Difference between revisions of "Animal husbandry" - New World Encyclopedia

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[[Image:Karjus.jpg|right|thumb|left|250px|A man [[herding]] [[goat]]s in [[Tunisia]].]]
 
[[Image:Karjus.jpg|right|thumb|left|250px|A man [[herding]] [[goat]]s in [[Tunisia]].]]
  
The first [[animal]]s to be [[Animal husbandry#domestication|domesticated]] were [[sheep]], [[goat]]s, [[pig]]s, [[cattle]], and [[horse]]s in ancient [[Middle East]]ern and [[Asia]]n societies. The domestication of these animals marked an important watershed in the [[history of agriculture]] as it allowed societies to move away from [[hunter-gatherer|hunter-gathering]] traditions.<ref>"animal husbandry." The Columbia Electronic Encyclopedia, Sixth Edition. Columbia University Press., 2003. Answers.com 29 Sep. 2007.[[http://www.answers.com/topic/animal-husbandry]]</ref>Early agriculturists used animals extensively for [[labor]], [[food]], and raw materials, but also realized, without the help of our modern understanding of [[genetics]], that specific breeding practices could potentially yield more beneficial traits in animal offsprings. Their methods of breeding were based solely on observable traits, so that animals with obviously beneficial traits were bred to produce offspring with combined desirable characteristics.<ref> (2005) World of Genetics [[http://www.bookrags.com/research/animal-husbandry-wog/"Animal Husbandry"]] Retrieved September 17, 2007 </ref> Commonly this was achieved by pairing two desirable animals during times of female [[ovulation]], and allowing the animals to breed. However, since two healthy animals will not always breed on their own, [[artificial insemination]] was employed, first by the [[Arab]]s in fourteenth century. Others attempted similar techniques, particularly early [[Europe]]an scientists interested in genetics<ref> (2005) World of Invention [[http://www.bookrags.com/Animal_husbandry#brcopybox"Animal Breeding"]] Retrieved September 17, 2007 </ref> While these methods were sophisticated for the times they were used, they often produced mixed results.  
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The first [[animal]]s to be [[Animal husbandry#domestication|domesticated]] were [[sheep]], [[goat]]s, [[pig]]s, [[cattle]], and [[horse]]s in ancient [[Middle East]]ern and [[Asia]]n societies. The domestication of these animals marked an important watershed in the [[history of agriculture]] as it allowed societies to move away from [[hunter-gatherer|hunter-gathering]] traditions.<ref>"animal husbandry." The Columbia Electronic Encyclopedia, Sixth Edition. Columbia University Press., 2003. Answers.com 29 Sep. 2007.[http://www.answers.com/topic/animal-husbandry]</ref>Early agriculturists used animals extensively for [[labor]], [[food]], and raw materials, but also realized, without the help of our modern understanding of [[genetics]], that specific breeding practices could potentially yield more beneficial traits in animal offsprings. Their methods of breeding were based solely on observable traits, so that animals with obviously beneficial traits were bred to produce offspring with combined desirable characteristics.<ref> (2005) World of Genetics [http://www.bookrags.com/research/animal-husbandry-wog/"Animal Husbandry"] Retrieved September 17, 2007 </ref> Commonly this was achieved by pairing two desirable animals during times of female [[ovulation]], and allowing the animals to breed. However, since two healthy animals will not always breed on their own, [[artificial insemination]] was developed, first employed by the [[Arab]]s in fourteenth century. Others attempted similar techniques, particularly early [[Europe]]an scientists interested in genetics.<ref> (2005) World of Invention [http://www.bookrags.com/Animal_husbandry#brcopybox"Animal Breeding"] Retrieved September 17, 2007 </ref> While these methods were sophisticated for the times they were used, they often produced mixed results.  
  
In the twentieth century, with the advent of genetic science, the manipulation of animal genes with the desired result of more advantageous offspring became more successful. By understanding the mechanics of genetic transmission from parent to offspring, scientists were able to breed animals in a more precise manner. Coupled with new advances in general veterinary science, [[nutrition]], and the commercialization of farms, animal husbandry became more systematic so as to yield higher quality animals, in shorter time frames, and for less money. However, reason trends have also attempted to bring in older traditions involving [[emotion]]al care and attachment to the animals cared for the benefit of their development.<ref>"animal husbandry." The Veterinary Dictionary. Elsevier, 2007. Answers.com 29 Sep. 2007. [[http://www.answers.com/topic/animal-husbandry]]</ref>
+
In the twentieth century, with the advent of genetic science, the manipulation of animal genes with the desired result of more advantageous offspring became more successful. By understanding the mechanics of genetic transmission from parent to offspring, scientists were able to breed animals in a more precise manner. Coupled with new advances in general veterinary science, [[nutrition]], and the commercialization of farms, animal husbandry became more systematic so as to yield higher quality animals, in shorter time frames, and for less money. More recent trends have also attempted to bring in older traditions involving [[emotion]]al care and attachment to the animals cared for the benefit of their development.<ref>"animal husbandry." The Veterinary Dictionary. Elsevier, 2007. Answers.com 29 Sep. 2007. [[http://www.answers.com/topic/animal-husbandry]]</ref>
  
 
==Domestication==
 
==Domestication==
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Human beings have brought these populations under their care for a wide range of reasons: to produce [[food]] or valuable [[commodity|commodities]] (such as [[wool]], [[cotton]], or [[silk]]), for help with various types of [[Labor (economics)|work]], [[transportation]], and to enjoy as [[pet]]s or [[ornamental plant]]s. Animals domesticated for home companionship are usually called ''pets'' while those domesticated for food or work are called ''[[livestock]]'' or ''farm animals''.
 
Human beings have brought these populations under their care for a wide range of reasons: to produce [[food]] or valuable [[commodity|commodities]] (such as [[wool]], [[cotton]], or [[silk]]), for help with various types of [[Labor (economics)|work]], [[transportation]], and to enjoy as [[pet]]s or [[ornamental plant]]s. Animals domesticated for home companionship are usually called ''pets'' while those domesticated for food or work are called ''[[livestock]]'' or ''farm animals''.
  
According to [[evolutionary biology|evolutionary biologist]] [[Jared Diamond]].<ref> Diamond, Jared. "Guns, Germs and Steel: The Fates of Human Societies" (Norton, 1999) ISBN 0393317552</ref>, animal species must meet six criteria in order to be considered for domestication:
+
According to [[evolutionary biology|evolutionary biologist]] [[Jared Diamond]],<ref> Diamond, Jared. "Guns, Germs and Steel: The Fates of Human Societies" (Norton, 1999) ISBN 0393317552</ref> animal species must meet six criteria in order to be considered for domestication:
  
 
#Flexible [[diet (nutrition)|diet]]—Creatures that are willing to consume a wide variety of food sources and can live off less cumulative food from the [[food pyramid]] (such as [[corn]] or [[wheat]]) are less expensive to keep in [[captivity]]. Most [[carnivore]]s can only be fed [[meat]], which requires the expenditure of many [[herbivore]]s.
 
#Flexible [[diet (nutrition)|diet]]—Creatures that are willing to consume a wide variety of food sources and can live off less cumulative food from the [[food pyramid]] (such as [[corn]] or [[wheat]]) are less expensive to keep in [[captivity]]. Most [[carnivore]]s can only be fed [[meat]], which requires the expenditure of many [[herbivore]]s.
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#Pleasant disposition—Large creatures that are [[Aggression|aggressive]] toward humans are dangerous to keep in captivity. The [[African buffalo]] has an unpredictable nature and is highly dangerous to humans. Although similar to domesticated [[pig]]s in many ways, American [[peccary|peccaries]] and Africa's [[warthog]]s and [[bushpig]]s are also dangerous in captivity.
 
#Pleasant disposition—Large creatures that are [[Aggression|aggressive]] toward humans are dangerous to keep in captivity. The [[African buffalo]] has an unpredictable nature and is highly dangerous to humans. Although similar to domesticated [[pig]]s in many ways, American [[peccary|peccaries]] and Africa's [[warthog]]s and [[bushpig]]s are also dangerous in captivity.
 
#[[Temperament]] which makes it unlikely to [[panic]]—A creature with a nervous disposition is difficult to keep in captivity as they will attempt to flee whenever they are startled. An animal such as the [[gazelle]] which is very flighty and has a powerful leap that allows it to escape an enclosed pen is not suitable for domestication.
 
#[[Temperament]] which makes it unlikely to [[panic]]—A creature with a nervous disposition is difficult to keep in captivity as they will attempt to flee whenever they are startled. An animal such as the [[gazelle]] which is very flighty and has a powerful leap that allows it to escape an enclosed pen is not suitable for domestication.
#Modifiable [[social hierarchy]]—Social creatures that recognize a hierarchy of dominance can be raised to recognize a human as its pack [[Leadership|leader]]. [[Bighorn sheep]] cannot be herded because they lack a dominance hierarchy, whilst [[antelope]]s and [[giant forest hog]]s are territorial when breeding and cannot be maintained in crowded enclosures in captivity.<ref> Diamond, Jared. "Guns, Germs and Steel: The Fates of Human Societies" (Norton, 1999) ISBN 0393317552</ref>
+
#Modifiable [[social hierarchy]]—Social creatures that recognize a hierarchy of dominance can be raised to recognize a human as its pack [[Leadership|leader]]. [[Bighorn sheep]] cannot be herded because they lack a dominance hierarchy, whilst [[antelope]]s and [[giant forest hog]]s are territorial when breeding and cannot be maintained in crowded enclosures in captivity.
  
 
=== Limits of domestication ===
 
=== Limits of domestication ===
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==Hybridization and genetic engineering==
 
==Hybridization and genetic engineering==
  
The [[green revolution]] popularized the use of conventional [[hybridization]] to greatly increase yield s. Often the handful of breeds of animals hybridized originated in developed countries and were further hybridized with local varieties in the rest of the developing world, to create high yield strains resistant to local climate and diseases. Local governments and industry since have been pushing hybridization with such zeal that several of the wild and indigenous breeds evolved locally over thousands of years, having high resistance to local extremes in climate and immunity to diseases, have already become extinct or are in grave danger of becoming so in the near future. Due to complete disuse because of un-profitability and uncontrolled intentional, compounded with unintentional, crossbreeding (genetic pollution) formerly huge gene pools of various wild and indigenous breeds have collapsed causing widespread [[genetic erosion]] and genetic pollution resulting in great loss in genetic diversity and biodiversity as a whole.<ref>[http://www.farmedia.org/bulletins/bulletin28.html “Genetic Pollution: The Great Genetic Scandal”] Retrieved September 29, 2007.</ref>
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Animals of domestic origin as well as [[feral]] animals sometimes produce fertile hybrids with native, wild animals which leads to [[genetic pollution]] in the naturally evolved wild gene pools, many times threatening rare species with [[extinction]]. Cases include the [[mallard duck]], wild [[boar]], the [[rock dove]] or pigeon, the Red Junglefowl (Gallus gallus) (ancestor of all chickens), and [[carp]]. Another example is the [[dingo]], itself an early feral dog, which hybridizes with dogs of European origin.
 
 
Animals of domestic origin as well as [[feral]] animals sometimes produce fertile hybrids with native, wild animals which leads to [[genetic pollution]] in the naturally evolved wild gene pools, many times threatening rare species with [[extinction]]. Cases include the [[mallard duck]], wild [[boar]], the [[rock dove]] or pigeon, the Red Junglefowl (Gallus gallus) (ancestor of all chickens), and [[carp]]. Another example is the [[dingo]], itself an early feral dog, which hybridizes with dogs of European origin. On the other hand, genetic pollution seems not to be noticeable in the [[rabbit]].
 
  
 
Genetic pollution is a serious issue:
 
Genetic pollution is a serious issue:
 
<blockquote>Living organisms can also be defined as pollutants, when a non-indigenous species (plant or animal) enters a habitat and modifies the existing equilibrium among the organisms of the affected ecosystem (sea, lake, river). Non-indigenous, including transgenic species (GMOs), may bring about a particular version of pollution in the vegetal kingdom: so-called genetic pollution. This term refers to the uncontrolled diffusion of genes (or transgenes) into genomes of plants of the same type or even unrelated species where such genes are not present in nature.  For example, a grass modified to resist herbicides could pollinate conventional grass many miles away, creating weeds immune to the most widely used weed-killer, with obvious consequences for crops. Genetic pollution is at the basis of the debate on the use of GMOs in agriculture.<ref>[http://www.scienzagiovane.unibo.it/English/pollution/2-facets.html The many facets of pollution] Bologna University web site for Science Communication. Retrieved September 29, 2007. </ref></blockquote>
 
<blockquote>Living organisms can also be defined as pollutants, when a non-indigenous species (plant or animal) enters a habitat and modifies the existing equilibrium among the organisms of the affected ecosystem (sea, lake, river). Non-indigenous, including transgenic species (GMOs), may bring about a particular version of pollution in the vegetal kingdom: so-called genetic pollution. This term refers to the uncontrolled diffusion of genes (or transgenes) into genomes of plants of the same type or even unrelated species where such genes are not present in nature.  For example, a grass modified to resist herbicides could pollinate conventional grass many miles away, creating weeds immune to the most widely used weed-killer, with obvious consequences for crops. Genetic pollution is at the basis of the debate on the use of GMOs in agriculture.<ref>[http://www.scienzagiovane.unibo.it/English/pollution/2-facets.html The many facets of pollution] Bologna University web site for Science Communication. Retrieved September 29, 2007. </ref></blockquote>
  
A [[Genetically Modified Organism]] (GMO) is an [[organism]] whose [[gene]]tic material has been [[genetic engineering|altered]] using the genetic engineering techniques generally known as [[recombinant DNA technology]]. Genetic Engineering today has become another serious and alarming cause of genetic pollution because artificially created and genetically engineered animals in laboratories, which could never have evolved in nature even with conventional hybridization, can live and breed on their own and what is even more alarming interbreed with naturally evolved wild varieties.
+
A [[Genetically Modified Organism]] (GMO) is an [[organism]] whose [[gene]]tic material has been [[genetic engineering|altered]] using the genetic engineering techniques generally known as [[recombinant DNA technology]]. Genetic Engineering today has become another serious and alarming cause of genetic pollution because artificially created and genetically engineered animals in laboratories, which could never have evolved in nature even with conventional hybridization, can live and breed on their own and, what is even more alarming, interbreed with naturally evolved wild varieties.  
 
 
It is feared that genetic erosion, coupled with genetic pollution, will destroy that needed unique genetic base thereby creating an unforeseen hidden crisis which will result in a severe threat to our food security for the future when diverse genetic material will cease to exist to be able to further improve or hybridize weakening livestock against more resistant diseases and climatic changes.
 
  
 
[[Image:Reindeer milking.jpg|thumb|right|250px|[[Reindeer]] being milked by [[Sami people]].]]
 
[[Image:Reindeer milking.jpg|thumb|right|250px|[[Reindeer]] being milked by [[Sami people]].]]

Revision as of 15:18, 23 October 2007


Shepherd with his sheep in Făgăraş Mountains, Romania.

Animal husbandry, also known as animal science, is the agricultural practice of breeding and raising livestock. An outgrowth of agricultural practices and techniques of farmers for centuries, the commercialization of agriculture and the advances of veterinary science during the twentieth century helped to establish a recognized scientific discipline that is taught in many universities and colleges and used all over the world.

History

A man herding goats in Tunisia.

The first animals to be domesticated were sheep, goats, pigs, cattle, and horses in ancient Middle Eastern and Asian societies. The domestication of these animals marked an important watershed in the history of agriculture as it allowed societies to move away from hunter-gathering traditions.[1]Early agriculturists used animals extensively for labor, food, and raw materials, but also realized, without the help of our modern understanding of genetics, that specific breeding practices could potentially yield more beneficial traits in animal offsprings. Their methods of breeding were based solely on observable traits, so that animals with obviously beneficial traits were bred to produce offspring with combined desirable characteristics.[2] Commonly this was achieved by pairing two desirable animals during times of female ovulation, and allowing the animals to breed. However, since two healthy animals will not always breed on their own, artificial insemination was developed, first employed by the Arabs in fourteenth century. Others attempted similar techniques, particularly early European scientists interested in genetics.[3] While these methods were sophisticated for the times they were used, they often produced mixed results.

In the twentieth century, with the advent of genetic science, the manipulation of animal genes with the desired result of more advantageous offspring became more successful. By understanding the mechanics of genetic transmission from parent to offspring, scientists were able to breed animals in a more precise manner. Coupled with new advances in general veterinary science, nutrition, and the commercialization of farms, animal husbandry became more systematic so as to yield higher quality animals, in shorter time frames, and for less money. More recent trends have also attempted to bring in older traditions involving emotional care and attachment to the animals cared for the benefit of their development.[4]

Domestication

File:Shepherd&Dog.jpg
Dogs and sheep were among the first animals to be domesticated.

Domestication refers to the process of taming a population of animals (although it can also be used to refer to plants) or even a species as a whole. Human beings have brought these populations under their care for a wide range of reasons: to produce food or valuable commodities (such as wool, cotton, or silk), for help with various types of work, transportation, and to enjoy as pets or ornamental plants. Animals domesticated for home companionship are usually called pets while those domesticated for food or work are called livestock or farm animals.

According to evolutionary biologist Jared Diamond,[5] animal species must meet six criteria in order to be considered for domestication:

  1. Flexible diet—Creatures that are willing to consume a wide variety of food sources and can live off less cumulative food from the food pyramid (such as corn or wheat) are less expensive to keep in captivity. Most carnivores can only be fed meat, which requires the expenditure of many herbivores.
  2. Reasonably fast growth rate—Fast maturity rate compared to the human life span allows breeding intervention and makes the animal useful within an acceptable duration of caretaking. Large animals such as elephants require many years before they reach a useful size.
  3. Ability to be bred in captivity—Creatures that are reluctant to breed when kept in captivity do not produce useful offspring, and instead are limited to capture in their wild state. Creatures such as the panda and cheetah are difficult to breed in captivity.
  4. Pleasant disposition—Large creatures that are aggressive toward humans are dangerous to keep in captivity. The African buffalo has an unpredictable nature and is highly dangerous to humans. Although similar to domesticated pigs in many ways, American peccaries and Africa's warthogs and bushpigs are also dangerous in captivity.
  5. Temperament which makes it unlikely to panic—A creature with a nervous disposition is difficult to keep in captivity as they will attempt to flee whenever they are startled. An animal such as the gazelle which is very flighty and has a powerful leap that allows it to escape an enclosed pen is not suitable for domestication.
  6. Modifiable social hierarchy—Social creatures that recognize a hierarchy of dominance can be raised to recognize a human as its pack leader. Bighorn sheep cannot be herded because they lack a dominance hierarchy, whilst antelopes and giant forest hogs are territorial when breeding and cannot be maintained in crowded enclosures in captivity.

Limits of domestication

Hereford cattle, domesticated for beef production

A herding instinct arguably aids in domesticating animals: tame one and others will follow, regardless of chiefdom. Yet, despite long enthusiasm about revolutionary progress in farming, few crops and probably even fewer animals ever became domesticated.

Domesticated species, when bred for tractability, companionship, or ornamentation rather than for survival, can often fall prey to disease: several sub-species of apples and cattle, for example, face extinction; and many dogs with very respectable pedigrees appear prone to genetic problems.

Domestication has also threatened human beings with disease. Cattle have given people various viral poxes, measles, and tuberculosis; pigs gave influenza; and horses the rhinoviruses. Humans share over sixty diseases with dogs. Many parasites also have their origins in domestic animals.

Hybridization and genetic engineering

Animals of domestic origin as well as feral animals sometimes produce fertile hybrids with native, wild animals which leads to genetic pollution in the naturally evolved wild gene pools, many times threatening rare species with extinction. Cases include the mallard duck, wild boar, the rock dove or pigeon, the Red Junglefowl (Gallus gallus) (ancestor of all chickens), and carp. Another example is the dingo, itself an early feral dog, which hybridizes with dogs of European origin.

Genetic pollution is a serious issue:

Living organisms can also be defined as pollutants, when a non-indigenous species (plant or animal) enters a habitat and modifies the existing equilibrium among the organisms of the affected ecosystem (sea, lake, river). Non-indigenous, including transgenic species (GMOs), may bring about a particular version of pollution in the vegetal kingdom: so-called genetic pollution. This term refers to the uncontrolled diffusion of genes (or transgenes) into genomes of plants of the same type or even unrelated species where such genes are not present in nature. For example, a grass modified to resist herbicides could pollinate conventional grass many miles away, creating weeds immune to the most widely used weed-killer, with obvious consequences for crops. Genetic pollution is at the basis of the debate on the use of GMOs in agriculture.[6]

A Genetically Modified Organism (GMO) is an organism whose genetic material has been altered using the genetic engineering techniques generally known as recombinant DNA technology. Genetic Engineering today has become another serious and alarming cause of genetic pollution because artificially created and genetically engineered animals in laboratories, which could never have evolved in nature even with conventional hybridization, can live and breed on their own and, what is even more alarming, interbreed with naturally evolved wild varieties.

Reindeer being milked by Sami people.
American Cowboy circa 1887.

Common Sub-Divisions of Animal Husbandry

Historically, animal husbandry is broken up into animal subdivisions, agriculturists tending to specialize on one or two types of animals. Below is a list and brief description of some of the major subdivisions:

  • Swineherd: A person who cares for hogs and pigs (older English term: swine).
  • Shepherd: Usually a person who cares for sheep. However, in previous years, it was common to have herds which were made up of both sheep and goats, in which case the term shepherd was still employed.
  • goatherd: Someone who cares primarily for goats.
  • cowherd/Cowboys: Refers to those who raise, milk, and slaughter cattle. In more modern times, the cowboys or vaqueros of North and South America ride horses and participate in cattle drives to watch over cows and bulls raised primarily for food.
  • Herder: a generic term for anyone who tends to a herd of animals not listed above, such as Camels, yaks, and in Latin America, llamas and alpacas.
  • Equestrian: A person who breeds and takes care of horses.
  • Breeders: Generic term for anyone who specializes in the breeding of agricultural animals. More often, breeders are trained in specialized techniques, such as artificial insemination and embryo transfer, and are therefore independent hires of the usual farm staff.

Ethical aspects of animal husbandry

Ethical husbandry. A wounded Norwegian reindeer is moved on a snowmobile sled. Courtesy altapulken.no.

There are contrasting views on the ethical aspects of breeding animals in captivity, with one debate being in relation to the merits of allowing animals to live in natural conditions reasonably close to those of their wild ancestors, compared to the view that considers natural pressures and stresses upon wild animals from disease, predation, and the like as vindication for captive breeding.

Some techniques of animal husbandry such as factory farming, tail docking, the Geier Hitch, and castration, have been attacked by animal welfare groups as inhumane, unsanitary, and counterproductive to the overall benefit of society.[7] Some of these practices also are criticized by farmers who use more traditional or organic practices. Genetic engineering is also controversial though it does not necessarily involve suffering. People who believe in animal rights generally oppose all forms of animal husbandry.[8]

Education

Animal husbandry and animal sciences are taught around the world in colleges and universities. Students of animal science sometimes go on to pursue degrees in veterinary medicine following graduation, or pursue master's degrees or doctorates in disciplines such as nutrition, genetics and breeding, or reproductive physiology. A strong demand for knowledge and experience in the science of breeding and raising animals in the world wide agricultural markets helps graduates of these programs find work in the veterinary and human pharmaceutical industries, the livestock and pet supply and feed industries, as well as in academia.

Notes

  1. "animal husbandry." The Columbia Electronic Encyclopedia, Sixth Edition. Columbia University Press., 2003. Answers.com 29 Sep. 2007.[1]
  2. (2005) World of Genetics "Animal Husbandry" Retrieved September 17, 2007
  3. (2005) World of Invention "Animal Breeding" Retrieved September 17, 2007
  4. "animal husbandry." The Veterinary Dictionary. Elsevier, 2007. Answers.com 29 Sep. 2007. [[2]]
  5. Diamond, Jared. "Guns, Germs and Steel: The Fates of Human Societies" (Norton, 1999) ISBN 0393317552
  6. The many facets of pollution Bologna University web site for Science Communication. Retrieved September 29, 2007.
  7. Guither, Harold D. "Animal Rights: History and Scope of a Radical Social Movement" (Southern Illinois University Press 1998) ISBN 0809321580
  8. (2007) PETA ["About PETA"] Retrieved September 19, 2007

References
ISBN links support NWE through referral fees

  • Diamond, Jared. 1999. Guns, Germs and Steel: The Fates of Human Societies. Norton. ISBN 0393317552
  • Guither, Harold D. 1998. Animal Rights: History and Scope of a Radical Social Movement. Southern Illinois University Press. ISBN 0809321580
  • Williamson, Grahame. 1999. An Introduction to Animal Husbandry in the Tropics. Blackwell Publishing. ISBN 0632041935

External links

All links Retrieved October 17, 2007.

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