Scholarly
    Communications Project


Document Type:Dissertation
Name:Rhonda Michelle Hoffman
Email address:rhhoffma@vt.edu
URN:1997/00013
Title:Carbohydrate and Fat Supplementation in Grazing Mares and Foals
Degree:Doctor of Philosophy
Department:Animal and Poultry Sciences
Committee Chair: David S. Kronfeld
Chair's email:kronfeld@vt.edu
Committee\ Members:
Keywords:growth, bone development, milk composition, glucose tolerance, season
Date of defense:June 30, 1997
Availability:Release the entire work for Virginia Tech access only.
After one year release worldwide only with written permission of the student and the advisory committee chair.

Abstract:

The objective of these studies was to design an optimal nutritional supplement suitable for grazing horses using fat and fiber to replace the grain and molasses in the traditional sweet feed. Thoroughbred mares and foals grazing bluegrass/clover pastures were used in these studies, twenty mares and their foals in 1994 to 1995, and twenty mares and foals in 1995 to 1996. Seasonal variation in pasture was examined, and the need for supplementation of nutrients and fibers was assessed. The nutritional status of grazing mares, foals, weanlings and yearlings, fed either a starch and sugar supplement (SS) or a fat and fiber supplement (FF), was examined using growth measurements, radiographic bone evaluations, milk composition and glucose tolerance tests. These studies suggest that fiber may be an important component of an ideal supplement for improved grass/legume pastures. Seasonal variation in pasture indicated an increase in hydrolyzable and rapidly fermed carbohydrates during periods of rapid growth. The FF supplement may have buffered seasonal changes and the increased hydrolyzable carbohydrate content in rapidly growing pasture, as evidenced by smoother growth curves in the yearlings. Young horses, after weaning until the following May, had lower estimated bone mineral content when fed the FF supplement. The lower bone mineral content in the FF supplemented horses may have been due to decreased absorption of calcium or metabolic and hormonal changes associated with adaptation to the different energy sources in the supplements. Milk composition of FF supplemented mares was influenced in ways likely to improve foal health. The FF supplemented mares had enhanced linoleic acid content, which may reduce the risk of gastric ulcers in foals, and increased immunoglobulin G concentration, which may enhance passive immunity. The carbohydrate status of mares, as assessed by glucose tolerance tests, indicated a slower glucose clearance that could be a metabolic adaptation of the mares to the SS and FF supplements.

List of Attached Files

ABSTRACT.PDF ACK.PDF BONE.PDF
CONTENTS.PDF DISCUSS.PDF FIG11.PDF
FIG12.PDF FIG13.PDF FIG14.PDF
FIG21.PDF FIG31.PDF FIG32.PDF
FIG33.PDF FIG34.PDF FIG35.PDF
FIG36.PDF FIG41.PDF FIG42.PDF
FIG43.PDF FIG44.PDF FIG45.PDF
FIG46.PDF FIG51.PDF FIG52.PDF
FIG53.PDF FIG54.PDF FIG55.PDF
FIG56.PDF FIG57.PDF FIG58.PDF
FIG61.PDF FIG62.PDF FIG63.PDF
FIG71.PDF FIG72.PDF FIG73.PDF
FIG74.PDF FIG81.PDF FIG82.PDF
FIG83.PDF FIG84.PDF FIG85.PDF
FIGURES.PDF GLUCOSE.PDF GROWTH1.PDF
GROWTH2.PDF IMPS.PDF INTRO.PDF
LITCITED.PDF MANDM.PDF MILK.PDF
NSC.PDF OS.PDF TABLES.PDF
TITLETD.PDF VITA.PDF hFIG16.PDF
hREVIEW.PDF

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