This Is AuburnElectronic Theses and Dissertations

Post-weaning, Feedyard, and Carcass Performance of Alabama Feeder Cattle: The Current State of Alabama Cattle and the Effect of Backgrounding Diet

Date

2022-06-01

Author

Tigue, Daniel

Type of Degree

PhD Dissertation

Department

Animal Sciences

Abstract

Understanding the effect of post-weaning management strategies on feedyard performance, health, and carcass characteristics of Southeastern beef calves can help cattle producers add value to their operations. However, due to the segmentation of the beef industry in the U.S., feedback from processing facilities and feedyards is rarely received by cow-calf producers that make many management decisions that impact the performance of cattle during those later stages. In an attempt to help producers receive that feedback in the form of performance, health, and carcass data, the Alabama Cooperative Extension System operates the Alabama Pasture to Rail Program (P2R). P2R is a retained ownership program in which cattlemen across Alabama can feed small groups of cattle in a southern plains feedyard and receive all data back on each of their animals, allowing them to make changes to their management programs to improve cattle health and performance. In total, 2,188 calves from 73 farms were consigned and shipped from October 2016 through March 2020. Performance data, carcass characteristics, and profitability metrics were compared by year, by sex, and by health outcome using the PROC GLIMMIX feature of SAS 9.4 (SAS Institute, Cary, NC). Additionally, a stepwise regression was conducted to determine which factors had the greatest impact on profitability. This was conducted using PROC REG feature of SAS 9.4 (SAS Institute, Cary, NC). Additionally, Pearson Correlation Coefficients were used to confirm relationships seen this stepwise regression. Differences in carcass characteristics, growth performance, and profitability were observed (P < 0.05) by year and sex. To understand the effect of backgrounding diet on transportation stress, feedyard adaptation, feedyard performance, and carcass merit, two studies were conducted over the course of two years. Steers and heifers from the E.V. Smith Research Center (Shorter, AL) were subjected to a 60 d backgrounding trial. In year 1, calves were assigned to one of four dietary treatments: cool-season baleage with supplemental dried distiller’s grains with solubles (DDGS), bermudagrass hay with supplemental DDGS, grazing crabgrass/signalgrass pastures with supplemental DDGS, and grazing crabgrass/signalgrass pastures with no supplemental feed. In year 2, calves were assigned to one of four dietary treatments: cool-season baleage with supplemental DDGS, cool-season baleage with supplemental commercial commodity feed, cool-season baleage with no supplemental feed, and bermudagrass hay with supplemental DDGS. In both years, differences between supplemented groups were minimal during the backgrounding period and in the feedyard. Groups that did not receive supplemental feed had reduced performance during backgrounding, but differences between supplemented groups and non-supplemented groups during the feedyard period and at harvest were minimal.