Search

Effects of a nutritional packet strategically offered to calf-fed system steers on growth performance, nutrient digestibility, feeding behavior, ruminal variables, and carcass characteristics were evaluated. Angus crossbred steer-calves (N  = 60; body weight [BW] = 234 ± 4 kg) were used in a randomized complete block design (block = BW) and stratified into two treatments: 1) control; and 2) 30 g/steer-daily (dry matter [DM] basis) of a nutritional packet containing (steer-daily basis): Live yeast (Saccharomyces cerevisiae ; 1.7 × 1010 CFU), vitamin C (Ascorbic acid, 162 mg), vitamin B1 (thiamin hydrochloride, 400 mg), sodium chloride (2.4 g), and potassium chloride (2.4 g). Animals were offered (electronic feed-bunks [SmartFeed, C-Lock Inc. Rapid City, SD]), a steam-flaked corn-based finishing diet to ad libitum (individual intake), once daily for 233 d. Treatments were offered during the first and last 60 days on feed (DOF). The GLIMMIX procedure of SAS was used, with steer as the experimental unit, treatment and phase (for feeding behavior and digestibility) as fixed effects, and BW-block as a random effect. Steers offered the nutritional packet had 14% less (P  < 0.01) intake and 18% greater (P  = 0.01) feed efficiency during the initial 30 DOF. Intake (days 0 to 233) was 6% greater (P  = 0.02) for steers offered the nutritional packet, while BW gain was not different (P  ≥ 0.44). Greater (P  = 0.02) dressing percent (61.1% vs. 62%) for steers offered the packet was observed, while other carcass variables were not different (P  ≥ 0.33). Digestibility of DM, organic matter, and fiber were greater (P  < 0.01) for steers offered the packet. Steers offered the packet spent 13% less time eating during the first 60 DOF, while during the last 60 DOF a 14% greater meal frequency and 12.3% smaller mean meal size (treatment × phase interaction, P  < 0.02) were observed. Steers offered the packet had a reduced (P  ≤ 0.01) mean meal duration during both phases. Regardless of treatment, a decreased rumination (P  ≤ 0.03) and chewing (P  ≤ 0.01) activities were observed for the last 60 DOF compared to the first 60 DOF. Ruminal papillae area was 30% greater (P  = 0.02) and the total volatile fatty acid (VFA) tended (P  = 0.09) to be greater for steers offered the nutritional packet. The nutritional packet offered to calf-fed steers improved feed efficiency during the initial 30 d after arrival, while inducing superior overall intake, nutrient digestibility, dressing percentage, ruminal papillae area, and total ruminal VFA. [ABSTRACT FROM AUTHOR]

The effects of a nutritional packet containing a direct-fed microbial combined with vitamins/electrolytes offered at the beginning and end of the finishing phase to beef steers in a calf-fed system on feeding behavior were evaluated. Angus crossbred steer-calves (n = 18; BW = 234 ± 4 kg) were assigned to a randomized complete block design (block = body weight; steer = experimental unit) and stratified into two treatments: a) control (no packet, finely-ground corn carrier only); and b) 30 g of DM/animal-daily of a nutritional packet [live-yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g), vitamin C (5.4 g/kg of ascorbic acid), vitamin B1 (13.33 g/kg of thiamine hydrochloride), and electrolytes of NaCl (80 g/kg) and KCl (80 g/kg)]. Animals were individually offered [electronic feed-bunks (Smart-Feed/C-Lock Inc.)] a steam-flaked corn-based finishing diet ad libitum once daily for 233 d, while treatments were offered during the first (phase-1) and last 60 d (phase-2) on feed only. Feeding behavior activities were assessed in min/d by using CowManagerTM ear tag sensors. Data were analyzed using the GLIMMIX procedure of SAS. There was no treatment × phase interactions (P ≥ 0.15), except that steers receiving the nutritional packet tended (P = 0.10) to spend more time (6 vs. 9 min/kg) eating digestible DM during phase-2 only. Regardless of phase, steers consuming the nutritional packet spent more time (P = 0.04) eating per kg of hemicellulose. Regardless of treatment, a decreased rumination (P ≤ 0.03) and chewing (P ≤ 0.01) activity-variables were observed for the phase-2 compared to phase-1. Steers receiving the nutritional packet exhibited superior time spent on eating activities, especially during the final 60 d before slaughter, and fiber seems to be the major driver inducing such effect. Towards the end of the finishing phase, cattle reduced rumination and chewing compared to the arrival phase. [ABSTRACT FROM AUTHOR]

The effects of a nutritional packet containing a direct-fed microbial combined with vitamins/electrolytes offered to beef steers in a calf-fed system on ruminal papillae morphology and volatile fatty acid (VFA) profile were evaluated. Angus crossbred steercalves (n = 60; BW = 234 ± 4 kg) were assigned to a randomized complete block design (block = body weight; steer = experimental unit) and stratified into two treatments: a) control (no packet, finely-ground corn carrier only); and b) 30 g of DM/animal-daily of a nutritional packet [live-yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g), Vitamin C (5.4 g/kg of Ascorbic acid), Vitamin B1 (13.33 g/kg of Thiamine hydrochloride), and electrolytes of NaCl (80 g/kg) and KCl (80 g/kg)]. Animals were individually offered [electronic feed-bunks (Smart-Feed/C-Lock Inc.)] a steamflaked corn-based finishing diet ad libitum once daily for 233 d, while treatments were offered during the first and last 60 days on feed only. Upon harvest (federally inspected facility), individual samples of ruminal cranial sac epithelium and rumen content (quickly frozen) were collected. Preserved (70% alcohol at 5oC) ruminal tissue fragments were trimmed (1 cm2), in which papillae were counted, followed by a random removal of 12 individual papillae for further area measurement using electronic scanning (ImageJ). Data were analyzed using the GLIMMIX procedure of SAS. Steers offered to nutritional packet had a 30% increased (P = 0.02) average papillae area, which induced a tendency (P = 0.14) to improve ruminal absorptive surface area (89 vs. 93%), while not affecting ruminal papillae number (P = 0.39). Molar proportions of acetate, butyrate, and propionate were not affected (P ≥ 0.51) by treatments, while total VFA (mM) tended (P = 0.09) to increase by 8% for animals consuming the nutritional packet. The nutritional packet seemed to improve ruminal fermentation products while positively affecting ruminal papillae morphology. [ABSTRACT FROM AUTHOR]

The effects of a nutritional packet containing a direct-fed microbial combined with vitamins/electrolytes offered to beef steers in a calf-fed system on growth performance and carcass characteristics were evaluated. Angus crossbred steer-calves (n = 60; BW = 234 ± 4 kg) were assigned to a randomized complete block design (block = body weight; steer = experimental unit) and stratified into two treatments: a) control (no packet, finely-ground corn carrier only); and b) 30 g of DM/animal-daily of a nutritional packet [live-yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g), Vitamin C (5.4 g/kg of Ascorbic acid), Vitamin B1 (13.33 g/kg of Thiamine hydrochloride), and electrolytes of sodium chloride (80 g/kg) and potassium chloride (80 g/kg)]. Animals were individually offered [electronic feed-bunks (Smart-Feed/C-Lock Inc.)] a steam-flaked corn-based finishing diet ad libitum, once daily for 233 d. Treatments were offered during the first (phase-1) and last (phase-2) 60 d on feed. Body weight measurements were taken every 30 d before feeding. Data were analyzed using the GLIMMIX procedure of SAS. Steers offered the nutritional packet had 14% less (P < 0.01) intake and 18% greater gain efficiency during the initial 30-d on feed, while such advantage did not (P = 0.26) persist when accounting for the initial 60 d for either variable. Overall intake (d0 to d233) was 6% greater (P = 0.02), while carcass-adjusted ADG (1.61 vs. 1.56), and carcass-adjusted gain efficiency (0.198 vs. 0.204) were unaffected (P = 0.44) compared with control, respectively. Dressing percent of steers offered the packet was 1 percentage-unit greater (P = 0.02), while other carcass variables were unaffected (P = 0.33). Calffed steers seem to benefit from such nutritional packet during the initial 30 d after feedlot arrival, while both superior intake and dressing percentage appears to last until cattle harvest. [ABSTRACT FROM AUTHOR]