Evaluation of fat sources on cholesterol and lipoproteins using genetically selected pigs as human models /

At approximately 8 weeks of age, four-way cross (Chester

Bibliographic Details
Main Author: Harris, Kerri Beth King, 1964-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1994.
Subjects:
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Description
Summary:At approximately 8 weeks of age, four-way cross (Chester
White x Landrace x Large White x Yorkshire) pigs (n = 24)
were selected based on genetically high (H) or low (L) serum
cholesterol levels - 12 from each genetic group - to
determine the relationship between genetics, fat source and
sex class on serum cholesterol, growth, carcass
characteristics, and the cholesterol and lipid content of
muscle and adipose tissues. Boars and gilts, six each from
the two genetic groups, were assigned randomly to one of
three dietary treatments for 46 days. A standard grower diet
was modified to include either beef tallow (T), corn oil (CR)
or coconut oil (CC), and the pigs were given ad libitum
access to feed. Cholesterol was added to each diet to ensure
that the measured changes were due to fat sources and not
cholesterol differences between the diets. There were no
differences between boars and gilts at the initial evaluation
or at the end of the treatment; therefore, means were pooled
for statistical analyses. No differences were found for live
weights taken on day 1, 18, 29 and 46. The CR diet had a
higher apparent digestibility (P <.01) than the T or CC
diets, but genetic background did not influence apparent
digestibility. Blood samples were taken on day 1, 29, and 46
via the jugular vein. The total serum cholesterol
concentration was different between the two genetic groups at
the start of the study (H = 1296︢, L = 1045︢; P <.Ol). The
ending values (H = 1511︢0, L = 1307︢) were not significantly
different; however, the same trend occurred. Differences (P
< .01) were found between dietary treatments for total
cholesterol on day 29 (T = 1781︢1, CR = 1291︢0, CC = 1518︢),
but by day 46, differences were resolved. Pigs were
slaughtered on day 46, and carcass data were collected.
There were no differences in fat deposition at the first rib,
10th rib, last rib, or last lumbar vertebra, but differences
were found between genetic groups for longissimus muscle area
(H = 21.0.︢8, L = 18.11︢.0; P <.05) and USDA muscle score (H
= 2.1.︢l, L = 1.7.︢l; P <.05). There were no differences in
cholesterol content of the pre-rigor or post-rigor
longissimus muscle for either genetics or diet. Neither
genetics nor dietary treatment affected the cholesterol
content of the adipose tissue. However, the pre-rigor muscle
tissue also had lower values for the cholesterol content than
did the post-rigor tissues. There were no differences in fat
percentage between genetic groups for any of the tissues
analyzed. However, there was a genetic group X sex class
interaction for the post-rigor longissimus fat content.
There were differences in total lipid content among the
dietary treatments for the pre-rigor and post-rigor
longissimus muscle. Overall, genetic background had an
impact on serum cholesterol, and dietary fat intake
influenced lipid content in muscle tissues.
Item Description:Vita.
"Major Subject: Nutrition".
Physical Description:xi, 47 leaves : illustrations ; 28 cm.
Issued also on microfiche from University Microfilms Inc.
Bibliography:Includes bibliographical references.