Session: Ruminant Nutrition III: Feedlot Nutrition

309 - Nutrient Digestibility of Beef Steers Consuming Finishing Diets with an Added Nutritional Packet

Friday, July 16, 2021

9:00 AM – 9:15 AM EST

Location: Kentucky International Convention Center (KICC), L005/009

Presenting Author(s)

Kaue Tonelli Nardi

Masters Student
Texas Tech University
Lubbock, Texas

PDF Slides and Audio

Author(s)

JO

Jhones Onorino Sarturi, n/a

Associate Professor
Texas Tech University
Lubbock, Texas
DH

Darren D. Henry, n/a

Assistant Professor
Texas Tech University
Lubbock, Texas
FC

Francine M. Ciriaco, n/a

Post Research Associate
Texas Tech University
Lubbock, Texas
NH

Nelson O. Huerta-Leidenz

Research Associate
Texas Tech University
Lubbock, Texas
Andrea M. Osorio Doblado, MA

Research Assistant
Texas Tech University
Lubbock, Texas
IG

Igor Gomes Fávero

Student Intern
Texas Tech University
Lubbock, Texas
Kaliu G. Scaranto Silva

Student Intern
Texas Tech University
IDALOU, Texas
CR

Camron J. Rush

Undergraduate Student
Texas Tech University
Lubbock, Texas

The effects of a nutritional packet fed to beef steers during the final 64 d of the feedlot finishing phase on apparent total tract nutrient digestibility were evaluated. Angus-crossbred steers (n =120; initial BW = 544 ± 52 kg) were assigned to 30 pens (4 steers/pen; 15 pens/treatment; pen = experimental unit) in a randomized complete block design. A steam-flaked corn-based finishing diet was fed ad libitum and treatments applied as follows: 1) control and 2) 30 g/steer-daily (DM-basis) of the nutritional packet [containing live yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g), vitamin C (5.4 g/kg), vitamin B1 (13.33 g/kg), NaCl (80 g/kg) and KCl (80 g/kg)]. The nutritional packet used ground corn as a carrier and was included at 1% of diet DM. Orts were quantified daily (if any) and subtracted from the total dietary DM offered to calculate DM intake. Fecal samples were collected twice daily (0700 and 1700 h) for 5 consecutive days (d 47 to 51) from at least 3 steers within pen. Feed samples were collected daily at time of feeding (0630 h). Fecal and feed samples were composited to represent the collection period, dried (55^oC), ground (1 mm), and analyzed to assess DM, OM, NDF, ADF, and hemicellulose. In situ (288 h) iNDF was used as an internal marker to measure apparent total tract nutrient digestibility. Data were analyzed using the GLIMMIX procedure of SAS. Intake of DM, OM, and fiber components during the digestibility period was not affected (P ≥ 0.44) by treatment. Steers fed the nutritional packet had increased apparent total tract digestibility of OM (P = 0.02), DM (P = 0.01), NDF (P = 0.02), ADF (P = 0.01), and hemicellulose (P = 0.08; tendency). Improved nutrient digestibility without affecting nutrient intake may warrant an enhanced energy deposition in the carcass.