PSXIV-18 Feeding behavior of feedlot steers fed combinations of feed additives

• Published in: Journal of animal science 2019-12, Vol.97 (Supplement_3), p.437-437
• Main Authors: Dias, Evandro, Sarturi, Jhones O, opheim, Tosha, Henry, Darren D, Hoffmann, Carly A, Sandes, Michael D, Millen, Danilo D, Bouyi, Legrand, miller, markus, Echeverry, Alejandro, Brashears, Mindy, Urso, Phil, Espinoza-Rock, Nadira J
• Format: Article
• Language: English
• Subjects: POSTER PRESENTATIONS
• ISSN: 0021-8812; 1525-3163
• DOI: 10.1093/jas/skz258.865

Abstract The effects of dietary feed additives (single or combination) on feeding behavior of feedlot cattle, and the representativeness of one individual animal within the experimental unit were evaluated. Crossbred-Angus beef steers (n = 240; initial BW = 319 ± 29 kg) were used in an randomized complete block design (block = BW), 4 steers/pen (experimental unit; n = 12/treatment), and randomly assigned to the following treatments: 1) no feed additive; 2) monensin (300 mg/animal-daily) + tylosin (90 mg/animal-daily); 3) monensin + L. salivarius L28 (106 CFU/animal-daily); 4) tylosin; and 5) L. salivarius. Animals were fed (steam-flaked corn-based finishing diet) once-daily (clean-bunk management). Feeding behavior (24 h; 5 min intervals) was measured as time spent in activities. In addition, one steer/pen was individually assessed. The Glimmix procedures of SAS were used for statistical analyses (fixed effect = treatment; random effect = block). Feed additives did not affect time spent eating (163 min/d; P = 0.42); ruminating (71 min/d; P = 0.82); chewing (234 min/d; P = 0.21); drinking (18 min/d; P = 0.59); ruminating/kg of DM (9 min/d; P = 0.75); chewing/kg of DM (30 min/d; P = 0.40); resting (1085 min/d; P = 0.25); or other activities (102 min/d; P = 0.32). The difference between feeding behavior pen average and the value from the single animal marked within the same pen was different from zero for rumination (P ≤ 0.04), eating (P = 0.03), and other activities (P = 0.04), while not different from zero for chewing (P ≥ 0.21), drinking (P ≥ 0.13; except for one treatment P < 0.01), and resting (P ≥ 0.12; tendency exhibited by one treatment P < 0.09). Feed additives seem to not affect feeding behavior half-way-through the finishing phase. One animal within a 4-animal/pen unit did not represent the pen average feeding behavior.