"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.
Perryman LE, Buening GM, McGuire TC, Torbeck RL, Poppie MJ, Sale GE.Six young horses with combined immunodeficiency were given liver cells intravenously or intraperitoneally and thymuses subcutaneously from equine fetuses ranging from 68 to 110 days of gestational age. Three of four horses given cells from fetuses over 90 days of age developed lesions compatible with graft versus host reactions. One horse given cells from an 80-day fetus developed mitogen-responsive lymphocytes, synthesized immunoglobulins of the four major equine classes, and survived to 11.5 months of age. The sixth foal receiving cells from a 68-day fetus showed no discernable effects from ...
Charman H, Long C, Coggins L.Three structural proteins of equine infectious anemia virus were purified, labeled with 125I, and utilized in radioimmunoassays with horse sera and antisera to heterologous retroviruses. Whereas radioimmunoassay titers for the major protein, p25, were 500- to 1,000-fold higher than titers in immunodiffusion, for clinical purposes these two procedures were equivalent. Antibodies to two low-molecular-weight proteins, p12 and p10, were also found in infected horses, but with a lower frequency and lower titers. As a rule, only sera positive for p25 also contained antibody to p12 and p10. Antisera ...
Fretz PB, Babiuk LA, McLaughlin B.The serological results from this study clearly show that both equine influenza and equine rhinopneumonitis viruses were present during spring and autumn epidemics of respiratory disease on Western Canadian racetracks. Approximately 11% of the horses showed significant convalescent titres to influenza while 9% showed significant convalescent titres for equine viral pneumonitis. It was noted in our study a positive vaccination history corresponded with a reduction in the severity of the respiratory infection.
Murphy JM, Severin GA, Lavach JD, Hepler DI, Lueker DC.A modified Bacillus Calmette-Guerin (BCG) preparation was used successfully in the treatment of 7 cases of equine sarcoid. The BCG preparation was injected into the lesions. The longest period of remission has been 24 months, and the shortest period of remission has been 9 months, with no signs of recurrence of the tumor in any of the presented cases.
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...
Ganjam VK.Changes in the daily secretory patterns of testosterone and other 17 beta-hydroxyandrogen, total oestrogens and total corticoids were investigated in 7 stallions. Pulsatile fluctuations in plasma hormone levels were found in the serial blood samples collected hourly for 24 h in all animals. The plasma profiles indicated that corticoids, oestrogens and androgens were secreted episodically at all times in stallions. A significant correlation was observed between the precursor and products of delta 4-ene and delta 5-ene pathways and in inverse correlation (r = -0.68; P less than 0.01) was observe...
Stabenfeldt GH, Hughes JP, Kennedy PC, Meagher DM, Neely DP.The clinical, structural and functional characteristics of ovarian tumours were studied in 10 mares. Proliferation of the granulosa cells of large and small follicles and the presence of various numbers of Leydig-like cells in the theca interna were the predominant microscopic findings in 9 of the mares. All 9 of these animals had higher than normal (P less than 0.005) concentrations of testosterone in the peripheral plasma; 2 animals which exhibited male behaviour had testosterone concentrations greater than 100 pg/ml and the largest number of Leydig-like cells in the theca. Mares with lower ...
Mascarello F, Veggetti A.The intrinsic laryngeal muscles of the horse, donkey, sheep, ox, pig, dog and cat were examined for myosin ATPase, following acid and alkali pre-incubation, SDH and M-alphaGPDH activities. In all laryngeal muscles two fibre types, betaR and alphaR, belonging to slow and fast-contracting, fatigue-resistant motor units (types S and FR) were present in different proportions. The alphaW fibre type, belonging to fast-contracting and fatigue-resistant motor units was absent (type FF). The alphaR fibres of the dog and the cat were subdivided into groups by the various degrees of acid stable myosin AT...
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.
Smyth GB.An abnormal cryptorchid testicle removed from the abdominal cavity of a 4 year old Thoroughbred stallion is described. The abnormal organ conforms to the requirements of Willis (1960) for a teratoma. The difference between these tumours in man and horses is discussed.
Brotherton HO, Yost RA.A screening and confirmation procedure for drugs and metabolites in the blood serum and urine of racing animals was developed. Equine blood serum was spiked with low concentrations of several drugs of interest. Canine blood serum and urine were collected following oral doses of diethylcarbamazine, procaine, and phenylbutazone. Serum, urine, and extracts of each were analyzed, using a triple quadrupole mass spectrometer. Simultaneous screening of up to 50 drugs was possible in a single sample, in less than 2 minutes. Detection limits for most compounds were in the ng/ml to microgram/ml range, u...
Bukowiecki CF, van Ee RT, Schneiter HL.A comminuted scapular fracture in a foal was treated surgically by use of 2 dynamic compression plates. The plates were applied upside down, so that the convex surface of the plate faced the bone. At 5 months after surgery, the plates were removed, and the foal recovered without complications.
Lotstra RJ, van den Broek J, Power T, Marr CM, Wijnberg ID.Atrial fibrillation is a common equine arrhythmia. Quinidine alone, or with digoxin are common treatments. Studies on outcome in Warmblood populations in which duration of the AF is often unknown are limited. Objective: To identify the factors that are associated with the success of full treatment cardioversion with oral medication, and establish whether there are differences in these factors between institutions. Methods: Retrospective case series using patient records of Equine University Clinic of Utrecht University and Rossdales Equine Hospital, Newmarket. Methods: Forty-nine horses treate...
Schumacher J, Crossland LE.Primary paranasal sinusitis, complicated by inspissated purulent exudate in a ventral conchal sinus, was diagnosed in 3 horses. Partial nasal obstruction, caused by axial deviation of the ventral concha, was detected endoscopically in 2 of the horses. A mass, dorsal to the maxillary molars, was detected via a lateral radiographic view of the skull of 3 horses and on the dorsoventral view of 1 of the horses. Inspissated purulent exudate was removed from the ventral conchal sinus of the horses via trephination of the conchofrontal sinus and penetration of the caudal wall of the ventral conchal s...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kokado H, Kondo T.In order to establish an efficient system for serological diagnosis of equine viral arteritis in Japan, we compared enzyme-linked immunosorbent assays (ELISAs) provided by two manufacturers (Nisseiken Co., Ltd., Tokyo, Japan, and VMRD Inc., Pullman, WA, U.S.A.) by testing a series of horse sera. The results revealed that 159 of 160 virus-neutralizing (VN) antibody-positive serum samples were positive in both the Nisseiken-ELISA and VMRD-ELISA. Of the VN-negative sera (n=157), 134 and 154 samples were negative in the Nisseiken-ELISA and VMRD-ELISA, respectively. Sensitivity was 99.4% for both t...
Tobin T, Blake JW, Tai CY, Arnett S.Rapid intravenous injection of 1 g of procaine hydrochloride in Thoroughbred mares produced variable signs of central nervous system excitation for as long as 4 minutes. Plasma concentrations of procaine were similarly variable and transient, decreasing with a half-life of approximately 25 minutes. In vitro, plasma from freshly collected equine blood hydrolyzed procaine with a half-life of approximately 7.5 minutes. This hydrolysis was apparently due to plasma esterases. Penicillin, when added free or complexed as procaine-penicillin, did not protect procaine against hydrolysis by these plasma...
Henneman K.Addressing poor performance issues in horses is a common yet challenging request to veterinarians. Often, there are limited field diagnostic or therapy choices. Growing lay popularity in integrative therapies, as well as increasing clinical incorporation, is creating more awareness of their clinical applications. Many modalities are showing increasing evidence of positive outcomes with minimal harm, but additional safety and efficacy evaluation is needed. Integrative modalities have unique ways of perceiving disease patterns that are different from more modern approaches, and these different p...
Frape DL.There is no clear evidence that the chronic requirement for any non-energy yielding nutrient rises in proportion as the energy requirement increases with hard work. The need for protein, and probably that for calcium, remain a function of bodyweight daily. Some proportionality with energy may exist for certain nutrients, although the evidence has not been adduced. For example, because of an increase in both the proportion and amount of propionic acid in the volatile fatty acids of caecal contents, the tissue requirement for vitamin B12 may rise with an increase in the rate of energy metabolism...
Kraus BM, Richardson DW, Nunamaker DM, Ross MW.To report the outcome of surgical treatment of comminuted fractures of the proximal phalanx in horses. Methods: Retrospective study. Methods: 64 horses. Methods: Medical records and radiographs were reviewed to obtain information regarding signalment, fracture classification, and treatment. Follow-up information was obtained by telephone conversation or evaluation of production records. Results: Thirty-eight horses had moderately comminuted fractures of the proximal phalanx. Two horses were euthanatized immediately. Fractures of the proximal phalanx in 36 horses were repaired with open reducti...
McCarthy PH.A description is given of 75 features present in the normal tarsus of the standing horse which are apparent due to visible skin contours overlying them. Depending on whether or not the pelvic limb is supporting full weight or resting, some contours alter their configuration. Therefore the contour of each underlying feature is described separately for each stance of the limb. It is considered that visual inspection and identification of the apparent superficial features of the normal equine tarsus form the basis of orientation and clinical inspection. Furthermore, these features provide referen...