Dietary Supplementation of Chromium Chloride and Ascorbic Acid to Alleviate the Negative Effects ...

147 Pages·2009·0.49 MB·English

Dietary Supplementation of Chromium Chloride and Ascorbic Acid to
Alleviate the Negative Effects of Heat Stress in Broiler Chicks

By

Tagwa Norain Mahmoud Basi
(B.V.Sc Nyala University)

A Thesis Submitted to the University of Khartoum in Partial
Fulfillment of the Requirements for the Degree of Master of
Veterinary Science in Physiology

Supervisor
Dr. Khalid Ibn Elwalid Ahmed Abdoun
(B.V.Sc., M.V.Sc, Ph.D.)

Department of Physiology
Faculty of Veterinary Medicine
University of Khartoum

May 2008
DEDICATION
To my lovely family;
Grandma always rocking me to finish this work
To the best of the best Mothers in the world, really she is
still giving the real unbelievable kind of love! Father, "I love
you", especially for teaching me things about life
To my brothers and my sister Tyseer.

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ABSTRACT

This study was conducted to investigate the effects of diets
supplemented with chromium chloride, CrCl .6H O (20 mg/kg basal
3 2
diet), ascorbic acid, AA (1000 mg/kg basal diet) or their combination on
the physiological performance and immune response of broiler chicks
raised under summer conditions (31.5-34.5ºC).
Dietary supplementation of AA or the combination of AA and
CrCl resulted in a significant (P < 0.05) decrease in rectal temperature.
3
The respiratory rate showed significant (P < 0.01) reduction during the
1st, 2nd, 3rd and 5th week (wk) in chicks fed on supplemented diets
compared to the control.
All supplemented diets increased BW significantly (P < 0.01)
during the last three weeks. Body weight gain was significantly
(P < 0.05) higher during the 3rd and 4th wk in all treated chicks.
All supplemented diets used in this study resulted in a significantly
(P < 0.05) higher feed intake during the 3rd week. The efficiency of feed
conversion ratio was significantly (P < 0.05) improved during during the
4th and 6th wk (P < 0.05) in all supplemented chicks.
The supplemented diets didn’t show any significant effect on liver
relative weight, however, the heart relative weight was significantly (P <
0.001) decreased. Carcass weight and dressing percentage were
significantly (P < 0.05) increased due to the treatments.
All treated chicks had higher Hb concentration values during the
last three weeks. The supplementation induced significant (P < 0.001)
reduction in heterophil/lymphocyte ratio during the 4th and 7th week.
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Inclusion of CrCl , AA or their combination significantly
3
(P < 0.01) decreased serum cholesterol level during the 3rd and 5th week.
Plasma glucose levels were lower in all treated chicks compared to the
control during the experimental period.
Supplementation with CrCl or the combination of CrCl and AA
3 3
resulted in a significant (P < 0.01) increase in serum total protein level
during the last 2 weeks compared to the control. Serum albumin levels
were significantly (P < 0.05) increased in all treated chicks during the
last three weeks.
The supplementation resulted in a significant (P < 0.001) increase
in serum insulin level during the 4th and 7th week. Serum cortisol level in
chicks fed on supplemental diets was significantly (P < 0.001) lower
during the 4th and 7th weeks compared to the control.
The supplementation with CrCl , AA or their combination resulted
3
in a significant (P < 0.05) reduction of serum osmolality during the last 4
weeks.
The supplementation significantly (P < 0.05) improved Newcastle
disease virus (NDV) antibody titer during the 3rd and 5th week.
The present results indicate that dietary supplementation with
CrCl , AA or their combination could be used to alleviate the negative
3
effects of heat stress and to improve the performance and immune
response of broiler chicks.
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ACKNOWLEDGEMENTS

I would like first to raise my thanks to Allah for giving me the
health and the knowledge to achieve the faith to believe and the courage
to succeed in all the parts of my endeavors. Without Allah's help and
countless hours of prayer, I know that this work would not have been
possible.
I would like to give a very special thanks to my former supervisor
Dr. Izzeldin Babikir Ismail for giving innumerable chances to prove my
skills and my dedication to this programme, I know that we have had an
incredibly hard time over the past two years; I deeply respect and admire
him as a mentor and a person. He has taught me more than he will ever
know not only about physiology, but also about how life is going on.
Thanks is also extended to my supervisor Dr. Khalid Ibn Elwalid Ahmed
Abdoun to whom I would like to express my deepest thanks and
appreciations.
Deep thanks and appreciation is extended to the Head of the
Department Dr. Abdalla Mohammed Abdelatif. My special thanks is due
to the staff members of the Department of Physiology, Faculty of
Veterinary Medicine, University of Khartoum and my colleagues in the
postgraduate studies.
I would like also to thank the University of Nayala for offering me
this chance and their financial support.
I extend my thanks and gratitude to Dr. Nagi I. Ali, Waleed Y.
Mousa and Isam Hamed for their help.
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TABLE OF CONTENTS

Subject Page
DEDICATION …………………………………………………………….. i
ABSTRACT ……………………………………………………………….. ii
ACKNOWLEDGEMENTS ……………………………………………….. iv
TABLE OF CONTENTS ………………………………………………….. v
LIST OF TABLES ………………………………………………………… viii
LIST OF FIGURES ……………………………………………………….. xi
GENERAL INTRODUCTION ……………………………………………. 1
CHAPTER ONE: LITERATURE REVIEW …………………………... 4
1.1 Heat stress in poultry …………………………………………..... 4
1.2 Thermoregulation ………………………………………………... 6
1.3 Cardiovascular response and blood composition during
hyperthermia …………………………………………………….. 7
1.4 Chromium ………..…………………………………………….. 9
1.4.1 Chemical properties ……………………………………………... 9
1.4.2 Absorption ……….……………………………………………… 10
1.4.3 Transport ………………………………………………………… 12
1.4.4 Excretion ………………………………………………………… 13
1.4.5 Chromium concentration in blood .……………………………… 14
1.4.6 Chromium concentration in tissues ……………………………… 15
1.4.7 Chromium function ……………………………………………… 16
1.4.8 The role of chromium in metabolism …………………………… 18
1.4.8.1 Carbohydrates metabolism ……………………………………… 18
1.4.8.2 Lipids metabolism ………………………………………………. 19
1.4.8.3 Proteins metabolism …………………………………………….. 20
1.4.9 Regulation of hormones ………………………………………… 20
1.4.9.1 Cortisol ………………………………………………………….. 20
1.4.9.2 Insulin …………………………………………………………… 21
1.4.10 Immune function ………………………………………………… 22
1.4.11 Chromium toxicity ………………………………………………. 24
1.5 Chromium in poultry ……………………………………………. 25
1.5.1 Trivalent chromium ……………………………………………... 26
1.5.2 Chromium enhancing effects ……………………………………. 26
1.5.3 Immune system ………………………………………………….. 29
1.6 Ascorbic acid……………………………………………………. 30
1.6.1 Ascorbic acid in poultry …………………………………………. 31
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1.6.2 Ascorbic acid enhancing effects ………………………………… 32
1.6.3 Immune system ………………………………………………….. 32
CHAPTER TWO: MATERIALS AND METHODS …………………... 35
2.1 Experimental house ……………………………………………… 35
2.2 Experimental birds ………………………………………………. 35
2.3 Experimental feeds ……………………………………………… 36
2.4 Experimental design …………………………………………….. 36
2.5 Experimental plan ……………………………………………….. 36
2.6 Measurements of production parameters ………………………... 39
2.6.1 Feed intake ………………………………………………………. 39
2.6.2 Body weight ……………………………………………………... 40
2.6.3 Body weight gain ………………………………………………... 40
2.6.4 Feed conversion ratio (FCR) ……………………………………. 40
2.7 Physiological responses …………………………………………. 40
2.7.1 Ambient temperature and relative humidity …………………….. 40
2.7.2 Rectal temperature ………………………………………………. 42
2.7.3 Respiratory rate ………………………………………………….. 42
2.8 Blood sampling and analysis ……………………………………. 42
2.8.1 Haemoglobin determination …………………………………….. 43
2.8.2 Packed cell volume (PCV)………………………………………. 44
2.8.3 Differential leucocytes count ……………………………………. 44
2.8.4 Analysis of blood chemistry …………………………………….. 45
2.8.4.1 Plasma glucose …………………………………………………... 45
2.8.4.2 Serum cholesterol ……………………………………………….. 46
2.8.4.3 Serum total protein ………………………………………………. 48
2.8.4.4 Serum albumin …………………………………………………... 49
2.8.4.5 Serum insulin ……………………………………………………. 50
2.8.4.6 Serum cortisol …………………………………………………… 51
2.8.4.7 NDV antibody titer ……………………………………………… 53
2.8.4.8 Serum osmolality ………………………………………………... 54
2.9 Post-slaughtering measurement …………………………………. 55
2.9.1 Carcass weight and dressing percentage ………………………… 55
2.9.2 Relative weight of visceral organs ….…………………………… 55
2.10 Statistical Analysis ………………………………………………. 55
CHAPTER THREE: RESULTS ………………………………………… 56
3.1 Physiological response ………………………………………….. 56
3.1.1 Rectal temperature ………………………………………………. 56
3.1.2 Respiratory rate ………………………………………………….. 56
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3.2 Body weight ……………………………………………………... 56
3.3 Body weight gain ………………………………………………... 59
3.4 Feed intake ………………………………………………………. 59
3.5 Feed conversion ratio ……………………………………………. 64
3.6 Carcass weight and dressing percentage ………………………… 64
3.7 Liver and heart relative weights …………………………………. 64
3.8 Blood analysis …………………………………………………… 69
3.8.1 Blood composition ………………………………………………. 69
3.8.1.1 Packed cell volume ……………………………………………… 69
3.8.1.2 Heterophils/lymphocyte ratio …………………………………… 69
3.8.1.3 Blood heamoglubin concentration ………………………………. 69
3.8.2 Plasma and serum metabolites …………………………………... 73
3.8.2.1 Plasma glucose …………………………………………………... 73
3.8.2.2 Serum cholesterol ……………………………………………….. 73
3.8.2.3 Serum total protein ………………………………………………. 73
3.8.2.4 Serum albumin …………………………………………………... 77
3.8.2.5 Serum osmolality ………………………………………………... 77
3.8.2.6 NDV antibody titer ……………………………………………… 80
3.8.2.7 Serum insulin and cortisol ………………………………………. 80
Summary…………………………………………………………. 84
CHAPTER FOUR: DISCUSSION AND CONCLUSION …………… 86
4.1 Discussion ……………………………………………………….. 86
4.2 Conclusions ……………………………………………………… 93
REFERENCES …………………………………………………………… 95
ARABIC ABSTRACT

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LIST OF TABLES
Table No. Page
1. Ingredients of basal starter and finisher feed (%) ....… 37
2. Nutrient composition of basal starter and finisher feed 38
3. Average weekly values of minimum, maximum and
mean ambient temperature (°C) and relative humidity
(%) during the experimental period (May – July
2007) .………………………………………………. 41
4. Assay procedure of cortisol .……………………….. 53
5. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on weekly rectal
temperature, T (°C) in broiler chicks raised under
r
summer conditions (mean±SD) …………………….. 57
6. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on weekly respiratory
rate, RR (breaths/ min) in broiler chicks raised under
summer conditions (mean±SD) …………………….. 58
7. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on weekly feed intake
(g/bird) in broiler chicks raised under summer
conditions (mean±SD) …………………………….... 62
8. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
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mg/kg) or their combination on weekly feed
conversion ratio, FCR (g feed/g gain) in broiler
chicks raised under summer conditions (mean±SD) .. 65
9. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on weekly packed cell
volume, PCV (%) in broiler chicks raised under
summer conditions ( mean±SD) ……………………. 70
10. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on haemoglobin (Hb)
concentration (g/dL) in broiler chicks raised under
summer conditions (mean±SD) …………………….. 72
11. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on weekly plasma
glucose concentration (mg/dl) in broiler chicks raised
under summer condition (mean±SD) ……………….. 74
12. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
mg/kg) or their combination on weekly serum
cholesterol concentration (mg/dl) in broiler chicks
raised under summer conditions (mean±SD) ………. 75
13. Effect of dietary supplementation with chromium
chloride, CrCl (20 mg/kg), Ascorbic acid, AA (1000
3
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