Hawkey's Atlas of Wild and Exotic Animal Haematology

Jaime Samour, Mike Hart

• Publisher: CRC Press
• Year: 2020
• ISBN:
  9781000190922
• Edition: 1
• Topic: Ciencias biológicas
• Subtopic: Zoología

This revised, updated and expanded edition of Christine Hawkey's A Colour Atlas of Comparative Veterinary Haematology is bursting with high-quality images to aid identification of blood cells and haemoparasites in the different species commonly seen in private practice and zoological collections. It will assist veterinarians in the identification of normal and abnormal blood cells and in understanding the structural differences of blood cells between the various taxa within the Animal Kingdom. With the help of this guide, readers will be able to understand haemoresponses in the presence of specific and non-specific disease processes and identify haemoparasites commonly seen in blood films from wild and exotic animals.

This impressively illustrated comparative haematology atlas is unrivalled in its scope, quality and accuracy. It is a must-have for veterinary students, veterinary surgeons working in general and referral veterinary clinical practices, clinicians working in zoological collections and specialists in exotic animal medicine.

1
General Introduction

1.1 Introduction to Haematology

‘Blood is the most complex fluid known to man.’

Dr Christine M Hawkey (1931–2008)

Haematology is an important component of clinical laboratory diagnosis and plays a prominent role in differential diagnosis, in monitoring the progress of therapeutic protocols and in providing an educated prognosis. Examination of a stained blood film is an integral part and, many would argue, the most essential assay of any routine haematological examination. In very small animals, where the amount of blood is limited, it may be the only procedure that can be undertaken. The ability to distinguish between normal and abnormal changes in blood cell morphology and to interpret these in terms of their pathological significance is one of the primary tasks of the haematologist.

For haematologists undertaking comparative assessments between different species this task is not easy, because of the large number of species involved. For each of these an understanding is needed of the normal blood cell morphology and how this is influenced by different pathological processes. Although similar principles are probably involved in all animals, in practical terms, it can be extremely difficult to apply them when faced with the problem of assessing the blood film from less common species of mammals, birds, reptiles, amphibians, fish or invertebrates.

Clearly, it is not possible to provide a complete description of normal and abnormal blood cells of all species in one volume, even if this information were available. The blood cells of humans have been extensively illustrated, and there are several existing books devoted to the blood and bone marrow cells of domesticated and laboratory animals, which concentrate mainly on presenting detailed information for individual species. The approach used in this Atlas is somewhat different. We believe that it is valuable to present a comparative study of the morphology of blood cells of different species. By doing this, it is possible to demonstrate some of the basic principles influencing the responses of blood cells to pathological insults and diseases, which would contribute to the understanding of health and diseases in individuals. This eventually should create a situation where interpretation of blood films of sick individuals of any species can be undertaken from an informed background, whether or not the interpreter is familiar with the species in question.

All haematologists would realise that there are many potential drawbacks to this approach. Technical problems created by the difficulty of ensuring standardization of fixation and of staining methods are inevitable, particularly as the materials and methods used by many laboratories can be different and are based on methods used in human haematology. The variations can produce false indications of species similarities and differences. In fact, morphological differences do exist in the normal blood cells of different species, obviously so with regard to the red cells of mammals when compared with those of other species and, perhaps less obviously so, when considering white cell morphology, even among mammals. Many of these differences are illustrated in this Atlas, with the aim of providing some insight into the range of variation which can be considered normal. Inclusion of this normal material should also render the Atlas of interest to medical technologists, comparative physiologists, cell biologists and taxonomists.

The images of this Atlas are originated from blood samples obtained from free-living animals, from specimens housed in zoological collections and from individuals seen by Veterinary Surgeons working in clinical practice from at least 15 different countries. In addition, over 400 slides used to produce the previous publication of the Atlas, were scanned and converted into digital images and are also included in this new publication. The previous publication of this Atlas included over 125 images of blood cells from domestic animals as this was produced as an Atlas of Comparative Veterinary Haematology. In this new publication, even though the content is about wild and exotic animal haematology, we decided to leave the images from domestic species for comparative purposes. The normal blood cells illustrated in the Atlas are from specimens declared clinically normal after examination from qualified Veterinary Surgeons at the time when the sample was obtained. Although several of the individuals were in the natural environment, there is as yet no evidence that blood cell morphology would be influenced by this fact.

The abnormal cells shown, in most instances, are from clinical cases in which the diagnosis was indicated by clinical examination, response to treatment and, on some occasions, post-mortem and histopathological examination. We have also included examples of cells which are clearly abnormal but where a definitive diagnosis was not made. This has been done to extend the recognition range of abnormal variation and, more importantly, with the hope of stimulating users of the Atlas to ponder upon the possible pathological significance of these cells and/or the changes observed.

Each section of the Atlas is introduced by a description of the comparative morphology, relationships and function of the cells in different species and comments upon possible primary and secondary pathological variations. Within each section, an attempt has been made to demonstrate the range of morphological variation considered to be normal in mammals, birds, reptiles, amphibians, fish and invertebrates, followed by examples of morphological variations associated with different disease processes. Each figure is accompanied by a descriptive legend and, where relevant, by details of cell counts and other haematology changes. As the main objective of the Atlas is to aid with the identification of blood cells in different species, the figures have been grouped together according to the phylogeny of the specimens in which they were identified. Specimens depicted in the Atlas are referred to by their common English names followed by their scientific names to assist in the identification for a more international audience. Unless otherwise stated, blood films were prepared using venous blood stored in commercially available tubes containing ethylenediaminetetraacetic acid (EDTA) and fixed with acetone-free absolute methanol using either May-Grünwald-Giemsa stain or Wright-Giemsa stain, or by using commercially available rapid stain kits such as Diff Quik™. In most instances blood cells were photographed at a magnification of ×100 or ×40.

1.2 History of Haematology

1.2.1 Introduction

Haematology saw its early beginning in ancient Egypt with the practice of draining blood from human patients with the intention of healing a condition or a symptom. This technique was widely employed by physicians throughout the Middle Ages, and it was simply known as bloodletting. During this period, the earliest written record of the use of bloodletting in human medicine can be credited to the Italian physician Prospero Alpini (1553–1617) in his work ‘De Medicina Aegyptiorum’.

1...

Table of contents

• Cover
• Half-Title
• Title
• Copyright
• Dedication
• Contents
• Foreword
• Preface
• Acknowledgements
• About the Editors
• Contributors
• In Memoriam
• 1 General Introduction
• SECTION A Basic Wild and Exotic Animal Haematology
• SECTION B Atlas of Wild and Exotic Animal Haematology
• SECTION C Atlas of Wild and Exotic Animal Blood Parasites
• SECTION D Appendix: Normal Haematology Reference Values in Selected Wild and Exotic Animals
• Appendix
• Bibliography
• Index