Preliminary investigations into the endocrine systems of subfertile cattle: location of a common lesion (rate-limiting step).
J Endocrinol
; 113(2): 167-71, 1987 May.
Article
en En
| MEDLINE
| ID: mdl-3295101
Dairy cows with a variety of clinical conditions were investigated in an attempt to identify the cause(s) of subfertility. Sequential or simultaneous injections of 20 micrograms gonadotrophin-releasing hormone (GnRH), 1 mg oestradiol benzoate and 0.06 mg ACTH(1-24) into five clinical cases of ovarian follicular cysts, two cases of poor body condition and one case of lameness and into control cows revealed a failure in the LH positive-feedback response to oestradiol in all eight clinical cases, but in only two out of twelve control cows. Two of the clinical cases and the two non-responding control cows had high or rising initial progesterone concentrations which would explain the absence of response. All cows studied responded similarly to GnRH and ACTH(1-24). It is suggested that hypothalamus-pituitary control of LH release may involve a rate-limiting step (in the oestradiol positive-feedback system) and that lesions at this point result in subfertility in a variety of clinical situations.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Enfermedades de los Bovinos
/
Infertilidad Femenina
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Endocrinol
Año:
1987
Tipo del documento:
Article
Pais de publicación:
Reino Unido