estrus


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estrus

 [es´trus]
the recurrent, restricted period of sexual receptivity in female mammals other than human females, marked by intense sexual urge. See also estrous cycle. Called also estruation, estrum, and heat. adj., adj es´trual, es´trous.

es·trus

(es'trŭs),
That portion or phase of the sexual cycle of female animals characterized by willingness to permit coitus; readily detectable behavioral and other signs are exhibited by animals during this period.
Synonym(s): heat (3)
[G. oistros, mad desire]

estrus

also

oestrus

(ĕs′trəs)
n.
The periodic state of sexual excitement in the female of most mammals, excluding humans, that immediately precedes ovulation and during which the female is most receptive to mating; heat.

estrus

[es′trəs]
the cyclic period of sexual receptivity in mammals other than primates, marked by intense sexual urge and coinciding with the time that fertilization can take place.

es·trus

(es'trŭs)
That portion or phase of the sexual cycle of female animals characterized by willingness to permit coitus; readily detectable behavioral and other signs are exhibited by animals during this period.
Synonym(s): estruation, heat (2) , oestrus.
[G. oistros, mad desire]

estrus

the time during the reproductive cycle in animals when the female displays interest in mating and in most species will stand to be mounted by both sexes and mated by males. In most cases the animal is about to or has just ovulated, and is therefore pregnable, but some, including pregnant ones, may not be in true estrus.
At the time of estrus there are behavioral signs and changes in the external genitalia. In cows these include the passage of very clear mucus, swelling of the lips of the vulva and hoof brush marks on the side of the rump. Mares show frequent urination with squatting, elevation of the tail, swelling and winking of the vulva and rhythmic extrusion of the clitoris. Ewes are not demonstrative other than positioning themselves close to the rams or teasers. Goat does bleat a lot, rub themselves against fixed objects and hold their tail high, urinate frequently and evert the clitoris. Bitches wander away, stand with their tails held to one side and are attractive and receptive to males. Queens may be very demonstrative, especially Siamese. They rub against anything, crawl with their belly close to the floor, roll and vocalize with a deep, throaty growl.

estrus detection
in natural mating the male is, in most situations, the best possible detector. In artificial breeding or in hand mating the need to pick cows which are on heat is of paramount importance. Techniques available include the use of infertile teasers combined with heat mount detectors, tail paint, chin ball or siresine harnesses. In dairy herds it is usual to dispense with the teasers and depend on other cows to pick out and mount the cows that are in heat.
In sheep crayon or paint marking harnesses are used. In mares individual teasing with a pony or similar manageable male is used. In the other species detection is by simple visualization.
estrus expectancy chart
a wall chart for use at the dairy which points out those cows which are due to come into estrus during the next day or two and need to be observed closely.
false estrus
behavioral and external genital signs of estrus without ovulation occurring.
estrus induction
see estrus synchronization (below).
no visible estrus
abbreviated NVO (to accommodate the British spelling of oestrus) or NVE. Diagnosis indicating reproductive inefficiency; applied to cows which are not observed as being in estrus for a variable period, usually 50 days, after calving. Includes cows with anestrus due to various causes and failure of staff to observe or record estrus. A percentage of more than 10% of cows in a herd which have no visible estrus is an indication of a herd problem.
silent estrus
ovulation occurs, as detected by palpation or estrogen levels in the blood in the absence of behavioral signs.
estrus suppression
prevention of estral activity in companion animals without spaying them is practiced frequently. A variety of progestins are available and, at times, intravaginal and intrauterine devices have been used for this purpose. See also contraception.
estrus synchronization
aimed at having all of the animals in estrus, and later calving or lambing, at the same time. Prostaglandin injection is a common technique used to induce estrus in cows.
unexpressed estrus
see silent estrus (above).
References in periodicals archive ?
However, there are several factors that are responsible for slow reproductive efficiency with AI, such as poor estrus behaviour, difficulty in heat detection, poor semen quality and lack of skilled manpower (Anzar et al.
One female of November was considered as in early estrus since some cornified cells and nucleated cells were in similar proportions.
Treatment of post-partum cows and postpubertal heifers with synthetic progestin CIDR has been reported to induce estrus (Perry et al.
When it occurs without interruption and within a reasonable time it has positive effects on other reproductive indices such as earlier estrus and a higher pregnancy rate, among others.
Birth date most likely plays more of a role for does living below the Mason-Dixon Line, but health and age are also important for them and are the most common factors in precise estrus timing of does living roughly north of that line.
If you're committing to an all-day sit and you'd like the area around your stand to smell like a deer brothel, consider Buck Bomb's Doe in Estrus ($10), which now contains a full 6.
At the spot, I had made a mock scrape with my boot, baring the ground, and placing doe estrus in it along with a tarsal gland I had taken from another buck.
Regression procedure was carried out using MS Excel software to determine the relationship between body weight and estrus response.
Another factor that impacts the presence and distribution of estrus is the animal weight.
Artificial insemination should take place 12 to 24 hours after onset of estrus or standing heat.