"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.
Stewart JH, Rose RJ, Barko AM.The effect of oxygen administration on blood gas values was examined in six newborn foals from birth to seven days old. Three variables were studied: the effect of increasing age on the ability to elevate arterial oxygen tension (Pao2), the effect of duration of oxygen delivery on Pao2 and the effect of method of administration. The results demonstrated a significant effect of age on the ability to increase Pao2 values, with the highest Pao2 values being found at seven days old. The duration of oxygen administration caused little change in Pao2 values; peak values were reached after 2 mins of ...
Prescott JF, Gannon VP, Kittler G, Hlywka G.Results are presented of antimicrobial disc diffusion susceptibility testing on commonly isolated bacterial pathogens made at the Ontario Veterinary College Diagnostic Bacteriology Laboratory in 1981 and 1982. Nearly 2 000 isolates from horses, cattle, dogs and cats were tested. Comparison of resistance in the same bacterial species isolated from different animal species showed significant differences between some of the same antibiotics.
Allen WR, Pashen RL.The blastomeres of 192- to 8-cell embryos recovered surgically 1-3 days after ovulation from 23 Pony mares were mechanically separated and inserted, in various combinations, into evacuated pig zonae pellucidae to make 27 'half' and 17 'quarter' micromanipulated embryos. These were embedded in agar and cultured in vivo in the ligated oviducts of ewes for 3.5-5 days to allow development to the late morula/early blastocyst stage. Subsequent surgical or non-surgical transfer of 13 'half' and 17 'quarter' embryos to mares resulted in 10 established pregnancies, including 2 monozygotic pairs. Surgic...
The Journal of hygieneJune 1, 1984
Volume 92, Issue 3 365-375 doi: 10.1017/s0022172400064585
Gray SJ.Faecal samples from 110 horses, 115 pigs, 111 sheep and 123 cows were examined for the presence of Aeromonas hydrophila, which was also sought in the available drinking water. The overall faecal rate was 11.8%, but significantly more bovine than other samples were found to be positive. There was significant association between the isolation of A. hydrophila from all animal faeces and its presence in drinking water, but this was not found when individual animal groups were analysed separately. An enrichment technique increased the total number of isolates by 77.1%. Strains of differing origins ...
Hart PJ, Squires EL, Imel KJ, Nett TM.Seasonal changes in the hypothalamic-hypophyseal axis were investigated using tissue from 49 light-horse mares, of mixed breeding. Hypothalamic and pituitary tissues were collected at 5 intervals throughout the years 1981 and 1982, representing midbreeding season (July, n = 10), transition out of the breeding season (October, n = 11), midanestrus (December, n = 8), transition into the breeding season (March, n = 10), and again in the following midbreeding season (July, n = 10). The hypothalamic region was dissected into preoptic area, body and median eminence. Gonadotropin-releasing hormone (G...
Heffner HE, Heffner RS.The idea that large mammals localize sounds more accurately than small mammals has been noted frequently and is usually explained by reference to their large interaural distance and the correspondingly broad binaural time (delta t) and spectral (delta fi) differences between their two ears. Sound-localization thresholds for single clicks and 100-ms noise bursts were determined for horses, and the magnitude of the binaural time (delta t) and spectral (delta fi) cues for sound direction were measured on a horse. Although horses have relatively large interaural distances and physically broad bina...
Smith KM, Barber SM.A two year old Thoroughbred gelding, presented with guttural pouch hemorrhage, had the internal and external carotid arteries ligated. Guttural pouch mycosis was detected on endoscopic examination. After one month of topical antifungal therapy, the horse was returned and euthanized because of recurrent epistaxis. A bacterial infection of the guttural pouch with associated ulceration and hemorrhage from the maxillary artery was found at necropsy.A two year old grade gelding had ulceration and hemorrhage from the external carotid artery. Utilizing balloon-tipped catheters and arterial ligation, ...
Bertram TA, Jensen AE.Morphology and function of equine neutrophils were evaluated after combination with contagious equine metritis organism (CEMO) or 1 of 2 CEMO lipopolysaccharides (LPS). The 2 LPS (LPS-a; LPS-p) isolated from the CEMO contained 14- and 16-carbon fatty acids, ketodeoxyoctanate, hexose, and heptose, but were morphologically distinct. Neutrophils exposed to LPS had fewer granules, whereas those exposed to CEMO had more granules than did the controls (phosphate-buffered saline solution). Neutrophil iodination was significantly increased with 10 and 25 micrograms of LPS-a, but not significantly alte...
Beech J, Aguirre G, Gross S.Nuclear cataracts were found in 2 groups of related Morgan horses. The cataracts were finely reticulated central spherical translucencies that sometimes extended to the region of the posterior "Y" suture. The cataracts were not associated with other ocular defects and did not impair vision. In 1 group of 8 horses, 5 were affected; in the other group, 6 of 8 were affected. Although a pattern of inheritance could not be determined, the familial distribution of the cataracts supported the conclusion that the defect was a heritable disorder.
Bernard-Strother S, Mansmann RA, Beckstead C.A 6-month-old Quarter Horse colt, with severe left foreleg lameness of 6 weeks' duration, had swelling of the distal interphalangeal joint and a smaller-than-normal left front foot. Radiographs revealed a nondisplaced, midsagittal, intraarticular fracture of P3, which was treated with an eggbar shoe with 2 quarter clips, and stall rest for 10 weeks. The colt was sound after 10 weeks.
Gonchar MV, Lavrenova GI, Rudenskaia GN, GaÄda AV, Stepanov VM.Using ion-exchange and affinity chromatography and isoelectrofocusing, eight forms of pepsin with pI 1.6, 1.8, 2.1, 2.3, 2.6, 2.8, 3.2 and 3.6, were isolated from horse gastric juice. The molecular weights, amino acid composition, N-terminal sequence and functional activity of these multiple forms were determined. Partial primary structure of tryptic peptides of pepsin with pI 2.3 was investigated. The analyzed partial sequences of the forms with pI 1.8, 2.1, 2.3, and 2.6 have identical structures which differ from the amino acid sequence of pepsin with pI 3.2 by four substituents. In terms of...
Van Amstel SR, Ross M, van den Bergh SS.A case of maduromycosis mycetoma caused by Madurella mycetomatis is reported. The horse presented with multiple subcutaneous swelling over the right scapula. There were no discharging fistulae present. Macroscopically the lesion contained a black granular material embedded in a granulomatous mass. Microscopically large numbers of microcolonies were present containing segmented hyphae. No typical chlamydospores were observed. Cultures yielded a fungus identified as Madurella mycetomatis. Treatment consisted of surgical excision and local treatment with thiabendazole powder.
Strzemienski PJ, Benson CE, Acland HM, Kenney RM.Two groups of 3 mares were inoculated with Haemophilus equigenitalis or Pseudomonas aeruginosa on the 1st day of estrus. Uterine flushing samples were recovered on day 3 of estrus and day 8 after ovulation for each cycle. Mares were killed 22, 25, and 30 days after inoculation with P aeruginosa and 45, 46, and 49 days after inoculation with H equigenitalis. Pseudomonas aeruginosa was recovered from the uterus of 2 mares 48 hours after inoculation. Although the initial flushing sample of 1 of these 2 mares had an increased total protein concentration, there appeared to be little difference betw...
Steiss JE, Forsyth G.The effect of needle electromyography (EMG) on serum creatine kinase (CK) activity was determined, using clinically normal dogs (males and females; n = 8) and horses (females; n = 8). All animals appeared normal on EMG evaluation. Serum CK was measured before and 4, 24, and 48 hours after EMG. Except for a single 24-hour sample in a dog, the animals did not have abnormally increased serum CK activity after EMG. For dogs and horses, mean values were increased, but within normal range at 4 and 24 hours and returned to base-line values by 48 hours after EMG. For dogs, but not for horses, these CK...
Gross TL, LeBlanc MM.The effect of seasonal morphologic variation of equine endometrium on histologic interpretation of periglandular fibrosis was investigated in 5 mares. Endometrial tissue was procured monthly and examined microscopically for the degree of periglandular fibrosis. A prognostic category for each mare was based on the mean number of fibrotic foci per linear field of 5.5 mm. It was found that seasonal changes reflected in endometrial glands and stroma influenced quantitative assessment of fibrosis. This occasionally resulted in a change in the assigned prognostic category. Marked nonseasonal variati...
Hasslinger MA, el-Seify MA.The investigation of 156 donkeys in the area of the veterinary faculty of the Tanta University in Kafr el-Sheikh showed that 49 animals (31.41%) were infected with trematodes, 34 donkeys (21.80%) served as hosts for Gastrodiscus aegyptiacus, 22 (14.10%) were infected with Fasciola gigantica und 7 (4.49%) with both trematodes. 6 of 40 examined horses (15.0%) showed monoinfections with G. aegyptiacus only. Because of the fragmentary knowledge on these paramphistomides of equids, some aspects concerning the morphology, pathology and clinical symptoms, differential diagnosis, occurrence, host spec...
Braganti G.In 1916 Louis Desliens, veterinary practitioner; submitted to the Academy of Sciences a description of a new way of exploring the cardiovascular system: percutaneous catheteri- zation. In 1935 he published the results of thirty years of explorations in hemodynamics mainly in horses: physiology, pathophysiology and pharmacodynamics. The text considers the very pioneering nature of these studies.
Zaruby JF, Livesey MA, Percy DH.This clinical report describes an 8-year-old Thoroughbred mare that was presented for evaluation of a chronic, unilateral nasal discharge. Findings on physical examination, radiology, and video-endoscopy supported a clinical diagnosis of ethmoidal hematoma. After surgical ablation of the mass a defect was detected in the cribriform plate. At necropsy a 1.5 cm aperture was identified in the left cribriform plate allowing direct communication between the fundus of the nasal cavity and the cranium. Histology of the mass identified tissue consistent with an adenocarcinoma. History of profuse epist...
Grabner A, Goldberg M.In a blind study serum and cerebrospinal fluid (CSF) of control horses and of horses in hepatic coma after chronic food intoxication with Senecio alpinus were collected simultaneously and the composition of free amino acids was determined. The hepatic encephalopathy index in serum (less than 1.65) and in CSF (less than 1.11) of liver patients was distinctly less than to the control values in serum (greater than 2.42) and in CSF (greater than 1.49). The serum concentrations of glutamic acid in hepatic coma were elevated five-fold in comparison to the controls. An indication of ammonia decontami...
Woodger K, Stone EA.This article seeks to examine the history of equine surgery at the Ontario Veterinary College (OVC) in the context of the changing horse economy during the first half of the 20th century. We argue that despite the transition to livestock medicine, public health and small animal practice, the horse, especially as a surgical topic, retained a (diminished) place at OVC due to the lucrative new recreational equine market, the deep links between horses and veterinary medicine, and the equine focus for nearly half a century of Dr. W.J.R. Fowler, the College's primary surgical instructor.
Cohen ND, Carey VJ, Donahue JG, Seahorn JL, Harrison LR.Epidemiological and pathological findings of 433 late-term abortions associated with the mare reproductive loss syndrome (MRLS) in central Kentucky were identified by reviewing the records of the University of Kentucky Livestock Diseases Diagnostic Center. The distribution of dates of abortion was clustered during a brief period of time, presumably from a simultaneous environmental exposure. The most common pathological findings were microscopic pulmonary lesions consisting of squamous epithelial cells present in alveoli with or without concurrent infiltration of inflammatory cells (neutrophil...
Wilke K, Weimann M, Jung M, Geldermann H.10 different oligonucleotide probes were evaluated for DNA fingerprinting in horses. Five probes were able to detect polymorphic bands. The probes (GT)(8) , (GTG)(5) and (GGAT)(4) are most informative for individual identification and were used to analyze a population of Hannoveranian horses. The probability that two individuals have the same DNA fingerprint pattern is 1.2 × 10(-8) , 5.2 × 10(-10) and 1.5 × 10(-7) respectively. Using a combination of the three probes, paternity tests were performed with exclusion probabilities between 0.08% and 4%. ZUSAMMENFASSUNG: Oligonukleotide-Sonden fÃ...
Mariotti F, Cuteri V, Takai S, Renzoni G, Pascucci L, Vitellozzi G.Two horses with Rhodococcus equi infection were examined post mortem by an immunohistochemical method (peroxidase-antiperoxidase; PAP) with a monoclonal antibody (Mab 10G5) to the 15-17 kDa antigen of R. equi. One of the horses was also examined bacteriologically, R. equi being isolated in culture. Immunolabelling with this Mab was marked and widespread. On the other hand, the immunohistochemical reactivity of infected macrophages with a polyclonal antibody specific for lysozyme was slight. Thus, Mab 10G5 would appear to be a useful diagnostic reagent in R. equi infection, with or without cult...
Young DW, Smyth GB.The predominant form of gastrin in the antral mucosa of the stomach of virtually all species previously examined is the 17 amino acid peptide little gastrin (G17). This report describes the occurrence in equine antral mucosa of an immunoreactive form of gastrin with elution properties on Sephadex G-50 superfine similar to human unsulfated big gastrin (G34-I). This putative equine big gastrin was a major component of the gastrin immunoreactivity present. A second peak of activity in equine antral mucosa eluted in an identical manner to human little gastrin (hG17-I). Inhibition curves of equine ...
Harrison IW.Cecal torsion in horses is relatively rare. This clinical report describes cecocolic fold hypoplasia, producing increased cecal mobility, as a predisposing cause of cecal torsion in a horse.
Aceto H, Miller SA, Smith G.To determine time to first detection of Salmonella organisms in feces of animals after experimental infection PO and times to onset of diarrhea and pyrexia to evaluate a common method for identifying nosocomial infections on the basis of time of admission and onset of clinical signs (ie, the 3-day criterion). Methods: Meta-analysis. Methods: Cattle, horses, goats, and sheep experimentally infected PO with Salmonella enterica subsp enterica. Methods: Online databases were searched for published reports describing results of experimental infection of cattle, horses, goats, and sheep PO with salm...
Harkins JD, Karpiesiuk W, Lehner A, Woods WE, Dirikolu L, Carter WG, Boyles J, Tobin T.This report evaluates the pharmacological responses, urinary detection and mass spectral confirmation of ropivacaine in horses. Ropivacaine, a potent local anesthetic (LA) recently introduced in human medicine, has an estimated highest no-effect dose (HNED) of about 0.4 mg/site as determined in our abaxial sesamoid block model. Apparent ropivacaine equivalents were detectable by ELISA screening using a mepivacaine ELISA test after administration of clinically effective doses. Mass spectral examination of postadministration urine samples showed no detectable parent ropivacaine, but a compound i...
DePew CL, Thompson DL, Fernandez JM, Southern LL, Sticker LS, Ward TL.Concentrations of prolactin, glucose, insulin, urea N, and total amino acids in plasma of stallions after ingestion of pelleted feed were compared to those after direct gastric administration of water, NaCl, egg albumin, or corn starch (Exp. 1) or water, egg albumin, hydrolyzed casein (Amicase), or a mixture of indispensable amino acids (Exp. 2). Stallions were fed once daily (75% pellet and 25% hay) at 1500 for 30 d. On d 22, 24, 26, 28, and 30, blood samples were collected every 30 min from 1 h before through 4 h after treatment, which occurred at 1100. In Exp. 1, there was a positive secret...
Pohlin F, Edinger J, Jenner F, Egerbacher M.To describe the anatomic and histologic features of the collateral ligaments (CLs) of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in cadaveric limbs obtained from nonlame horses and to compare the histologic findings with the ultrasonographic appearance of the CLs. Methods: Medial and lateral CLs of the MCP and MTP joints of 28 limbs (16 forelimbs and 12 hind limbs) from 9 adult nonlame horses euthanized for reasons unrelated to the study. Methods: 26 limbs of 8 horses were examined by ultrasonography immediately after euthanasia. Postmortem gross and histologic examinat...
Hay AN, Wagner B, Leeth CM, LeRoith T, Cecere TE, Lahmers KK, Andrews FM, Werre SR, Johnson AL, Clark CK, Pusterla N, Reed SM, Lindsay DS, Taylor S....Equine protozoal myeloencephalitis (EPM) is a debilitating neurologic disease affecting horses across the Americas. Gaps in understanding the inflammatory immune response in EPM-affected horses create difficulties with diagnosis and treatment, subsequently negatively impacting the prognosis of affected horses. The purpose of the current study was to evaluate circulating levels of the inflammatory immune marker soluble CD14 (sCD14), in horses with EPM (n = 7) and determine if they differed from healthy neurologically normal horses (n = 6). Paired sera and cerebrospinal fluid (CSF) samples were ...
Neelis DA, Roberts GD.The many advancements in ultrasound technology, including spatial compounding, harmonic imaging, multidimensional and extended field-of-view images, and improvements in transducer capabilities, are used to enhance the ultrasonographic examination of the equine patient. The improvements in software and hardware capabilities help overcome artifacts, improve image quality, and allow better documentation of the examination for follow-up studies. In addition, the ability of smaller, more portable machines to produce better images is ideal for the ambulatory practice setting.
Smyth GB, Brown RG, Juzwiak JS, Swaim SF, Vaughan JT.A vascularized full-thickness Estlander flap was used to repair a defect involving approximately 40% of the left lower lip of a colt. Postoperative problems were (1) providing nutritional support, (2) minimizing movement at the surgical site, and (3) partial wound dehiscence resulting in a salivary fistula. The surgical site healed well and the colt was left with a fully functional and cosmetic lower lip.
