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- Author or Editor: Michael W. Ross x
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Summary
Medical records of 28 horses with impaction of the small colon were reviewed; 20 horses were admitted during the winter months. Diagnosis of small-colon impaction was made in 21 horses by rectal examination, and in 7 horses at exploratory celiotomy. Ten horses were treated medically, and 18 were treated surgically. Horses that were treated surgically were more likely to have abdominal distention than were those that responded to medical treatment (P < 0.025). Signs of greater degree of abdominal pain and higher heart rate were seen in horses treated surgically, but these values were not significantly different from values in medically treated horses. Duration of hospitalization was less in horses treated medically (P < 0.025). Long-term survival was higher for horses treated medically (P < 0.025). All horses treated medically and 7 of the horses treated surgically were alive at follow-up evaluation, at least 1 year after discharge. Fever and diarrhea were common complications after surgery. Four horses were fecal culture-positive for Salmonella sp after surgery. Early and aggressive medical management of horses with impaction of the small colon is recommended.
Summary
Medical records of 40 racing Standardbreds with superficial digital flexor tendinitis that underwent transection of the accessory ligament of the superficial digital flexor (sdf) muscle (superior check desmotomy) were reviewed. Surgery was performed bilaterally in 32 horses and unilaterally in 8. Concurrent palmar annular desmotomy was performed in 8 horses in which tendinitis involved the distal metacarpal region and confinement of the deep and sdf tendons by the annular ligament was suspected.
Follow-up information was obtained for 32 horses, by telephone, and racing results were available for 39 horses (1 horse is currently in training, but had a qualifying race prior to surgery). Tendinitis recurred in 8 of 32 (25%) horses that returned to training. Thirty-five of 38 (92%) horses started at least 1 race after surgery. Mean ± sd time between surgery and first race was 237 ± 86 days. Overall, 33 of 38 horses completed 5 or more races after surgery; however, sdf tendinitis recurred in 6, and treatment was, therefore, considered to be successful in 27 horses. Horses started a median of 18 races after surgery. Median amount of money won per start after surgery (median, $418; range, $0 to $4,626) was significantly less than median amount won per start before surgery (median, $1,155; range, $0 to $14,603). Inflammation of the interosseous muscle (Suspensory ligament) developed in 5 horses with bilateral sdf tendinitis and in 2 horses with unilateral sdf tendinitis. All horses with inflammation of the interosseous muscle had undergone bilateral superior check desmotomy.
Objective
To assess the effect of incomplete, midsagittal fractures of the proximal phalanx (P1) on racing performance in Standardbreds.
Design
Retrospective cohort study.
Animals
49 Standardbred horses admitted to the George D. Widener Hospital for Large Animals between July 1986 and December 1992 with a definitive radiographic diagnosis of an incomplete, midsagittal fracture of P1 and a known method of treatment.
Procedure
Performance index and racing time were compared before and after diagnosis and treatment of fracture, using ANOVA that controlled for the effects of horse, gender, age, track length, and track condition.
Results
Expected racing time increased by 0.7 seconds and performance index decreased by 0.7 points, although controlling for factors known to affect racing performance had a substantial impact on these results.
Clinical Implications
Standardbreds with incomplete, midsagittal fractures of P1 have a favorable prognosis for return to racing; recovered horses will likely have slower racing times and decreased performance indices. (J Am Vet Med Assoc 1997;210:82–86)
Abstract
Objective—To evaluate equids with enostosis-like lesions (ELLs) and document the clinical and epidemiological features of this disease.
Design—Retrospective case series.
Animals—79 equids with a scintigraphic diagnosis of at least 1 ELL on ≥ 1 occasion.
Procedures—Medical records of 4,992 equids that underwent bone scintigraphy between March 1997 and March 2009 were reviewed; 78 horses and 1 pony had a scintigraphic diagnosis of an ELL. For those equids, signalment; physical, scintigraphic, radiographic, and lameness examination results; and outcome were reviewed.
Results—Of the 79 equids, 4 (5.1%) had anatomically distinct ELLs on 2 (n = 3) or 4 (1) separate occasions that caused lameness in different limbs. Thus, there were 85 ELL-related admissions to the hospital. Overall, 157 ELLs were detected. Among all equids undergoing scintigraphic examination, Thoroughbreds were more commonly and Standardbreds were less commonly affected. Older animals were more likely to have ELLs. Lameness was directly attributed to scintigraphically evident ELLs in 42 of the 85 (49.4%) admissions. The tibia (62/157 [39.5%]) and the radius (46/157 [29.3%]) were most commonly affected. The ELLs located in the humerus caused more severe lameness than did ELLs in other anatomic locations. Lameness severity was associated with radiopharmaceutical uptake intensity. Among racehorses, those with 1 ELL were more likely to return to racing than were those with multiple ELLs detected in 1 scintigraphic examination; mean interval from diagnosis to first start was 184 days.
Conclusions and Clinical Relevance—Results of this retrospective evaluation of a large group of equids with ELLs have provided a better understanding of this disease process.
Abstract
Objective—To identify scintigraphic abnormalities in the pelvic region of horses examined because of hind limb lameness or poor performance and determine the clinical relevance of areas of abnormal radiopharmaceutical uptake (ARU) in these horses.
Design—Retrospective study.
Animals—128 horses.
Procedure—Medical records were reviewed, and information on signalment, history, admitting complaints, physical examination findings, and results of lameness examinations was recorded. Clinical relevance of areas of ARU was determined by comparison with results of other diagnostic tests. For horses with clinically relevant areas of ARU, follow-up information was obtained through telephone interviews with owners and trainers and analysis of race records.
Results—Areas of ARU were identified in the tuber coxae (25 horses), ischiatic tuber (9), hip joint (10), third trochanter (10), ilium (5), sacral tuber region (22), greater trochanter (1), cranial femoral cortex (1), skeletal muscle surrounding the pelvis (34), or multiple areas (11). In 44 horses, areas of ARU were associated with the primary cause of lameness; in 51, areas of ARU were not associated with the primary cause of lameness; and in 33, the primary cause of lameness was not determined. Thirty-six of the 44 horses with clinically relevant areas of ARU were available for follow-up; 15 (42%) had a good outcome.
Conclusions and Clinical Relevance—Results suggest that pelvic scintigraphy may be useful in identifying abnormalities in horses with hind limb lameness or poor performance. (J Am Vet Med Assoc 2004;224: 88–95)
Abstract
Objective—To determine features of postoperative wound infection caused by Actinobacillus spp in horses undergoing clean, elective surgery and to evaluate bacterial susceptibility profiles of bacteria isolated.
Design—Retrospective study.
Animals—10 horses.
Procedure—Data were retrieved from medical records and the microbiology laboratory database.
Results—1,604 horses underwent clean, elective surgical procedures during the study period. Of these, 23 (1.43%) had postoperative wound infections, and Actinobacillus spp was isolated from 10 of these 23 (43%). Surgical procedures in these 10 horses included laryngoplasty with ventriculocordectomy (n = 3), arthroscopy (3), desmotomy of the accessory ligament of the superficial digital flexor tendon (2), removal of laryngoplasty prostheses (1), and hygroma resection (1). Seven horses survived, and 3 were euthanatized. All 10 Actinobacillus isolates were resistant to penicillin, and 6 were resistant to trimethoprim-sulfamethoxazole. All isolates were susceptible to ceftiofur and gentamicin. During the 5-year period of the study, Actinobacillus organisms were isolated from 35 of 513 (6.8%) samples from the general hospital population submitted for bacterial culture and antimicrobial susceptibility testing.
Conclusions and Clinical Relevance—During the study period, Actinobacillus spp was isolated from a higher than expected percentage of horses that developed postoperative wound infections after clean, elective surgery. Susceptibility profiles for these isolates were different from typical susceptibility profiles for Actinobacillus isolates, suggesting that a pattern of resistance may be emerging. (J Am Vet Med Assoc 2002;221:1306–1310)
SUMMARY
Myoelectric activity of the ileum, cecum, and right ventral colon (rvc) was studied in 4 mature ponies. Eight Ag-AgCl bipolar recording electrodes were sutured to the seromuscular layer of the ileum (2 electrodes), cecum (4 electrodes), and RVC (2 electrodes). Myoelectric activity was studied beginning 10 days after surgery. Eight, 60-minute recording sessions were performed in each pony during the interdigestive period, which was the period 3 to 7 hours after the morning feeding. On separate days, food was withheld for 24 hours, and 90-minute recordings were obtained during the nonfeeding period. Ponies were then fed a normal ration, and recordings were continued to obtain data for the digestive (feeding) period.
All phases of the migrating myoelectric complex were seen at both ileal electrodes during the interdigestive period, including the periods of no spiking activity (phase 1), irregular spiking activity (phase 2), and regular spiking activity (phase 3). Phase 2 occupied 77% of the total recording time, and the mean duration of phases 1,2, and 3 was 3.4 ± 0.2, 12.8 ± 1.2, and 6.7 ± 0.7 min, respectively. Frequency of ileal slow waves was 11.8 ± 0.1/min, and spike burst conduction velocity was 4.7 ± 0.3 cm/s. A complete migrating myoelectric complex was seen in 11 of 32 tracings (34%) and had a mean duration of 24.2 ± 2.6 min. The ileal migrating action potential complex, most often seen in phase 2, had a frequency of 4.8 ± 0.5 spike bursts/h and a conduction velocity of 13.6 ± 0.4 cm/s. The migrating action potential complex was detected directly before retrograde cecal myoelectric activity 73% of the time, indicating possible myoelectric coupling of the ileum and cecum.
Motility patterns recognized in the cecum included: pattern I, spike bursts beginning at the apex and conducted to the cranial base; pattern II, spike bursts beginning at the caudal base and conducted to the apex; pattern III, spike bursts beginning at the cranial base and conducted to the apex; and pattern IV, termed the progressive pattern, beginning at the cecal apex, conducted through the cecal base and cecocolic orifice and into the RVC. The progressive pattern was detected at a frequency of 34.2 ± 1.8 spike bursts/h and was often preceded by (71%), followed by (64%), or preceded and followed by (51%) pattern I or II. This recurring sequence of cecal myoelectric events was termed the cecal myoelectric complex.
In the RVC, 2 patterns of myoelectric activity were seen: aborally directed propulsive spike bursts (3.6 ± 0.6 spike bursts/h) and orally directed retropulsive spike bursts (7.2 ± 1.2 spike bursts/h), confirming that propulsion and retropulsion exist in the RVC.
Nonfeeding caused a significant decrease in the frequency of ileal migrating action potential complex (P = 0.008), cecal pattern III (P = 0.003), and the progressive motility pattern (P = 0.003). Nonfeeding caused a significant decrease (P ≤ 0.009) in the appearance of the cecal myoelectric complex. Feeding caused a significant increase (P = 0.003) in the mean frequency of the progressive pattern compared with the nonfeeding period, but this was significantly less than during the interdigestive period (P = 0.003).
