estrus cycle


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Related to estrus cycle: anestrous

estrus cycle

Etymology: Gk, oistros, gadfly, kyklos, circle
the periodic changes in the female body that occur under the influence of sex hormones.

estrus cycle

The sequence from the beginning of one estrus period to the beginning of the next. It includes proestrus, estrus, and metestrus, followed by a short period of quiescence called diestrus.
See also: cycle

cycle

a succession or recurring series of events.

cardiac cycle
a complete cardiac movement, or heartbeat, including systole, diastole, and the intervening pause.
The cycle includes eight separate phases: (1) isovolumetric contraction; (2) maximum ejection; (3) reduced ejection; (4) protodiastole (onset of ventricular relaxation); (5) isovolumetric relaxation; (6) rapid flow; (7) diastasis (onset of atrial contraction); (8) atrial systole.
cell cycle
the cycle of biochemical and morphological events occurring in a dividing cell population; it consists of the S phase, occurring toward the end of interphase, in which DNA is synthesized; the G2 phase, for gap 2, the interval between S and M; the M phase, for mitosis, consisting of the four phases of mitosis; and the G1 phase, which lasts from the end of M until the start of S phase of the next cycle. Fully differentiated cells are nondividing and are said to be in G0.
Enlarge picture
Cell cycle. By permission from Booth DM, Small Animal Clinical Pharmacology and Therapeutics, Saunders, 2000
citric acid cycle
estrus cycle
see estrous cycle.
Krebs cycle
ovarian cycle
the sequence of physiological changes in the ovary involved in ovulation. See also ovulation and reproduction.
reproductive cycle
the cycle of physiological changes in the reproductive organs, from the time of fertilization of the ovum through gestation and parturition. See also reproduction.
sex cycle, sexual cycle
1. the physiological changes recurring regularly in the reproductive organs of female mammals when pregnancy does not supervene.
2. the period of sexual reproduction in an organism that also reproduces asexually.
tricarboxylic acid cycle
urea cycle
a cyclic series of reactions that produce urea, a major route for removal of the ammonia produced in the metabolism of amino acids in the liver and kidney. See also urea.
References in periodicals archive ?
In their search for sires to use in boosting twinning rates, the scientists consider ovulation rate, determined by rectal palpation, on seven daughters of each young sire for seven estrus cycles.
It seems likely that estradiol from non-gonadal sources might play a role in regulation of the hypothalamic-pituitary axis, reproductive system and estrus cycle of goats, as previously demonstrated in sheep (Martin, 1983; Adams, et al.
Rats exhibiting a minimum of two normal length (4-5 days) estrus cycles were killed with [CO.
By synchronizing the estrus cycles of an entire herd, commercial ranchers can pick the ideal time of the year for the calving season.
Over most of the species' range, does begin to cycle through as many as seven annual estrus cycles in September.
If you end the estrus cycles of female rats, those rats live significantly longer.
When the sex ratio is female biased, the mating period may extend over 2 - 3 estrus cycles and the calving period is delayed.
When more does start hitting their first estrus cycles, it's time to modify hunting strategies and setups once again to meet the new behavioral and activity changes.