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These studbooks contain all the basic knowledge of all the particular animals within the program including birth date, gender, location, and some known lineage. With this information analyses can be made to determine several factors such as survival and reproduction rates, number of founders of the population, and inbreeding coefficients. A species coordinator will then look at all this information and make decisions on how to breed their animal in such a way that would create the most advantageous offspring. The coordinator does not only look through the studbook of their own specific institution but also those of institutions around the nation and sometimes around the world. If two compatible animals are found at different zoos, there are a few ways of mating the animals This could be done by transporting one animal from one location to another, but unfortunately this places quite a bit of stress on the animal which could result in lower likelihoods of mating. This is still a popular way of breeding animals in European zoological organizations, but this means that two highly compatible animals may not be able to be mated simply due to the locations, distance and variety of travel. Another option employs artificial fertilization techniques such as shipping semen, however these animals can become stressed during the collection of the semen or in the process of artificially inseminating the female. Yet another problem with this technique is semen quality will be decreased while being made possible to ship it and extending the life of the sperm.

Another example is the cheetah. The cheetah is the least genetically variable felid species making it very difficult to within breeding programs to find pairs of animals that would increase genetic diversity when all cheetahs are basically genetically identical. It is also possible that human practices are causing even more of an inbreeding depression in the handling of the cats in zoos than exists within the wild populations. Link: https://en.wikipedia.org/wiki/Captive_breeding

FINAL PAPER STARTS HERE

Captive Breeding Genes and Problems

The purpose of zoological institutions is not to house of animals in beautiful habitats for people to come observe on a day off. Zoo and aquariums do this to educate the public on the lifestyle of the animal, how the animal is active in the wild, and reasons as to why the animal may be endangered or threatened; most animal institutions serving the public preach conservation. While the help of all people is necessary in bettering the lives of these animals, for some species there is only so much that can be done for the preservation of the species in this way due to biological problems. Since many species living in these conservations are dwindling in numbers in the wild, and even fewer find homes in zoos, the genes available to pass on the next generations are also ever decreasing. To combat this phenomenon zoological associations organize animals into breeding programs to help diversify genetics to increase likelihood of successful animals and the species chances of being able to evolve in an ever changing world.

One animal that gives such possible problems to those breeding programs is the cheetah. When studying the genome of cheetahs in captivity it was found that cheetahs are almost completely the same animal genetically. This worried scientists because too much inbreeding can lead to detrimental recessive traits being introduced to the population and possibly continuing to evolve in a harmful tract. Inbreeding depression can cause issues such as smaller size of surviving offspring within a litter like is displayed in grey wolves (Liberg et al. 2005). This is an example of a lethal mutation occurring within a population when it is founded by a very small number of individuals causing high inbreeding coefficients where it may normally be hidden within heterozygousity. However, not all results of inbreeding are lethal; some are just problematic or reduce aesthetics (Trost 1982; Guillery and Kaas 1972). While in a zoo setting people may want to go see these non-lethal results of inbreeding whether it is for the oddly stunning look of a majestic beast (i.e. white tigers) or for the “freak show” nature of the mutation (i.e. The Blue People), if these mutations occurred in the wild they would almost certainly become lethal since an easily seen animal is quick prey and soon spotted as a predator. With all of these known and countless other examples available it is no wonder why those who are involved in the genetic future of animals wish to differentiate genes in order to reduce the chances of these occurrences.

The ultimate goal of most captive breeding programs is not only to stop the species from going extinct, but also to create a quantity of healthy animals that can then be reintroduced into the wild and can then survive on to propagate. This is accomplished mostly through the use of studbooks. These studbooks contain all the basic knowledge of all the particular animals within the program including birthdate, gender, location, and some known lineage. With this information analyses can be made to determine several factors such as survival and reproduction rates, number of founders of the population, and inbreeding coefficients (Smithsonian Conservation Biology Institute). A coordinator will then look at all this information and make decisions on how to breed their animal in such a way that would create the healthiest offspring. The coordinator does not only look through the studbook of their own specific institution but also those of institutions around the nation and sometimes around the world. It is due to advances in modern science and technology that this could even be thought possible to look into animals living at another zoo. This could be done by transporting the animal from one location to another in the hopes of mating taking place, but unfortunately this places quite a bit of stress on the animal. The animal does not understand what is going on and why they are suddenly being ripped from their home. These feelings often extend for a period of time resulting in lower likelihoods of mating. This is still a popular way of breeding animals in European zoological organizations (EAZA), but this means that two highly compatible animals may not be able to be mated simply due to the locations, distance and variety of travel. Nowadays in America if two animals are found by a coordinator to be compatible but not close by or neither zoo would be able to take in another adult at that time, it is possible to merely ship the semen of the male. Yet, stress on the animal is not eliminated this way, rather it is shifted; these animals can become stressed during the collection of the semen or in the process of artificially inseminating the female. It seems, though, that the stress is more limited in this way and it more economical which is why it is more often used in the United States. There are of course some draw backs to using technology to impregnate a female due to some biological and physiological effects of natural coupling that cannot be replicated within the confines of a laboratory procedure thus reducing prospect of fertilization and gestation happening. One species that gives many problems in this area is the Giant Panda.

Oddly it seemed that once giant pandas are in captivity they lost interest in mating or seemed to forget how to do it. This is a strange phenomenon that required deep study of the behavior of pandas. Another problem was trying to pinpoint the small window of time that the female pandas are in estrus when fertilization can work, because of these reasons scientists are forced to rely on artificial insemination (Pandas International). But even with all this effort, pregnancies are not always 100% effective. Pandas offer problems by way of behavior, while this can be incredibly problematic, especially before the reasons are understood, it can still be easier than trying to protect a species from a problem that is genetic.

Cheetahs are another source of stress for the species coordinators because almost every cheetah is genetically identical to one another making it very hard to find a mate that could increase the genetic diversity within the gene pool. This problem can be avoided in some animals by using mates from different populations, however, even in the wild cheetahs are all very similar. This is believed to be due to two separate genetic bottlenecks that the cheetahs underwent in Africa therefore followed by inbreeding due to the small number of founders (O’Brien et al. 1987). O’Brien et al. (1987) supposed this because while all cheetahs have low polymorphism and low heterozygosity, the East African cheetah subspecies is just slightly higher in these factors than the South African cheetah leading them to believe a major population bottleneck happened long ago and a smaller, more recent one happening in the South African subspecies. This could help in adding a little diversity by breeding across these subspecies, but overall the cheetah is still “the least genetically variable felid species” (O’Brien et al. 1987). Thankfully, this does not cause discouragement within breeding programs. Since cheetahs were first introduced to North American zoos almost sixty years ago the number of facilities housing the cats has increased as well as the number of cheetahs overall. More importantly through the biological and behavioral studies of the animals the number of captive born cheetahs has also been on the rise (Marker and O’Brien 1987). Zoos have the ability to track through stud information which lines carry the risks of specific diseases or certain health problem and can readily combat some of these problems to help them overcome. Another bonus of the cheetah is that through all these possible problems the species has continued on after the bottlenecking leading some like Michele (1994) to believe that cheetahs just naturally have low polymorphism in alleles and express dominant homozygosity. Since it might be perfectly natural, the species may have just evolved into its best possible constitution for the environment in which it lives. The problem that arises then is how the species would do if a dramatic change in environment were to occur? The cheetah could not have anything within its genes that would allow the species to be selected in the new surroundings and if this happened the species could easily die out. Although, if this truly is a naturally occurring narrowing of the gene pool should humans try to save the species by increasing genetic diversity or simply let nature take its course? On the other hand, it is also possible that human practices are causing even more of an inbreeding depression in the handling of the cats in zoos than exists within the wild populations (Michele 1994). Since it is easier to get information on captive animals, the numbers might be slightly skewed. It is doubtful that the difference would be so great that it would mean that there is not still an issue in the genetics of the wild animals. If this is recognized as true and human practices regarding the cheetah are changed to influence these findings than inbreeding may reduce slightly. It should also be taken into thought what a sudden mutation might do to a population. In most normal polymorphic populations a single mutation can be easily covered up due to selection, but in a situation like the cheetah it may present right away due to the low genetic diversity. This could be beneficial, if it is not a deleterious mutation, because the added genetic material would be able to be seen and therefore possibly utilized quickly.

Life, no matter how much it is researched and understood, will always be something that is special, somewhat magical and something that deserves to be treasured. Zoologists, species coordinators and everyone involved in the preservation of species hopes that the practices of captive breeding programs can help animals that have become endangered and hope that these species can continue on and have a place on this planet. Science, research, and technology improve every day to move toward achieving this goal. Species survival programs are just the beginning. Conservation efforts are also being prescribed by zoological institutions in an effort to stop further species from becoming threatened and optimistically creating or recreating wild natural environment so that animals may be reintroduced into the wild to negate the negative human impact.

REFERENCES

Captive Breeding Program. Pandas International. 

EAZA. EEPs and ESBs. European Association of Zoos and Aquaria. 

Guillery R. W., Kaas J. H. 1973. Genetic Abnormality of the Visual Pathways in a "White" Tiger. Science 180:1287-89.

Kenneth B., Kelly M. 2010. Cheetah Conservation in South Africa. Africa Insight 39:212-24.

Liberg O. et al. 2005. Severe Inbreeding Depression in a Wild Wolf (Canis lupus) Population. Biol. Lett. 1:17-20.

Marker L., O’Brien S. J. 1989. Captive Breeding of the Cheetah (Acinonyx jubatus) in North American Zoos (1871-1986). Zoo. Biol. 8:3-16.

Marker-Kraus L., Kraus D. 1997. Conservation Strategies for the Long-term Survival of the Cheetah Acinonyx Jubatus by the Cheetah Conservation Fund, Windhoek. International Zoo Yearbook 35:59-66.

Michele M. 1994. A Reassessment of Homozygosity and the Case for Inbreeding Depression in the Cheetah, Acinonyx jubatus: Implications for Conservation. Convser. Biol. 8:961-971.

O’Brien S. J. 1987. East African Cheetahs: Evidence for Two Population Bottlenecks? Proceedings of the National Academy of Sciences of the United States of America. 84:508-11.

Smithsonian Conservation Biology Institute. Captive Breeding. Smithsonian National Zoological Park. < http://nationalzoo.si.edu/scbi/endangeredspecies/capbreedpops/default.cfm>

Trost, C. 1982. The Blue People of Troublesome Creek. Science.

FINAL PAPER ENDS HERE

URL: https://en.wikipedia.org/wiki/Captive_breeding

Suggestions:
 * I noticed that when discussing success it is noted that "failure in other breeding habitats may be due to "poor" sperm morphology." I do not have access to the article from which this is referenced, but I have seen other articles which state that cheetahs have poor sperm quality themselves.
 * Included information about studbooks and how they are used by those in conservation could be useful to the reader, even possibly a link to another Wikipedia page.
 * Add details on how the breeding programs are implemented and cultural differences, for example in Europe natural mating is used more often. while in the US, artificial means are used in order to have more control over which genes will combine.

Langhorst.7` (talk) 05:42, 1 October 2014 (UTC)

Sentence: It is important to note, however, that some animals such as the cheetah have undergone genetic drift in the form of bottlenecks in the wild thousands of years ago, yet seem to experience little detrimental effects of inbreeding.

Topic: Lack of genetic diversity within the cheetah population and the possible causes and effects, and problems that are found in captive breeding programs due to it.

Annotated Bibliography: Marker, L. and O'Brien, S. J. (1989), Captive breeding of the cheetah (Acinonyx jubatus) in North American zoos (1871–1986). Zoo Biol., 8: 3–16. doi: 10.1002/zoo.1430080103 The article begins with a brief overview of the cheetah as a species and then an introduction into the breeding programs of North America related to the cheetah. It then explains the success of the captive breeding problems through percentages of births in captivity and the percentages of survivorship. There are also frequent references to the National Studbook with a table depicting the Studbook number and the problems relating to them. Pleasantly included is information comparing the breeding programs of North America and others.

Kenneth, B., and M. Kelly. "Cheetah Conservation in South Africa." Africa Insight 39.4 (2010): 212-24. Web. 14 Sept. 2014. . There is an explanation of historical and current distributions of cheetahs in South Africa with the influences of threats to the population and solutions to those threats.

Marker-Kraus, L., and D. Kraus. "Conservation Strategies for the Long-term Survival of the Cheetah Acinonyx Jubatus by the Cheetah Conservation Fund, Windhoek." International Zoo Yearbook 35.1 (1997): 59-66. Web. 14 Sept. 2014. . It starts with a background of cheetahs and the activities of conservation surrounding the species including research of all sorts involving the conservation of the animal. Additionally there is a focus of learning why cheetahs have succeeded where they have. Michele, M. “A Reassessment of Homozygosity and the Case for Inbreeding Depression in the Cheetah, Acinonyx jubatus: Implications for Conservation” Conservation Biology 8.4 (1994): 961-971 . This article dictates the importance of genetic diversity within the population and displays the lack of diversity in cheetahs due to inbreeding and a genetic bottleneck. It states that even with a bottlenecking event that genetic diversity would not be as narrow as it is, most likely due to recessive alleles; another problem with the bottleneck is that it should in theory not affect all subspecies based on temporal information of the event. The article proposes that cheetahs just naturally have low polymorphism with relative dominant homozygous gene pool. The article also discusses the apparent inbreeding depression seen in captive bred cheetahs but sees the problems as “more managerial than biological”. They additionally suppose that the wild cheetah population is only declining due to human interactions and not a fault of lack of genetic diversity.

O'Brien, S. J. "East African Cheetahs: Evidence for Two Population Bottlenecks?" Proceedings of the National Academy of Sciences of the United States of America 84 (1987): 508-11. Web. 14 Sept. 2014. . Through studies of the sperm quality of both the East African and South African varieties of cheetah and comparing the two, the researchers were able to come up with data supporting the idea of a second population bottleneck afflicting the cheetah.