Equine veterinary journal. Supplement.
Discontinued
Publisher:
Equine Veterinary Journal, Ltd. Hobokken, NJ : Wiley (2009)
Frequency: Irregular
Country: United States
Language: English
Author(s):
British Equine Veterinary Association.
Start Year:1983 - 2013
ISSN:
Impact Factor
2.2
2022
| NLM ID: | 9614088 |
| (DNLM): | SR0062474(s) |
| (OCoLC): | 10429490 |
| Classification: | W1 EQ968 |
The role of the reciprocal apparatus in the hind limb of the horse investigated by a modified CODA-3 opto-electronic kinematic analysis system. The function of the reciprocal apparatus in the hind limb of the horse was studied by kinematic gait analysis. For recording purposes a modified opto-electronic CODA-3 kinematic analysis system was used. The raw kinematic data were corrected for skin displacement artifacts by use of recently developed correction models. It was concluded that contradictory findings about the coupling of tarsal and stifle joints by the reciprocal apparatus, when comparing in vitro and in vivo studies, can be fully attributed to artifacts due to the movement of the skin markers over the underlying bony structures...
Methodology and repeatability of a standardised treadmill exercise test for clinical evaluation of fitness in horses. This paper describes the methodology necessary to perform a clinical exercise test and the expected variability in an individual horse's exercise test measurements based on comparing the results of two repetitions of the test with six horses. The exercise test measurements were obtained with an open flow respiratory gas analysis system, fast time response lactate analyser and an on-board heart rate monitor during an incremental inclined treadmill exercise test. With the exception of peak venous lactate concentration (LACpeak), the results indicate that the mean variability in peak oxygen consu...
Kinetics of VO2 and VCO2 in the horse and comparison of five methods for determination of maximum oxygen uptake. To determine whether maximum oxygen uptake (VO2max) in the horse in influenced by type of exercise test, five different protocols were evaluated in eight untrained Thoroughbreds exercised on a treadmill. With all protocols, horses were given a 5 min warm-up on a 10 per cent treadmill slope. Three protocols were at a 10 per cent slope and included: 1) increasing the running speed by 1 to 2 m/sec every 60 secs from 4 m/sec to a maximum of 12 m/sec; 2) running at 12 m/sec until fatigue; and 3) running for 3 to 4 mins at speeds ranging from 6 to 12 m/sec with rest pauses between exercise bouts. Th...
The effect of an acute angulation of the hind hooves on diagonal synchrony of trotting horses. High speed cinematography was used to measure the timing and distance characteristics of the trot in five sound horses. Two farriery treatments were compared: (1) normal, in which the dorsal hoof wall was aligned with the pastern axis in all four feet and (2) acute hind hoof angulation, in which the hind toes were allowed to grow relatively longer than the heels, so that the angulation was approximately 10 degrees lower than the normal hind hoof angle for the individual animal. Comparison between the two treatments showed that the acute hind hoof angulation was associated with significant incr...
Alterations in plasma volume, plasma constituents, renin activity and aldosterone induced by maximal exercise in the horse. Plasma volume (PV) decreased by 13 per cent following the completion of 1,000 m of maximal exercise in the horse. This study demonstrated that the critical reduction in PV following maximal exercise occurred within 10 mins of completion of exercise, as previously reported in man. Total plasma protein (TPP) increased by 23 per cent at 2 and 5 mins, and by 21 per cent at 10 mins post exercise. Therefore, it does not appear to be an accurate measurement to assess the degree of PV contraction in the horse. Protein was apparently added to the intravascular space either during or following exercise....
Quantification of skin displacement in the proximal parts of the limbs of the walking horse. Displacement of skin over the underlying skeletal structures in the proximal parts of the limbs was investigated in four walking Dutch Warmblood horses. Movement of the skin was visualised with self adhesive spot labels whereas that of the skeletal parts was visualised indirectly by means of a plastic strip connected to a transcutaneous Steinmann pin, driven into the bone of interest. Consistent results for all four horses were found. Individual and mean total displacements ranged from 1 to 4 cm (distal scapula) to 13 to 17 cm (caudal part of the greater trochanter of the femur). Displacements...
Some factors influencing plasma AST/CK activities in thoroughbred racehorses. Sixty-six Thoroughbred horses in training (2 or 3 years of age) were studied during one flat racing season, to investigate the relationship between age, sex, time of year, dietary electrolyte imbalances and plasma aspartate aminotransferase/creatine kinase (AST/CK) activities. Management and training variations were minimised. Between February to October, monthly 24 h post exercise samples were collected and analysed for AST and CK activities. Sex and/or age were shown to have a significant effect on the occurrence of high CK (> 100 iu/litre) and AST (> 300 iu/litre) activities. Fillies ...
A quantitative analysis of skin displacement in the trotting horse. Skin displacement was investigated at 16 sites in the front and hind limbs of four Dutch Warmblood horses at the trot. For visualisation of the bone under the skin, a measuring device mounted on a Steinmann pin driven into the bone under investigation, was employed. Mean displacements ranged from 8 mm (X-displacements proximal and distal metacarpus) to 142 mm (Y-displacement caudal part of greater trochanter). When compared with previously determined skin displacement patterns at walk, mean displacements at trot were of the same magnitude whereas the shape of the time-displacement curve was di...
Cardiorespiratory drift during exercise in the horse. The purpose of the present study was to measure the time-course and degree of cardiovascular and respiratory 'drift' during constant submaximal exercise in the horse. One Thoroughbred and four Morgan mares were instrumented for simultaneous measurement of respiratory and blood gases which also enabled cardiac output (Q) to be calculated. Data were collected at rest, and at 10, 20 and 30 mins during a constant workload which elicited an initial exercising heart rate (HR) of 150 beats/min, and an approximate 15-fold increase in oxygen consumption (VO2). Significant cardiac and respiratory drift ...
Effects of treadmill elevation on heart rate, blood lactate concentration and packed cell volume during graded submaximal exercise in ponies. Six ponies performed a standardised exercise test on a motorised treadmill at each of three randomly assigned treadmill elevations (1, 4, or 7 degrees). The exercise test consisted of four, 4 min increments of increasing treadmill speed from 1.0 to 3.4 m/sec. Heart rate, blood lactate concentration, and packed cell volume (PCV) were determined, during the last min of each exercise level, and at 4 and 12 mins post exercise. Regardless of treadmill elevation, no differences were observed in pre-exercise heart rate (49 +/- 2) beats/min), lactate (1.2 +/- 0.1 mM), and PCV (0.32 +/- 0.01 litres. Du...
Accuracy of formulae for calculating left ventricular volumes of the equine heart. Echocardiography may be an accurate method of measuring left ventricular (LV) volumes and mass of the horse's heart. If so, studies of the heart size and hypertrophy would be possible. This study evaluated geometric models of the external and internal LV shapes, to determine which could be applied to echocardiographic measurements. We preserved 30 horses' hearts and measured their dimensions and cross sectional areas. These measurements were entered into seven formulae representing different geometric models of the ventricle and its chamber. We derived a correction factor to estimate the long ...
Bicarbonate loading in the thoroughbred: dose, method of administration and acid-base changes. Two studies were undertaken in an attempt to investigate the optimal dose, route and time course required to 'bicarbonate load' the Thoroughbred. During the first study a test solution of sodium bicarbonate (NaHCO3) and a control solution of water were administered via a nasogastric tube to six horses. Blood acid-base status was determined immediately prior to and for 24 h following intubation. During the second study a standardised feed was given to four horses, with and without NaHCO3 supplementation. This was followed by a further trial involving the addition of glucose and NaHCO3 to a stan...
Pulmonary artery, aortic and oesophageal pressure changes during high intensity treadmill exercise in the horse: a possible relation to exercise-induced pulmonary haemorrhage. This study investigated changes in packed cell volume (PCV), pulmonary artery and aortic pressures, and the interaction between oesophageal pressure and pulmonary artery and aortic pressures during strenuous exercise in the horse. It was hypothesised that oesophageal pressure changes summate with pulmonary artery and aortic pressures during exercise and contribute to exercise-induced pulmonary haemorrhage (EIPH). Acute treadmill exercise (10 m/sec, 3 degrees incline) produced increases in heart rate (HR) from 50 to 202 beats/min; mean pulmonary artery pressure (PAP) from 28 to 80 mmHg; mean ao...
The effect of an acute hoof wall angulation on the stride kinematics of trotting horses. High speed cinematography was used to describe the stride kinematics in a group of six, sound horses subjected to two farriery treatments, designated 'normal' and 'acute' hoof angulation. Normal was defined as having the dorsal hoof wall aligned with the pastern axis, whereas the acute hoof angulation was approximately 10 degrees lower than the normal angle for the individual horse. The acute angle was achieved by allowing the toes to grow relatively longer than the heels. The results of a multivariate analysis of variance showed significant differences between the two farriery treatments in t...
The physiological basis of training the skeleton. The Sir Frederick Smith Memorial Lecture. The skeleton consists of a series of elements with a variety of functions. In locations such as the skull, where shape or protection are of prime importance, the bone's architecture is achieved during growth under predominant genetic control. In locations such as the limbs, where the ability to withstand repetitive loading is important, only the general form of the bone will be achieved as a result of growth alone, the remaining characteristics resulting from an adaptive response to functional load bearing. In the horse, this functional load-bearing will be provided by the animal's natural act...
Treatment of gastric ulcers in horses with histamine type 2 receptor antagonists. Of 55 horses treated with histamine type 2 (H2) receptor antagonists for gastric ulcers, 32 were examined by gastroendoscopy before and after treatment. Distribution and severity of lesions in the squamous fundus (sf), margo plicatus (mp), glandular fundus (gf), lesser curvature (lc) and cardia (car) were recorded. Severity of the lesions was scored 0-4 (0 = no lesions, 4 = most severe). On initial examination, lesions were most frequently observed at the mp (28/32) and least frequently observed in the gf (5/32). There was endoscopic confirmation of improvement in lesion scores in each region,...
Rectal packing as initial management of grade 3 rectal tears. Grade 3 rectal tears were created in 14 horses. Epidural anaesthesia was maintained in all horses for 8 h post injury. In seven horses with cotton filled stockinette packing the rectum, neither gross faecal contamination nor progression of the rectal tear occurred. Seven horses without rectal packing developed faecal contamination of the rectal tear with formation of a faeces filled serosal or mesorectal diverticulum.
Ultrasonographic evaluation of the healing of ventral midline abdominal incisions in the horse. Ultrasonography was used to evaluate the ventral midline incisions of 21 ponies following exploratory laparotomy. The incisions were evaluated before surgery and at weekly intervals from one to seven weeks after surgery. Both 5.0 and 7.5 MHz linear array and 7.5 MHz sector transducers were used for the evaluations. The incisional complications observed were drainage, oedema, suture sinus formation, suture abscess, superficial dehiscence and incisional hernia. Ultrasonographic imaging of the ventral midline incision was an easy, reliable and objective method for detecting and monitoring the pro...
A device and technique for gastrointestinal lavage in the horse. A device and technique for intra-operative gastro-intestinal lavage was developed to remove ingesta from the stomach, large intestine and caecum of horses. The Gastro-Intestinal Lavage System (GILS) is composed of a nozzle connected to both water under pressure and suction. Water jets across an intake portal in the nozzle, breaks up food and debris within the nozzle and is evacuated under negative pressure into the aspirating tube which is connected to a collection drum. The GILS nozzle was introduced at the pelvic flexure through a sterile enterotomy cuff and plastic sleeve. Water was first a...
The effects of slow infusion of a low dosage of endotoxin in healthy horses. The effects of slow intravenous (i.v.) infusion of a very low dosage of endotoxin (a cumulative dosage of 0.03 microgram/kg bodyweight [bwt] infused over 60 mins) were evaluated in six conscious healthy horses. Duodenal, right ventral colon, and caecal contractions were detected with strain gauge force transducers. Lateral caecal arterial blood flow was measured using transit time ultrasonic blood flow probes. Duodenal contractile activity was not significantly altered by infusion of endotoxin. In contrast, the contractile activity of the right ventral colon 90 and 270 mins after infusion of e...
The effect of Strongylus vulgaris larvae on equine intestinal myoelectrical activity. The myoelectrical activity of the ileum, caecum and large colon was monitored from Ag-AgCl bipolar recording electrodes in four conscious 'parasite-naive' weanling foals. All foals were inoculated with 1000 infective 3rd-stage Strongylus vulgaris larvae and alterations to the myoelectrical activity observed. The frequencies of caecal and colonic spike bursts increased significantly in all post infection periods coinciding with assumed larval penetration into the intestinal mucosa and migration through the vasculature. Peaks in caecal and colonic activity occurred at Days 1 to 5 post infection....
Serum angiotensin converting enzyme activity and response to angiotensin I in horses. The activity of serum angiotensin converting enzyme (ACE) for healthy horses was 64 +/- 13 mUnits/ml. In vitro, equine serum ACE was sensitive to the following inhibitors (IC50): enalapril (570 nM or 215 ng/ml), captopril (190 nM or 41.3 ng/ml), and enalaprilat (6 nM or 2.1 ng/ml). The intravenous (i.v.) administration of angiotensin I to six healthy horses produced a dose proportional pressor response. The maximal increase in mean arterial pressure over baseline values was 65.6 mmHg at angiotensin I doses of 500 ng/kg bodyweight (bwt). The attenuation of this response to angiotensin I was fur...
Observations on the colic motor complex in a pony with a small intestinal obstruction. Characteristic motility patterns were seen throughout the gastrointestinal tract in a pony prepared chronically with electromechanical recording devices after developing a simple obstruction of the small intestine. Gross distension of the stomach with fluid produced loss of gastric contractile activity and a chaotic electrogram. These changes were reversed instantaneously when the stomach was decompressed. In the jejunum, proximal to the obstruction, the unique 'colic motor complex' was observed with contractions of longer duration arranged in characteristic pulses of activity. The left dorsal...
Gastric ulcers in horses: a comparison of endoscopic findings in horses with and without clinical signs. Gastroendoscopic examinations were performed on 187 horses, ranging from one to 24 years. Eighty-seven horses had clinical problems including chronic, recurrent colic for seven or more days (25), one or more episodes of colic within the previous seven days (13), or acute colic (10), diminished appetite (53), poor bodily condition (40), and/or chronic diarrhoea (9). One hundred horses that had no signs of gastrointestinal problems were examined as part of a gastroendoscopic survey. Lesions observed in the squamous fundus, squamous mucosa adjacent to the margo plicatus along the greater curvatur...
Regional gastric pH measurement in horses and foals. The pH of the gastric mucosal surface and gastric content was measured in 18 foals (mean age: 20 days) and 27 horses (mean age: 2.9 years) with a pH electrode passed through an endoscope biopsy channel. A reference electrode was attached to a shaved area on the neck. pH Measurements of the gastric mucosal surface at the dorsal squamous fundus (SF), squamous mucosa adjacent to the margo plicatus (MP), glandular fundus (GF) and the fluid or feed contents of the stomach were recorded in duplicate for each animal. In adult horses, the SF pH was greatest (5.46 +/- 1.82), with a decreasing pH ventra...
Plasma thromboxane B2 levels in horses experimentally infected with Strongylus vulgaris. Plasma thromboxane B2 (TXB2) the stable inactive metabolite of thromboxane A2 (TXA2), was measured daily by specific radioimmunoassay in three groups of animals before and after experimental infection with Strongylus vulgaris. Infection of four 'parasite naive' foals produced a typical acute syndrome with intermittent but statistically insignificant rises in TXB2 levels. Interpretation of results was complicated by the presence of a non-septic peritonitis associated with implantation of the foals with electrodes for recording myoelectrical activity. In two foals of similar age, with some natur...
Antibody titres to core lipopolysaccharides in horses with gastrointestinal disorders which cause colic. Serum immunoglobulin (Ig) titres to core lipopolysaccharide (LPS) were determined in 102 horses admitted to a university referral hospital during a 12-month period for evaluation of colic. Serum samples were collected again 10-14 days later from 84 of the horses. Titres to core LPS were quantitated by an indirect enzyme-linked immunosorbent assay (ELISA), utilising the J-5 mutant of Escherichia coli 0111:B4 as the solid-phase antigen. All horses had natural antibodies to core LPS at the time of admission and the titre was not affected significantly by age, sex or type of gastrointestinal disor...
A study of the effect of isoflurane anaesthesia on equine skeletal muscle perfusion. The effects of 1.1, 1.5 and 1.8 MAC (minimum alveolar concentration) isoflurane-02 anaesthesia on skeletal muscle blood flow, 02 delivery and vascular resistance were studied in the non-dependent region of seven healthy normothermic, isocapnoeic ponies. Muscle blood flow was determined with 15 microns diameter radionuclide labelled microspheres that were injected into the left ventricle. Muscle blood flow during anaesthesia was compared to unanaesthetised (control) measurements. Isoflurane administration caused a dose dependent decrease in mean aortic pressure, and skeletal muscle (temporalis,...
Comparison of detomidine, butorphanol, flunixin meglumine and xylazine in clinical cases of equine colic. Detomidine hydrochloride, butorphanol tartrate, flunixin meglumine and xylazine hydrochloride were evaluated in a blind multi-centre clinical trial in 152 horses with abdominal pain. The drugs were administered as follows: detomidine 20 or 40 micrograms/kg bodyweight (bwt); butorphanol 0.1 mg/kg bwt; flunixin meglumine 1.0 mg/kg bwt; xylazine hydrochloride 0.5 mg/kg bwt. Each centre compared responses to the two doses of detomidine with those to one of the other analgesics. The drugs were administered intravenously (i.v.) after clinical assessment of the degree of sweating, kicking, pawing, he...