To determine the degree of histomorphometric damage in dorsal colon and pelvic flexure biopsy specimens (DCBSs and PFBSs, respectively) obtained from horses with large colon volvulus (LCV) and assess the accuracy of predicting short-term outcome for those horses on the basis of DCBS or PFBS characteristics.
18 horses with ≥ 360° LCV that underwent large colon resection.
During surgery, biopsy specimens from the dorsal colon resection site and the pelvic flexure (when available) were collected from each horse. Interstitial-to-crypt (I:C) ratio (ratio of the lamina propria space occupied by the interstitium to that occupied by crypts), hemorrhage within the lamina propria (mucosal hemorrhage score [MHS] from 0 to 4), and percentage losses of glandular and luminal epithelium were determined in paired biopsy specimens and compared to determine optimal cutoff values for calculating the accuracy of DCBS and PFBS characteristics to predict short-term outcome (survival or nonsurvival after recovery from surgery).
Paired biopsy specimens were obtained from 17 of the 18 horses. The I:C ratio and percentage glandular epithelial loss differed between DCBSs and PFBSs. For DCBSs, an I:C ratio ≥ 0.9 and MHS ≥ 3 each predicted patient nonsurvival with 77.8% accuracy. For PFBSs, an I:C ratio ≥ I and MHS ≥ 3 predicted patient nonsurvival with 70.6% and 82.4% accuracy, respectively.
CONCLUSIONS AND CLINICAL RELEVANCE
Although different, histomorphometric measurements for either DCBSs or PFBSs could be used to accurately predict short-term outcome for horses with LCV that underwent large colon resection, and arguably PFBSs are easier to collect.
Objective—To determine whether omeprazole oral
paste administered at a dosage of 0.5 or 1 mg/kg
(0.23 or 0.45 mg/lb), PO, every 24 hours would effectively
prevent the recurrence of gastric ulcers in horses
in race training.
Procedures—Horses with gastric ulcers were treated
with omeprazole at a dosage of 4 mg/kg (1.8 mg/lb),
PO, every 24 hours for 28 days. Horses in the dose
selection portion of the study were sham dose treated
or received 0.5 or 1 mg of omeprazole/kg, PO,
every 24 hours for an additional 28 days. Horses in
the dose confirmation portion of the study were sham
dose treated or received 1 mg of omeprazole/kg, PO,
every 24 hours for an additional 28 days. Gastric
ulcers were scored before and after the preventive
phase of the study (day 28 to day 56) via gastroscopy,
and ulcer scores were compared.
Results—Sham–dose-treated horses and horses
receiving 0.5 mg of omeprazole/kg had significantly
higher ulcer scores than did horses receiving 1 mg of
omeprazole/kg. There was a significant difference
between the proportion of horses receiving 1 mg of
omeprazole/kg (38/48 [79%]) that remained ulcer free
and the proportion of sham–dose-treated horses
(7/44 [16%]) that remained ulcer free.
Conclusions and Clinical Relevance—Omeprazole
oral paste administered at a dosage of 1 mg/kg, PO,
every 24 hours for 28 days was effective for prevention
of recurrence of gastric ulcers in horses in race
training. (J Am Vet Med Assoc 2005;226:1685–1688)
Objective—To compare efficacy and safety of paste formulations of firocoxib and phenylbutazone in horses with naturally occurring osteoarthritis.
Design—Randomized controlled clinical trial.
Animals—253 client-owned horses with naturally occurring osteoarthritis.
Procedures—Horses were treated with firocoxib (0.1 mg/kg [0.045 mg/lb], PO, q 24 h) or phenylbutazone (4.4 mg/kg [2 mg/lb], PO, q 24 h) for 14 days. Physical examinations and lameness evaluations were performed prior to treatment and after 7 and 14 days. Clinical improvement was defined as a reduction of at least 1 lameness grade or a combined reduction of at least 3 points in scores for pain during manipulation or palpation, joint swelling, joint circumference, and range of motion.
Results—Proportion of horses clinically improved on day 14 for the firocoxib group (104/123 [84.6%]) was not significantly different from the proportion for the phenylbutazone group (103/119 [86.6%]). Proportion of horses that were improved on day 14 was significantly greater for horses treated with firocoxib than for horses treated with phenylbutazone with regard to score for pain on manipulation or palpation (P = 0.028), joint circumference score (P = 0.026), and range of motion score (P = 0.012), but not for overall lameness score or joint swelling score. No direct treatment-related adverse effects were detected during the study.
Conclusions and Clinical Relevance—Results suggested that overall clinical efficacy of a paste formulation of firocoxib in horses with naturally occurring osteoarthritis was comparable to efficacy of a paste formulation of phenylbutazone.