Linked Life Data

15990256

Source:http://linkedlifedata.com/resource/pubmed/id/15990256

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2006-1-31
pubmed:abstractText
The present study was conducted to assess effects of the gonadotropin-releasing hormone agonist (GnRHa) triptorelin in dairy heifers. The peptide was released from a commercial 4-week depot formulation (Decapeptyl Depot) administered at animals' estrus (day 0). First experiment (EXP I, n=5), which was aimed to explore the availability of peptide, detected a maximum of triptorelin concentration between day 2 and 5 after depot injection, and the peptide remained detectable by RIA in peripheral blood for about 3 weeks. In further experiments, the peptide release was terminated on day 9 (EXP II, n=16) or day 21 (EXP III, n=47). Treatment effects were studied on follicular development, the characteristics of cumulus-oocyte complexes (COCs) (EXP II; EXP IIIa) and secretions of LH and progesterone (EXP IIIb). Results showed that the occurrence of the pre-ovulatory LH surge was more uniform in treated heifers than that in controls. The duration of ovulation periods was similar amongst the heifers of EXP II, but more compact amongst those of EXP III each compared with the respective controls. Post-ovulatory, the number of LH pulses was significantly reduced by treatment, whereas both basal LH and progesterone concentrations were elevated on a few days. Follicular growth was reduced only by the prolonged influence of the GnRHa. There were increased proportions of both degenerated COCs and immature oocytes from small follicles (<3mm in diameter), and meiotic configuration and quality of oocytes isolated from follicles 3-5mm were changed after the prolonged, 21-day treatment. These results indicate that a continuous influence of a GnRHa over more than 1 week may increasingly impair the development of bovine follicles and oocytes. This may have some significance for the development of novel GnRH-based techniques in regulating the reproductive function in cattle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0378-4320
pubmed:author
pubmed:issnType
Print
pubmed:volume
92
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9-28
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Endocrine, morphological, and cytological effects of a depot GnRH agonist in bovine.
pubmed:affiliation
Unit of Reproductive Biology, Research Institute for the Biology of Farm Animals, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany. falk.schneider@fbn-dummerstorf.de
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't