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Registro Completo |
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
25/09/2000 |
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Data da última atualização: |
11/08/2023 |
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Autoria: |
GIBBONS, J. R.; KOT, K.; THOMAS, D. L.; WILTBANK, M. C.; GINTHER, O. J. |
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Título: |
Follicular and FSH dynamics in ewes with a history of high and low ovulation rates. |
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Ano de publicação: |
1999 |
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Fonte/Imprenta: |
Theriogenology, v. 52, n. 6, p. 1005-1020, Oct. 1999. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: Daily transrectal ultrasound scanning and twice-daily blood sampling were used to monitor the temporal relationships between FSH concentrations and follicle development during complete interovulatory intervals for ewes in which the ovulation rate in each of the 2 previous years was high or low (?3 and ?2 ovulations, respectively). Follicles that reached ?5 mm were used to define a follicular wave and were tracked retrospectively to 3 mm (emergence). The hypothesis that FSH surges (identified with a computer program) and follicular waves (retrospectively determined based on ultrasound scanning) are temporally associated was supported in both groups by the emergence of an anovulatory or ovulatory follicular wave near the peak of an FSH surge. Further support for the hypothesis was a significant increase in FSH concentrations before and a significant decrease after follicular-wave emergence in both groups independent of the identification of FSH surges. Ewes with a history of high ovulation rates had smaller follicles (anovulatory and ovulatory) and more ovulations, but the 2 groups were similar in the number of ovulatory follicular waves and associated FSH surges, number and characteristics of the FSH surges, and mean FSH concentrations per interovulatory interval. Surges of FSH were periodic (every 3 or 4 d) regardless of the ovulation-rate group or follicle response. In ewes with a low ovulation rate, the nonovulatory FSH surges were most frequently associated with emergence of detected anovulatory follicular waves. In ewes with a high ovulation rate, more FSH surges were not associated with a detected follicular wave, as defined, presumably because the largest follicle did not reach 5 mm. The results indicated that the factors resulting in a high ovulation rate were not exerted through circulatory patterns or concentrations of FSH but involved a shorter growth phase and smaller maximal diameter of follicles. MenosAbstract: Daily transrectal ultrasound scanning and twice-daily blood sampling were used to monitor the temporal relationships between FSH concentrations and follicle development during complete interovulatory intervals for ewes in which the ovulation rate in each of the 2 previous years was high or low (?3 and ?2 ovulations, respectively). Follicles that reached ?5 mm were used to define a follicular wave and were tracked retrospectively to 3 mm (emergence). The hypothesis that FSH surges (identified with a computer program) and follicular waves (retrospectively determined based on ultrasound scanning) are temporally associated was supported in both groups by the emergence of an anovulatory or ovulatory follicular wave near the peak of an FSH surge. Further support for the hypothesis was a significant increase in FSH concentrations before and a significant decrease after follicular-wave emergence in both groups independent of the identification of FSH surges. Ewes with a history of high ovulation rates had smaller follicles (anovulatory and ovulatory) and more ovulations, but the 2 groups were similar in the number of ovulatory follicular waves and associated FSH surges, number and characteristics of the FSH surges, and mean FSH concentrations per interovulatory interval. Surges of FSH were periodic (every 3 or 4 d) regardless of the ovulation-rate group or follicle response. In ewes with a low ovulation rate, the nonovulatory FSH surges were most frequently associated with... Mostrar Tudo |
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Palavras-Chave: |
Dinamica folicular; FSH; LH; Ovary; Taxa de ovulacao. |
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Thesagro: |
Ovino. |
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Thesaurus Nal: |
Anovulation; Females; Follicle-stimulating hormone; Ovulation; Physiology; Reproduction; Seasons; Sheep; Ultrasonography. |
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Categoria do assunto: |
L Ciência Animal e Produtos de Origem Animal |
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Marc: |
LEADER 02861naa a2200349 a 4500
001 1524150
005 2023-08-11
008 1999 bl uuuu u00u1 u #d
100 1 $aGIBBONS, J. R.
245 $aFollicular and FSH dynamics in ewes with a history of high and low ovulation rates.$h[electronic resource]
260 $c1999
520 $aAbstract: Daily transrectal ultrasound scanning and twice-daily blood sampling were used to monitor the temporal relationships between FSH concentrations and follicle development during complete interovulatory intervals for ewes in which the ovulation rate in each of the 2 previous years was high or low (?3 and ?2 ovulations, respectively). Follicles that reached ?5 mm were used to define a follicular wave and were tracked retrospectively to 3 mm (emergence). The hypothesis that FSH surges (identified with a computer program) and follicular waves (retrospectively determined based on ultrasound scanning) are temporally associated was supported in both groups by the emergence of an anovulatory or ovulatory follicular wave near the peak of an FSH surge. Further support for the hypothesis was a significant increase in FSH concentrations before and a significant decrease after follicular-wave emergence in both groups independent of the identification of FSH surges. Ewes with a history of high ovulation rates had smaller follicles (anovulatory and ovulatory) and more ovulations, but the 2 groups were similar in the number of ovulatory follicular waves and associated FSH surges, number and characteristics of the FSH surges, and mean FSH concentrations per interovulatory interval. Surges of FSH were periodic (every 3 or 4 d) regardless of the ovulation-rate group or follicle response. In ewes with a low ovulation rate, the nonovulatory FSH surges were most frequently associated with emergence of detected anovulatory follicular waves. In ewes with a high ovulation rate, more FSH surges were not associated with a detected follicular wave, as defined, presumably because the largest follicle did not reach 5 mm. The results indicated that the factors resulting in a high ovulation rate were not exerted through circulatory patterns or concentrations of FSH but involved a shorter growth phase and smaller maximal diameter of follicles.
650 $aAnovulation
650 $aFemales
650 $aFollicle-stimulating hormone
650 $aOvulation
650 $aPhysiology
650 $aReproduction
650 $aSeasons
650 $aSheep
650 $aUltrasonography
650 $aOvino
653 $aDinamica folicular
653 $aFSH
653 $aLH
653 $aOvary
653 $aTaxa de ovulacao
700 1 $aKOT, K.
700 1 $aTHOMAS, D. L.
700 1 $aWILTBANK, M. C.
700 1 $aGINTHER, O. J.
773 $tTheriogenology$gv. 52, n. 6, p. 1005-1020, Oct. 1999.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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