This case series describes gastrointestinal torsion and intussusception in five northern koalas (Phascolarctos cinereus) aged 2–11 yr at the San Diego Zoo from 1976–2012. Three of the individuals were males and two were females. Two of the animals died shortly after presenting. Diagnosis of an ileocecal intussusception resulting from enteritis in one of these peracute cases and cecal torsion in the other was made at necropsy. Two small intestinal mesenteric torsion and one proximal colon mesenteric torsion case were successfully surgically corrected. The colonic mesenteric torsion case had recurrent clinical signs two weeks later and a second surgery requiring resection and anastomosis of ischemic jejunum was performed, with the koala dying shortly afterwards. One of the small intestinal torsion cases had a recurrence of the torsion 22 mo later and consequently died. The second small intestinal torsion case remains alive 5 mo postsurgical correction. All five koalas presented with signs of colic that included anorexia, lethargy, depression, acute abdominal distension, abdominal stretching, decreased fecal output, and/or open-mouth gasping. Abdominal radiographs in cases of this type may show stacked gastrointestinal linear gas patterns and contrast stasis.1,2 Clinical signs and radiographic changes are indicators that surgical intervention is required. High mortality in koalas with gastrointestinal torsion and intussusception emphasizes the importance of timely recognition and surgical correction.1-4
The authors thank the veterinary, nutrition, and pathology departments along with the koala keepers at the San Diego Zoo for their dedicated care and support of the koala collection. A special thanks to the entire veterinary department and support staff for the student education they have all so graciously provided.
1. Blanshard, W. 1994. Medicine and Husbandry: Koalas. Post Graduate Committee in Veterinary Science, University of Sydney, Sydney, New South Wales. 547–626.
2. Blanshard, W., and K. Bodley. 2008. Koalas. In: Vogelnest, L., and R. Woods (eds). Medicine of Australian Mammals. CSIRO Publishing, Collingwood, Victoria. 227–327.
3. Jackson, S., L. Perry, P. O’Callaghan, D. Spittal, L. Romer, and K. Reid. 1999. Koala Phascolarctos cinereus: Captive Husbandry Guidelines. Available at www.aszk.org.au/docs/koala.pdf [VIN editor: URL could not be accessed as of 12/26/2020] . Accessed July 2012.
4. Pye, G. 2008. AZA Koala SSP Veterinary Manual. Available at http://www.aazv.org/associations/6442/files/aza_koala_SSP_veterinary_manual.doc [VIN editor: URL could not be accessed as of 12/26/2020]. Accessed July 2012.