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Abstract

Objective—To evaluate use of kinetic gait analysis for detection, quantification, and differentiation of hind limb lameness and spinal ataxia in horses.

Design—Prospective clinical study.

Animals—36 horses.

Procedures—Kinetic gait analysis with a force plate was performed for 12 clinically normal horses, 12 horses with hind limb lameness, and 12 horses with spinal ataxia. Kinetic variables were compared among groups, correlated to subjective grading, and used to build predictive models to assess the accuracy of discrimination.

Results—Subsets of kinetic variables were characteristically altered in ataxic and lame gaits. Ataxic horses had significantly increased lateral force peak and variation in vertical force peaks in both hind limbs. Lame horses had significantly decreased vertical force peak and increased variation in vertical force peaks only in the lame hind limb. These variables were used to differentiate between spinal ataxia and hind limb lameness with excellent accuracy. There were significant correlations between a subset of kinetic variables and subjective lameness and neurologic grades.

Conclusions and Clinical Relevance—Kinetic gait variables, specifically lateral force peak and the variation in vertical force, can be used to support the differential diagnosis between spinal ataxia and hind limb lameness in horses. Kinetic gait analysis may also be applied for quantification of equine hind limb gait abnormalities as well as confirming lack of lameness and ataxia in soundness examinations.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine survival rate and athletic ability after nonsurgical or surgical treatment of cleft palate in horses.

Design—Retrospective case series.

Animals—55 horses with cleft palate.

Procedures—13 of the 55 horses died or were euthanized without treatment and were not included in all analyses. Medical records were reviewed for signalment, history, method of diagnosis, soft or hard palate involvement, type of surgical procedure performed, postoperative complications, and survival to hospital discharge. Information on athletic ability was acquired from race records and follow-up conversations with owners, trainers, or referring veterinarians.

Results—The predominant reason for initial evaluation was milk or feed in the nostrils (60%). The diagnosis was confirmed by means of videoendoscopy of the upper portion of the airway in all cases. Most cases involved the soft palate only (92.7%). Twenty-six of the 55 (47.3%) horses underwent surgical repair, and 12 of these had dehiscence at the caudal edge of the soft palate. Among potential racehorses, 14 of 33 had surgery. Of these, 12 of 14 survived to discharge and 2 horses raced. Among potential racehorses, 10 of 33 were discharged without surgery and 2 of these raced. Among nonracehorses, 12 of 22 underwent surgery and 11 survived to discharge. All horses that were discharged and for which follow-up information was available survived to 2 years of age or older without ill thrift despite dehiscence at the caudal edge of the soft palate and continued mild nasal discharge.

Conclusions and Clinical Relevance—Horses with cleft palate had a higher survival rate than previously reported.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To compare palpation and ultrasound scores of effusion of the medial femorotibial and femoropatellar joints of horses.

ANIMALS

40 horses (80 stifles) were evaluated over a 12-week period.

METHODS

Horses > 1 year of age without history of stifle disease were enrolled from September to December 2022. Palpation of right and left medial femorotibial and femoropatellar joint compartments was performed. Amount of effusion was scored by a board-certified large animal surgeon, a third-year large animal surgery resident, and an equine sports medicine intern. Effusion of right and left medial femorotibial and femoropatellar joints was quantified with ultrasound by a board-certified equine sports medicine and rehabilitation clinician. Amount of effusion on palpation and ultrasound was graded as none-mild (1), moderate (2), or severe (3). A 2-way intraclass correlation coefficient evaluated interrater reliability of palpation scores. The Spearman rank correlation determined association between palpation and ultrasound scores.

RESULTS

Interrater reliability for palpation of effusion was poor between all observers for all joint compartments. No significant correlation was identified between palpation and ultrasound scores for any joint compartment for any observer.

CLINICAL RELEVANCE

Clinicians often rely on palpation of joint effusion as an indication of stifle pathology. We found interrater reliability to be poor for palpation scores, indicating low agreement for palpation of joint effusion between clinicians within our group. No correlation was found between palpation and ultrasound scores for joint effusion, indicating that clinicians should not rely on palpation alone to quantify joint effusion of the medial femorotibial and femoropatellar joints.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To determine sedative, cardiorespiratory and metabolic effects of xylazine hydrochloride, detomidine hydrochloride, and a combination of xylazine and acepromazine administered IV at twice the standard doses in Thoroughbred horses recuperating from a brief period of maximal exercise.

Animals

6 adult Thoroughbreds,

Procedure

Horses were preconditioned by exercising them on a treadmill to establish a uniform level of fitness. Each horse ran 4 simulated races, with a minimum of 14 days between races. Simulated races were run at a treadmill speed that caused horses to exercise at 120% of their maximal oxygen consumption. Horses ran until they were fatigued or for a maximum of 2 minutes. One minute after the end of exercise, horses were treated IV with xylazine (2.2 mg/kg of body weight), detomidine (0.04 mg/kg), a combination of xylazine (2.2 mg/kg) and acepromazine (0.04 mg/kg), or saline (0.9% NaCl) solution. Treatments were randomized so that each horse received each treatment once, in random order. Cardiopulmonary indices were measured, and samples of arterial and venous blood were collected immediately before and at specific times for 90 minutes after the end of each race.

Results

All sedatives produced effective sedation. The cardiopulmonary depression that was induced was qualitatively similar to that induced by administration of these sedatives to resting horses and was not severe. Sedative administration after exercise prolonged the exercise-induced increase in body temperature.

Conclusions and Clinical Relevance

Administration of xylazine, detomidine, or a combination of xylazine-acepromazine at twice the standard doses produced safe and effective sedation in horses that had just undergone a brief, intense bout of exercise. (Am J Vet Res 1999;60:1271–1279)

Free access
in American Journal of Veterinary Research

Abstract

Objective—To indirectly assess the pancreatic response in healthy dogs that were fed diets of different fat compositions with or without supplemental pancreatic enzymes and medium-chain triglycerides (MCTs).

Animals—10 healthy adult dogs.

Procedures—Dogs were fed 4 diets once in random order at 1-week intervals; food was withheld from the dogs for ≥ 12 hours prior to the feeding of each diet. Diets A and B contained 16% and 5% crude fat, respectively; diet C was composed of diet A with pancreatic enzymes; and diet D was composed of diet B with pancreatic enzymes and MCTs. Serum canine trypsin–like immunoreactivity (cTLI) and canine pancreatic lipase immunoreactivity (cPLI) concentrations were measured before (0 hours) and at 1 to 2 and 6 hours after feeding. Serum gastrin concentration was measured at 0 hours and at 5 to 10 minutes and 1 to 2 hours after feeding. A gastrin assay validation study was performed to confirm accuracy of test results in dogs. Data were analyzed by use of a repeated-measures general ANOVA.

Results—Serum cTLI, cPLI, or gastrin concentrations in the dogs did not differ among the different diets fed, among dogs, or over time. When multiple comparisons were analyzed, diet D caused the least amount of measurable pancreatic response, although this difference was not significant.

Conclusions and Clinical Relevance—Results did not indicate a significant effect of dietary fat content or addition of supplemental MCT oil or pancreatic enzymes in diets on serum cTLI, cPLI, or gastrin concentrations in healthy dogs.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate anesthetic effects of 4 drug combinations used for total intravenous anesthesia of horses undergoing surgical removal of an abdominal testis.

Design—Clinical trial.

Animals—32 healthy cryptorchid horses.

Procedure—Horses were sedated with xylazine and butorphanol and were randomly assigned to 1 of 4 groups: induction of anesthesia with ketamine and diazepam and maintenance with bolus administration of ketamine and xylazine (KD/KX); induction and maintenance of anesthesia with bolus administration of tiletamine-zolazepam, ketamine, and detomidine (TKD); induction and maintenance of anesthesia with continuous infusion of xylazine, guaifenesin, and ketamine; and induction and maintenance of anesthesia with continuous infusion of guaifenesin and thiopental. Horses that moved 3 consecutive times in response to surgical stimulation or for which surgery time was > 60 minutes were administered an inhalant anesthetic, and data from these horses were excluded from analysis.

Results—Quality of induction was not significantly different among groups. Muscle relaxation and analgesia scores were lowest for horses given KD/KX, but significant differences among groups were not detected. Horses anesthetized with TKD had a significantly greater number of attempts to stand, compared with the other groups, and mean quality of recovery from anesthesia for horses in the TKD group was significantly worse than for the other groups. Anesthesia, surgery, and recovery times were not significantly different among groups.

Conclusions and Clinical Relevance—Results suggest that all 4 drug combinations can be used to induce short-term anesthesia for abdominal cryptorchidectomy in horses. However, horses receiving TKD had a poorer recovery from anesthesia, often requiring assistance to stand. (J Am Vet Med Assoc 2000;217:869–873)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the items (question topics) for a subjective instrument to assess degenerative joint disease (DJD)–associated chronic pain in cats and determine the instrument design most appropriate for use by cat owners.

Animals—100 randomly selected client-owned cats from 6 months to 20 years old.

Procedures—Cats were evaluated to determine degree of radiographic DJD and signs of pain throughout the skeletal system. Two groups were identified: high DJD pain and low DJD pain. Owner-answered questions about activity and signs of pain were compared between the 2 groups to define items relating to chronic DJD pain. Interviews with 45 cat owners were performed to generate items. Fifty-three cat owners who had not been involved in any other part of the study, 19 veterinarians, and 2 statisticians assessed 6 preliminary instrument designs.

Results—22 cats were selected for each group; 19 important items were identified, resulting in 12 potential items for the instrument; and 3 additional items were identified from owner interviews. Owners and veterinarians selected a 5-point descriptive instrument design over 11-point or visual analogue scale formats.

Conclusions and Clinical Relevance—Behaviors relating to activity were substantially different between healthy cats and cats with signs of DJD-associated pain. Fifteen items were identified as being potentially useful, and the preferred instrument design was identified. This information could be used to construct an owner-based questionnaire to assess feline DJD-associated pain. Once validated, such a questionnaire would assist in evaluating potential analgesic treatments for these patients.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To document clinicopathologic findings in domestic rabbits with liver lobe torsion and identify prognostic factors.

ANIMALS

82 rabbits.

PROCEDURE

Medical records of 4 institutions were reviewed to identify rabbits with an antemortem diagnosis of liver lobe torsion that were examined between 2010 and 2020.

RESULTS

The prevalence of liver lobe torsion was 0.7% (82/11,402). In all 82 rabbits, the diagnosis was made by means of abdominal ultrasonography. Fifty (60.1%) rabbits underwent liver lobectomy, 23 (28%) received medical treatment alone, and 9 (10.9%) were euthanized or died on presentation. Overall, 32 (39%) rabbits died within 7 days of initial presentation and 50 (61%) survived. Seven-day survival rate did not differ significantly between medical treatment alone and surgical treatment. However, median survival time following medical treatment (530 days) was shorter than that following surgical treatment (1,452 days). Six of 14 rabbits had evidence of systemic inflammatory disease on necropsy. Rabbits with right liver lobe torsion were less likely to survive for 7 days than were those with caudate torsions (P = 0.046; OR, 3.27; 95% CI, 1.04 to 11.3). Rabbits with moderate to severe anemia were less likely to survive for 7 days than were rabbits that were not anemic or had mild anemia (P = 0.006; OR, 4.41; 95% CI, 1.55 to 12.51). Other factors associated with a decreased 7-day survival rate were high heart rate at admission (P = 0.013) and additional days without defecation after admission (P < 0.001). Use of tramadol was associated with an increased survival rate (P = 0.018).

CLINICAL RELEVANCE

The prognosis for rabbits with liver lobe torsions was more guarded than previously described. Rabbits that underwent liver lobectomy had a longer median survival time than did rabbits that only received medical treatment.

Full access
in Journal of the American Veterinary Medical Association