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Case Description—An 8-year-old multiparous Thoroughbred broodmare was admitted for evaluation of a rectal tear sustained during parturition.

Clinical Findings—On initial evaluation, the mare had mild signs of abdominal discomfort. A full-thickness rectal tear located 30 cm cranial to the anus and extending approximately 15 cm longitudinally along the surface of the small colon between the 4 and 6 o'clock positions, when viewed from behind, was diagnosed on examination per rectum.

Treatment and Outcome—Laparoscopic evaluation of the abdomen was performed to assess the tear and extent of peritoneal contamination. A hand-assisted repair via a flank incision was performed. The tear was closed in a single-layer, simple continuous pattern with size-0 polydioxanone with a handheld needle holder. Subsequently, a ventral midline celiotomy was performed, and intestinal contents were evacuated via a pelvic flexure enterotomy and a typhlotomy. Following surgery, the mare was managed with IV fluid therapy, partial parenteral nutrition, antimicrobials, and NSAIDs for 5 to 7 days before being gradually reintroduced to a complete pelleted feed and alfalfa hay. Prior to discharge, examination per rectum revealed no stricture formation associated with repair. The mare was discharged from the hospital and performed successfully as a broodmare, with the delivery of a live foal 1 year after surgery.

Clinical Relevance—Successful repair with an excellent outcome was achieved in this mare. Hand-assisted laparoscopic repair should be considered as a possible treatment option in horses with grade IV rectal tears.

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in Journal of the American Veterinary Medical Association


Cholelithiasis and/or obstructive biliary tract disease was diagnosed ultrasonographically in 8 horses, 5 to 15 years old. Ultrasonographic findings revealed greater than normal amount of hepatic parenchyma in the right side of the abdomen in 8 horses and in the left side in 3 horses. The echogenicity of the liver was greater than normal, and thick distended bile ducts were seen in all horses. Choleliths were imaged ultrasonographically in 6 horses.

Subsequently, postmortem findings in 6 horses revealed periportal and intralobular fibrosis, moderate bile duct dilatation, proliferation, and cholestasis. One or more choleliths were found in all horses. Ultrasonographic findings accurately depicted the histologic changes in the hepatic parenchyma in horses with cholelithiasis.

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in Journal of the American Veterinary Medical Association


Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-Ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxygenation; and (5) anoxia for 30 minutes. Anoxia reduced the accumulation of radiolabeled l-alanine and caused cell swelling, as indicated by an increase in tissue water and tissue Na contents. Reoxygenation improved the tissue's ability to accumulate l-alanine, but tissue swelling continued after this treatment. Tissue Na content and l-alanine accumulation were restored to control values by reoxygenation with superoxide dismutase in the bathing medium. The grade of structural damage, as indicated by separation of eptihelial cells from villi, was equally severe after all, but control, conditions. Superoxide dismutase had no effect on the tissue control conditions. Results of this study suggest that superoxide radicals are involved in the pathogenesis of reperfusion injury in equine jejunal mucosa and that this may be of clinical importance in cases of small intestinal strangulation obstruction.

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in American Journal of Veterinary Research