Document Type

Thesis - Open Access

Award Date

2019

Degree Name

Master of Science (MS)

Department

Animal Science

First Advisor

Julie A. Walker

Second Advisor

Cody Wright

Abstract

The objectives of the present study are to evaluate feeding behavior, animal performance and carcass characteristics of beef growing steers fed increasing amounts of carinata meal (CM). Due to the high protein content of the CM after the oil extraction for biofuel there is an opportunity to use it as a protein supplementation in beef cattle. Twenty-four steers blocked by weight were assigned to four corn-based diets (n = 6 animals per treatment). In the three treatment diets, carinata meal replaced high-moisture corn at 5, 10, or 15%. The diets were fed using the Insentec RIC system for 138 days. During the feeding period, individual feed disappearance, feeding behaviors, and growth performance were recorded. At the conclusion of the feeding period, the steers were harvested at a commercial abattoir where carcass characteristics were measured. Data were analyzed as randomized complete block with diet as the fixed effect and block as the random effect using the PROC MIXED procedure of SAS. Linear and quadratic contrast were used to evaluate the effect of incremental levels of CM in the diets. Steer was the experimental unit for all analyses and α-value of 0.05 was used to declare significance. Trends were identified when 0.05 ≤ P ≤ 0.10. A quadratic effect (P < 0.01) was observed in DMI where DMI increased with incremental levels of CM up to 10% in the diets then decreased. Carinata meal had a quadratic effect on body weight on d 84 and 138 (P = 0.05 and 0.003, respectively). Body weights were lower in calves fed the control diet (CONT) and those fed the highest level of carinata meal (CM15). Carinata meal inclusion had a quadratic effect (P = 0.008) on overall average daily gain (ADG) in the finishing period. Calves fed lower levels of CM meal gained faster than those fed either 0 or 15%. Gain:feed was not affected by treatment (P = 0.11). There was a quadratic (P = 0.002) effect of CM inclusion on hot carcass weight (HCW). Weights increased from CONT to 5% CM meal (CM5) treatment, was consistent to 10% CM inclusion (CM10), and then decreased when CM was fed at 15% of the diet (CM15). There were no effects (P > 0.05) of treatment on REA or MARB. There was a quadratic effect (P = 0.005) of CM inclusion on backfat (BF) in which BF increased from CONT to CM10, then decreased with incremental levels of CM. There was a quadratic change observed on % KPH (P = 0.02) and YG (P = 0.009). These variables increased from CONT to CM10, then decreased with CM15 in the diets. Dry matter meal size (DMMS) tended to increase from CONT to CM5 and CM10 and decreased at CM15 (Quadratic, P = 0.09). Inter meal interval (IMI) increased linearly (P < 0.01) with incremental levels of CM in the diet. A linear decrease (P < 0.001) in meal duration (MD) was observed as the level of CM increased in the diet. A quadratic effect of treatment on as-fed meal size (MS; P = 0.04) was observed with increasing levels of CM in the diet. As-fed meal size increased from CONT to CM5, then decreased as the level of CM inclusion increased in the diet. This research suggests that CM may be able to serve as a functional source of crude protein in beef cattle finishing diets, but there may be an upper inclusion limit without reducing performance. Further research needs to be completed to determine the value of CM as a protein supplement.

Format

application/pdf

Number of Pages

69

Publisher

South Dakota State University

Rights

In Copyright - Educational Use Permitted
http://rightsstatements.org/vocab/InC-EDU/1.0/

Included in

Beef Science Commons

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