"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.
Smith BP, Robinson RC.Five out of 6 foals between 2 and 4 months old, on a ranch in northern California, developed pneumonia within a 3 week period in June and July 1978. Corynebacterium equi was recovered from each of the 5 foals by transtracheal aspiration. Clinical signs were variable but included increased respiratory rate, fever, cough, nasal discharge, harsh airway sounds over middle sized airways and wheezing over small airways. Cyanosis was present in the most severely affected foal. Radiographic findings included diffusely increased interstitial and peribronchial densities, areas of consolidation and, in 3...
Marsh MV, Caldwell J, Smith RL, Horner MW, Houghton E, Moss MS.1. 14C-Labelled benzoic acid, salicylic acid and 2-naphthylacetic acid were administered orally to horses, and urinary metabolites investigated by chromatographic and mass spectral techniques. 2. [14C]Benzoic acid (5 mg/kg) was eliminated rapidly in the urine, and quantitatively recovered in 24 h. The major urinary metabolite was hippuric acid (95% of dose) with much smaller amounts of benzoic acid, benzoyl glucuronide and 3-hydroxy-3-phenylpropionic acid. Administration of [ring-D5]benzoic acid together with [14C]benzoic acid to a pony permitted the mass spectral determination of metabolites ...
Thomson JR, McPherson EA.When stabled in a controlled environment, horses effected with chronic obstructive pulmonary disease (COPD) became clinically asymptomatic in 4 to 32 days (mean [+/-sd] 9.1 +/- 4.9 days), the time being influenced most by the severity of the disease judged on maximum intrathoracic pressure change (Max delta Ppl) and the age of the animal. Sodium cromoglycate, a drug widely used for prophylaxis of allergic respiratory disease in man, was administered by inhalation to 56 COPD-affected horses. The results showed that a linear response existed between the number of successive days treatment with t...
Brown MP, Stover SM, Kelly RH, Farver TB.Six healthy adult mares were given a single dose of kanamycin sulfate (200 mg/ml) IM at a dosage rate of 5 mg/kg of body weight. Kanamycin concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The mean peak serum kanamycin concentration was 12.55 microgram/ml at 1 hour. Mean peak kanamycin concentrations in synovial fluid and peritoneal fluid were 7.25 microgram/ml and 9.27 microgram/ml at 2 hours and 3 hours, respectively. These concentrations decreased steadily in parallel with serum concentrations and were still measurable at 48 h...
Rooney JR.An hypothesis on the pathogenesis of curb in horses is considered in the light of conformation, work and the appropriate mechanics. Prevention consists of graded work until the planter tarsal ligament has strengthened sufficiently to withstand maximum normal forces.
Coryn M, De Morr A, Bouters R, Vandeplassche M.The authors analysed clinical, histological and hormonal data obtained from 205 cryptorchid horses. The majority of the unilaterally and bilaterally retained testes were located in the inguinal canal; however, the ratio of inguinal vs abdominal retention appeared to decrease with advancing age. In unilateral cryptorchidism, a pronounced preference was noted for left abdominal retention, whereas for inguinal cryptorchids, the retained testes occurred equally on both sides. Right inguinal retention was found to decrease with advancing age. Histology of cryptorchid testes revealed apparently norm...
Snow DH, Douglas TA, Thompson H, Parkins JJ, Holmes PH.Toxic effects of phenylbutazone (PBZ) in ponies and horses were studied, using a variety of biochemical, pathophysiologic, and pathologic methods. At dosage levels of 10 to 12 mg/kg of body weight/day for 8 to 10 days, ponies frequently developed clinical signs of toxicosis characterized by hypoproteinemia. Studies using 51CrCl3 demonstrated that PBZ caused a protein-losing gastroenteropathy. The plasma loss was usually associated with gastrointestinal ulceration, but sometimes occurred without obvious lesions in mildly affected animals. Similar studies (8.2 mg/kg/day for 13 days) in Thoroughb...
Baker CB, Newton DI, Mather EC, Oxender WD.The length of diestrus was not changed in 4 mares by taking endometrial biopsy specimens during estrus. In contrast, taking endometrial biopsy specimens on postovulation day 4 induced premature luteolysis and significantly (P less than 0.05) reduced the length of diestrus. A concurrent decrease in serum progesterone occurred to verify the premature luteolysis in these mares. Bacterial cultures of endometrial swab samples from these mares were negative for growth at the first estrus before and after the last biopsy procedures, indicating that luteolysis was induced by the biopsy procedure and w...
Stover SM, Brown MP, Kelly RH, Farver TB.Six healthy adult mares were given a single dose (25 mg/kg of body weight) of sodium oxacillin IM. Oxacillin concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The mean peak serum oxacillin concentration was 9.75 microgram/ml at 0.5 hour after injection. Mean peak oxacillin concentrations in synovial and peritoneal fluids were 1.45 microgram/ml and 2.60 microgram/ml at 1 hour and 2 hours, respectively. These concentrations decreased in parallel with serum values and were not measurable at 48 hours. Urine concentrations of oxacilli...
Wells PW, McBeath DG, Eyre P, Hanna CJ.This article attempts to relate some of the more recently accepted concepts of immunology to an understanding of the mechanisms of immunity in the horse. The cellular mechanisms involved in the immune response are outlined, with an indication of their likely role in humoral and cell-mediated immunity. In describing the humoral immune response, the structure and function of the different equine immunoglobulins are reviewed. The significance of humoral and cell-mediated immune responses are considered in relation to actively and passively acquired immunity.
Salama SA, Dardiri AH, Awad FI, Soliman AM, Amin MM.African horsesickness virus was isolated from blood samples of street dogs in Aswan Province in Arab Republic of Egypt. Of six isolated "dog strain" African horsesickness viruses, three viruses designated D2, D6 and D10 have been identified as type 9 African horsesickness virus. Methods of isolation, tissue culture adaptation, serological indentification and typing are described. Horses experimentally infected with dog viruses showed febrile reaction and characteristic clinical and pathological signs of African horsesickness. Reisolation of African horsesickness virus type 9 was achieved from ...
Moens Y, De Moor A.The carbon dioxide content of respiratory gases may be monitored by the use of an infra-red carbon dioxide analyser. The technique allows continuous and non-invasive recording of important information concerning the ventilatory, circulatory and metabolic states of the anaesthetised horse. Some of the monitoring capabilities of a carbon dioxide analyser (capnograph) are reviewed with illustrations from cases anaesthetised in the authors' clinic. Technical faults in the anaesthetic apparatus and the connections with the "patient" could be readily detected and emergency situations immediately rec...
Moore JN, Garner HE, Coffman JR.Experimental carbohydrate overload of 15 horses resulted in consistent haematological changes during development of laminitis hypertension. Significant alterations in packed cell volume, leucocyte differential count, serum glucose levels and protein values occurred before onset of Obel grade 3 lameness and hyperkinetic circulatory state. Blood platelets were significantly decreased 8 h after the onset of severe lameness. Findings in this study were indicative of haemoconcentration due to compartmental fluid shifts and leucocytic stress response consistent with increased circulating adrenogluco...
Henry RW, Diesem CD.Radial and median motor nerve conduction velocities were determined on 10 clinically healthy 1- to 11-year-old ponies. These velocities were obtained by stimulation at the brachial plexus directly through a surgical incision and later in the ambulatory pony via implanted Formvar-coated wire electrodes. Percutaneous stimulation was used at the cubital region in both anesthetized and ambulatory ponies. The values for radial motor nerve fibers ranged from 96.4 to 100 m/s. These were 15.3% faster than previously reported distal values. Median motor nerve fiber values ranged from 86.8 to 90.2 m/s, ...
Stadler P, Weinberger T, Kinkel N, Deegen E.B- and M-mode echocardiography was performed on 38 horses. 34 patients had systolic heart murmur with the point of maximal intensity over mitral valve. Additionally, 17 of these patients were examined with the pulsed wave doppler echocardiography (Vingmed 200). In 26 patients with cardiac murmur and in 4 patients without cardiac murmur a mitral valve insufficiency was diagnosed by echocardiography. In 8 horses with a systolic murmur over mitral valve M- and B-mode evaluation could not reveal a haemodynamic importance of the murmur. The diagnosis of MVI was based on a dilation of left atrium wi...
Kelley DE, Schnobrich MR, Gayer S, Scoggin C, Bradcamp E, Canisso IF.The objective of this study was to compare a commercially available leukocyte esterase strip test with endometrial cytology in diagnosing endometritis and establish a cutoff point, sensitivity, and specificity for the leukocyte esterase test (LET). Forty-six light breed mares presented for breeding management were enrolled in this study. Transrectal palpation and ultrasonography examinations were performed to determine when the mares were in estrus. Kalayjian endometrial swabs were used for culture, cytology, and the LET by using the cap to retrieve an endometrial scraping. Thirty-six mares ha...
Feldkamp M.The article reviews in a critical survey the current opinions on the possibilities of improving the motor functions of cerebral palsied children with the help of riding therapy. Furthermore, the essential motor difficulties with spasm, athetosis and ataxia are described. It is demonstrated that only a small number of these typical difficulties can be tackled by means of riding therapy and that some key problems, particularly encountered by the spastics, cannot be solved. If, despite these facts, the favourable effects of riding on the cerebral palsied cannot be denied, then this must be attrib...
Attenburrow DP, Bowring CS, Vennart W.The detection of radionuclide activity in the living equine skeleton, using bone seeking radiopharmaceuticals and a hand-held radiation detector, is reported. Pathological changes in bone can be detected and subsequent development monitored. The availability and use of this diagnostic technique in equine practice is discussed.
Diehl M, Gerber H, Schifferli D, Nicolet J.A systemic investigation of wound infection in the horse after operative treatment of large wounds reveals that the age of the wound is of critical importance. The limit for an uncomplicated healing process lies around four hours. The duration of the operation itself is of little significance, the location of the lesion on the body of the horse, however, plays a major role. The pattern of isolated bacterial organisms is discussed in relation to the duration of hospital treatment. It is concluded that a systemic antibiotic therapy is of no value and that a local antibiotic therapy is only indic...
Watt BC, Beck BE.Diagnosis and removal of a nasal polyp in a horse using standing chemical restraint and readily available equipment are described. Histopathology of the polyp and differential diagnoses are discussed.
Blue MG.Minor accidents during natural mating are common occurrences during the breeding of horses. Mares may suffer from a variety of genital injuries including vulval separations, vaginal lacerations and, less commonly, vaginal rupture. Possible sequelae to, and management of, these injuries are described, with additional mention of false entry by the stallion and persistent hymen in maiden mares. Vaginal rupture during natural mating can lead to death of the mare. The implications for litigation involving veterinary surgeons and horse breeders are discussed.
Podadera JM, Bell RJ, Dart AJ.Two horses presented with a history of severe lameness that was localised to the area around the second phalanx (P2) of one forelimb. Radiographs of the second phalanx of both horses were unremarkable, apart from some smooth periosteal new bone production on the dorsum of P2. Magnetic resonance imaging revealed a non-displaced fracture of P2 in both horses. One horse was euthanased because of a poor prognosis for racing, but the second horse was treated conservatively and salvaged for breeding. Magnetic resonance imaging is a newer imaging modality in horses and may be useful in diagnosing cas...
Ineson AC, Rogers CW, Firth EC, Gee EK.To compare subjective and quantitative methods of assessing physeal swelling of the distal third metacarpal (Mc3) and metatarsal (Mt3) bones of Thoroughbred foals. Methods: The fetlocks of 16 Thoroughbred foals were filmed on five occasions over a period of 5 months and the video images were transferred to computer and digitised. The rate of change of each of the medial and lateral contours of the distal Mc3 and Mt3 bones was determined by calculating values for the second derivative of the contour. The degree of physeal swelling at the same site was subjectively assessed and allocated a grade...
Quintanar MN, Millar TP, Burd MA.The limb of the equine athlete is subjected to all types of various stressors during exercise. To ensure the health of the horse and to prevent the possibility of lameness, it has been a common practice to apply cold therapy to the distal limb of the horse pre- and post-exercise. Commercially available boots are widely available for the application of cold therapy. To test the effectiveness of the boot, 6 healthy performance level sport type horses were exercised at a walk, trot, and canter in a round-pen and then subjected to the application of the ice boot for 20 minutes on a treatment leg, ...
Reed SM.The veterinarian needs to be able to incorporate an accurate neurologic examination as a portion of the pre-purchase evaluation. Subtle neurologic deficits may be hidden by musculoskeletal disease or missed as a result of lack of knowledge or understanding of these disorders. It is important to known which musculoskeletal disorders are commonly associated with neurologic disease to better assist the buyer with the decision about whether to purchase the animal.
Gerlach K, Mader D, Delling U, Theuß T, Müller K, Offhaus J, Berner D.The aim of the present study was to verify the diagnostic validity of low-field magnetic-resonance-imaging (MRI) findings in septic diseases of the foot region following penetrating sole injuries caused by nails. Methods: MRI examinations were performed in 10 horses with injuries in the foot region. The diagnostic findings were validated by conventional methods (clinical, surgical, radiological, sonographic, and computed tomographic findings and/or post-mortem histological examination). Results: Navicular bone involvement was revealed most accurately, with a high degree of predictability, and ...
Allen D, White NA, Foerner JF, Gordon BJ.Thirteen horses with chronic refractory laminitis were evaluated and treated. In each horse, deep digital flexor tenotomy was performed on all affected limbs at the level of the midpastern. Five horses returned to limited athletic endeavors, 6 horses improved and were comfortable on pasture, 1 horse improved clinically, but was euthanatized for economic reasons, and 1 horse improved, but deteriorated 9 months after surgery and was euthanatized. Results of this study indicated that deep digital flexor tenotomy at the level of the midpastern can be used effectively as a salvage procedure in hors...
Kalsbeek HC.Non-surgical correction of nephrosplenic entrapment of the left colon was attempted in 27 cases. In two cases the method failed and a laparotomy was necessary. Two other horses had a recurrence, one of which underwent laparotomy because of torsion of the caecal body.
Beech J.An 18-month-old male Quarter Horse was referred for evaluation of a tic that had started after injury to the right forelimb 4 weeks earlier. The right forelimb appeared paretic and had constant regular twitches of variable intensity that were usually sufficiently forceful to move the trunk, neck, and head. The horse frequently threw the limb forward. The twitch persisted during sleep but disappeared during general anesthesia and following sedation with xylazine. It was unaffected by acetylpromazine, diphenylhydantoin, diazepam, carbamazepine, trimethadione, procainamide, quinidine, propranolol...