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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2
|
| pubmed:dateCreated |
1979-2-26
|
| pubmed:abstractText |
Milk samples were collected twice weekly from 535 dairy cows between parturition and the re-establishment of pregnancy to monitor ovarian activity by measurement of milk progesterone levels by radioimmunoassay. The mean progesterone levels after fertile and non-fertile first inseminations were similar from 21 days before until 13 days after insemination, those in non-pregnant animals declined while those in pregnant animals continued to rise until Day 22. Progesterone profiles of 47 repeat breeder cows (i.e. receiving greater than 3 inseminations) demonstrated that a variety of patterns was associated with the poor conception rate. A study of the post-partum interval showed that cows resumed cycles by 24 +/- 0.6 days after calving; the length of this interval varied significantly with the season of calving and non-significantly with the lactation number (i.e. age) of the cow, but was not related to yield. Of the 535 cows studied, 5.2% had not started to cycle within 50 days of calving and a further 5.2% resumed cycles which subsequently ceased. The progesterone profiles of acyclic cows indicated that after treatment with 0.5 mg LH-RH or a progesterone-releasing intravaginal device (PRID) for 14 days 75% of animals apparently ovulated but the calving to conception interval was not significantly altered compared with that of untreated control cows.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Nov
|
| pubmed:issn |
0022-4251
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
54
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
447-58
|
| pubmed:dateRevised |
2003-11-14
|
| pubmed:meshHeading |
pubmed-meshheading:722692-Age Factors,
pubmed-meshheading:722692-Anestrus,
pubmed-meshheading:722692-Animals,
pubmed-meshheading:722692-Breeding,
pubmed-meshheading:722692-Cattle,
pubmed-meshheading:722692-Female,
pubmed-meshheading:722692-Fertility,
pubmed-meshheading:722692-Fertilization,
pubmed-meshheading:722692-Lactation,
pubmed-meshheading:722692-Milk,
pubmed-meshheading:722692-Pregnancy,
pubmed-meshheading:722692-Progesterone,
pubmed-meshheading:722692-Seasons
|
| pubmed:year |
1978
|
| pubmed:articleTitle |
Milk progesterone levels in relation to conception, repeat breeding and factors influencing acyclicity in dairy cows.
|
| pubmed:publicationType |
Journal Article
|