Oestrous cycles in Bos taurus cattle
| Autor: | Mark A. Crowe, James F. Roche, Niamh Forde, Patrick Lonergan, Marijke E. Beltman, Michael G. Diskin |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
endocrine system
medicine.medical_specialty media_common.quotation_subject Estrous Cycle Biology Luteal phase Sexual Behavior Animal Endocrinology Ovarian Follicle Food Animals Anterior pituitary Corpus Luteum Pregnancy Internal medicine Luteolysis Follicular phase medicine Animals Ovarian follicle Ovulation media_common Estrous cycle General Medicine medicine.anatomical_structure Cattle Female Animal Science and Zoology Folliculogenesis |
| Zdroj: | Animal Reproduction Science. 124:163-169 |
| ISSN: | 0378-4320 |
| DOI: | 10.1016/j.anireprosci.2010.08.025 |
| Popis: | The oestrous cycle in cattle lasts for 18–24 days. It consists of a luteal phase (14–18 days) and a follicular phase (4–6 days). During the cycle there are generally two (dairy cows) or three (heifers and beef cows) waves of ovarian follicle growth. Each wave of follicle growth consists of a period of emergence of a cohort of follicles, selection of a dominant follicle and either atresia or ovulation of the dominant follicle. These waves of follicle growth, initially established during the early pre-pubertal period of development occur throughout the entire cycle, with only the dominant follicle (DF) of the final wave coinciding with the follicular phase that undergoes final maturation and ovulation. Ovarian functions (follicle growth, ovulation, luteinisation and luteolysis) are regulated by the endocrine hormones of the hypothalamus (gonadotrophin-releasing hormone), anterior pituitary (follicle-stimulating hormone and luteinising hormone), ovaries (progesterone, oestradiol and inhibins) and the uterus (prostaglandin F2α). In postpartum cows resumption of regular oestrous cycles (in addition to uterine involution) is fundamental for re-establishment of pregnancy. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect