F. M. K. Abouelezz - Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, University of Yucatan (UADY), Mérida, Yucatán, Mexico.
L. Sarmiento-Franco - Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, University of Yucatan (UADY), Mérida, Yucatán, Mexico.
R. Santos-Ricalde - Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, University of Yucatan (UADY), Mérida, Yucatán, Mexico.
J. Segura-Correa - Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, University of Yucatan (UADY), Mérida, Yucatán, Mexico.

The aim of this study was to investigate the range utilization of Rhode Island Red hens, grazing outdoor (under tropical conditions) and to scan their activities inside the house as well as during their outdoor visits. The activities of RIR hens, raised in indoor floor pens connected with outdoor areas covered with natural vegetation, were scanned and recorded individually within ۱۵ minute intervals between ۰۸:۰۰ and ۱۷:۰۰ hours (۳۷ scans a day) for a duration of twelve weeks. The results revealed that, ۴۰.۵% of the hens were observed to be on the range at each scanning time; where they engaged their outdoor visits in foraging (۱۱.۴%), exploring (۸.۶۲%), roaming (۶.۱%), standing (۳.۵%), primping (۵.۶%) and resting (۵.۴%). Besides, the utilization of the closest part of the range to the house was significantly the highest in comparison with the middle and farthest parts (۷۳.۰ vs. ۲۴.۹ and ۲.۱%, respectively), and the highest (P< ۰.۰۵) average utilization of the range was recorded during the early day hours, versus the midday and late day hours. In total, ۲۴ meters apart from the house forms the most adequate distance for free range RIR hens while longer distances would rarely be visited. The grazing RIR hens (in the tropics) utilized the outdoor area effectively and performed natural behavior.

Behavior, Free range, Range utilization, Rhode Island Red, Tropical forage