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Registro Completo |
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
10/04/1996 |
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Data da última atualização: |
27/12/2013 |
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Autoria: |
JOHNSON, S. K.; DAILEY, R. A.; INSKEEP, E. K.; LEWIS, P. E. |
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Título: |
Effect of peripheral concentrations of progesterone on follicular growth and fertility in ewes. |
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Ano de publicação: |
1996 |
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Fonte/Imprenta: |
Domestic Animal Endocrinology, v. 13, n. 1, p. 69-79, 1996. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: The effects of progesterone (P4) on follicular growth and fertility in ewes were examined. In Experiment 1, 22 ewes received either one or three packets of P4 (5 g/packet) or an empty packet subcutaneously (sc) from Days 5 to 15 of the estrous cycle (estrus = Day 0). On Day 6, P4-treated ewes received 12.5 mg of prostaglandin F2 alpha. Follicles > or = 3 mm in diameter were observed via transrectal ultrasonography daily from Day 4 through estrus, corpora lutea (CL) were observed 5 to 7 d after estrus. Ewes with low (LOW; < or = 1 ng/ml; n = 5), intermediate (MED; >1 and <2 ng/ml; n = 10), or normal (NOR; > or =2 ng/ml; n = 7) P4 in jugular plasma on Days 7 through 15 differed in follicular development. The largest follicle at estrus was larger in ewes with LOW vs. MED and NOR P4 (7.8 +/- 0.3 vs. 6.9 +/- 0.2 mm; P < 0.05). Treatments differed in proportions of multiple-ovulating ewes, in which the oldest ovulatory follicle was first observed before Day 10 (LOW: 3 of 3, MED: 6 of 10, NOR: 0 of 5, respectively; P < 0.05). Estradiol was higher early in the treatment period in LOW ewes than in MED and NOR ewes (day x treatment; P < 0.05). In Experiment 2, ewes received 5 mg of P4 in corn oil (low progesterone [LP]; n = 51) or 2 ml of corn oil (CON; n = 49) sc every 12 hr on Days 6 through 14 of the estrous cycle before mating. LP ewes received 15 mg of prostaglandin F2 alpha on Day 6. Mean serum P4 on Days 7 through 15 was 0.6 +/- 0.1 ng/ml in LP and 1.9 +/- 0.1 ng/ml in CON ewes. Eleven LP and 12 CON ewes were scanned daily from Day 4 through mating, and in all ewes (n = 93), CL were counted 10 d after mating and embryos were counted at 25, 40, and 60 d of gestation. In multiple-ovulating ewes, day of cycle of appearance was earlier for the oldest (Day 6.1 +/- 0.8 vs. 10.4 +/- 0.8) but not second oldest (Day 11.7 +/- 1.0 vs. 12.2 +/- 0.9) ovulatory follicles in LP compared with CON ewes. The conception rate was lower in LP (72%) than in CON ewes (98%; P < 0.01). However, numbers of CL 10 d after mating, and in pregnant ewes, numbers of embryos 25 d after mating and lambs born, did not differ with treatment. In summary, low P4 increased the size of the largest follicles and the age of the oldest ovulatory follicles. Embryos resulting from the ovulation of older and younger follicles in the same ewe did not differ in their ability to survive. MenosAbstract: The effects of progesterone (P4) on follicular growth and fertility in ewes were examined. In Experiment 1, 22 ewes received either one or three packets of P4 (5 g/packet) or an empty packet subcutaneously (sc) from Days 5 to 15 of the estrous cycle (estrus = Day 0). On Day 6, P4-treated ewes received 12.5 mg of prostaglandin F2 alpha. Follicles > or = 3 mm in diameter were observed via transrectal ultrasonography daily from Day 4 through estrus, corpora lutea (CL) were observed 5 to 7 d after estrus. Ewes with low (LOW; < or = 1 ng/ml; n = 5), intermediate (MED; >1 and <2 ng/ml; n = 10), or normal (NOR; > or =2 ng/ml; n = 7) P4 in jugular plasma on Days 7 through 15 differed in follicular development. The largest follicle at estrus was larger in ewes with LOW vs. MED and NOR P4 (7.8 +/- 0.3 vs. 6.9 +/- 0.2 mm; P < 0.05). Treatments differed in proportions of multiple-ovulating ewes, in which the oldest ovulatory follicle was first observed before Day 10 (LOW: 3 of 3, MED: 6 of 10, NOR: 0 of 5, respectively; P < 0.05). Estradiol was higher early in the treatment period in LOW ewes than in MED and NOR ewes (day x treatment; P < 0.05). In Experiment 2, ewes received 5 mg of P4 in corn oil (low progesterone [LP]; n = 51) or 2 ml of corn oil (CON; n = 49) sc every 12 hr on Days 6 through 14 of the estrous cycle before mating. LP ewes received 15 mg of prostaglandin F2 alpha on Day 6. Mean serum P4 on Days 7 through 15 was 0.6 +/- 0.1 ng/ml in LP and 1.9 +/- 0.1 ng/ml i... Mostrar Tudo |
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Palavras-Chave: |
Concepcao; Rerpoducao. |
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Thesagro: |
Ciclo Estral; Ovino. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02979naa a2200205 a 4500
001 1516665
005 2013-12-27
008 1996 bl uuuu u00u1 u #d
100 1 $aJOHNSON, S. K.
245 $aEffect of peripheral concentrations of progesterone on follicular growth and fertility in ewes.
260 $c1996
520 $aAbstract: The effects of progesterone (P4) on follicular growth and fertility in ewes were examined. In Experiment 1, 22 ewes received either one or three packets of P4 (5 g/packet) or an empty packet subcutaneously (sc) from Days 5 to 15 of the estrous cycle (estrus = Day 0). On Day 6, P4-treated ewes received 12.5 mg of prostaglandin F2 alpha. Follicles > or = 3 mm in diameter were observed via transrectal ultrasonography daily from Day 4 through estrus, corpora lutea (CL) were observed 5 to 7 d after estrus. Ewes with low (LOW; < or = 1 ng/ml; n = 5), intermediate (MED; >1 and <2 ng/ml; n = 10), or normal (NOR; > or =2 ng/ml; n = 7) P4 in jugular plasma on Days 7 through 15 differed in follicular development. The largest follicle at estrus was larger in ewes with LOW vs. MED and NOR P4 (7.8 +/- 0.3 vs. 6.9 +/- 0.2 mm; P < 0.05). Treatments differed in proportions of multiple-ovulating ewes, in which the oldest ovulatory follicle was first observed before Day 10 (LOW: 3 of 3, MED: 6 of 10, NOR: 0 of 5, respectively; P < 0.05). Estradiol was higher early in the treatment period in LOW ewes than in MED and NOR ewes (day x treatment; P < 0.05). In Experiment 2, ewes received 5 mg of P4 in corn oil (low progesterone [LP]; n = 51) or 2 ml of corn oil (CON; n = 49) sc every 12 hr on Days 6 through 14 of the estrous cycle before mating. LP ewes received 15 mg of prostaglandin F2 alpha on Day 6. Mean serum P4 on Days 7 through 15 was 0.6 +/- 0.1 ng/ml in LP and 1.9 +/- 0.1 ng/ml in CON ewes. Eleven LP and 12 CON ewes were scanned daily from Day 4 through mating, and in all ewes (n = 93), CL were counted 10 d after mating and embryos were counted at 25, 40, and 60 d of gestation. In multiple-ovulating ewes, day of cycle of appearance was earlier for the oldest (Day 6.1 +/- 0.8 vs. 10.4 +/- 0.8) but not second oldest (Day 11.7 +/- 1.0 vs. 12.2 +/- 0.9) ovulatory follicles in LP compared with CON ewes. The conception rate was lower in LP (72%) than in CON ewes (98%; P < 0.01). However, numbers of CL 10 d after mating, and in pregnant ewes, numbers of embryos 25 d after mating and lambs born, did not differ with treatment. In summary, low P4 increased the size of the largest follicles and the age of the oldest ovulatory follicles. Embryos resulting from the ovulation of older and younger follicles in the same ewe did not differ in their ability to survive.
650 $aCiclo Estral
650 $aOvino
653 $aConcepcao
653 $aRerpoducao
700 1 $aDAILEY, R. A.
700 1 $aINSKEEP, E. K.
700 1 $aLEWIS, P. E.
773 $tDomestic Animal Endocrinology$gv. 13, n. 1, p. 69-79, 1996.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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