The Provision of Browse and Its Impacts on the Health and Welfare of Animals at the Zoo: A Review.

Browsers are animals that consume significant proportions of leaves, twigs, and bark from woody plants. These species have evolved morphological, physiological, and behavioral adaptations to subsist on a specialized diet. In zoos and other managed care facilities, the provision of browse in appropriate amounts helps promote positive animal welfare. Feeding on browse fulfills behavioral needs and reduces stereotypies, promotes satiety, and provides opportunities for dietary choice and control. However, there are several obstacles that can prevent institutions from providing browse, including physical and chemical hazards, palatability issues, and the difficulty in quantifying the nutritional value of browse. In addition, providing large enough quantities of browse can be challenging, and fresh browse may be especially difficult to provide for zoos in temperate climates. We describe the methods currently utilized to preserve browse and discuss their strengths and weaknesses. We recommend areas of future research for browse provision in zoos.