Christopher W. Tubbs
- Published in print:
- 2018
- Published Online:
- September 2018
- ISBN:
- 9780226538327
- eISBN:
- 9780226538631
- Item type:
- chapter
- Publisher:
- University of Chicago Press
- DOI:
- 10.7208/chicago/9780226538631.003.0023
- Subject:
- Biology, Biodiversity / Conservation Biology
The captive southern white rhinoceros (SWR) is not currently self-sustaining because of low fertility of captive-born females. The cause of this phenomenon is believed to be high dietary levels of ...
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The captive southern white rhinoceros (SWR) is not currently self-sustaining because of low fertility of captive-born females. The cause of this phenomenon is believed to be high dietary levels of phytoestrogens; endocrine disrupting chemicals (EDCs) produced by plants that can mimic the reproductive hormone estrogen. Typically, investigating the effects of EDCs on reproduction utilizes invasive methods, such as treatment of animals with potentially harmful chemicals. However, such approaches are not feasible for a species like the SWR. In this chapter the application of novel research to study the molecular mechanisms by which phytoestrogens affect SWR reproduction is reviewed. In addition, recent evidence that changing from high to low phytoestrogen diets may improve SWR fertility is presented. Taken together, the information presented here demonstrates an emerging opportunity to apply laboratory-based research to the ex-situ conservation of threatened or endangered species.Less
The captive southern white rhinoceros (SWR) is not currently self-sustaining because of low fertility of captive-born females. The cause of this phenomenon is believed to be high dietary levels of phytoestrogens; endocrine disrupting chemicals (EDCs) produced by plants that can mimic the reproductive hormone estrogen. Typically, investigating the effects of EDCs on reproduction utilizes invasive methods, such as treatment of animals with potentially harmful chemicals. However, such approaches are not feasible for a species like the SWR. In this chapter the application of novel research to study the molecular mechanisms by which phytoestrogens affect SWR reproduction is reviewed. In addition, recent evidence that changing from high to low phytoestrogen diets may improve SWR fertility is presented. Taken together, the information presented here demonstrates an emerging opportunity to apply laboratory-based research to the ex-situ conservation of threatened or endangered species.
Barbara Demeneix
- Published in print:
- 2014
- Published Online:
- August 2014
- ISBN:
- 9780199917518
- eISBN:
- 9780190232382
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199917518.001.0001
- Subject:
- Psychology, Behavioural Neuroendocrinology
There is a global acceleration in the incidence of neurodevelopmental disorders. Numbers of children affected by an autism spectrum disorders (ASD) in the United States has reached 1 in 88 (1 in 56 ...
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There is a global acceleration in the incidence of neurodevelopmental disorders. Numbers of children affected by an autism spectrum disorders (ASD) in the United States has reached 1 in 88 (1 in 56 boys), and even more have attention-deficit/hyperactivity disorder (ADHD). The cost of these disorders to the individual and society is enormous: ASD alone costs the United States a staggering 130 billion US dollars annually. Genetic causes cannot account for these increases. Surges in incidence must implicate environmental factors. Environmental chemicals interfering with thyroid hormone signaling are potential culprits. This argument is substantiated by four facts. First, thyroid hormone is essential for brain growth; second, lack of thyroid hormone causes intellectual deficiency; third, many chemicals found in the environment have thyroid hormone–disrupting properties; and finally, many women enter pregnancy with insufficient iodine. Chemical pollution and iodine deficiency can also decrease the overall IQ of the population. Just a 5% decrease in overall IQ can have serious socioeconomic consequences, decreasing the numbers of gifted people and increasing those with IQs below 70. The author provides an historical overview of cases documenting environmental pollution causing IQ losses across populations, explains the physiology of thyroid hormone action, the importance of iodine and selenium for thyroid hormone signaling and brain development, why thyroid hormone is such a sensitive target of environmental pollution, and the role of gene × environment interactions in neurodevelopmental disorders. What can and is to be done by individuals, associations, and decision makers to staunch these epidemics is also detailed.Less
There is a global acceleration in the incidence of neurodevelopmental disorders. Numbers of children affected by an autism spectrum disorders (ASD) in the United States has reached 1 in 88 (1 in 56 boys), and even more have attention-deficit/hyperactivity disorder (ADHD). The cost of these disorders to the individual and society is enormous: ASD alone costs the United States a staggering 130 billion US dollars annually. Genetic causes cannot account for these increases. Surges in incidence must implicate environmental factors. Environmental chemicals interfering with thyroid hormone signaling are potential culprits. This argument is substantiated by four facts. First, thyroid hormone is essential for brain growth; second, lack of thyroid hormone causes intellectual deficiency; third, many chemicals found in the environment have thyroid hormone–disrupting properties; and finally, many women enter pregnancy with insufficient iodine. Chemical pollution and iodine deficiency can also decrease the overall IQ of the population. Just a 5% decrease in overall IQ can have serious socioeconomic consequences, decreasing the numbers of gifted people and increasing those with IQs below 70. The author provides an historical overview of cases documenting environmental pollution causing IQ losses across populations, explains the physiology of thyroid hormone action, the importance of iodine and selenium for thyroid hormone signaling and brain development, why thyroid hormone is such a sensitive target of environmental pollution, and the role of gene × environment interactions in neurodevelopmental disorders. What can and is to be done by individuals, associations, and decision makers to staunch these epidemics is also detailed.
