Nutritional Adequacy and Performance of Raw Food Diets in Kittens
Total Page:16
File Type:pdf, Size:1020Kb
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 8-2012 Nutritional Adequacy and Performance of Raw Food Diets in Kittens 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 Recommended Citation 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 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. 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 equirr ements 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 studentecor r ds.) 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.) 1 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. ii 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. iii 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. iv 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 ....................................................................................................................