We investigated the influence of two types of winter supplementation on activity patterns of heifers on northern Great Plains rangeland. The experiment was conducted at the USDA-ARS Fort Keogh LARRL in Miles City, MT during 18 days in January 2015. One group of 68 heifers was fed 1.82 kg of a 20% crude protein cake supplement/day/heifer (CAKE) delivered daily at approximately 10:00 AM, while another group of 66 heifers was provided a self-fed high protein plus mineral supplement designed to be consumed at 0.11 to 0.45 kg/heifer/day (SELF). Lotek 3300 GPS collars were fitted on five heifers per treatment to monitor movement at 5 min. intervals. The influence of supplementation treatment on daytime (7:00AM - 7:00 PM) activity patterns was explored by classifying points on the basis of movement velocity (m/min). Chi square tests were used to analyze the influence of treatment on daytime frequency of resting (< 1 m/min), traveling (>=20 m/min) and grazing (between 1-20m/min) events. Daytime activity patterns were significantly associated with supplementation treatment (Chi sq. 121.13, P<0.01). Lower daytime grazing events were recorded for CAKE vs. SELF heifers (62.1 vs.73.0%). CAKE heifers exhibited higher frequency of resting (29.1%) and travel (8.8%) events compared to their SELF counterparts (23% and 4%, respectively). A self-fed supplement such as that used in this study might provide a better means of feeding supplemental protein to stimulate use of dormant forage resources on rangeland.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.