bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic colic in the mature horse: A retrospective review of 106 cases
Authors: MAIR T. S. , HILLYER M. H. 
Published: April 2010

SummaryThe clinical features of 106 horses presenting with chronic colic examined over a 5 year period were reviewed. Chronic colic was defined as colic signs observed, daily for 3 days or longer, except when masked by analgesics. The diagnosed causes of chronic colic included colonic impaction (31%), peritonitis (16%), enteritis/colitis (7%), colonic displacement/torsion (6%) and lymphosarcoma (4%). A variety of other diseases were diagnosed in a small number of cases, including intestinal adhesions, ileal obstructions, grass sickness, liver disease, caecal impactions, thromboembolic disease, intussusceptions etc. No diagnosis was reached in 8% of cases. Diagnosis was relatively easily achieved in most cases of colonic impaction and peritonitis by results of transrectal palpation and evaluation of peritoneal fluid. Specific clinical features, transrectal palpation, abdominal paracentesis and laboratory evaluations of blood were helpful in the diagnosis of some of the other diseases, but exploratory laparotomy remained necessary in a few cases to achieve a diagnosis.
Recurrent colic in the mature horse: A retrospective review of 58 cases
Authors: HILLYER M. H. , MAIR T. S. 
Published: April 2010

SummaryThe clinical features of 58 horses presenting with recurrent colic examined over a 5 year period were reviewed. The horses were categorised into 3 groups on the basis of the history of colic episodes. Recurrent transient colic Group 1 was characterised by 3 or more episodes of transient colic (of apparently similar type) occurring within one month. Recurrent transient colic Group 2 was characterised by 3 or more episodes of transient colic occurring within one year. Recurrent prolonged colic was characterised by 3 or more episodes of prolonged colic occurring within one year.Fifteen horses were classified as recurrent transient colic Group 1. This group had the highest mortality rate 53%. They included 3 horses with lymphosarcoma, 2 with intussusceptions, 2 with thromboembolic disease/verminous arteritis and 2 with partial ileal obstructions. The recurrent transient colic Group 2 comprised 27 cases with a mortality rate of 4%. Nine of these horses were affected by spasmodic colic. The recurrent prolonged group involved 16 horses with a mortality rate of 31%. These included 3 cases of recurrent colonic impaction and 2 cases each of lymphosarcoma, 2 thromboembolic disease, 2 partial ileal obstructions and 2 intestinal adhesions.
Effects of omeprazole on healing of naturally‐occurring gastric ulcers in Thoroughbred racehorses
Authors: MURRAY M. J. , HAVEN MICHELLE L. , EICHORN EVELYN S. , ZHANG DONGHUI , EAGLESON JANE , HICKEY G. J. 
Published: April 2010

SummarySeventeen Thoroughbred horses with moderate to severe gastric ulceration were purchased from a race track within 10 days of racing and were treated once daily with either omeprazole (9 horses) or vehicle (8 horses) and evaluated gastroscopically for ulcer healing. Horses were administered omeprazole (1.5 mg/kg bwt/day) or vehicle by nasogastric tube once daily. Gastroscopic examination was performed on Days 0, 4, 7, 11, 14, 17, 21, 24 and 28, until lesions healed completely. Selected images of gastric lesions were captured by computer at each endoscopic examination, with a measuring caliper included in captured images. The area and perimeter of lesions were measured by computer and healing rates of specific lesions were determined by calculating the rate of linear advance of the margins toward the centre of the lesion. Additionally, the number of days to complete healing of the entire gastric squamous mucosa was compared between treatment groups. Gastric lesions healed at a significantly faster rate in horses receiving omeprazole than in vehicle‐treated horses (P<0.001). Complete healing of the entire stomach occurred in 10–21 days in omeprazole‐treated horses, and 14–28 days in 3 of 8 vehicle‐treated horses, with the remaining vehicle‐treated horses having unhealed lesions on Day 28. In addition, 5 vehicle‐treated horses developed new lesions in the squamous epithelial mucosa during the trial; no new lesions were observed in the omeprazole‐treated group.
Prospective study of equine colic risk factors
Authors: TINKER MARY K. , WHITE N. A. , LESSARD P. , THATCHER C. D. , PELZER K. D. , DAVIS BETTY , CARMEL D. K. 
Published: April 2010

SummaryA1 year prospective study was conducted on 31 horse farms to identify risk factors for equine colic. Farms were randomly selected from a list from 2 adjacent counties of Virginia and Maryland, USA. The association between colic and farm or individual horse risk factors related to management, housing, pasture, use, nutrition, health and events was first examined by univariate statistical analysis. Individually significant (P<=0.25 for farm factors, P<=0.10 for horse factors) variables were used in a stepwise multivariable forward logistic regression to select explanatory factors (P<=0.05). Analysis was conducted at 2 levels: farm and individual horse with farm specified as a random effects variable. No farm‐level variables were significant Significant horse‐level variables included: age, odds ratio (OR)=2.8 for horses age 2–10 years compared to <2 years; history of previous colic, OR=3.6 relative to no colic; changes in concentrate feeding during the year (1 per year, OR=3.6, more than 1, OR=2.2) relative to no changes; more than 1 change in hay feeding during the year, OR=2.1 relative to no changes; feeding high levels of concentrate (>2.5 kg/day dry matter, OR=4.8, >5 kg/day dry matter, OR=6.3) relative to feeding no concentrate; and vaccination with monocytic ehrlichiosis vaccine during the study, OR=2.0 relative to no vaccination. Feeding a whole grain with or without other concentrate components reduced risk, OR=0.4, relative to feeding no whole grain. Results of the study suggest that diet and changes in diet are important risks for colic in a population of horses on farms.
The effect of age and diet on the oral glucose tolerance test in ponies
Authors: MURPHY D. , REID S. W. J. , LOVE S. 
Published: April 2010

SummaryTo evaluate the effects of age and diet on the oral glucose tolerance test (OGTT) in healthy ponies, OGTTs were performed on 2 groups of British native breed ponies (Group A: 7 foals [6–9 months],Group B: 7 mature individuals [6–13 years]) when maintained on either a high fibre pelleted ration only (Groups AandB) or a hay only diet (Group B). Plasma glucose response, following oral glucose administration, forGroup A(basal plasma glucose concentration [Glu0] 4.6 ± 0.4 mmol/1 (mean ± s.d.) increasing to 11.5 ± 1.3 mmol/1 at 90 min) was significantly different (P<0.05) from that observed forGroup B(Glu0of 4.3 ± 0.2 mmol/1 increasing to 6.8 ± 1.3 mmol/1 at 90 min), when fed the same diet. ForGroup Bponies, the plasma glucose response, following oral glucose administration, was significantly different (P<0.05) when fed hay only (Glu04.6 ± 0.4 mmol/1 increasing to 9.6 ± 2.1 mmol/l at 150 min) compared to when fed the high fibre pelleted ration. These results indicate that both age and diet have a significant effect on plasma glucose concentrations measured during an OGTT.
Technical validation of a face mask adapted for dry powder inhalation in the equine species
Authors: DUVIVIER D. H. , VOTION D. , VANDENPUT S. , ART T. , LEKEUX P. 
Published: April 2010

SummaryDevelopment of dry powder inhalation (DPI) for horses requires the use of an adapted face mask.In experiment 1, 4 masks (A, B, C and D) were tested and factors influencing the delivery of the dry powder were determined. Mask A was one which is commercially available for metered‐dose inhalation. Mask B had the same shape as Mask A but an airtight rubber seal was added for the connection between the mask and horse's head. Mask C was a prototype adapted for DPI with connection for the DPI device between the nostrils, airtight expiratory valves in front of each nostril and an airtight rubber seal to attach the mask on the horse's head. Mask D was the same as Mask C but the airtight expiratory valve was situated in front of one nostril and the connection for the DPI device was placed in front of the other nostril. Inhalet emptying and peak inspiratory pressure were measured on 5 healthy horses with each face mask. Both Masks A and B gave a low rate of inhalet emptying. Inspiratory pressures created in Masks C and D were negative enough to ensure inhalet emptying rates of mean ± s.d. 98.28 ± 1.79% and 100% respectively.Inexperiment 2, the face masks giving the greatest inhalet emptying were used to test the therapeutic efficacy of ipratropium bromide DPI. This was tested on 6 horses suffering from acute exacerbation of chronic obstructive pulmonary disease (COPD). At a dose of 200 μg/100 kg bwt, ipratropium administered with Mask D improved significantly pulmonary function measurements compared to baseline values and placebo inhalation. With Mask C, a double dose of ipratropium (400 μg/100 kg bwt) was necessary to improve these parameters compared to baseline values. This indicated the importance of locating the DPI device in front of one nostril.It was concluded that inhalet emptying is correlated to inspiratory pressures measured in the face masks. Secondly, these pressures are in turn dependent on the airtightness of the mask, i.e. airtightness of the expiratory valve and close connection between the horse's head and the mask. Thirdly, position of the DPI device in front of a nostril allows bronchodilation at a dose half that required when the device is placed between the nostrils. Finally DPI using Mask D (EquiPoudre1) is a rapid, effective and well tolerated inhalation treatment for COPD horses.
Ageing of equine articular cartilage: structure and composition of aggrecan and decorin
Authors: PLATT D. , BIRD J. L. E. , BAYLISS M. T. 
Published: April 2010

SummaryIn order to identify the pathological processes involved in the destruction of articular cartilage in arthritic diseases, it is first necessary to characterise the normal homeostasis of cartilage in a healthy joint. In particular, normal age‐related changes in the biochemistry of cartilage complicate any comparisons that are made between diseased and healthy tissue. There are, however, no reports in the literature detailing the influence of ageing on the biochemistry of proteoglycans in equine articular cartilage. This study addresses the absence of such information by investigating the structure of aggrecan and decorin extracted from a wide age‐range of full thickness equine tissue.The total glycosaminoglycan content of articular cartilage from the metacarpophalangeal joint remained relatively constant throughout life. In contrast, specific components such as hyaluronan increased in concentration with advancing age as did the content of a structural epitope present on keratan sulphate chains. There were also significant age‐related changes in the sulphation pattern of chondroitin sulphate chains. The structure of the large aggregating proteoglycan (aggrecan) became more heterogeneous in size with increasing age and each of the subspecies of aggrecan identified in the extracts was shown to carry a hyaluronan binding region (G1) domain. All subspecies of aggrecan also expressed specific epitopes to keratan sulphate, chondroitin‐4‐sulphate and chondroitin‐6‐sulphate glycosaminoglycan chains. The structure of the small nonaggregating proteoglycan decorin and the aggrecan stabilising molecule link protein were demonstrated to be similar in size and charge to that reported for other species.
The effects of partial thyroidectomy on the development of the equine fetus
Authors: ALLEN A. L. , FRETZ P. B. , CARD C. E. , DOIGE C. E. 
Published: April 2010

SummaryA syndrome of congenital hypothyroidism and dymaturity has been an important cause of reproductive loss and foal mortality in western Canada. The cause and pathogenesis of this syndrome is under investigation. One issue to be addressed is whether all the anomalies present in affected foals are produced concurrently by the same agent, or if affected foals are primarily hypothyroid in utero which induces the associated lesions. This study was designed to document the effects of fetal thyroidectomy, at about 215 days of gestation, on the growth and development of the equine fetus and to compare the anomalies present to those reported in the spontaneously occurring syndrome of foals in western Canada.Two sham‐operated controls and 4 partially thyroidectomised foals were carried to term following surgery. Sham‐operated control foals were normally developed. Partially thyroidectomised foals were hypothyroid; had hyperplastic thyroid gland remnants; abnormal behaviour and locomotor skills; and numerous, marked deficiencies in their skeletal development. The anomalies present in partially thyroidectomised foals were comparable to those reported in congenitally hypothyroid neonates of other species, including human infants, and were similar to those described in congenitally hypothyroid and dysmature foals reported in western Canada.
Exercise‐related alterations in crimp morphology in the central regions of superficial digital flexor tendons from young Thoroughbreds: a controlled study
Authors: PATTERSON‐KANE J. C. , WILSON A. M. , FIRTH E. C. , PARRY D. A. D. , GOODSHIP A. E. 
Published: April 2010

SummaryInjury to the core of the mid‐metacarpal region of the superficial digital flexor tendon in Thoroughbred racehorses is a very frequent but poorly understood condition. It has been suggested that subclinical changes induced by galloping exercise weaken the collagen in this region of the tendon, predisposing it to rupture. The longitudinally arranged collagen fibrils in tendon follow a planar waveform, termed the crimp. Fibril bundles with a smaller crimp angle fail at a lower level of strain than those with a larger crimp angle. This study tested the hypothesis that a specific 18 month exercise programme would result in significant reduction of collagen fibril crimp angle and period length in the core region of the superficial digital flexor tendon of young Thoroughbreds (21 ± 1 months), compared to the normal change in these parameters with age. Central region crimp angle and length were significantly lower in exercised horses than in control horses (P<0.05). The crimp angle was significantly lower in this central region than in the peripheral region of the tendon in 4 of the 5 exercised horses, as was the crimp length in 3 of the 4 horses. The crimp angle in the peripheral region was significantly greater in exercised horses than in the controls (P<0.05), which may indicate functional adaptation due to differing mechanical environment between the 2 tendon regions. The results of this study supported previous evidence that galloping exercise modifies normal age‐related changes in crimp morphology in the core of the superficial digital flexor tendon. Such changes are indicative of microtrauma and would be detrimental to tendon strength.
Survey of anthelmintic resistance on Danish horse farms, using 5 different methods of calculating faecal egg count reduction
Authors: CRAVEN J. , BJØRN H. , HENRIKSEN S. A. , NANSEN P. , LARSEN M. , LENDAL S. 
Published: April 2010

SummaryThis study reports on the prevalence of anthelmintic resistance in strongyles of horses in Denmark. Of 5 methods used for the calculation of faecal egg count reduction (FECR) the method recommended by the World Association for the Advancement of Veterinary Parasitology, for the detection of resistance in sheep was the most sensitive procedure for detecting resistance. Using this method benzimidazole resistance was detected on 33 of 42 farms (79%) examined. Pyrantel was tested on 15 farms and FECR tests indicate resistance on 3 (30%) farms. On 2 farms on which resistance to pyrantel was detected resistance to benzimidazoles was also detected. On one of 16 farms examined ivermectin resistance was indicated at Day 14 but not at Day 19. On the 15 remaining farms ivermectin was effective.Due to the high prevalence of anthelmintic resistance in Danish horse herds it is recommended that tests of anthelmintic efficacy be conducted routinely to monitor the effectiveness of the strongyle control programmes.
Haemodynamic effects of a sixty minute infusion of dopamine hydrochloride in horses anaesthetised with halothane
Authors: YOUNG LESLEY E. , BLISSITT KAREN J. , CLUTTON R. E. , MOLONY V. 
Published: April 2010

SummaryTo describe the haemodynamic effects of a 60 min infusion of dopamine 4 pg/kg bwt/min during halothane anaesthesia, 7 mature Thoroughbred horses were studied. The infusion began 1 h after induction of anaesthesia by romifidine (100 μg/kg) and ketamine (2.2 mg/kg bwt). Throughout the period of dopamine infusion and for 30 min after its discontinuation, the horses were ventilated by intermittent positive pressure to maintain PaCO2between 4.6‐5.4 KPa. Inspired halothane concentration was adjusted to maintain an end tidal halothane concentration of 0.9%. Haemodynamic variables were measured using intracardiac strain gauge transducers sited in the left and right ventricle, aorta, and pulmonary artery. Left ventricular pressure was differentiated to obtain maximal rate of increase of intraventricular pressure (LVdp/dtmax). Transoesophageal Doppler echocardiography was performed to measure maximum aortic blood flow velocity (vmax) and acceleration (dv/dtmax), left ventricular velocity time integral (vTI) and cardiac output (CO), and left ventricular pre‐ejection period (PEP) and ejection time (ET). Measurements were made during the 60 min infusion, and for 30 min after the infusion was discontinued.Infusion of dopamine 4 μg/kg/min significantly decreased mean aortic pressure, while left and right ventricular end‐diastolic pressure and mean pulmonary artery pressure remained unchanged. There was a small, but significant, increase in heart rate during dopamine infusion. Maximum acceleration of aortic blood flow, CO andvTI were also significantly increased by dopamine infusion. Maximal rate of increase of intraventricular pressure (LVdp/dtmax) was significantly decreased 10 min after commencing infusion, but then returned to baseline for the remainder of the study. Left ventricular pre‐ejection period (PEP) decreased during dopamine infusion whilst ejection time (ET) significantly increased. All measured variables except LVET had returned to baseline values within 30 min of discontinuing the infusion.This study demonstrated beneficial effects of dopamine infusion upon left ventricular systolic function. However, the therapeutic value of the drug is likely to be limited in clinical anaesthesia due to the simultaneous falls in arterial blood pressure which accompany its administration.
Increase in blood viscosity in the sprinting horse: can it account for the high pulmonary arterial pressure?
Authors: FEDDE M. R. , ERICKSON H. H. 
Published: April 2010

SummaryBlood was taken from 49 Thoroughbred horses before and after racing at the track to determine if frusemide modified the apparent viscosity of the blood and to determine the effects of changes in shear rate and packed cell volume (PCV), associated with strenuous exercise, on apparent and relative viscosities. Small increases in apparent viscosity of the blood (at a specified PCV and shear rate) occurred in horses given frusemide compared to those receiving no frusemide; however, no differences were seen in relative viscosity. Although 2 groups of horses, those receiving frusemide before racing and those not receiving this drug were studied, the results suggest no infuence of frusemide on any red blood cell variable that might modify apparent blood viscosity. Apparent viscosity of the blood was slightly (but significantly) higher after racing than before racing at any given PCV and shear rate, but relative viscosity was lower in the post race than in the prerace blood sample. The most important contributing factor to the increase in apparent viscosity in blood during racing is the increase in PCV, because the blood becomes nearly shear rate independent at shear rates likely to exist in the cardiovascular system during exercise. With an increase in PCV from 40 to 65% at shear rates above 225/s, apparent viscosity approximately doubled. However, this increase alone cannot account for the elevated pulmonary vascular pressure in the running horse, and additional factors, especially those causing the high left atrial pressure, must be considered. The cause of the elevated pressure may be multifactorial in nature.
Acetaminophen as a marker of gastric emptying in ponies
Authors: DOHERTY T. J. , ANDREWS F. M. , PROVENZA MELANIE K. , FRAZIER DONITA L. 
Published: April 2010

SummaryGastric emptying was evaluated in ponies using the acetaminophen (AP) method. Fifteen minutes after i.v. administration of metoclopramide, erythromycin, yohimbine, atropine or saline, the ponies were given AP by stomach tube. Blood samples for AP analysis were collected at baseline and 15, 30, 45, 60, 75, 90, 105 and 120 min after AP administration. Time to reach peak serum concentration (Tmax), maximum serum concentration (Cmax) and area under the AP serum concentration vs. time curve (AUC) were determined for each treatment group.In the control group, Tmaxwas 31 min and this decreased significantly (P<0.05) following the administration of metoclopramide. Atropine significantly increased Tmaxand decreased Cmaxand AUC. Yohimbine significantly increased AUC. Erythromycin did not significantly change any parameter.This study indicates that acetaminophen can be used to evaluate gastric emptying in ponies. The method is easy to perform and is minimally invasive. Metoclopramide stimulated gastric emptying of liquid in healthy, fasting ponies. Atropine significantly delayed, while erythromycin had little effect on, gastric emptying. Yohimbine increased the cumulative absorption of AP.