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Current dogma suggests increased dietary roughage may improve calf health at the expense of performance during receiving. In experiment 1, the effects of increasing dietary roughage on performance and clinical health of high-risk heifers was evaluated over a 56-d receiving period. Heifers (n  = 589; initial body weight; BW  = 230 ± 33 kg) were sourced from Oklahoma livestock auctions from April through October of 2019. Heifers were randomly assigned to pens, which were randomly assigned to 1 of 3 experimental dietary treatments in a randomized complete block design. Diets contained either: 1) 15% roughage (R15), 2) 30% roughage (R30), or 3) 45% roughage (R45) in the form of prairie hay. Orthogonal contrasts were used to test for linear and quadratic responses among experimental treatments. There was a linear decrease in overall average daily gain (ADG ; P  ≤ 0.0001) with increasing roughage inclusion which resulted in a linear decrease (P  ≤ 0.0001) in heifer final BW. A linear increase (P  ≤ 0.01) was observed for overall dry matter intake (DMI), and overall gain:feed (G:F) decreased linearly (P  ≤ 0.0001) as dietary roughage concentration increased. A quadratic response to decreasing roughage was observed (P  = 0.02) for the percent of calves treated three times for bovine respiratory disease (BRD). No other responses (P  ≥ 0.11) were detected in animal health variables. In experiment 2, Angus steers (n  = 12) and heifers (n  = 6; BW = 272 ± 28 kg) were acquired from a single ranch in Oklahoma to evaluate the same experimental dietary treatments on serum metabolite concentrations. Animals were randomly assigned to experimental treatments, with animal serving as the experimental unit in experiment 2. Statistical models for serum metabolites in experiment 2 were analyzed using repeated measures with the effects of treatment, time, and treatment × time. In experiment 2, there were tendencies for treatment × time interactions for blood urea nitrogen (BUN ; P  = 0.07) and nonesterified fatty acid (NEFA ; P  = 0.06) concentrations. No metabolites were affected by treatment (P  ≥ 0.11), while all metabolites were impacted by time (P  ≤ 0.02). In summary, growth performance was improved in calves as dietary roughage concentration decreased with minimal impacts on health and serum metabolites. These results suggest that diets containing as little as 15% roughage can be used during receiving to improve calf performance without compromising calf health when fibrous byproducts are included in the diet. [ABSTRACT FROM AUTHOR]

Automatic feeding systems are being used more frequently to understand individual cattle behavior and intake variation when cattle are group housed. The objective of this experiment was to evaluate if bunk preference exists, and if so, how bunk preference affects performance, intake, or efficiency of feedlot steers. Angus steers (n = 123; initial BW = 293 ± 33.8 kg) were blocked by BW and sire and assigned to 1 of 4 pens, each containing 6 automated feed bunks (Insentec RIC; Hokofarm Group, Marknesse, Netherlands), in a randomized complete block design. Steers were fed a common diet and free to consume feed from any bunk within the pen without restriction. A steer's preferred bunk was defined as the bunk from which the most feed was consumed. In any week, 80% of steers consumed less than 29% of that week's total feed intake from the preferred bunk, indicating no strong preference for a specific bunk. The maximum weekly feed intake consumed from a preferred bunk was 57%. Further, the percentage of intake from the preferred bunk did not affect overall ADG, feed intake, or G:F (P > 0.64). These results suggest that a few steers may have a relatively strong preference for a specific feed bunk; however, this preference was not associated with performance, intake, or efficiency. Researchers can design experiments (at a stocking density of 5 steers per bunk) that restrict or alter an individual animal's access to any specific bunk, because such access, or lack of access, does not alter the animal's performance or feed intake. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effects of supplementation level and type on forage intake of steers grazing a high-quality native range. This study was conducted in late May through the end of June. On d 0, steers (n=16, initial BW = 193.7 kg ± 14.3 kg) were randomly assigned to one of 5 dietary treatments, fed once daily in individual stalls for 28 d. Treatments were control (no supplement, n=4), or supplemented with either cottonseed meal or dry rolled corn, each at either 0.45 kg or 1.81 kg as-fed/d (n=3 for each combination). Beginning on d 7, steers were orally administered titanium dioxide boluses (10 g/steer) once daily for 21 d. Fecal samples were collected from the rectum once daily for 14 d, analyzed for Ti concentration via a handheld X-ray fluorescence analyzer, and total fecal output was estimated. Diet digestibility was estimated after a 288-h in situ incubation of forage and fecal samples to determine indigestible NDF. Some steers had orts, therefore actual mean supplement intake was used in analysis. Results were analyzed with regression, with animal as the experimental unit. Mean estimated forage DMI of unsupplemented animals was 1.6% BW. Contrary to expectation, corn supplemented steers exhibited greater forage DMI as a percentage of BW than cottonseed meal supplemented steers (P = 0.01; 1.5 vs. 1.1, respectively). [ABSTRACT FROM AUTHOR]