Data/hora: 16/06/2024 19:09:17

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 01/08/1992
Data da última atualização: | 03/08/2023
Autoria: | THOMAS, G. B.; OLDHAM, C. M.; HOSKINSON, R. M.; SCARAMUZZI, R. J.; MARTIN, G. B.
Título: | Effect of immunization against progesterone on oestrus, cycle lenght, ovulation rate, luteal regression and LH secretion in the ewe.
Ano de publicação: | 1987
Fonte/Imprenta: | Australian Journal of Biology Sciency, v. 40, n. 3, p. 307-313, 1987.
DOI: | https://doi.org/10.1071/BI9870307
Idioma: | Inglês
Conteúdo: | Abstract: The effects of active immunization against progesterone on reproductive activity were studied in Merino ewes. Immunization against progesterone caused a shortening (P < 0'01) of the interval between ovulations from 17-18 days (controls) to between 6 and 10 days (immunized group); this was associated with a corresponding reduction in the interval between LH surges. The immunized ewes also had higher (P < O· 05) ovulation rates (1' 72) than controls (I. 25) and exhibited a reduced (P < 0'01) incidence of oestrus (26% v. 95%). Many immunized ewes continued to ovulate despite the persistence of corpora lutea from earlier ovulations which led to an accumulation on the ovaries of many corpora lutea of different ages. The frequency of LH pulses in ewes immunized against progesterone (1'8 ± 0·2 pulses/4 h) was significantly (P < 0'001) higher than that of control ewes (0'3 ± 0·1 pulses/4 h). This study highlights the importance of progesterone in the control of oestrus, ovulation, ovulation rate, luteal regression and the secretion of LH in the ewe.
Thesagro: | Ciclo Estral; Fisiologia; Ovino; Reprodução.
Thesaurus Nal: | Endocrinology; Estrus; Immunization; Luteinizing hormone; Luteolysis; Ovulation; Physiology; Progesterone; Reproduction; Sheep.
Categoria do assunto: | L Ciência Animal e Produtos de Origem Animal
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (5815-1) - ADD - AP - DD -  -  -  - DIS