Garner HE, Moore JN, Johnson JH, Clark L, Amend JF, Tritschler LG, Coffmann JR, Sprouse RF, Hutcheson DP, Salem CA.Caecal fluid samples collected 8 and 24 hours after carbohydrate overload were quantitatively compared to control samples in terms of aerobic and anaerobic bacteria. Concomitant increases in lactic acid-producing bacteria and decreases in Gram negative bacteria were substantiated during the onset of acute laminitis. Progressive decreases in caecal fluid pH were also quantitated. Although endotoxin assays of caecal fluid and blood were not done, the caecal flora changes suggest its presence during the onset of acute laminitis.
Baker EF, Sasso DR, Maness K, Prichard WD, Parker RL.In 1971, more than 370 horses in south Texas were studied with respect to their clinical, virologic, and neutralizing antibody responses to vaccination with Venezuelan equine encephalomyelitis (VEE) strain TC-83. This study confirms reported findings that the vaccine used in the 1971 epizootic in the lower Rio Grande Valley of Texas was safe and efficacious. Vaccinal virus viremia titers were generally below the postulated infection threshold of epizootic vectors. In general, reactions to the vaccine were minimal and transient, with no observed abortions or deaths attributable to use of the va...
Schatzmann U, Tschudi P, Held JP, Muhlebach B.Glyceryl guaiacolate (GGE) was found to be a useful and safe casting agent when given by rapid intravenous infusion. It was administered to premedicated horses under controlled conditions at various concentrations from 10 to 20 per cent GGE solution. The onset and degree of relaxation was dependent only on the speed of infusion. For casting adult horses 350 to 450 ml of 15 per cent solution must be given within 30 to 60 seconds. A slight transient hypoxaemia occurred which seemed to be related to the animal being in lateral recumbency rather than the depressive action of GGE on respiratory fun...
De Moor A, Van Den Hende C, Moens Y, Desmet P.A long-lasting increase of the plasma bromide concentration was found in 25 horses after clinical halothane anesthesia. The plasma bromide concentration was significantly (P less than 0.005) increased at the end of anesthesia. In 18 horses, peak values were reached between 48 and 72 hours after anesthesia. Eighteen days after horses had been anesthetized, the plasma bromide concentration remained significantly (P less than 0.005) increased. Significant correlation was not found between the total dose of halothane and the plasma bromide concentration. In 1 horse reanesthetized with halothane 4 ...
Gay CC, Sullivan ND, Wilkinson JS, McLean JD, Blood DC.The case histories and clinical findings of 15 ponies with hyperlipaemia are presented. The disease was characterised by hyperlipidaemia with inappetance, progressing somnolence, muscle fasciculation, diarrhoea, and ventral oedema as the predominant clinical findings. Post mortem examinations of 12 ponies showed extensive lipidosis and vascular thrombosis with widespread secondary changes. Most cases occurred in late pregnant and early lactating mares in the summer months and it is postulated that the disease was initiated in this group by a falling nutritional plane in the face of high nutrie...
Laan TT, Butler CM, Daha TJ, van Doorn DC, van Duijkeren E, Goehring LS, Houwers DJ, van Maanen C, Picavet T, Sloet van Oldruitenborgh-Oosterbaan MM.No abstract available
Dyson S.Methods of investigating horses with suspected shoulder lameness are described and discussed. The gait of shoulder lameness is characterised and compared with that of lower forelimb lameness. If lameness is slight, differentiation may be difficult, but if moderate, upper forelimb lameness usually results in shortening of the cranial phase of the stride and a low limb flight. Clinically, it may not be possible to differentiate between shoulder and elbow lameness without intra-articular anaesthesia. Practical aspects of intra-articular anaesthesia of the shoulder joint are reviewed. Synovial flu...
Divers TJ, Radcliffe RM, Cook VL, Bookbinder LC, Hurcombe SDA.Blood products, crystalloids, and colloid fluids are used in the medical treatment of severe hemorrhage in horses with a goal of providing sufficient blood flow and oxygen delivery to vital organs. The fluid treatments for hemorrhage will vary depending upon severity and duration and whether hemorrhage is controlled or uncontrolled. Methods: With acute and severe controlled hemorrhage, treatment is focused on rapidly increasing perfusion pressure and blood flow to vital organs. This can most easily be accomplished in field cases by the administration of hypertonic saline. If isotonic crystallo...
Reilly CA, Aust SD.An intracellular, membrane-bound enzyme exhibiting both p-phenylenediamine oxidase activity and ferrous iron oxidase activity was isolated with the plasma membrane fraction of horse heart and studied for its ability to load iron into ferritin. The ferroxidase activity of the tissue oxidase was stimulated approximately twofold by horse spleen apoferritin, and the iron was loaded into ferritin. The loading of iron into ferritin by the tissue oxidase was inhibited by anti-horse serum ceruloplasmin antibody. The stoichiometry of iron oxidation and oxygen consumption during iron loading into ferrit...
Easley J.Equine dentistry has been practiced for almost 3000 years, making it one of the oldest areas of equine health care. Progress has been slow and mirrored changes seen in human medical care. Many horsemen practiced equine dentistry during the late nineteenth and early twentieth centuries. Most of what was known then concentrated on sharp enamel points and abnormal dental occlusal wear. This changed slowly in the late twentieth century as research in equine dentistry increased. Today, veterinarians performing equine dentistry focus on detailed oral examination and base treatment for proper diagno...
Steffey EP, Berry JD.Inspiratory flow rates were measured and compared in an equine intermittent positive pressure breathing-anesthesia delivery apparatus powered by a positive phase ventilator, a positive-negative phase ventilator, and a modified positive phase ventilator with automatic flow acceleration at driving pressures of 2,600, 4,400, and 5,200 mm of Hg (50, 85, and 100 psi). The last-named apparatus consistently produced the highest flows for a given ventilator setting and driving pressure. Regardless of the unit used, the greater driving pressures and high ventilator range settings produced the greatest ...
Hubbell JA, Hinchcliff KW, Grosenbaugh DA, Beard WL, Beard LA.Frusemide reduces pulmonary vascular pressures in resting horses and attenuates exercise-induced increases in these pressures in exercising horses. The mechanism underlying these effects of frusemide is unclear. We tested the hypothesis that the haemodynamic effects of frusemide are dependent on diuresis by examining the effect of frusemide in anaesthetised horses in which diuresis was prevented by ligation of ureters. Twenty four horses were assigned randomly to one of 4 treatments: 1) frusemide (1 mg/kg bwt i.v.) and intact ureters; 2) frusemide and ligated ureters; 3) saline placebo and lig...
Morley M, Loeb J.As Malcolm Morley becomes BVA president for 2022/23, Josh Loeb chats to him about his love for horses and why the veterinary profession is actually a human-centred business.
Brown MP, Gronwall R, Kroll WR, Beal C.Five foals from two to three days old were given a single oral dose of ampicillin trihydrate (20 mg/kg bodyweight [bwt]). Serum ampicillin concentrations were measured serially over a 24 h period. The study was repeated in the same foals at 16 to 21 days old. The mean peak serum ampicillin concentration at two to three days old was 5.0 micrograms/ml at 1 h after treatment; the mean peak serum concentration at 16 to 21 days old was 2.7 micrograms/ml at 2 h. The concentrations steadily declined and ampicillin was not detected in the serum from any of the foals by 24 h. Serum clearance averaged 1...
Curtis S, Ferguson DW, Luikart R, Ovnicek G.Several of the technical approaches applied to the foot overlap with regard to intent. Frog or solar support, for example, may be provided either to stabilize the distal phalanx within the hoof capsule or in an effort to unload regional pain arising from the solar surface of the foot. It is likewise obvious that some techniques such as lowering the heels to achieve phalangeal realignment and raising the heels to relieve deep digital flexor tendon tension are contradictory. In these instances, it is not that one technique is always correct but that differences exist among horses. Currently, it ...
Haltmayer E, Simhofer H.This report describes a case of a multilobular, osseous mass including parts of the right orbit, concho frontal sinus and right ventral and dorsal conchal sinuses that developed after a traumatic insult to the right maxillary sinus 4 years prior to presentation. Surgical removal of the mass including parts of the bony orbit and long-term outcome are reported. Ce rapport décrit une masse multilobulaire et osseuse comprenant des parties de l’orbite droite, des cornets nasaux frontaux et des sinus ventral et dorsal droits qui s’est développée après un traumatisme du sinus maxillaire droi...
McDowell KJ, Adams MH, Williams NM.Proteins synthesized and released in vitro by oviducts collected from horse mares during estrus and at day 4 after ovulation for bred and nonbred mares were examined by two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (2-D SDS PAGE) and fluorography. Ampullary and isthmic regions both produced a wide array of nondialyzable proteins in culture. Major proteins or groups of proteins identified according to relative molecular weight (kDa) and apparent isoelectric point (pI) were at 100 kDa, pI 8; 100-200 kDa, pI 6; 150 kDa, pI 4.5; 60-100 kDa, pI 4; and an array of polypep...
Gehlen H, Rutenberg D, Simon C, Reinhold-Fritzen B, Drozdzewska K.The aim of this review is to describe general guidelines of hygiene measures in the horse stable as well as to provide current recommendations for an outbreak of a common infectious disease. General cleanliness, hand hygiene, avoidance of stress, regular deworming, and vaccinations belong to the basic hygiene measures in a horse herd. All new or returning equids should be submitted to a quarantine period as an important prevention measure. Repeated washing and disinfection of hands may prevent spreading of infectious agents to people and horses.The conception of a hygiene plan, including gener...
Asin J, Murphy BG, Samol MA, Polanco J, Moore JD, Uzal FA.Rickets is a metabolic bone disease associated with failure of endochondral ossification and impaired osteoid mineralization in growing animals. As a consequence, affected individuals can develop gross and microscopic bone malformations. The most common causes of rickets in domestic species include vitamin D and phosphorus deficiency. Rickets has been described in multiple species; however, comprehensive postmortem characterizations with confirmatory histopathology in equids have not been published. A 6-mo-old, Thoroughbred-cross foal was diagnosed with rickets based on gross autopsy findings ...