Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1999-9-2
pubmed:abstractText
Crossbred Brahman heifers (n = 60) were studied to determine the effect of a 7-d intravaginal progesterone-releasing insert (INSERT) in combination with PG (Lutalyse; 25 mg i.m.) and estradiol benzoate (EB; .5 mg i.m.) on time of ovulation and estrous behavior. In Phase I, heifers at unknown stages of the estrous cycle were assigned by BW and body condition score to one of the three treatments on d 0: 1) INSERT for 7 d and PG on d 7 (CONTROL; n = 10); 2) INSERT for 7 d, PG on d 7, and EB 24 h after INSERT removal (EB24; n = 10); or 3) INSERT for 7 d, PG on d 7, and EB 48 h after INSERT removal (EB48; n = 10). Blood samples were collected every 8 h after INSERT removal. Also, blood sampling and ultrasonography began 8 h after the onset of estrus, determined with HeatWatch devices, and every 4 h thereafter to detect ovulation. In Phase II, Phase-I treatments (n = 10/treatments) were replicated, but only behavioral estrus data were collected to minimize handling of heifers. Frequent handling of heifers did not influence (P > .1) the interval from INSERT removal to the onset of HeatWatch and visual estrus and duration of estrus, so behavioral estrus data were combined for Phases I and II. Interval from INSERT removal to HeatWatch estrus was decreased (P < .05) in EB24 (45.5 h) vs EB48 (55.9 h) and CONTROL (59.2 h). Interval from INSERT removal to ovulation differed (P < .04) between CONTROL, EB24, and EB48 (93.5, 74.5, and 78.9 h, respectively). Ovulatory follicle size was similar (P > .1) between CONTROL, EB24, and EB48 (14.4, 12.5, and 14.1 mm, respectively). Duration of estrus was similar for CONTROL, EB24, and EB48 (14.0, 15.1, and 17.6 h, respectively). No difference (P > . 1) was observed in number of mounts received between CONTROL, EB24, and EB48 (28.0, 25.7, and 39.4, respectively), but number of mounts received increased in Phase II vs Phase I (40.0 and 22.2, respectively; P < .05). In conclusion, EB hastened the interval from INSERT removal to ovulation without altering duration of estrus or number of mounts received. Frequent handling of heifers did not affect interval to first mount received after INSERT removal or duration of estrus, but it decreased the total number of mounts received.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-8812
pubmed:author
pubmed:issnType
Print
pubmed:volume
77
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1860-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Ovulation and estrus characteristics in crossbred Brahman heifers treated with an intravaginal progesterone-releasing insert in combination with prostaglandin F2alpha and estradiol benzoate.
pubmed:affiliation
Department of Animal Sciences, University of Florida, Gainesville 32611-0910, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't