Nutritional and Behavioral Contributions to Dental Disease in Captive Red Kangaroos
Captive macropods often suffer from dental disease frequently requiring tooth extractions. Evidence of bone resorption surrounding affected teeth has been found in some recent clinical cases at the Cleveland Metroparks Zoo. Plausibly, this bone resorption is secondary to inflammation and infection surrounding the affected tooth. However, an alternative hypothesis is that the resorption is evidence of a systemic problem relating to an overall calcium-phosphorus imbalance. In animals with similar digestive processes to those of kangaroos, phosphorus levels are regulated in part by saliva production, which increases with more time spent foraging and chewing. This study addresses the oral health of red kangaroos, Macropus rufus, at the Cleveland Metroparks Zoo. This study determined the effect of providing hay to the animals on exhibit during the day. No change was made to the standard feeding routine of offering hay and formulated diet (pellets) when animals were brought off-exhibit in the evening. Behavioral data was collected on each of the kangaroos with a focus on time spent chewing and/or foraging. Hay was offered on exhibit every other week and weeks without hay provided baseline data. Oral health and disease progression were evaluated through blood analyses (serum calcium phosphorus and osteocalcin), CT scans of jaws, and dental radiographs. Blood work, CT scans, and radiographs were taken before and 6 months after the addition of timothy hay on exhibit. The goal of this study was to evaluate the effect of increased time spent feeding on bone resorption, serum calcium-to-phosphorus ratios, and dental disease in captive red kangaroos.