Growth Of Farm

Growth of Farm Animals
Second Edition

Dedication
To our wives, Elizabeth Ray Lawrence and Janet Fowler, for their continued help
and forbearance in the writing of this second edition.

Growth of Farm Animals
Second edition

T.L.J. Lawrence
formerly of the
Faculty of Veterinary Science
University of Liverpool
UK
and

V.R. Fowler
formerly of the
Scottish Agricultural Collegeand of the Rowett Research Institute
Aberdeen
UK

CABI Publishing

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A catalogue record for this book is available from the British Library,
London, UK.
Library ofCongress Cataloging-in-Publication Data
Lawrence, T.L.J. (Tony Leonard John)
Growth of farm animals / T.L.J. Lawrence and V.R. Fowler.--2nd ed.
p. cm.
Includes bibliographical references and index.
ISBN 0-85199-484-9 (alk paper)
1. Livestock--Growth. 2. Veterinary physiology. I. Fowler, V.R.,
II. Title.
SF768.L39 2002
2002004672
ISBN 0 85199 484 9

Typeset by Columns Design Ltd, ReadingPrinted and bound in the UK by Cromwell Press, Trowbridge

Contents

Preface to First Edition
Preface to Second Edition
1 General Aspects of Growth
1.1. Introduction
1.2. Being the Right Size
1.3. Why Do Animals Change in Form as They Grow?
1.3.1. Growth of the eye
1.3.2. Growth of wings
1.3.3. The pinna of the ear
1.4. Shape and Mass
1.5. Domestication and Size of Animal
1.6.Growth and Form
1.7. Domestication and Growth
References

xi
xii
1
1
1
2
3
4
4
4
5
6
6
6

2 Cells
2.1. Introduction
2.2. Cell Structure
2.2.1. General
2.2.2. The nucleus
2.2.3. The cytoplasm
2.3. Chemical Composition of Cells
2.3.1. General
2.3.2. Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA)
2.4. Protein Synthesis and the Genetic Code
2.5. The Cell Cycle
2.6.Cellular Proliferation
2.7. Cell Hyperplasia and Hypertrophy
References

7
7
7
7
8
9
10
10
11
13
14
16
19
20

3 Tissues: Basic Structure and Growth
3.1. Introduction
3.2. Nervous Tissue
3.2.1. Introduction

21
21
21
21
v

vi

Contents

3.2.2. Structure of basic tissue: cells and fibres
3.2.3. Major divisions and development of the nervous system
3.3. ConnectiveTissue
3.3.1. Structure and classification
3.3.2. Supportive connective tissue
3.3.3. Haemopoietic connective tissue
3.3.4. Loose connective tissue
3.4. Muscle Tissue
3.4.1. Introduction
3.4.2. Structure
3.4.3. Types
3.4.4. Chemical composition of muscles
3.4.5. Muscle growth
3.5 Epithelial Tissue
3.5.1. Types and structure
3.5.2. Integument
3.5.3. Hair and wool
References

21
2323
23
27
38
38
56
56
56
63
65
67
76
76
77
77
83

4 Tissues: Growth and Structure Relative to Product Value for Human Consumption 86
4.1. Introduction
86
4.2. Carcass Yield, Composition and Quality
86
4.3. Carcass Tissues and Concepts of Meat Quality
90
4.3.1. General
90
4.3.2. From muscle in the live animal to lean meat in the carcass
90
4.3.3. From adipose tissue inthe live animal to fat in the carcass
96
4.4. Fibre Yield and Quality
98
4.4.1. General
98
4.4.2. Wool
98
4.4.3. Goat hair
100
References
101
5 Mammary Gland Growth and Product Yield
5.1. Introduction
5.2. Mammary Gland Structure
5.3. Morphogenesis
5.3.1. General features
5.3.2. Measurement of growth and size
5.3.3. Prenatal period
5.3.4. Birth
5.3.5. Prepubertal period
5.3.6....