bluuebunny/crossref_metadata_2025_split huggingface dataset:
Post mortem survey of dental disorders in 349 donkeys from an aged population (2005–2006). Part 2: Epidemiological studies
Authors: du TOIT N. , GALLAGHER J. , BURDEN F. A. , DIXON P. M. 
Published: September 2008

Summary Reasons for performing study: Dental disorders have recently been recognised as having major clinical and welfare implications in donkeys. However, no investigation appears to have examined the association of dental disorders with managemental factors and any intercurrent illness. Objectives: To determine the association of dental disorders observed in a post mortem study with age group, body condition score, time since last dental treatment, feeding and the illness that necessitated euthanasia or caused death. Methods: A prospective study documented the type and prevalence of dental disorders in 349 mainly aged donkeys (median estimated age of 31 years) that were subjected to euthanasia over an 18 month period in 2005–2006. The estimated age, body condition score, supplemental feed status, time since last dental treatment and nature of the intercurrent disease that necessitated euthanasia or caused death were also recorded. Multivariable analysis was performed to examine associations of these factors with specific dental disorders and between specific dental disorders. Results: There was a high prevalence (93.4%) of significant dental disease. Age group was significantly associated with the presence of dental disorders and an older age range was a high risk factor for the presence of cheek teeth (CT) diastemata. There was a significant association between the presence of CT diastemata and the concurrent presence of displaced, missing and worn CT. There was also a significant association between the presence of diastemata and colic. Conclusions and potential relevance: Aged donkeys have a high prevalence of dental disorders especially of CT diastemata. Dental disorders and, in particular, the presence of CT diastemata were significantly associated with colic. Routine, prophylactic dental treatments should be performed, especially in aged donkeys.
Equine laminitis: Membrane type matrix metalloproteinase‐1 (MMP‐14) is involved in acute phase onset
Authors: Kyaw‐Tanner M. T. , Wattle O. , Van Eps A. W. , Pollitt C. C. 
Published: September 2008

Summary Reasons for performing study: Enzymatic separation at the hoof lamellar dermal‐epidermal interface may play a role in the development of laminitis and characterising and locating matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of MMPs or TIMPs) in lamellar tissues may further understanding of pathogenesis. Objectives: To clone and sequence the cDNA encoding lamellar MMP‐14 and TIMP‐2, and quantify their transcription in normal and laminitic tissue; and to develop antibody to locate MMP‐14 in lamellar tissues. Methods: Tissue samples were obtained from an oligofructose induced model of laminitis. Total RNA was isolated, amplified by RT‐PCR, cloned into a vector and sequenced. Real‐time PCR was used to quantify MMP‐14 and TIMP‐2 expression. Rabbit anti‐equine MMP‐14 antibody was developed to analyse MMP‐14 proteins from hoof tissues. Results: Immunohistochemistry detected MMP‐14 in the cytoplasm of normal lamellar basal and parabasal cells in close proximity to the lamellar basement membrane. In laminitis affected tissue MMP‐14 immunostaining was depleted in lamellar basal cells. Quantitative real‐time PCR showed MMP‐14 and TIMP‐2 expression significantly (P<0.05) elevated and lowered respectively in laminitis affected tissues. Conclusion: MMP‐14, located in the cytoplasm of normal lamellar basal cells, disappears during laminitis development. The pathology of laminitis is associated with increased and lowered transcription of MMP‐14 and TIMP‐2, respectively. Potential relevance: Enzymes have a role in laminitis pathology and inhibition of their activity may prevent laminitis.
Cartilage‐derived retinoic acid‐sensitive protein in equine synovial fluid from healthy and diseased joints
Authors: BERG L. C. , LENZ J. , KJELGAARD‐HANSEN M. , THOMSEN P. D. , JACOBSEN S. 
Published: September 2008

SummaryReasons for performing study: More sensitive and specific diagnostic methods for early detection of changes in the joint cartilage are needed. Cartilage‐derived retinoic acid‐sensitive protein (CD‐RAP) is a potential marker of cartilage synthesis and regeneration. This is the first study on equine CD‐RAP.Objectives: To evaluate the ability of a commercially available human sandwich ELISA assay to detect equine CD‐RAP in synovial fluid from healthy and diseased joints.Methods: Synovial fluid was collected from 28 horses with no signs of joint disease and from 5 with induced inflammatory arthritis. CD‐RAP concentrations were measured using a human CD‐RAP ELISA. Intra‐ and interassay imprecision of the assay were evaluated by multiple measurements on pools of equine synovial fluid. Assay inaccuracy was determined by linearity under dilution.Results: The assay showed moderate to large intra‐ and interassay variation when applied to equine synovial fluid. Equine CD‐RAP was detected in synovial fluid from healthy horses ranged at 8.2–52 ng/ml. Repeated arthrocentesis (after injection of isotonic saline), age, joint or gender did not significantly affect CD‐RAP concentrations. Twelve hours after intra‐articular injection of lipopolysaccharide, concentrations of CD‐RAP were significantly lower than after injection of isotonic saline and remained significantly lower until the end of the study at 144 h.Conclusion and potential relevance: The assay is suitable for longitudinal monitoring of CD‐RAP concentration in individual horses. Disease significantly influenced CD‐RAP levels. Similar to previous results obtained in man, CD‐RAP seems to be a marker of cartilage synthesis and/or regeneration in horses.
Regionalisation of the muscle fascicle architecture in the equine longissimus dorsi muscle
Authors: RITRUECHAI P. , WELLER R. , WAKELING J. M. 
Published: September 2008

Summary Reasons for performing study: The longissimus dorsi is the largest muscle in the equine back and plays an important role in locomotor ability and performance in the horse. In vivo studies suggest that the mechanical function varies between different muscle segments, in part determined by anatomy. It is possible therefore that variations in function reflect variations in the anatomy of the longissimus dorsi along its length. Objectives: To identify if there are regional variations in muscle architecture of the longissimus dorsi. Methods: Computed tomography scans were obtained from 8 cadaver backs to identify the cross‐sectional area and volume of the muscle. The 3D orientations of the muscle fascicles were quantified in situ by their direction cosines using a magnetic digitisation system. Results: Mean ± s.e. volume of the muscle was 2.34 ± 0.18 l for each side and mean length of the vertebral column from T4 to L6 dorsal spinous processes was 56.57 ± 2.0 cm. There were significant differences in the cross‐sectional area and the moment arm lengths between muscle segments (P<0.05). In the lumbar region, the mediolateral moment arms were 2–3 times greater than the dorsoventral moment arms. There were significant variations in the direction cosines (n = 7129) between muscle segments and between different regions within each segment (P<0.05). Potential relevance: These observations indicate that the muscle fascicle architecture predisposes the longissimus dorsi to different functions both along its length and between different regions within each segment. Detailed 3D anatomical measures of the structure with in vivo measures of function (back motion and muscle activity) will be investigated in further studies.
Mechanical nociceptive thresholds within the pastern region of Tennessee Walking Horses
Authors: Haussler K. K. , Behre T. H. , Hill A. E. 
Published: September 2008

Summary Reasons for performing study: ‘Soring’ is the term used to describe the application of an irritant to the distal forelimbs of gaited horses with the sole intent of inflicting pain and inducing altered gait, illegally practiced in Tennessee Walking Horses. Objective methods for the detection of limb pain due to this practice are, however, lacking. Objectives: To assess whether Tennessee Walking Horses respond to manual pressures ≤10 kg/cm2 and to establish reference mechanical nociceptive thresholds (MNTs) within the pastern region. Methods: In 25 mature Tennessee Walking Horses in which no irritant had been applied, MNTs were evoked by a pressure algometer at 4 sites within the pastern region of each thoracic limb by 6 different examiners. The effects of age, sex, weight, height at withers, exercise and hand dominance of the examiners on MNTs were assessed. Correlations between the horse's perceived mental status, tolerance to the procedure and MNT values were also evaluated. Results: Mechanical nociceptive thresholds ≤10 kg/cm2 were observed in 20% of measurements, of which the mean ± s.d. MNT was 9.5 ± 0.3 kg/cm2. Within 4 pastern sites, the palmar region had the lowest reference MNT value of 19.5 ± 3.6 kg/cm2. Subject status, exercise, hand dominance, horse mental status and horse procedure tolerance did not significantly affect MNT values. Conclusions: Reference MNTs of the pastern region of nontreated Tennessee Walking Horses provide an objective standard for the evaluation of those potentially applied irritant. Potential relevance: Pressure algometry, in lieu of digital pressure, can quantify mechanical pressure applied during inspections to detect irritant therapy and provide consistency between examiners.
Penile and preputial tumours in the horse: A retrospective study of 114 affected horses
Authors: van den TOP J. G. B. , DE HEER N. , KLEIN W. R. , ENSINK J. M. 
Published: September 2008

SummaryReasons for performing study: Preputial and penile tumours are more common in horses than in other domestic animals, but no large surveys of male horses with tumours of the external genitalia are available.Objective: To present a retrospective analysis of male horses with neoplasms of the external genitalia.Methods: The penile and preputial tumours of 114 horses were evaluated. Data recorded included age, gelding or stallion and breed; type and site of lesion; involvement of regional lymph nodes; histopathology (including grading of squamous cell carcinoma); and results of radiographic examination of the thorax.Results: Mean age of horses was 19.5 years with no apparent breed predilection. Common presenting clinical signs were irregularities (e.g. the presence of a mass and/or ulceration) on the integument of the penis and prepuce, and purulent or sanguineous discharge from preputial orifice. Squamous cell carcinoma (SCC) was the most prevalent neoplasm followed by papillomas and melanomas. A basal cell carcinoma, neurofibrosarcoma, adenocarcinoma or fibrosarcoma were each found on single horses. Squamous cell carcinomas with poor differentiation had a higher tendency to metastasise than did more differentiated tumours.Conclusions: Squamous cell carcinoma is the most common urogenital tumour of the male horse and occurs primarily in old horses. Horses with poorly differentiated SCCs tend to have a higher incidence of regional metastases. Pathology of lymph nodes, even when not palpably enlarged, is a valuable diagnostic exercise. Radiology of the thorax to detect lung metastases is of little value.
Effect of paddock vs. stall housing on 24 hour gastric pH within the proximal and ventral equine stomach
Authors: HUSTED L. , SANCHEZ L. C. , OLSEN S. N. , BAPTISTE K. E. , MERRITT A. M. 
Published: September 2008

SummaryReasons for performing study: Stall housing has been suggested as a risk factor for ulcer development in the equine stomach; however, the exact pathogenesis for this has not been established.Objectives: To investigate the effect of 3 environmental situations (grass paddock, stall alone or stall with adjacent companion) on pH in the proximal and the ventral stomach.Methods: Six horses with permanently implanted gastric cannulae were used in a randomised, cross‐over, block design. Each horse rotated through each of three 24 h environmental situations. Horses remained on their normal diet (grass hayad libitumand grain b.i.d.) throughout the study. Intragastric pH was measured continuously for 72 h just inside the lower oesophageal sphincter (proximal stomach) and via a pH probe in the gastric cannula (ventral stomach).Results: Neither proximal nor ventral 24 h gastric pH changed significantly between the 3 environmental situations. Mean hourly proximal gastric pH decreased significantly in the interval from 01.00–09.00 h compared to the interval from 13.00–20.00 h, regardless of environmental situation. Median hourly proximal pH only differed in the interval from 06.00–07.00 h compared to the interval 14.00–19.00 h. Neither mean nor median hourly ventral gastric pH varied significantly with the time of day.Conclusions: The change in housing status used in the current study did not affect acid exposure within either region of the equine stomach. The pH in the ventral stomach was uniformly stable throughout the study, while the proximal pH demonstrated a 24 h circadian pattern.Potential relevance: Since stall housing was not associated with prolonged acid exposure to the proximal stomach, this aspect alone does not explain the increased risk of squamous ulcer development. The circadian rhythm associated with proximal intragastric pH warrants further investigation.
In vitroeffects of hydrochloric and lactic acids on bioelectric properties of equine gastric squamous mucosa
Authors: ANDREWS F. M. , BUCHANAN B. R. , ELLIOTT S. B. , JASSIM R. A. M. AL , McGOWAN C. M. , SAXTON A. M. 
Published: September 2008

SummaryReasons for performing study: Volatile fatty acids, byproducts of carbohydrate fermentation by resident bacteria, have been implicated in causing nonglandular (NG) gastric ulcers. Lactic acid (LA), also produced by stomach bacteria, may cause gastric ulcers when exposed to the equine NG mucosa.Objectives: To investigate thein vitroeffects of LA on equine NG mucosa bioelectric properties, sodium transport and tissue resistance.Methods: Gastric tissues obtained from 13 mature horses were studied in Ussing chambers. Short‐circuit current (Isc) and potential difference (PD) were measured, and electrical resistance (R) and conductance (G) calculated for tissues after addition of HCl and LA (5, 10, 20 and 40 mmol/l) in normal Ringer's solution (NRS).Results: Mucosa exposed to HCl or LA (5, 10 and 20 mmol/l) in NRS (pH 1.5 and to a lesser extent pH 4.0) had a significant decrease in Isc and PD. Mucosa exposed to a high concentration of LA (40 mmol/l) in NRS (LRS) at pH 1.5 showed an increased G, but this increase was not significant. Values returned to baseline after solutions were returned to pH 7.0. Histological changes were consistent with HCl‐induced (pH <4.0) acid damage.Conclusions: HCl induced alteration in bioelectric properties of equine NG mucosa whereas addition of LRS did not, other than those changes seen with HCl alone.Potential relevance: Lactic acid, produced in the stomach of horses fed a high‐grain diet, does not significantly alter sodium transport or permeability in equine NG mucosal tissue. Lactic acid may require a longer exposure time or may need the presence of other VFAs in HCl to cause gastric ulcers.
Validity of indicators of dehydration in working horses: A longitudinal study of changes in skin tent duration, mucous membrane dryness and drinking behaviour
Authors: PRITCHARD J. C. , BURN C. C. , BARR A. R. S. , WHAY H. R. 
Published: September 2008

SummaryReasons for performing study: Dehydration is a serious welfare concern in horses working in developing countries. Identification of a valid and practical indicator of dehydration would enable more rapid treatment and prevention.Objectives: To examine changes in bodyweight, clinical and blood parameters during rehydration of working horses, identify a ‘gold standard’ criterion for dehydration and use this to validate a standardised skin tent test, drinking behaviour and mucous membrane dryness as potential field indicators.Methods: Fifty horses with a positive skin tent test, working in environmental temperatures of 30–44°C in Pakistan, were rested and offered water to drink ad libitum. Bodyweight, clinical and blood parameters, mucous membrane dryness, drinking behaviour and skin tent duration at 6 anatomical locations were measured at 0, 30, 60, 120, 180, 240 and 300 min.Results: Skin tent duration was affected by side of animal (P = 0.008), anatomical location and coat moisture (both P<0.001). Younger animals had shorter skin tents at all time points (P = 0.007). There was no significant association between plasma osmolality (Posm) or water intake and skin tent duration. Horses with a higher Posm drank significantly more water (P<0.001), and had longer (P<0.001) and more frequent (P = 0.001) drinking bouts. Neither Posm nor water intake affected qualitative and semi‐quantitative measurements of mucous membrane dryness significantly.Conclusions and potential relevance: The standardised skin tent test and measures of mucous membrane dryness investigated in this study were not valid or repeatable indicators of dehydration when compared with Posm as a ‘gold standard’ criterion. The volume of water consumed and the number and duration of drinking bouts were the most reliable guide to hydration status currently available for mature working horses. Offering palatable water to drink ad libitum provides both the diagnosis and the remedy for dehydration in working horses.
Racing performance following the laryngeal tie‐forward procedure: A case‐controlled study
Authors: Cheetham J. , Pigott J. H. , Thorson L. M. , Mohammed H. O. , Ducharme N. G. 
Published: September 2008

SummaryReasons for performing study: The laryngeal tie‐forward procedure (LTFP) is becoming widely used for correction of dorsal displacement of the soft palate (DDSP) despite the absence of an evidence‐based assessment of its efficacy.Hypotheses: The LTFP returns racing performance to preoperative baseline levels and to that of matched controls; and post operative laryngohyoid position is associated with post operative performance.Design and population: Case‐controlled study of racehorses undergoing a LTFP for dorsal displacement of the soft palate at Cornell University between October 2002 and June 2007.Methods: The presence of at least one post operative start and race earnings ($) were used as outcome variables. Controls were matched by age, breed and sex from the third race prior to surgery. A novel radiographic reference system was used to determine laryngohyoid position pre‐ and post operatively. Data for definitively and presumptively diagnosed cases were analysed separately.Results: During the study interval, 263 racehorses presented, of which 106 were included in the study; 36 had a definitive diagnosis of DDSP and 70 a presumptive diagnosis. Treated horses were equally likely to race post operatively as controls in the equivalent race. Treated horses had significantly lower earnings in the race before surgery than matched controls. The procedure moved the basihyoid bone dorsally and caudally and the larynx dorsally and rostrally. A more dorsal post operative basihyoid position and more dorsal and less rostral laryngeal position were associated with an increased probability of racing post operatively.Conclusions: Horses undergoing a LTFP are as likely to race post operatively as matched controls. The procedure restores race earnings to preoperative baseline levels and to those of matched controls.Potential relevance: This study provides strong evidence supporting the use of the LTFP in racehorses. Further work is needed to determine the relationship between laryngohyoid conformation and nasopharyngeal stability in horses.
Molecular insights into dietary induced colic in the horse
Authors: SHIRAZI‐BEECHEY S. P. 
Published: September 2008

SummaryEquine colic, a disorder manifested in abdominal pain, is the most frequent cause of emergency treatment and death in horses. Colic often requires intestinal surgery, subsequent hospitalisation and post operative care, with a strong risk of complications arising from surgery. Therefore strategies that explore approaches for preventing the condition are essential. To this end, a better understanding of the factors and mechanisms that lead to the development of colic and related intestinal diseases in the horse allows the design of preventive procedures.Colic is a multifactorial disorder that appears to be induced by environmental factors and possibly a genetic predisposition. One factor that seems to influence the risk of developing colic is the excessive consumption of diets containing high levels of carbohydrates. Therefore, major efforts have been made by various laboratories and institutions across the world to study the type and digestibility of various feed in order to formulate accurate and safe feed components and proportions. However, relatively little work has been carried out to characterise, in detail, the carbohydrate digestive and absorptive capacity and mechanisms underlying the potential adaptive response of equine gut epithelium to a changing diet.This review focuses on advances made towards understanding the molecular and cellular mechanisms involved in digestion and absorption of dietary carbohydrates in the equine gastrointestinal tract and the implication of these processes for the whole body physiology. It addresses the underlying mechanisms that may govern the adaptive response of equine small intestine to increased dietary hydrolysable carbohydrates. Furthermore, it describes changes that occur in the equine large intestinal microbiology and host tissue biology brought about by alterations in diet and in colic. It is hoped that a better understanding of the molecular and cellular processes that play important roles in the physiology and pathology of the equine gastrointestinal tract will assist the development of effective strategies to prevent equine colic.
The use of race winnings, ratings and a performance index to assess the effect of thermocautery of the soft palate for treatment of horses with suspected intermittent dorsal displacement. A case‐control study in 110 racing Thoroughbreds
Authors: Reardon R. J. M. , Fraser B. S. L. , Heller J. , Lischer C. , Parkin T. , Bladon B. M. 
Published: September 2008

SummaryReasons for performing the study: There have been no reports of the efficacy of thermocautery of the soft palate (TSP) assessed objectively as a treatment of intermittent dorsal displacement of the soft palate (DDSP).Objective: To compare: racing performance of horses that underwent thermocautery of the soft palate with matched controls; and ‘Racing Post ratings’ (RPR) with prize money won (RE) and a performance index (PI) for each of the horses in the study.Hypothesis: Thermocautery of the soft palate has no beneficial effect on racing performance and the 3 measures of performance are significantly related.Methods: The inclusion criteria were fulfilled by 110 horses and each was matched with 2 controls. Changes in performance were compared statistically. RPR, RE and PI were analysed using a regression model.Results: The percentage of horses that improved in performance following the procedure was 28–51% for the 3 measures of performance, compared to 21–53% for the matched controls. There was no significant effect of the procedure on the changes in RPR or RE. There was a significant effect of the procedure on the change in PI (P = 0.015) with more treated horses achieving an improved PI and fewer acquiring a worse PI than matched control horses. The measures of performance showed significant correlation.Conclusions: Thermocautery of the soft palate alone may not be the most efficacious treatment of DDSP.Potential relevance: Production of a reliable measure of racehorse performance may be possible.