Show simple item record

dc.contributor.advisorWelsh, Thomas H., Jr.
dc.creatorBryan, Tina Michelle
dc.date.accessioned2006-04-12T16:05:14Z
dc.date.available2006-04-12T16:05:14Z
dc.date.created2004-12
dc.date.issued2006-04-12
dc.identifier.urihttp://hdl.handle.net/1969.1/3253
dc.description.abstractThe chromosomal location of endocrine genes was established, and relationships between expression of specific endocrine genes and measures of testis function in normal and poor semen quality stallions was assessed. Consensus primer sequences for glucocorticoid receptor (GR) and luteinizing hormone receptor (LHR) were used to screen the CHORI-241 equine bacterial artificial chromosome (BAC) library. The identity of PCR-positive BAC clones was confirmed by sequencing. Verified BACs were mapped to horse metaphase chromosome spreads by fluorescence in situ hybridization (FISH). The BACs containing the GR and LHR were localized by FISH to ECA 14q16-q21 and ECA15q22-q23, respectively. In addition to FISH mapping, the 5000rad horse x hamster radiation hybrid (RH) panel was screened in duplicate. Two-point linkage analysis placed GR 0 cR from LEX047, while LHR was 36.67 cR from TKY011 on ECA14 and ECA15, respectively. Total testicular parenchymal weight, mean daily sperm production (DSP) per gram parenchyma and mean apoptotic rate (406.05 ± 24.33g vs. 180.01 ± 34.41g, 15.29 ± 0.87 vs. 10.24 ± 1.10, 6.70 ± 0.88 vs. 14.25 ± 1.11, respectively) differed (P<0.05) between normal (n=8) and poor semen quality (n=5) stallions. Also, plasma estradiol and inhibin concentrations were higher (P<0.05) in normal stallions than in poor semen quality stallions. Testicular expression of estrogen receptor beta (ER beta), &#946;B inhibin, prolactin receptor (PRLR), growth hormone receptor (GHR) and insulin-like growth factor I receptor (IGF-IR) mRNAs were all lower (P<0.05) in poor semen quality stallions than in normal stallions. The BACs and primers developed in this study will facilitate future investigations of GR and LHR gene structure in the horse as well as providing a resource for physiological investigation of these two genes that are primary regulators of stress responsiveness and fertility. These data add important endocrine genes to the horse cytogenetic map. Also, important hormonal and gene expression changes have been identified in poor semen quality stallions for further investigation.en
dc.format.extent1806156 bytesen
dc.format.mediumelectronicen
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherTexas A&M University
dc.subjectstallionen
dc.subjectgene expressionen
dc.subjectFISH mappingen
dc.titleTesticular function in normal and poor semen quality stallionsen
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentAnimal Scienceen
thesis.degree.disciplinePhysiology of Reproductionen
thesis.degree.grantorTexas A&M Universityen
thesis.degree.nameMaster of Scienceen
thesis.degree.levelMastersen
dc.contributor.committeeMemberIng, Nancy H.
dc.contributor.committeeMemberMcArthur, Newell H.
dc.contributor.committeeMemberRandel, Ronald D.
dc.contributor.committeeMemberBlanchard, Terry L.
dc.type.genreElectronic Thesisen
dc.type.materialtexten
dc.format.digitalOriginborn digitalen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record