Characterization and tenderness prediction of a population of two types of predominately brahman, two types of predominately angus, and 1/2 brahman X 1/2 angus /

This research had two primary objectives: to characterize a

Bibliographic Details
Main Author: Morgan, Wayne Wallace, 1966-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1997.
Subjects:
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Description
Summary:This research had two primary objectives: to characterize a
population of Angus and Brahman cross calves and to predict
tenderness as determined by Warner-Bratzler shear force
(SHEAR) and trained sensory panel overall tenderness ratings
(OTEND) with carcass and histological traits for this
population of calves. The population consisted of steers and
heifers (n = 475) from 33 different families that were
processed over a 4 yr period. All calves were the product of
embryo transfer to generate multiple siblings within each
family. Data were analyzed for Family within Breed Type,
Breed Type (Angus sire X 1/2 Angus 1/2 Brahman dam; 1/2 Angus
1/2 Brahman sire X Angus dam; Brahman sire X 1/2 Angus 1/2
Brahman dam; 1/2 Angus 1/2 Brahman sire X Brahman dam; 1/2
Angus 1/2 Brahman X 1/2 Angus 1/2 Brahman), Sex, and Kill
Group (season and year) effects. Family within Breed Type
had a significant effect on most traits analyzed. The
variation present between Families within each Breed Type
suggests selection should be based on individual genetic
lines, not on breeds. Some traits noted a Breed Type effect,
but notably absent from that list is marbling score, USDA
quality grade, SHEAR and trained sensory panel ratings for
muscle fiber tenderness and OTEND. Steers had heavier HCWT,
less KPH, less adjusted fat thickness (ADJFAT), and lower YG
than heifers. Prediction models for SHEAR and OTEND with
carcass and histological traits yielded adjusted R[] of .1854
and .2794, respectively. For prediction of SHEAR, variables
FAT, LMA, SARC, and FRAG were used in the model. For
prediction of OTEND, variables SARC, LMA, FAT, lean maturity
(LEAN), and FRAG were used in the model. With the exception
of LMA, these traits all have been shown to be related to
tenderness. Prediction of SHEAR and OTEND for the
predominately Angus and predominately Brahman calves
separately yielded different models. However, simple
correlations between SHEAR and OTEND did not differ between
predominately Brahman and predominately Angus calves.
Item Description:Vita.
"Major Subject: Animal Science".
In title, numerals are used.
Physical Description:xi, 87 leaves ; 28 cm.
Issued also on microfiche from University Microfilms Inc.
Bibliography:Includes bibliographical references: pages 80-86.