Individual and Additive Value of Conventional and Non-conventional Technologies in Beef Heifers Housed and Fed Using a GrowSafe® Feeding System
A. R. Harding1, G. K. Jim2, C. W. Booker2, E. J. Behlke2, S. L. Parr2, S. J. Hannon2, T. M. Greer2, Z. D. Paddock2, M. L. May2, L. O. Burciaga-Robles2, and C. R. Krehbiel1; Oklahoma State University1, Feedlot Health Management Services, Ltd., Okotoks, Ab, Canada2
This study evaluated the effects of conventional and non-conventional production (NCP) technologies in feedlot cattle. A total of 384 yearling heifers (859 ± 77 lb.) were stratified by BW and randomly allocated to 1 of 8 treatments: NCP1: fibrolytic feed enzyme (Econase® RDE; Sage Biosciences Inc., Edmonton, Alberta); NCP2: Oleobiotec® Ruminant (Oleo; Laboratoires Phodé, Terssac, France); NCP3: CitriStim® (ADM Alliance Nutrition Inc., Quincy, Illinois); NCP4: Oleo and CitriStim. All NCP systems received a non-medicated supplement. Blended production systems (BP) included: BP1: non-medicated supplement, Oleo, melengesterol acetate (MGA; Zoetis Canada, Kirkland, Québec), and Zilpaterol hydrochloride (Zilmax™; Merck Animal Health, Intervet Canada Corp., Kirkland, Québec) for the last 20 d; BP2: medicated supplement containing Rumensin® and Tylan® (Elanco Animal Health, Guelph, Ontario), MGA, Oleo, and Zilmax for the last 20 d . Control groups included a negative control (NEG): non-medicated supplement; and conventional production (CP): medicated supplement containing Rumensin, Tylan, and MGA, and Zilmax for the last 20 d. Individuals were randomized within diet treatment to receive an implant (Revalor®-200; Merck Animal Health), parasite control (Dectomax® Pour-On Solution; Zoetis Canada), both, or neither. Heifers were fed for 123 days and DMI was recorded using GrowSafe® feeding systems (GrowSafe Systems Ltd., Airdrie, Alberta). Data were analyzed using the GLIMMIX procedure (SAS Institute Inc, Cary, North Carolina). Relative to the NEG group, BP2 and CP treatments had greater live and carcass adjusted ADG and improved live G:F (P < 0.05) and the BP1, BP2, and CP treatments had improved carcass adjusted G:F (P < 0.001). No differences (P > 0.05) were detected in carcass characteristics of NCP and BP groups compared to the NEG and CP groups. Implanted cattle had greater ADG and improved G:F vs. non-implanted cattle (P < 0.001) while no differences (P > 0.05) in feedlot performance or carcass characteristics were detected for parasiticide treatment. No interactions (P > 0.05) were identified between diet, implant status and/or parasiticide. These results indicate that conventional production systems improve beef heifer performance.
Keywords: feedlot, cattle, technology