Sixteen silver leaf langurs, Trachypithecus cristatus ultimus, developed 22 cases of gastrointestinal linear foreign bodies (GIFB) in 8 yr (1986-1994). Fifty-one langurs older than 6 mo old were present in the colony during this period. Five langurs developed two or three recurrent episodes within 4-12 mo. Eight-six percent of the cases occurred from 1992 to 1994; 82% of the langurs were juveniles (2-6 yr old), and 10 were in three family groups. Seventeen antemortem diagnoses were made, of which 16 required surgery (25% died postoperatively), and one passed the GIFB in the feces. Five postmortem diagnoses were made. Clinical signs included vomiting, anorexia, depression, and abnormal postures suggestive of abdominal discomfort. Palpable intestinal impaction or plication was common. Radiographs, hematology, and serum biochemistry did not contribute to diagnosis. Surgical findings included gastric and/or intestinal foreign bodies. Intestinal perforations and intestinal plication were common. Surgical procedures included gastrotomy, enterotomy, and intestinal resection. Postoperatively, most langurs received i.v. fluids, antibiotics, and flunixin meglumine. Food and water was withheld for the first few postoperative days while i.v. fluids were administered, after which there was a gradual introduction of a normal diet. All five langurs diagnosed at postmortem examination had obstructive GIFB. Four had either abdominal adhesions, peritonitis, intestinal perforation, or plication or some combination of these; one had aspiration pneumonia. Postoperative deaths included two with aspiration pneumonia, one with neurologic disease suggestive of tetanus, and one with massive peritonitis. Foreign body composition was determined by microscopic examination. The majority of the foreign bodies were composed of fibers of screwpine, Pandanus utilis, alone, or with nylon rope. Pandanus utilis were exhibit plants and nylon ropes were in holding areas; both were removed. Due to the fiber length, indigestible nature, and retention in the stomach of both substances, langurs continued to develop obstructions for more than 2 yr after removal of Pandanus and 9 mo after the removal of nylon rope.
