Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
The Veterinary clinics of North America. Equine practice.
Publisher:
W.B. Saunders,
Frequency: Three no. a year
Country: United States
Language: English
Start Year:1985 -
ISSN:
0749-0739 (Print)
1558-4224 (Electronic)
0749-0739 (Linking)
1558-4224 (Electronic)
0749-0739 (Linking)
Impact Factor
1.1
2022
| NLM ID: | 8511904 |
| (DNLM): | SR0053812(s) |
| (OCoLC): | 11078671 |
| LCCN: | sn 84006968 |
| Classification: | W1 VE929F |
Upper respiratory causes of exercise intolerance. The respiratory system is a frequent cause of exercise intolerance in performance horses. Labored breathing, fatigue during performance, and prolonged recovery after exercise are common complaints. Inadequate fitness level and diseases of the cardiovascular system are differential diagnoses that share these complaints and should be ruled out. Generation of increased airway noise is a clinical sign that implicates the upper respiratory system. A careful history from the owner and endoscopy of the upper airway are the most useful diagnostic tools. Endoscopy during exercise on a treadmill is indi...
Lower respiratory tract disease. Lower respiratory tract disease is an important source of poor performance and exercise intolerance in racehorses and middle-aged sport horses. Horses that perform high-intensity exercise are predisposed to development of infectious and noninfectious respiratory disease. Diagnostic aids for investigation of lower respiratory tract disease include thorough thoracic auscultation with rebreathing, endoscopic examination, bronchoalveolar lavage (BAL), and thoracic radiographic examination. The therapeutic approach for horses with lower respiratory tract diseases often can be directed by cytologic ...
Metabolic causes of equine exercise intolerance. Metabolic causes of exercise intolerance can be subtle and difficult to document in horses. Because of increased metabolic rate in exercising muscle, most metabolic causes of exercise intolerance are clinically manifested by muscle abnormalities such as ER. Newer causes of ER are being documented by current research and are summarized in the article on muscular causes of equine exercise intolerance. Endocrine causes of exercise intolerance have been poorly documented, but recent work has shown the detrimental effects of hypothyroidism on exercise tolerance in horses. Many metabolic manifestati...
Skeletal origins of exercise intolerance in horses. Skeletal origins of exercise intolerance and performance failure can reside in multiple tissues. Diagnosis of injury that results in an ability to continue to exercise, yet inefficiently do so, requires familiarity with evaluation of subtle lameness and often with the specific demands of the different equine sports. Imaging is usually vital to diagnosis development and understanding of lesion influences on locomotion. Therapy is lesion dependent. Return to competitive exercise and performance is dictated by an understanding of skeletal tissue response to injury, rational progressive treatment,...
Exercise intolerance in endurance horses. Endurance competition requires synchronism and development of metabolic and musculoskeletal systems. An understanding of the existence of performance-limiting factors may permit the detection of exercise intolerance that could lead to performance failure, fatigue, and exhaustion. New concepts for assessment of fitness have increased the understanding of individual capacities and deficiencies and the interaction of the different systems involved in exercise.
Diagnostic approach to exercise intolerance in racehorses. The diagnostic approach to the exercise intolerant racehorse depends on sound, fundamental steps to allow complete examination of the entire horse in a logical, time-efficient fashion. Availability of referral diagnostic modalities should not overshadow the need for collecting a clinical history or performing a complete physical examination. The diagnostic approach to exercise intolerance can be divided into a few basic steps. The first step, conducted without the horse, is a thorough discussion about the horse with the trainer and/or owner. Many clinical histories are complex and therefore fo...
Cardiovascular causes of exercise intolerance. Exercise intolerance, due to cardiovascular disease in horses, may be caused by cardiac arrhythmias, valvular regurgitation, congenital abnormalities, myocardial dysfunction, pericardial disease, and vascular thrombosis. The most common cardiovascular cause of exercise intolerance in horses is atrial fibrillation. Cardiovascular abnormalities such as cardiac arrhythmias or murmurs, however, are common in athletic horses and are not always associated with exercise intolerance. Use of an electrocardiography (during rest and exercise) and echocardiography may be necessary to better determine the ...
Muscular causes of exercise intolerance in horses. The muscular system of the horse is remarkable in its athletic scope and capacity to adapt to the demands placed on it. Muscular fatigue often causes exercise intolerance in horses as a primary muscular dysfunction or secondary to abnormalities in other integrated systems such as the cardiovascular, respiratory, or skeletal system. This article reviews basic muscular physiology leading to a discussion of the physiologic causes of muscular fatigue. In addition, a review of pathologic muscle disorders such as muscle strains and exertional myopathies that lead to poor performance is provided.
Instrument sterilization, skin preparation, and wound management. Recent advances in instrument sterilization include the introduction of gas plasma sterilization and the increased use of glutaraldehyde. Gas plasma sterilization has the advantages of no toxic residue effects, reduced turnover time, and applicability for sterilization of heat- and moisture-sensitive instruments. Chlorhexidine gluconate (4%) appears to be a superior preoperative surgical scrub for both the surgeon and the patient because of its increased antimicrobial efficacy, residual activity, and minimal tissue reactions. There are many new wound dressings and topical medications for treat...
Instrumentation and techniques in locomotion and lameness. The success of a clinical gait laboratory depends on choosing the right equipment, installing it correctly, running calibration checks, and having skilled technical and professional personnel. For kinematic analysis, videographic or optoelectronic systems are the method of choice, with 2-D data being adequate for the majority of equine evaluations. A force plate provides a precise description of the 3-D ground reaction force; transmission of the force through the body tissues is measured using strain gauges attached to the bones and tendons. Accelerometers bonded to the hoof wall provide infor...
Instrumentation and techniques in equine fracture fixation. In recent years fracture fixation in the horse has changed significantly. New devices, mainly adapted from the human field, have been successfully introduced into large animal surgery. Examples of such implants include the DCS/DHS implant system, the self-tapping screw, the cannulated screw, and the pinless external fixator. However, new devices have also been developed exclusively for equine fracture management, including the interlocking intramedullary nail and the external skeletal fixation device. With these devices the surgeon has more options for repairing fractures in horses. Neverthele...
Instrumentation and techniques in transendoscopic upper respiratory tract laser surgery. Transendoscopic laser surgery provides equine surgeons with a safe, reliable, and minimally invasive method of performing many surgical procedures in the upper respiratory tract. Although the Nd:YAG laser has proven efficacy, other newer lasers such as the diode and holmium: YAG lasers may prove to be useful tools for equine upper respiratory tract surgery. Long grasping forceps and a high quality fiberoptic or video endoscope are critical components necessary for performing transendoscopic laser surgery. For many of the most common upper respiratory tract abnormalities, a laryngotomy can be e...
Surgical materials and wound closure techniques. Recent innovations in surgical materials have helped to enhance wound healing and protect surgical wounds from infection. Materials such as polyglyconate have been evaluated in equine tissues and found efficacious. Other materials, such as poliglecaprone 25, appear to have qualities useful to equine surgery but are untested in equine tissues. Care must be taken to fully evaluate a new surgical material because its usefulness in equine tissues may not match that in human or laboratory animal tissues. Furthermore, use of disposable materials in surgery, although considered ideal for maintenance ...
Advances in equine arthroscopy. Surgical procedures completed under arthroscopic guidance have become commonplace in many equine practices and have largely replaced surgery using arthrotomy incisions. With a limited amount of equipment, numerous diagnostic and surgical procedures can be completed. Surgeons need to become familiar with regional and intraarticular (intrasynovial) anatomy to ensure that proper surgical approaches are used, access to the lesion will be realized, and potential complications will be minimized. Specialized motorized instruments and surgical lasers are now available and may be useful in the treatmen...
Instrumentation and techniques for carbon dioxide lasers in equine general surgery. The carbon dioxide laser has become an important surgical instrument in human and veterinary medicine. The unique properties of this laser make it the instrument of choice for precise incision, coagulation, and vaporization of tissue at the body surface with minimal morbidity to the patient. This article describes the instrumentation and techniques used to perform a variety of equine general surgical procedures with the carbon dioxide laser. The benefits of surgery using the carbon dioxide laser include precise dissection with minimal trauma to adjacent tissues, good hemostasis, and the abilit...
Instrumentation and techniques for treating orthopedic infections in horses. Orthopedic infections-those involving bones, joints, tendon sheaths, or bursae-are some of the most difficult problems for equine surgeons to treat successfully. Sources of the infection are usually hematogenous, traumatic, or iatrogenic and knowledge of the most likely causative bacteria is very useful in selecting the most appropriate antimicrobial(s) to either prevent or treat these infections in horses. This article discusses the clinical findings, diagnosis, treatment, and prevention of orthopedic infections in horses. More recent treatment methods such as synovial drainage techniques (ar...
Instrumentation and techniques in equine gastrointestinal surgery. Recent advances in abdominal surgical techniques in the horse have resulted in improved survival rates and reduced postoperative morbidity. The development of abdominal surgical procedures in horses has paralleled the development of safe anesthetic protocols and innovative technological advancements in humans. Irrespective of the species, the application of sound surgical principles is still the foundation of surgical intervention. This article describes recent advances in equine gastrointestinal surgical techniques. The availability and application of innovative intestinal surgical devices an...
Instrumentation and techniques for laparoscopic and thoracoscopic surgery in the horse. Equine surgery continues to benefit from advances in laparoscopic techniques. Descriptions of the normal anatomy of the standing horse and advances in instrumentation have improved our ability to perform laparoscopic surgery in both standing and dorsally recumbent horses. The common uses for laparoscopy are diagnostic laparoscopy, cryptorchidectomy, ovariectomy, and diagnostic thoracoscopy. Other reported uses include inguinal hernia repair, ruptured bladder repair, and ventral colopexy.
Instrumentation and techniques in respiratory surgery. In this article, videoendoscopy in conjunction with high-speed treadmill exercise and other specialized diagnostic techniques used to measure upper airway function are reviewed as they pertain to the four most commonly diagnosed functional upper airway obstructions: (1) laryngeal hemiplegia, (2) arytenoid chondritis, (3) epiglottic entrapment, and (4) intermittent dorsal displacement of the soft palate. Using experimental and clinical findings obtained with these new instruments and diagnostic techniques, current recommendations for surgery of these obstructions are presented.
Cryopreservation of equine embryos. Principles and procedures for cryopreservation of equine embryos are described. Embryos less than 250 microM in diameter can be cryopreserved successfully if glycerol is used as the cryoprotectant. Cooling is takes place in such a way that most of the water leaves the cells before intracellular ice forms, and glycerol is removed after thawing without undue osmotic swelling of cells. Vitrification procedures also show promise for small embryos. Satisfactory procedures for cryopreserving embryos of more than 250 microM in diameter are not yet available.
Methods for induction of capacitation and the acrosome reaction of stallion spermatozoa. Methodologies to capacitate bovine spermatozoa, induce the acrosome reaction, and fertilize bovine oocytes in vitro have been established. The capability to do the same with stallion spermatozoa, however, is not available. Several different methods have been used to capacitate stallion spermatozoa with variable results. More basic research needs to be done to establish in vitro conditions necessary to capacitate and induce an acrosome reaction in stallion spermatozoa. Although much progress can be expected in this area, it is unlikely that the general practitioner will use these technologies i...
Use of semen as biopsy material for assessment of health status of the stallion reproductive tract. Conventional light microscopic evaluation does not fully utilize potential indicators in seminal ejaculates for diagnosis of disorders of the reproductive tract. The technique of evaluation of all cellular components of semen, as described in this article, utilizing both light and transmission electron microscopy is a valuable diagnostic tool. Compare with other common biopsy procedures, use of semen as biopsy material is noninvasive, more representative than excisional biopsy, less expensive, and helps in the longitudinal evaluation after a therapeutic regimen.
Superovulation. Development of a superovulation technique that is successful, safe, and commercially available would revolutionize the equine breeding industry. However, the reality is that ovulation rates for mares following existing superovulatory treatment are much lower than for cattle. This dichotomy has been attributed to the relatively limited area available in the ovulation fossa for ovulation to occur, combined with the large size of the equine preovulatory follicle. In addition, the number of ovulations in the mare may be limited physiologically by the size of the follicular cohort that may be rescu...
Transvaginal aspiration. This article describes in detail the procedures for collection of equine oocytes using a transvaginal ultrasound probe. Success in obtaining oocytes from humans, bovines, and horses are presented. The effect of repeated follicular aspiration of both cattle and horses is reviewed.
Early embryonic development and evaluation of equine embryo viability. Tremendous progress has been made in the development of assisted reproductive techniques that may enhance the reproductive efficiency of the horse. However, techniques that involve the manipulation of oocytes and/or embryos may themselves be detrimental to embryo viability and subsequent development. Therefore, an objective method of assessing viability of embryos before and/or after oocyte/embryo manipulation is desirable. At this time, morphologic evaluation is the most widely used method of determining the viability of equine embryos. Although morphologic assessment of embryo quality will n...
Analysis of stallion semen and its relation to fertility. This article describes some of the basic methodology for conducting stallion semen evaluations. Not all of these assays will likely be conducted on every semen sample collected. Routine evaluations should include determination of semen volume, sperm concentration, and an estimation of the percentage of progressively motile sperm, at a minimum. Other assays can be used if a seminal problem is discerned at the beginning of the breeding season or after a stallion has recovered from an illness or injury. Additionally, laboratory assays are particularly important to conduct on cryopreserved spermat...
Maturation and fertilization of equine oocytes. Equine oocytes obtained either by transvaginal ultrasound-guided follicular aspiration or from slaughterhouse ovaries can be matured in vitro. This generally requires culture in TCM-199 containing serum and hormones for 30 to 36 hours. With this protocol, approximately 50% to 60% of the oocytes are at metaphase-II at the end of the culture period. At least some of these oocytes appear viable based on production of fertilized eggs either through in vitro fertilization or fertilization in vivo of a recipient mare. The success of producing equine embryos in vitro is still extremely low. More than...
GnRH therapy for subfertile stallions. Poor fertility has been associated with hormonal imbalances in the stallion. The primary cause of this imbalance is unknown, but it may be related to abnormal gonadotropin secretion. Secretion of GnRH from the hypothalamus causes the release of LH and FSH from the anterior pituitary and these gonadotropins help maintain adequate steroid levels so that normal spermatogenesis can occur. Hypogonadotropic hypogonadism has not been documented in the stallion; however, GnRH therapy has improved the fertility of a limited number of horses. Downregulation of the HPT axis readily occurs in most other s...
Cryopreservation of stallion spermatozoa. The main advantage to using frozen semen in any breeding program is faster genetic gain for the inherited trait desired. Milk production of dairy cows doubled (from 26,000 to 52,000 kg of milk/cow per year) between 1950 and 1980, because the dairy industry was using semen only from bulls with the greatest genetic potential for milk production. This genetic gain could have been achieved without the use of frozen semen; however, the time required to achieve that same genetic progress would have been lengthened exceedingly. Fertility rates using frozen stallion spermatozoa are not equal to that o...
Use of transvaginal ultrasound-guided puncture for elimination of equine pregnancies. Twinning is a major cause of abortion in mares. Although early management of twins is quite successful, twins that remain after 40 days are difficult to manage. This article reviews the current knowledge of the use of transvaginal ultrasound probe for elimination of twins. Several techniques are presented, as well as discussion on the best time during gestation for this technique to be used.
