Defecation rates of white-tailed deer (Odocoileus virginianus) based on fiber content in feces

Objective: To develop three models to estimate the defecation rate of white-tailed deer (Odocoileus virginianus) according to the season of the year, content of neutral detergent fiber (NDF), and acid detergent fiber (ADF) in their feces.Design/methodology/approach: Nine captive adult deer were assigned to three levels of dietary fiber. Fecal groups (defecation rate) were counted, forage consumption estimated, and feces were analyzed for their NDF and ADF content. A randomized block design was used, where the effect of the treatments was blocked by season, and a multiple regression analysis was used to define prediction models of the defecation rates.Results: The defecation rates were different for dietary fiber levels (P0.0001), and for the year season (P0.0007). For spring, the defecation rate model (DR) was DR4.84696[0.02159 (NDF)][0.58397 (ADF)]; for summer DR51.0272[0.26868 (NDF)][1.61121 (ADF)]; and for winter DR7.82939[0.02667 (NDF)][0.17309 (ADF)].Limitations/implications: Defecation rate or fecal group counting is a useful tool to estimate deer populations. Nevertheless, the definition of an adequate defecation rate represents a hard task, since it depends on multiple factors such as environmental conditions and the components of the deer’s diet.Findings/conclusions: The defecation rate varies depending on the year season and the fiber content in the diet.