Linked Life Data

8997875

Source:http://linkedlifedata.com/resource/pubmed/id/8997875

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-2-18
pubmed:abstractText
The effect of excess dietary urea on ovulation and early embryo development of sheep was studied. Thirty Border Leicester x Scottish Black face ewes randomly assigned to three treatments were given a basal control diet (C) which met energy requirements for body weight maintenance. Other treatments were basal diet plus 24 g of urea/day (low urea, L) or plus 48 g (high urea, H)/day. The reproductive cycles of the ewes were synchronized using a single injection of prostaglandin (PGF2 alpha) and progesterone by an intravaginal controlled internal drug release (CIDR) device for 12 days. Ovulation was induced by the use of pregnant mare serum gonadotrophin (PMSG). Ewes were inseminated approximately 52 hours after CIDR device removal using a laparoscopic technique. Embryos were recovered at Day 4 or Day 11 after insemination from half of the ewes from each treatment group. There were no significant differences in ovulation rates among the three groups. The embryo recovery rates were not affected by day of recovery. At embryo recovery on Day 4, 7/13 in C, 3/6 in L and 0/7 in H embryos were morulae. After 72 hours of in vitro culture 6/10 in C, 2/3 in L and 0/4 in H embryos developed to the blastocyst stage. Pregnancies sustained were C 6/8, L 5/7 and H 1/3 of the autotransfers. Throughout the experiment plasma urea levels were significantly affected by diet (p < 0.01). Plasma ammonia levels in the H group were significantly higher than those in the C and L groups (p < 0.05) for 4 hours after each feed. There was no treatment effect on plasma progesterone concentration. The luteinizing hormone (LH) surge onset time and amplitude were not correlated to ovulation rate and were not affected by treatment. It is concluded that high circulating concentrations of plasma urea and ammonia have an adverse effect on early embryo development. This effect was independent of any alterations in progesterone and LH concentrations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0047-1917
pubmed:author
pubmed:issnType
Print
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
139-51
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Excess dietary urea intake in ewes and its effect on ovulation rate and embryo development.
pubmed:affiliation
Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Japan.
pubmed:publicationType
Journal Article, In Vitro