284 Influence of three times weekly alfalfa supplementation on the behavior of beef cows grazing dormant Montana rangeland

Abstract

Abstract The objectives of this research were to determine how daily and hourly distance traveled, grazing time, and resting time of beef cows are influenced relative to the timing of supplementation. Over two winters, a herd of commercial Angus cows grazed in a 645-ha Montana foothill rangeland pasture for 56 days between December and February each year. At 1300 every Monday, Wednesday and Friday, all cows were gathered and taken to a central location in the pasture where 3.18 kg∙hd-1 of alfalfa pellets (17% CP) were immediately delivered. Each year, 18 cows were randomly assigned a global positioning system (GPS) collar. Using the GPS collar data, distance traveled, grazing time, and resting time were estimated for each hour and day for each cow. Activity was grouped into the 24-h period pre-supplementation and 24-h period post-supplementation. Cows traveled 1.7 km further and grazed for 0.7 h less per day post-supplementation (P < 0.01). Daily resting time was similar pre- and post-supplementation (P = 0.07). Post-supplementation, cows traveled further in the afternoon and morning and reduced grazing in the afternoon and at night (P < 0.05). Cows rested less in the morning pre-supplementation and in the afternoon post-supplementation (P < 0.03). Results indicate that three times weekly supplementation alters cow activity, though differences are mostly associated with the time surrounding when supplement is delivered.