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Title: MORPHOLOGICAL VARIABILITY IN GENETICALLY DEFINED CATEGORIES OF ANURAN HYBRIDS

Authors:
 [1];  [2]
  1. Savannah River Ecology Laboratory, Drawer E Aiken SC 29801
  2. Department of Genetics, University of Georgia, Athens GA 30602
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1401317
Grant/Contract Number:
AC09-76SROO-819
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Evolution
Additional Journal Information:
Journal Volume: 41; Journal Issue: 1; Related Information: CHORUS Timestamp: 2017-10-20 16:49:19; Journal ID: ISSN 0014-3820
Publisher:
Wiley-Blackwell
Country of Publication:
United States
Language:
English

Citation Formats

Lamb, Trip, and Avise, John C. MORPHOLOGICAL VARIABILITY IN GENETICALLY DEFINED CATEGORIES OF ANURAN HYBRIDS. United States: N. p., 2017. Web. doi:10.1111/j.1558-5646.1987.tb05778.x.
Lamb, Trip, & Avise, John C. MORPHOLOGICAL VARIABILITY IN GENETICALLY DEFINED CATEGORIES OF ANURAN HYBRIDS. United States. doi:10.1111/j.1558-5646.1987.tb05778.x.
Lamb, Trip, and Avise, John C. 2017. "MORPHOLOGICAL VARIABILITY IN GENETICALLY DEFINED CATEGORIES OF ANURAN HYBRIDS". United States. doi:10.1111/j.1558-5646.1987.tb05778.x.
@article{osti_1401317,
title = {MORPHOLOGICAL VARIABILITY IN GENETICALLY DEFINED CATEGORIES OF ANURAN HYBRIDS},
author = {Lamb, Trip and Avise, John C.},
abstractNote = {},
doi = {10.1111/j.1558-5646.1987.tb05778.x},
journal = {Evolution},
number = 1,
volume = 41,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on May 31, 2018
Publisher's Accepted Manuscript

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  • The present report focuses on novel animal models of male infertility: genetically defined mice bearing single-gene mutations that induce infertility. The primary goal of the investigations was to identify the reproductive defects in these mutant mice. The phenotypic effects of the gene mutations were deciphered by comparing the mutant mice to their normal siblings. Initially testicular steroidogenesis and spermatogenesis were investigated. The physiologic markers for testicular steroidogenesis were steroid secretion by testes perifused in vitro, seminal vesicle weight, and Leydig cell histology. Spermatogenesis was evaluated by the enumeration of homogenization-resistant sperm/spermatids in testes and by morphometric analyses of germ cellsmore » in the seminiferous epithelium. If testicular function appeared normal, the authors investigated the sexual behavior of the mice. The parameters of male sexual behavior that were quantified included mount patency, mount frequency, intromission latency, thrusts per intromission, ejaculation latency, and ejaculation duration. Females of pairs breeding under normal circumstances were monitored for the presence of vaginal plugs and pregnancies. The patency of the ejaculatory process was determined by quantifying sperm in the female reproductive tract after sexual behavior tests. Sperm function was studied by quantitatively determining sperm motility during videomicroscopic observation. Also, the ability of epididymal sperm to function within the uterine environment was analyzed by determining sperm capacity to initiate pregnancy after artificial insemination. Together, the experimental results permitted the grouping of the gene mutations into three general categories. They propose that the same biological markers used in the reported studies can be implemented in the assessment of the impact that environmental toxins may have on male reproduction.« less
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  • Interspecific hybrids between Parthenium argentatum, the guayule rubber plant, and P. fruticosum var. fruticosum were evaluated for their potential rubber content and quality. Fifteen-mo-old field-grown plants of P. fruticosum var. fruticosum measured four times more in height and spread than those of P. argentatum, but contained less than 0.05% rubber of low mol wt. Parthenium argentatum showed 2% rubber content, with a mol wt of about one million. Resin contents varied little among parents or hybrids. The same age F/sub 1/ hybrids were intermediate in height and spread and had low rubber content, but showed presence of high mol wtmore » rubber like the guayule parent. This indicates that high mol wt rubber is expressed over the low mol wt rubber in F/sub 1/ hybrids. Despite low rubber content but favorable biomass production, F/sub 1/ hybrids revealed irregular meiotic chromosome behavior and low pollen and seed germination. These results suggest that interspecific F/sub 1/ hybrids may be used in backcross programs to increase biomass and rubber content in guayule.« less
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