Mucosal Colonic Biopsies for Diagnosis of Subclinical Colitis in Callitrichids Kept in a Zoo Collection
Spontaneous colitis is a major cause of poor welfare and premature death of captive New World primates of the family Callitrichidae (tamarins and marmosets), particularly cotton-top tamarins (Saguinus oedipus) and common marmosets (Callithrix jacchus) kept in research colonies. By contrast, the prevalence and significance of colitis in callitrichid species kept in zoo collections are not well documented.
Diagnosis of colitis is based on clinical signs in late stages; however, subclinical disease is often found only during routine postmortem examination.3-5 Colonic mucosal biopsies have been extensively used as a research tool for studies aimed at determining the progression of colitis and response to therapeutic interventions in research colonies.1,2 The purpose of this study was to evaluate callitrichids kept at the Henry Doorly Zoo for subclinical colitis by using colonic mucosal biopsies.
Materials and Methods
Colonic mucosal biopsies were obtained from 12 callitrichids. Seven animals were tamarins: one cotton-top (Saguinus oedipus), one Geoffroy’s (S. geoffroyi), two golden lion (Leontopithecus rosalia), three moustached (S. labiatus thomasi). The other five animals were marmosets: four black tufted ear (Callithrix penicillata), and one common (C. jacchus) housed in various exhibits at the Henry Doorly Zoo between January and April 2004. The sex ratio (male:female) was 4:3 for tamarins and 4:1 for marmosets.
A physical examination, tuberculin test, and a blood sample for determination of physiologic parameters were done immediately before the procedure. Endoscopy was performed using a flexible ureteroscope (3.5–4.0 mm; Karl-Storz). Anesthesia was induced with 7% sevoflurane via a mask and maintenance at 3% (Figure 1*). The endoscope was sterilized with gas between each animal. After inserting the ureteroscope rectally, the distance from the anus was recorded, such that mucosal biopsies were obtained from two locations, approximately 3.0 cm and 6.0 cm from the anal ring. The presence of ulcers, erythema, or hemorrhage was recorded. The biopsies were fixed in 10% neutral buffered formalin, embedded in paraffin, cut at 5 µm, and stained with hematoxylin and eosin (H&E) and with Warthin-Starry silver for histopathologic examination.
Results and Discussion
With the exception of a Geoffrey’s tamarin (12412) with chronic soft stool, all monkeys were clinically healthy. The procedure lasted approximately 15 minutes, and no complications such as excessive bleeding or perforation occurred; all the monkeys remained healthy 6 months after the procedure.
The results of histopathologic examination are: one moustached tamarin (MT #8690) had colitis, one Geoffroy’s tamarin (GT #12412) had suppurative exudate without mucosal tissue, whereas the remaining 10 had normal colons (83.3%).
While colitis has been extensively studied in research callitrichids, the disease has not been found in the wild.6,7 Little is known about the prevalence and significance of colitis in callitrichids kept in zoo exhibits. We found that collection of colonic mucosal biopsies was a rapid, safe, and useful technique for identification of callitrichids with subclinical colitis. Repeated colonic biopsies might aid in monitoring disease progression in certain individuals and assess the benefit of specific therapeutic interventions. Because of the ease of performing the procedure, the high risk of subclinical colitis in callitrichid species, and the known impact of the disease on the health and welfare of the animals, collection of mucosal colonic biopsies might be a useful adjunct to routine annual physical examination of zoo callitrichids. Monitoring of zoo callitrichids for colitis would help support responsible conservation of these unique, but either threatened or endangered species.
*VIN editor: Figure 1 was not available at time of publication.
We thank Sarah Dankof, Gerald Hockemeier, Nichole Linafelter, Stephanie Huettner, Eva Restis, Jason Chatfield, Kariny Barrios, Andrea Capobianco, and Francoise Lampen at the Henry Doorly Zoo and the staff at the Veterinary Diagnostic Center at the University of Nebraska-Lincoln for their excellent technical assistance.
1. Clapp, N.K., M.L. Henke, C.C. Lushbaugh, G.L. Humason, and B.L. Gangaware. 1988. Effect of various biological factors on spontaneous marmoset and tamarin colitis: a retrospective histopathologic study. Dig. Dis. Sci. 33(8):1013–1019.
2. Clapp, N.K., A.H. McArthur, R.L. Carson, M.A. Henke, O.C. Peck, and J.D. Wood. 1987. Visualization and biopsy of the colon in tamarins and marmosets by endoscopy. Lab Anim. Sci. 37(2):217–219.
3. Clapp, N.K., M.A. Henke, R.M. Hansard, R.L. Carlson, and R.V. Nardi. 1993. Do repeated colonic mucosal biopsies impact mortality in cotton-top tamarins? In: A Primate Model for the Study of Colitis and Colonic Carcinoma; The Cotton-Top Tamarin (Saguinus oedipus). CRC Press Inc. Pp. 162–167.
4. Chaliofoux, L.V., R.T. Bronson, A. Escajadillo, and S. McKenna. 1982. An analysis of the association of gastroenteric lesions with chronic wasting syndrome of marmosets. Vet. Pathol. 19(Suppl.7):141–162.
5. Leong, K.M., S.P. Terrell, and A. Savage. 2004. Causes of mortality in captive cotton-top tamarins (Saguinus oedipus). Zoo Biol. 23:127–137.
6. Sainsbury, A.W., J.K. Kirkwood, and E.C. Appleby. 1987. Chronic colitis in common marmosets (Callithrix jacchus) and cotton-top tamarins (Saguinus oedipus). Vet. Rec. 121(14):329–330.
7. Wood, J.D., O.C. Peck, K.S. Tefend, M.A. Rodriguez-M., J.V. Rodriguez-M., J.I. Hernandez-C., M.J. Stonerook, and H.M. Sharma. 1998. Colitis and colon cancer in cotton-top tamarins (Saguinus oedipus oedipus) living wild in their natural habitat. Dig. Dis. Sci. 43(7):1443–1453.