The Handbook of Horses and Donkeys: Introduction to Ownership and Care

Chris J. Mortensen

• Publisher: 5m Books
• Year: 2018
• eBook ISBN: 9781912178995
• Topic: Medicine
• Subtopic: Equine Veterinary Science

Horses and donkeys continue to be important to most societies as either recreational or working animals. Presenting a broad coverage of topics relating to horse and donkey ownership, The Handbook of Horses and Donkeys is an introductory guide providing expert advice on current ethical management practices.The history, evolution and domestication of equids is covered, along with equine anatomy and physiology, nutrition, behaviour, learning and cognition, communication, equine health and disease, hoof care, first aid, parasitic infections, preventive measures, pregnancy and foal management.The book is practical, guiding the reader towards good management and best practice. Functional topics are also covered, including body condition scoring, estimating body weight, calculating dietary rations, stabling, pasture advice and management of abnormal behaviours and stereotypies. The approach is holistic, with a global perspective of the care and different uses of equines worldwide and of equine health in relation to the global spread of infection and diseases.The information presented is expert-led but written in an informative and accessible way, designed to be applicable to the novice or experienced owner.

Chapter 1
History of Equidae

At the conclusion of this chapter you will be able to:

• Describe the evolution of equids over the past 55 million years
• Understand the interrelationships of both modern domestic and exotic species of Equidae
• Explain the history of domestication of horses and donkeys.

Thousands of years ago, for the first time in human history, entrepreneurs decided to lift their foot and place it over the back of a horse. During the same era, thousands of kilometers away on the continent of Africa, the same phenomenon took place, but this time they slid their foot over the back of a donkey. Thus began the special relationship we, Homo sapiens, have shared with those from the family of Equidae.

Glossary

Equidae

Noun. The taxonomic family of horses, asses, zebras or their extinct relatives.

Equid

Noun. A mammal consisting of horses, asses, zebras or their extinct relatives.

Evolution

Gradual development of living organisms with passing on of heritable characteristics over many generations.

Equine

Noun. The genus of horses, asses, zebras and more recent but now extinct relatives.

Studying how modern horses and donkeys evolved provides much insight into equid physiology and behavior. For instance, scientists have begun to uncover evidence that as far back as 3.5 million years ago (mya), early predecessors to the horse, donkey, and zebra, also suffered from the painful hoof condition known as laminitis. These findings are particularly interesting because laminitis is often viewed as a disease suffered by domestic horses and donkeys due to confinement and current management practices, when laminitis may in fact be a more common occurrence in equids than originally thought.

Other aspects of equid evolution can give us important insight into nutritional requirements and dietary habits of these animals. Early equids adapted over time to be continual grazers and developed small stomachs over many generations due to the abundant forage available. Present-day equine digestive physiology still dictates a horse or donkey eat small meals throughout a 24-hour period. Yet, current management practices are to typically only feed two large meals per day. Furthermore, domestic donkeys, or African wild asses, evolved in arid regions of Africa with less abundant forage, and their dietary requirements differ from that of a domestic horse.

Careful study of equid history also gives us insight into their skeletal structure, with changes for such things as predation avoidance or adaptation to ranging over long distances to find food. These all have had direct implications on equine temperament, and even continue to impact modern training and behavior modification techniques.

In this chapter, we will briefly cover how early ancestors of present day horses, asses (or donkeys), and zebras evolved from the small 30 kg (60 lb) Eohippus to an animal as large as a modern 1100 kg (2400 lb) Shire horse, often recognized as the largest horse breed. We will then briefly cover current theory on equid domestication.

Evolution of Today’s Modern Horses and Donkeys

The one species that is most often represented in describing evolution and evolutionary processes is that from the family of Equidae. The reasoning is due to the rich fossil history of equids found throughout the continent of North America and portions of South America, where equids evolved. The many vestiges of the lower legs and skulls of equine-related ancestors found in the geological record tell a long and storied history of these animals. Their bones provide tangible evidence linking evolutionary-driven changes with gradual modifications of equid physiology over 55 million years.

Figure 1.1. Changes in the lower leg bones and skulls of the equids. Moving from bottom to top are: Eohippus, Mesohippus, Merychippus, Hipparion, Equus, and the modern horse (E. ferus caballus). This image was published in WD Mathew’s review of horse evolution in The Quarterly Review of Biology in the year 1926.

One of the earliest scientific papers to illustrate the geological record of horses was published in 1926 (Figure 1.1). Hence, fossil evidence collected continues to support many scientific findings from the 19th and 20th centuries. Consensus has concluded that over millions of years the early equids changed from a four-toed, front-legged and three-toed, back-legged animal named Eohippus, to the single-toed, back and front legs of the present-day equids. The dimensions of the skull and structure of the teeth of the early equids also changed and are measurable. These modifications were nudged by climate change with altered food availability, thus forcing equids to adapt for basic survival in an ever-changing landscape.

Table 1.1. Taxonomic Classification of Horses, Donkeys, and Zebras.

Classification	Division	Description
Kingdom	Animalia	Multicellular organisms
Phylum	Chordata	Possess a hollow nerve chord, notochord
Class	Mammalia	Warm–blooded vertebrates; characterized by having hair and females with mammary glands
Order	Perissodactyla	Odd–toed ungulates and hind–gut fermenters; equids, rhinoceros, and tapir
Family	Equidae	Current and extinct species of horses and related animals
Genus	Equus (E.)	Current and extinct species of horses and animals related to Equus, early ancestor to modern equids
Species	E. ferus caballus; E. africanus asinus; E. quagga	Scientific name given to domestic horses, domestic donkeys, and the Plains zebra

For the purposes of this chapter, earlier ancestors of present-day horses, donkeys (asses), and zebras will be discussed as their genus (Table 1.1). That is, modern equids come from the genus Equus, their common predecessor. For each genus discussed below, there are many equine-like species that spanned across time. For example, within the genus Eohippus there are many species such as Eohippus gracilis and Eohippus uintensis. Each has slightly different body characteristics, but generally exhibits similar physiology and most likely similar behavior.

Eohippus

The earliest horse-like relative to contemporary equids has been identified as Eohippus, also called the Dawn horse (Figure 1.2). Evidence supports the theory of these small mammals being forest dwellers. The composition of recovered Eohippus skulls shows short-crowned molars demonstrating Eohippus browsed on fruit, berries, and foliage of low brush and trees during the Eocene epoch 56 to 33.9 mya. The Eocene was characterized by a very warm climate, with little to no ice caps, and dominated by wetlands, swamps, and heavy forests. Thus, available foodstuffs for the period would support a browser such as Eohippus.

Glossary

Genus

Taxonomic group containing multiple species.

Dawn horse

Common name for species of Eohippus.

Figure 1.2. Artistic rendition of what Eohippus may have looked like based on recovered fossilized skeletons. Original artwork kindly provided by Joe Richichi.

Over time, a gradual chan...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contents
• Acknowledgements
• Chapter 1 History of Equidae
• Chapter 2 The World’s Equids
• Chapter 3 Basic Equine Physiology
• Chapter 4 Breeds of Horses and Donkeys
• Chapter 5 Complexities of Horse and Donkey Behavior
• Chapter 6 Feeding Horses and Donkeys
• Chapter 7 Proper Housing and Pasture Maintenance
• Chapter 8 Equine Health
• Chapter 9 Equine Reproduction
• Appendix 1 Common Breeds Listings
• Appendix 2 Height Conversion Table
• Appendix 3 Global Population of Horses and Donkeys
• Index