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Performance Comparisons of Finishing Systems for Yearling Heifers

Wednesday, March 19, 2014
Grand Ballroom - Posters (Community Choice Credit Union Convention Center)
Jared M. Mracek , University of Nebraska, Lincoln, NE
Jason M. Warner , University of Nebraska, Lincoln, NE
Bradley R. Wetovick , University of Nebraska, Lincoln, NE
Dennis E. Bauer , University of Nebraska, Ainsworth, NE
Twig T. Marston , University of Nebraska, Norfolk, NE
Jim C. MacDonald , University of Nebraska-Lincoln, Lincoln, NE
Richard J. Rasby , University of Nebraska, Lincoln, NE
Abstract Text:

A 2-yr study compared performance and carcass characteristics between traditional and alternative yearling finishing systems. Heifers were weighed and randomly assigned to one of two groups: Control or Self-fed. Data were analyzed as a completely randomized design with treatment as a fixed effect, year as a random variable, and pasture being the experimental unit. Heifers grazed upland sandhills range for 129 d followed by feedlot finishing for 103 d (CON, n = 24/yr). In the alternative system, heifers grazed upland sandhills range for 138 d with ad libitum access to a self-fed dried distillers grains based supplement (SF, n = 24/yr). The SF heifers had a one-third greater stocking rate compared to CON, because the supplement (4.63 kg DM/heifer/d) replaced grazed forage. Residual forage was similar (P = 0.66) between treatments. Heifers were harvested when twelfth rib backfat was visually estimated to be 1.27 cm, but backfat at harvest was different so data were adjusted to a 28% empty body fat. The SF heifers had greater ADG (P < 0.01) and ending BW (P < 0.01) on pasture, but CON heifers had greater HCW (P < 0.01) and greater final BW (P < 0.01). There was greater G:F ratio on grass( P < 0.01) and during the feedlot phase (P = 0.04) for SF heifers. Marbling score and LM area were greater (P < 0.01) for CON heifers. However, SF heifers reached market weight in 94 fewer d than CON heifers while having similar performance. This alternative production system may provide a viable option for marketing heifers in a cow/calf or yearling enterprise.

Table 1. Performance and carcass characteristics of control (CON) and self-fed (SF) heifers

 

Adjusted1

 

 

Item

Control

Self-Fed

SEM

P-value

Initial BW, kg

312

307

8.99

0.33

Off Grass BW, kg

412

520

5.91

<0.01

ADG On Grass, kg

0.79

1.54

0.04

<0.01

Days on Grass

129

138

8.14

0.17

Days in Feedlot

103

---

---

---

HCW, kg

357

323

8.42

<0.01

Final BW, kg

567

520

13.59

<0.01

System ADG, kg2

1.14

1.54

0.04

<0.01

Feedlot ADG, kg3

1.59

1.54

0.09

0.46

G:F Grass

0.09

0.16

0.004

<0.01

G:F Feedlot

0.15

0.16

0.008

0.04

% EBF

28

28

---

---

1Data adjusted to 28% empty body fat (Guiroy et al. 2001)

2Using days in system: (CON: May-December; SF: May-October)

3Using days in system: (CON: September-December; SF: May-October)

Keywords: Heifer, Distiller Grains, System