Journal of Animal Science, Vol 79, Issue 9 2327-2335, Copyright © 2001 by American Society of Animal Science

JOURNAL ARTICLE

Shade and water misting effects on behavior, physiology, performance, and carcass traits of heat-stressed feedlot cattle

F. M. Mitlohner, J. L. Morrow, J. W. Dailey, S. C. Wilson, M. L. Galyean, M. F. Miller and J. J. McGlone
Department of Animal Science & Food Technology, Texas Tech University, Lubbock 79409-2141, USA.

One hundred twelve crossbred feedlot heifers were used in two experiments to assess the impact of heat stress and its relief by shade and(or) water misting on behavior, physiology, performance, and carcass traits. Treatments were 1) no shading or misting (CONT); 2) only misting (MIST); 3) only shading (SHADE); and 4) shading plus misting (SHMI). Head in the feed bunk, head in or above the waterer, walking, standing, and lying behaviors were observed. Rectal temperature, respiration rate, and carcass traits were measured, as well as DMI, ADG, and feed:gain. Dietary NEm and NEg concentrations were calculated from performance data. In Exp. 1, (32 heifers; average BW 288 kg) the CONT heifers spent more time lying down than all others (P < 0.01). In addition, CONT heifers spent less time (P < 0.01) standing than SHADE and MIST heifers. Misting decreased (P < 0.01) rectal temperature and MIST as well as SHADE lowered (P < 0.05) respiration rates. In Exp. 2 (80 heifers; average BW = 336 kg), lying and walking behaviors did not differ among treatments, but shade increased (P < 0.01) standing behavior in heifers. The MIST cattle performed less (P < 0.05) head-above-water behavior than unmisted cattle. Rectal temperatures did not differ among treatments, but respiration rate was lower in shaded than in unshaded heifers (P < 0.05). Shaded compared with unshaded heifers had greater DMI (9.46 vs 8.80 +/- 0.14 kg/d, P < 0.01) and ADG (1.6 vs 1.41 +/- 0.1 kg/d, P < 0.01). Heifers provided with shade reached their target BW 20 d earlier than the unshaded heifers and differed in final BW (547 vs 520 +/- 6 kg, P < 0.01). Feed:gain and calculated NEg and NEm concentrations did not differ among treatments, and carcass traits were generally similar among treatments. In conclusion, cattle without shade had a physiological and behavioral stress response to heat that negatively affected productivity. Providing shade for beef cattle was a suitable solution to decrease heat stress and to lower the negative effects of heat on performance, whereas misting was largely ineffective.

This article has been cited by other articles:

				J. B. Gaughan, T. L. Mader, S. M. Holt, and A. Lisle A new heat load index for feedlot cattle J Anim Sci, January 1, 2008; 86(1): 226 - 234. [Abstract] [Full Text] [PDF]

				P. E. Kendall, G. A. Verkerk, J. R. Webster, and C. B. Tucker Sprinklers and Shade Cool Cows and Reduce Insect-Avoidance Behavior in Pasture-Based Dairy Systems J Dairy Sci, August 1, 2007; 90(8): 3671 - 3680. [Abstract] [Full Text] [PDF]

				T. L. Mader, M. S. Davis, and T. Brown-Brandl Environmental factors influencing heat stress in feedlot cattle J Anim Sci, March 1, 2006; 84(3): 712 - 719. [Abstract] [Full Text] [PDF]

				J. L. Morrow, F. M. Mitloehner, A. K. Johnson, M. L. Galyean, J. W. Dailey, T. S. Edrington, R. C. Anderson, K. J. Genovese, T. L. Poole, S. E. Duke, et al. Effect of water sprinkling on incidence of zoonotic pathogens in feedlot cattle J Anim Sci, August 1, 2005; 83(8): 1959 - 1966. [Abstract] [Full Text] [PDF]

				N. R. St-Pierre, B. Cobanov, and G. Schnitkey Economic Losses from Heat Stress by US Livestock Industries J Dairy Sci, July 1, 2003; 86(13_suppl): E52 - 77. [Abstract] [Full Text] [PDF]

				T. L. Mader Environmental stress in confined beef cattle J Anim Sci, February 1, 2003; 81(14_suppl_2): E110 - 119. [Abstract] [Full Text] [PDF]

				F. M. Mitlohner, M. L. Galyean, and J. J. McGlone Shade effects on performance, carcass traits, physiology, and behavior of heat-stressed feedlot heifers J Anim Sci, August 1, 2002; 80(8): 2043 - 2050. [Abstract] [Full Text] [PDF]