Nutritional Adequacy and Performance of Raw Food Diets in Kittens

184 Pages·2016·2.87 MB·English

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Doctoral Dissertations Graduate School
8-2012
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Beth Alair Hamper
[email protected]
Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss
Part of the Dietetics and Clinical Nutrition Commons
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Hamper, Beth Alair, "Nutritional Adequacy and Performance of Raw Food Diets in Kittens. " PhD diss.,
University of Tennessee, 2012.
https://trace.tennessee.edu/utk_graddiss/1389
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To the Graduate Council:
I am submitting herewith a dissertation written by Beth Alair Hamper entitled "Nutritional
Adequacy and Performance of Raw Food Diets in Kittens." I have examined the final electronic
copy of this dissertation for form and content and recommend that it be accepted in partial
fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in
Comparative and Experimental Medicine.
Joseph W. Bartges, Major Professor
We have read this dissertation and recommend its acceptance:
Claudia A. Kirk, Stephen A. Kania, Melissa Kennedy, David A. Bemis, Robert N. Moore
Accepted for the Council:
Carolyn R. Hodges
Vice Provost and Dean of the Graduate School
(Original signatures are on file with official student records.)
To the Graduate Council:

I am submitting herewith a dissertation written by Beth Alair Hamper entitled “Nutritional
Adequacy and Performance of Raw Food Diets in Kittens.” I have examined the final electronic
copy of this dissertation for form and content and recommend that it be accepted in partial
fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in
Comparative and Experimental Medicine.

_____________________________
Joseph W. Bartges, Major Professor

We have read this dissertation
and recommend its acceptance:

_______________________________
Claudia Kirk

_______________________________
Stephen Kania

_______________________________
Melissa Kennedy

_______________________________
David Bemis

_______________________________
Robert N. Moore

Accepted for the Council

_______________________________
Carolyn R. Hodges
Vice Provost and Dean of the Graduate School

(Original signatures are on file with official student records.)
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Nutritional Adequacy and Performance of Raw Food
Diets in Kittens

A Dissertation Presented for the
Doctor of Philosophy
Degree
The University of Tennessee, Knoxville

Beth Alair Hamper
August 2012
Copyright © 2012 by Beth Alair Hamper.
All rights reserved.

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ACKNOWLEDGEMENTS

I would like to thank all those who helped me complete my Doctor of Philosophy
degree in Comparative and Experimental Medicine. It has been a joint effort. I am
especially indebted to my mentors Dr. Joseph Bartges and Dr. Claudia Kirk for their
guidance and support throughout this process. I also thank Dr. Stephen Kania and Ms.
Diane Trent for their support and guidance through the laboratory portion of this
dissertation. In addition, I thank the other members of my committee, Dr. Robert Moore,
Dr. David Bemis, and Dr. Melissa Kennedy, and Dr. Arnold Saxton and Ms. Ann Reed
for their statistical support. I am grateful for financial support from the Winn Foundation
and The Milam Center, College of Veterinary Medicine, The University of Tennessee.
Lastly, I would like to dedicate this to my parents and my sister for their unwavering
support, and to all the cats who have graced me with their beauty and companionship.

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ABSTRACT

Feeding raw food diets to domestic cats is controversial. The objective of this study
was to determine if raw feline diets were nutritionally adequate for kittens and whether
they enhance immune function, reduce oxidative stress and improve digestibility.
Twenty-four 9-week-old kittens underwent a 10-week growth feeding trial with two raw
diet groups and one control group (commercial heat-processed canned diet) of eight
kittens each. Anthropomorphic measurements, feed efficiency, oxidative stress, and
blood biomarkers for innate and humoral immune function were evaluated. Additionally,
6 kittens and 4 adults participated in a 14 day digestibility trial using a 3 x 3 latin square
design. Composite fecal cultures were periodically monitored for common bacterial
pathogens.
Both raw diets passed an American Association of Feed Control Officials (AAFCO)
growth trial and had similar growth performance compared to the control diet.
Minimal differences were measured in markers of innate or humoral immune
function. Over time, higher lymphocyte and immunoglobulin responses were measured
in kittens consuming the raw diets. A trend toward higher IgM levels was noted in one
raw diet group. Higher exposure to bacterial degradation products, pathogen exposure,
or nutritional differences may have stimulated a more robust immune response in the
raw-fed groups.
No differences in levels of oxidative stress were noted among the three groups. All
kittens had decreasing levels of urinary isoprostanes over the 10-week testing period.
Significantly higher digestibility of dry matter, organic matter, protein and energy were
noted in the raw vs. control groups for both kittens and adult cats, despite similar levels
of intake. These changes may be attributed to structural changes in proteins following
processing, alterations in gastrointestinal flora, or differences in ingredient quality
among diets.
In conclusion, there was neither an advantage nor disadvantage of the two raw
feline diets when compared with the commercial heat-processed, control diet and both
diets would be deemed nutritionally adequate for feline growth based on AAFCO
feeding trials. The raw food diets were associated with higher digestibility and
decreased fecal matter. Future research on methods to reduce pathogen load while
minimizing processing of animal tissue proteins is recommended.

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TABLE OF CONTENTS

INTRODUCTION ............................................................................................................. 1
CHAPTER I ..................................................................................................................... 2
LITERATURE REVIEW ................................................................................................... 2
Unique Nutrient Requirements in Growing Kittens ..................................................... 2
Protein and amino acid requirements ................................................................... 2
Lipid and fatty acid requirements .......................................................................... 5
Carbohydrate and energy requirements ............................................................... 5
Other nutrient considerations specific to growth in kittens .................................... 6
Normal Parameters for Growth and Development in Kittens ..................................... 7
Weight gain and body composition ....................................................................... 7
Growth and development of intestinal and nutrient transporters........................... 9
Normal feline pediatric hematology and serum biochemistry parameters .......... 10
Normal Immune System Development and Response ............................................ 13
Early immune responses .................................................................................... 13
Mucosal immunity ............................................................................................... 16
Gastrointestinal microbiota development and functions ..................................... 19
Oxidative Radicals and Measurement of Oxidative Stress ...................................... 25
Raw Food Diets ....................................................................................................... 33
Risks .................................................................................................................. .33
Benefits .............................................................................................................. 38
Effects of processing on proteins and amino acids ............................................. 40
Effects of processing on vitamins ....................................................................... 55
Probiotics in Cats ..................................................................................................... 60
Hygiene Hypothesis ................................................................................................. 64
CHAPTER II ................................................................................................................. 67
EVALUATION OF RAW VS. HEAT PROCESSED DIETS ON FELINE
GROWTH ...................................................................................................................... 67
Introduction .............................................................................................................. 67
Materials and Methods ............................................................................................. 68
Animals ............................................................................................................... 69
Diet ..................................................................................................................... 69
Food intake ......................................................................................................... 70
Morphometric measurements ............................................................................. 70
Dual-energy X-ray absorptiometry ...................................................................... 70
Nutritional adequacy ........................................................................................... 71
Protein efficiency ratio and feed efficiency ratio ................................................. 71
Statistical analysis .............................................................................................. 71
Results ..................................................................................................................... 72
Morphometric measurements and body composition ......................................... 72
Serum biochemistry ............................................................................................ 82
Complete blood count ......................................................................................... 84
Feed efficiency ratio, protein efficiency ratio and body composition score ......... 86
Discussion ............................................................................................................... 90
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Conclusions ............................................................................................................. 93
CHAPTER III ................................................................................................................. 95
EVALUATION OF RAW VS. HEAT-PROCESSED DIETS ON INNATE
AND HUMORAL IMMUNE RESPONSES IN KITTENS ................................................ 94
Introduction .............................................................................................................. 94
Materials and Methods ............................................................................................. 95
Animals ............................................................................................................... 95
Diet ..................................................................................................................... 96
Innate immune function ...................................................................................... 96
Phagocytosis ................................................................................................. 97
Oxidative burst .............................................................................................. 97
Flow cytometry .............................................................................................. 97
Humoral immune function ................................................................................... 97
Serum IgG and IgM ....................................................................................... 98
Herpes Specific IgG Titers ............................................................................ 98
Statistical analysis .............................................................................................. 98
Results ..................................................................................................................... 99
Discussion ............................................................................................................. 105
Conclusions ........................................................................................................... 107
CHAPTER IV ............................................................................................................... 109
COMPARISON OF URINARY ISOPROSTANES AS A MARKER OF
OXIDATIVE STRESS IN KITTENS FED RAW VS. HEAT-PROCESSED
DIETS .......................................................................................................................... 109
Introduction ............................................................................................................ 109
Materials and Methods ........................................................................................... 110
Animals ............................................................................................................. 111
Diet ................................................................................................................... 111
Urine collection ................................................................................................. 111
Urinary creatinine measurement ....................................................................... 112
Urinary isoprostane measurement .................................................................... 112
Statistical analysis ............................................................................................ 113
Results ................................................................................................................... 113
Discussion ............................................................................................................. 116
Conclusions ........................................................................................................... 117
CHAPTER V ................................................................................................................ 118
EFFECTS OF RAW VS. HEAT-PROCESSED DIETS ON DIGESTIBILITY
IN KITTENS ................................................................................................................ 118
Introduction ............................................................................................................ 118
Materials and Methods ........................................................................................... 120
Animals ............................................................................................................. 120
Diet ................................................................................................................... 120
Food intake ....................................................................................................... 122
Digestibility trial ................................................................................................. 122
Statistical analysis ............................................................................................ 122
Results ................................................................................................................... 122
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Discussion ............................................................................................................. 125
Conclusions ........................................................................................................... 127
CHAPTER VI ............................................................................................................... 129
FECAL QUALITY IN KITTENS FED RAW VS. HEAT-PROCESSED DIETS .............. 129
Introduction ............................................................................................................ 129
Materials and Methods ........................................................................................... 130
Animals ............................................................................................................. 130
Diet ................................................................................................................... 130
Fecal collection and scoring ............................................................................. 131
Food cultures .................................................................................................... 131
Fecal cultures ................................................................................................... 131
Results ................................................................................................................... 131
Discussion ............................................................................................................. 135
Conclusions ........................................................................................................... 136
CHAPTER VII .............................................................................................................. 137
CONCLUSIONS AND RECOMMENDATIONS ........................................................... 137
REFERENCES ............................................................................................................ 139
APPENDIX .................................................................................................................. 163
VITA ............................................................................................................................ 168

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