Irregular Tooth Wear and Longevity in Captive Wild Ruminants: A Pilot Survey of Necropsy Reports

Abstract

Clauss, M; Hatt, J M (2008). Irregular tooth wear and longevity in captive wild ruminants : a pilot survey of necropsy reports. Journal of Zoo and Wildlife Medicine, 39(1):69-75.

Variation in dental wear and tooth loss among known‐aged, older ring‐tailed lemurs (Lemur catta): a comparison between wild and captive individuals

“…Reduced dental health in some captive mammals has been suggested as one factor limiting lifespan among these taxa in captivity [e.g., Clauss et al, 2007;Jurado et al, 2008;Kaiser et al, 2009]. However, given annual veterinary and dental examinations, tooth cleanings, and a controlled diet, we expected less overall tooth wear and few cases of tooth loss in the Indianapolis Zoo ring-tailed lemur population, when compared with the BMSR sample.…”

“…Specifically, we integrated the study of these captive, known-aged lemurs, with controlled diets, annual medical evaluations, dental cleanings, and no predation, to provide a comparative template of patterns of dental wear one might expect in an ''optimal'' population. Although some captive mammals exhibit patterns of tooth wear that exceed those seen in wild populations [e.g., Clauss et al, 2007;Jurado et al, 2008;Kaiser et al, 2009], given their regular medical and dental care, we expected less overall tooth wear and fewer lost teeth in the captive Lemur catta sample when compared with the BMSR population. To our knowledge, ours are the first data comparing dental macrowear between wild and captive similar-aged individuals within a single primate species.…”

“…For example, captive populations of some browsing species (e.g., giraffes, Giraffa camelopardalis) exhibit significantly more tooth wear than their wild counterparts, which is viewed as a product of consuming grass hay and processed foods with high amounts of silica [Clauss et al, 2007, but see Sanson et al, 2007 for a counterargument on silica and tooth wear]. Also, Jurado et al [2008] suggest that severe tooth wear in captive blackbucks (Antilope cervicapra) resulted from husbandry practices, specifically, regularly being fed on sandy soils. In contrast to these herbivorous mammals, Gipson et al [2000] observed a similar pattern of tooth wear between captive and wild wolves (Canis lupus).…”

“…Yet, the degree of loss in this individual (25%) is far less than several lemurs in the BMSR population, including two who are only half the age of ''Junior'' at the Indianapolis Zoo. Jurado et al [2008] noted that few studies have directly assessed the potential link between increased dental wear, reduced dental health, and longevity in captive mammals, when compared with data from wild mammals of the same species. In contrast to the studies noted earlier [Clauss et al, 2007;Kaiser et al, 2009], in which the authors suggest that among some captive mammals, longevity may be reduced, in part owing to reduced dental health; we illustrate that among our captive sample of ring-tailed lemurs, lifespan is at least a decade longer or more than their wild counterparts and corresponds to significantly less tooth wear and/or antemortem tooth loss.…”

“…Given the extreme seasonality in rainfall and resource availability among ringtailed lemurs in southern Madagascar [e.g., Gould et al, 1999Gould et al, , 2003Sauther, 1998;Sauther et al, 1999], the opportunity for captive lemurs to obtain constant food without the need to exploit foods with challenging physical, mechanical, and/or chemical properties, such as at BMSR, is a clear benefit in terms of longevity, limited tooth loss, and low frequency of severe wear. Jurado et al [2008], citing Wenker et al [1998], suggest that good dental health in captive animals is an indicator of adequate health care within a specific zoological context. This may be the case at the Indianapolis Zoo, given the long-term care and support of this zoo's lemur population, but also likely reflects the differences that ring-tailed lemurs encounter in captivity vs. the wild.…”