Receiving Helpdesk

estrous cycle in animals examples

by Luigi Hammes Published 4 years ago Updated 3 years ago

There are also a variety of different forms:

  • Polyestrous Animals - Estrous cycles throughout the year ( cattle, pigs, mice, rats ).
  • Seasonally Polyestrous Animals - Animals that have multiple estrous cycles only during certain periods of the year (horses, sheep, goats, deer, cats ).
  • Monestrous Animals - Animals that have one estrous cycle per year ( dogs, wolves, foxes, and bear)

Seasonally polyestrous animals are those that can go through a success of estrous cycles during a particular time of the year. For example, horses, sheep, goats, and the red deer (elk) go into estrus more than one time during a particular season if not mated.

Full Answer

What is an estrous cycle in animals?

Estrous cycles start after sexual maturity in females and are interrupted by anestrous phases, otherwise known as "rest" phases, or by pregnancies. Typically, estrous cycles repeat until death. These cycles are widely variable in duration and frequency depending on the species.

What animals do not have an oestrous cycle?

A few mammalian species, such as rabbits and cats, do not have an oestrous cycle, instead being induced to ovulate by the act of mating and are able to conceive at almost any arbitrary moment.

What are the four phases of the estrous cycle?

It is similar to the human reproductive cycle, commonly called the menstrual cycle (ovarian and uterine cycles). The estrous cycle has four phases, namely proestrus, estrus, metestrus and diestrus and lasts for 4 to 5 days [4] (Table ​(Table1).1).

What is an example of a estrus animal?

Cattle. Female cattle, also referred to as "heifers" in agriculture, will gradually enter standing estrus, or "standing heat," starting at puberty between 9 and 15 months of age. The cow estrous cycle typically lasts 21 days. Standing estrus is a visual cue which signifies sexual receptivity for mounting by male cattle ...

What is oestrus cycle give two examples?

The females of placental mammals exhibit cyclical changes in the activities of ovaries, accessory ducts and hormones during the reproductive phase. These cyclic changes are called oestrus cycle.It is sen in non-primates such as cows,sheep.

What is estrus cycle in animals?

The estrous cycle represents the cyclical pattern of ovarian activity that facilitates female animals to go from a period of reproductive receptivity to non-receptivity ultimately allowing the establishment of pregnancy following mating. The normal duration of an estrous cycle in cattle is 18–24 days.

Which animals are Polyestrous?

Animals that cycle continuously throughout the year, such as swine and cattle, are termed polyestrous.

What is estrous cycle in cattle?

The estrous cycle of the cow starts after puberty and occurs approximately every 21 days (17 to 24 days) except for pregnancy, reproductive disease or hormonal disorder. During estrous cycle, the reproductive tract is prepared for estrus or heat (the period of sexual receptivity) and ovulation (ovum release).

What is estrous cycle in rat?

The short length of the estrous cycle of rats makes them ideal for investigation of changes occurring during the reproductive cycle. The estrous cycle lasts four days and is characterized as: proestrus, estrus, metestrus and diestrus, which may be determined according to the cell types observed in the vaginal smear.

What type of estrous cycle do dogs have?

The canine estrous (reproductive) cycle is made up of 4 different stages. These are proestrus, estrus, diestrus, and anestrus. Each stage has differing signs related to behavior, physical or clinical changes, hormonal changes, physiologic changes, and cytologic (vaginal smear) changes.

Are dogs Polyestrous?

estrus period , dogs) are monestrous, having only one heat during a breeding season. Others (e.g., ground squirrels) are polyestrous: if not impregnated, they will come into heat repeatedly during the breeding season.

Are cats Polyestrous?

Seasonality. The cat is described as being seasonally polyestrous and a long-day breeder. Queens undergo estrous cycles repeatedly during a breeding season unless interrupted by pregnancy, pseudopregnancy, or illness. Estrous cycles will occur at variable intervals but most typically every 14 to 21 days.

What is Polyestrous give example?

Definition of polyestrous : having more than one period of estrus in a year.

What is Monoestrous give example?

Monoestrous animals are those in which only one estrous cycle can be seen in a year. For example, dogs, fox etc. Whereas, diestrous animals are those in which two estrous cycles are seen in a year. For example, horse, goats etc.

Are horses Polyestrous?

Horses (Equus caballus) belong to the group of seasonally polyestrous mammals. Estrous cycles typically start with increasing daylight length after winter, but mares can differ greatly in the timing of onset of regular estrus cycles.

What is the difference between estrus and estrous cycle? - Answers

What is the length of estrus in pigs? "four months, four days." Ok you are off just a little. First of all, you are thinking of the gestation period which is actually 3 months 3 weeks 3 days. the ...

What is the basic estrous cycle of the cow? – Beef Cattle

The basic estrous cycle of the cow averages 21 days in duration (a range of 18 to 24 days) and extends from one period of heat (estrus) to the next.

What is the basic estrous cycle of the cow? – DAIReXNET

The basic estrous cycle of the cow averages 21 days in duration (a range of 18 to 24 days) and extends from one period of heat (estrus) to the next.

Oestrus Cycle: Meaning, Phases and Difference with Menstrual Cycle

Difference Between Oestrus Cycle and Menstrual Cycle. The key difference between Menstrual and Oestrous Cycles is that Menstrual Flow occurs in primates such as monkeys, apes, and humans, in which an unfertilized ovum along with a ruptured uterine epithelium discharges about 50-100 ml of blood and some mucus through the vaginal orifice and is called menstrual flow, whereas the Oestrous Cycle ...

Estrous Cycle - an overview | ScienceDirect Topics

Mark A. Crowe, in Encyclopedia of Dairy Sciences (Third Edition), 2022 Introduction. The estrous cycle represents the cyclical pattern of ovarian activity that facilitates female animals to go from a period of reproductive receptivity to non-receptivity ultimately allowing the establishment of pregnancy following mating. The normal duration of an estrous cycle in cattle is 18–24 days.

The Female Rat Reproductive Cycle: A Practical Histological Guide to ...

Estrus was used first by Heape (1900) as a Latin adaptation of the Greek word oistros, meaning gadfly, sting, or frenzy to describe the “special period of sexual desire of the female” (Freeman 1994).He also used: anestrus, nonbreeding season when reproductive organs are quiescent; proestrus, animal coming on heat; metestrus, in the absence of conception, when estrus changes in the ...

What is the difference between "estrous" and "estrus"?

With only a one letter difference, the words “estrous” and “estrus” look and sound similar, but there’s an important difference. Estrus is a noun and refers to the short period in which a cow is sexually receptive and will stand to be bred. Estrus is commonly called “heat.”.

Why does my cow stop cycling?

Sometimes a medical problem, such as ovarian cysts or an infection of the reproductive tract, can cause a cow to stop cycling.

What does it mean when a cow is in heat?

The high estrogen level produced by the dominant ovarian follicle causes the heifer or cow to show signs of estrus. This means she’s sexually receptive—she’s said to be “in heat”—and will stand to be bred or mounted by other cows, commonly referred to as “standing heat.” The heifer or cow may show other signs of estrus, such as having a clear mucous vaginal discharge and an increased activity level. She may also vocalize more and try to mount other cows. Estrus is considered the beginning, or “Day 0,” of the estrous cycle.

Why won't the corpus luteum regress?

Using prostaglandin drugs in the first 5 days of the estrous cycle won’t cause the corpus luteum to regress because the early corpus luteum is immature and doesn’t respond to prostaglandin F2-alpha. Five prostaglandin products are FDA-approved for several therapeutic uses.

What is the follicular phase?

The Follicular Phase: Waves of Ovarian Follicles. The follicular phase of the estrous cycle refers to the narrow period of time right before estrus (heat) and ovulation (release of the egg for possible fertilization).

How many follicles are there in a cow?

A follicle is a structure containing an egg, also called an ovum, and other cells that can produce estrogen. A heifer or cow will generally have two or three groups of ovarian follicles—called waves—develop during a single estrous cycle (the range is one to four waves).

How long does a heifer cycle last?

After puberty, a heifer continues to have regular estrous cycles every 21 days (the normal range is every 18 to 24 days). The estrous cycle in cattle is complex and regulated by several hormones and organs (see Figure 1).

What is the estrous cycle?

The estrous cycle represents the cyclical pattern of ovarian activity that facilitates female animals to go from a period of reproductive receptivity to non-receptivity ultimately allowing the establishment of pregnancy following mating. The normal duration of an estrous cycle in cattle is 18–24 days. The cycle consists of two discrete phases: the luteal phase (14–18 days; met-estrus and di-estrus) and the follicular phase (4–6 days; pro-estrus and estrus). The luteal phase is the period following ovulation when the corpus luteum (CL) is formed, while the follicular phase is the period following the demise of the corpus luteum (luteolysis) until ovulation. During the follicular phase final maturation and ovulation of the ovulatory follicle occurs which leads to the release of an oocyte (the female gamete) into the oviduct allowing the potential for fertilization.

How long does an ewe's estrus cycle last?

Length of season. The estrous cycle of ewes lasts 17 days and 21 days for the doe. It is common to leave the males in a minimum of 34–42 days to ensure that each female has had two periods of estrus.

What is the difference between follicular and luteal phases?

The luteal phase is the period following ovulation when the corpus luteum (CL) is formed, while the follicular phase is the period following the demise of the corpus luteum (luteolysis) until ovulation.

What hormones regulate the estrous cycle in cattle?

The estrous cycle in cattle is regulated by the hormones of the hypothalamus (gonadotrophin-releasing hormone; GnRH), the anterior pituitary (follicle-stimulating hormone; FSH and luteinizing hormone; LH), the ovaries (progesterone; P4, estradiol; E2, and inhibins), and the uterus (prostaglandin F2α; PGF; Figure 1 ). These hormones function through a system of positive and negative feedback to govern the estrous cycle. GnRH is a decapeptide that was first isolated from the hypothalamus of pigs. Its control of the estrous cycle is mediated via its actions on the anterior pituitary which regulates the secretion of the gonadotrophs, LH, and FSH. The pulsatile secretion of basal levels of GnRH from the tonic center of the hypothalamus and the preovulatory surge of GnRH from the surge center of the hypothalamus prevent the desensitization of the GnRH receptor on the gonadotroph cells of the anterior pituitary. After transportation of GnRH from the hypothalamus to the pituitary gland via the hypophyseal portal blood system, GnRH binds to its G-protein-coupled receptor on the cell surface of the gonadotroph cells. This binding releases intracellular calcium which activates intermediaries in the mitogen-activated protein kinases signaling pathway culminating in the release of FSH and LH from storage compartments in the cytoplasm. FSH is only stored in secretory granules in the cytoplasm for short periods of time, whereas LH is stored for longer periods during the estrous cycle (Farnworth, 1995).

Why do estrous cycles stop during pregnancy?

Estrous cycles cease during pregnancy due to the prolonged presence of elevated progesterone from the CL, and placenta (in later pregnancy: ∼20% from approximately day 200). Following parturition estrous cycles recommence after a variable period of anestrus and anovulation.

Which ovarian structures regulate the estrous cycle?

A preovulatory follicle and the subsequently formed corpus luteum are the two primary ovarian structures that regulate the estrous cycle through secretion of estradiol and progesterone, respectively. Changes in a preovulatory follicle and corpus luteum, patterns of secretion of LH, estradiol and progesterone, and changes in ovarian blood flow during the ruminant estrous cycle are depicted in Fig. 3.1.

Which hormones regulate the pulse frequency of the luteal phase?

GnRH and hence LH pulse frequency are regulated in a negative feedback mechanism by estradiol and progesterone during the luteal phase, while in the follicular phase there is a positive feedback of estradiol (in the absence of progesterone) from the preovulatory follicle inducing the GnRH, LH, and FSH surges.

What is the estrous cycle?

The estrous cycle (derived from Latin oestrus; "frenzy", originally from Greek οἶστρος, oîstros; "gadfly") is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females.

When do estrous cycles start?

Estrous cycles start after sexual maturity in females and are interrupted by anestrous phases, otherwise known as "rest" phases, or by pregnancies. Typically, estrous cycles repeat until death. These cycles are widely variable in duration and frequency depending on the species.

What is the difference between oestrous and menstrual cycles?

One difference is that animals that have oestrous cycles resorb the endometrium if conception does not occur during that cycle. Animals that have menstrual cycles shed the endometrium through menstruation instead. Another difference is sexual activity.

Why is cattle estrous controlled?

Due to the widespread use of bovine animals in agriculture, cattle estrous cycles have been widely studied, and manipulated, in an effort to maximize profitability through reproductive management. Much estrous control in cattle is for the purpose of synchronization, a practice or set of practices most often used by cattle farmers to control the timing and duration of estrus in large herds.

How long does a cat's oestrous cycle last?

Even within species significant variability can be observed, thus cats may undergo an oestrous cycle of 3 to 7 weeks. Domestication can affect oestrous cycles due to changes in the environment. For most species, vaginal smear cytology may be used in order to identify oestrous cycle phases and durations.

What is the spelling of "oestrus"?

In British and most Commonwealth English, the spelling is oestrus or (rarely) œstrus. In all English spellings, the noun ends in -us and the adjective in -ous. Thus in North American English, a mammal may be described as "in estrus" when it is in that particular part of the estrous cycle .

How many times can a cat go into heat?

Some species, such as cats, cows and domestic pigs, are polyoestrous, meaning that they can go into heat several times per year. Seasonally polyoestrous animals or seasonal breeders have more than one oestrous cycle during a specific time of the year and can be divided into short-day and long-day breeders:

How often does estrus occur in cattle?

Estrus in cattle is commonly referred to as heat. It occurs every 18 to 24 days in sexually mature, open (non pregnant) female cattle when they are receptive to mounting activity by bulls or other cows or heifers. Accurate estrus detection is a key to efficient reproduction and to high milk production. The goal of a good estrus detection program is to identify estrus positively and accurately in all cycling animals and consequently to identify the animals not cycling. There are many changes which take place during the estrous cycle of a heifer or cow, but many of these changes are highly variable among animals and are impractical to measure routinely. In beef cattle or dairy animals where artificial insemination is the main means of breeding the females, Proper timing of the artificial insemination is necessary to accomplish a high percentage of conceptions in the dairy animals. Estrus detection directly affects calving interval and milk production and thus it can significantly increase the profits of a dairy farm. Several methods have been used to facilitate detection of estrus; these methods have focused on physical, behavioral, and physiological signs that are associated with estrus. Among the signs linked with estrus in dairy cows, standing to be mounted is the most reliable indicator of estrus. Aids such as chalking the tail head and chin ball markers have been used in the past to detect this estrus behavior. More recently, heat mount detectors have become more popular for the detection of estrus. Another sign commonly associated with estrus is an increase in physical activity and cows housed in free-stall barns may be four times as active during standing estrus than at other times.

How long does a doe cycle last?

During the peak of estrus, known as standing heat, a doe is receptive to a buck’s attention and can become pregnant. The time between the start of one estrus and the start of the next is called the estrous cycle. Different individual does have different estrous cycles. A doe’s cycle can range anywhere from 17 to 25 days, with 19 days being typical . Keeping track of the length of each of your doe’s cycles is a valuable breeding aid.

How old are camels when they start puberty?

There are several factors that can influence the age of the onset of puberty, such as Sexual activity Sexual activity has been reported to start as early as 2-3 years of age but usually they are not bred until they are 4-5 years old. sexual activity can continue until 20 years of age Breeding season Seasonal breeders Short breeding season Late September to March, Both male and female, are seasonal breeders Mating during the rainy, or cold season Outside of the breeding season mating activity ceases and the ovaries are inactive or only have a few, small follicles. Female Reproductive Female camel is a seasonal polyestrous animal. Induced ovulator Oestrus Cycle 23-27 Days Estrus Duration 4-7 days diestrus 15-20 day.

What do cows do in heat?

Cows in heat are more restless and alert to their surroundings. When allowed to interact with other cattle, cows coming into heat “pro estrus” and cows in heat persistently trail behind to try to mount other cows. During heat, they remain standing and alert while their herd mates are lying down and resting. Cattle may bellow more frequently during estrus. Although these are not definitive signs of heat, cows exhibiting such behavior should be watched closely for standing behavior

Do cows mount in heat?

Mounting activity is performed much less frequently by cows in mid cycle. Although mounting cannot be used as a true primary sign of heat, cows exhibiting such behavior should be watched closely for standing behavior.

How long does the estrous cycle last?

The estrous cycle has four phases, namely proestrus, estrus, metestrus and diestrus and lasts for 4 to 5 days [4] (Table ​(Table1).1).

Why is it important to determine the length and phase of the estrous cycle?

Determination of the length and phases of the estrous cycle and induction of estrus are useful in teaching and research and evaluating the effects of drugs/chemicals on the reproductive functions.

What is the proestrus phase?

The proestrus phase corresponds to the human follicular stage, which is associated with a rise in circulating estradiol concentrations and little surge in prolactin, this leads to a rise in LH and Follicle Stimulating Hormone (FSH) release. The peak in FSH concentration with an associated rapid decline in estradiol levels correlates to ovulation and estrus phase. Metestrus and diestrus are homologous to human early and late secretory stages of the reproductive cycle, respectively, with high levels of progesterone [12].

Why do we use estrous in research?

In reproductive function research, particularly those involving the use of female animals, mice and rats are commonly used, possibly due to their well characterized estrous cycle and secure handling. The short and precise length of estrous in these rodents [3, 4] also makes them very suitable. Determining the estrous phase is essential for selecting a female animal that will mate when paired with a male counterpart to achieve timed-pregnancy or tracking of estrous as a variable that may affect research [5]. Assessment of the estrous cycle in experimental animals is a useful measure of the integrity of the hypothalamic-pituitary-ovarian axis and the functioning reproductive status of the female reproductive system [4]. It can also be used to investigate the effects of drugs and chemicals on reproductive function [6] frequently expressed as a disruption in the typical morphology, cytology and histology of reproductive organs and alteration in the duration of particular phases of the estrous cycle.

What is the origin of the word "estrus"?

The word “estrus” was first used by Heape [13]. This is a Latin adaptation of the Greek word “oistros” which means “sexual season”, “gadfly”, “frenzy”, “sting” or “madness” [14]. Heape further named and defined the phases of the mammalian estrous cycle into proestrus, metestrus, diestrus and anestrus.

When does a female rat have her period?

In female rats, puberty is preceded by the pulsatile release of luteinizing hormone (LH) after the 4th postnatal week, approximately 30 days old [9]. This period is the anestrus and occurs about 8 to 9 days before the first proestrus [10]. The first proestrus, estrus, metestrus and diestrus then follow.

What are the phases of the menstrual cycle?

On the other hand, in humans, there are three phases of the menstrual cycle; the menstrual, proliferative (follicular), and secretory (luteal) phases. This cycle begins at puberty.

What is the reproductive cycle of a female?

ESTROUS CYCLE: Reproductive cycle of female, generally defined as period from one estrus to the next. Two phases:

What is the term for the period from one estrus to the next?

DEFINITIONS: ESTROUS CYCLE: Reproductive cycle of female, generally defined as period from one estrus to the next.  Two phases:  Follicular Phase  Luteal phase. 3. DEFINITIONS :  ESTRUS: Period of sexual receptivity.

How long does proestrus last?

PROESTRUSPROESTRUS • Begins when progesterone declines (luteolysis) and ends at onset of estrus • Lasts 2 to 5 days • Period of major endocrine transition – Progesterone dominance to estrogen dominance – FSH and LH responsible. 11.

What is Estrous Cycle?

Estrous cycle is the reproductive cycle of females of non-primate mammals. Therefore, estrous cycle occurs in females of non-primates such as cows, domestic pigs, sheep, goats, deer, elk, horses, hamsters, ferrets, canines, dioestrous, bears, foxes, and wolves, etc. The endometrium is reabsorbed by the walls of the uterus in these animals. Therefore, bleeding does not happen during the estrous cycle.

How long does the estrous cycle last?

Generally, the estrous cycle repeats after 21 days. Female animals are sexually active only during the estrus phase of the cycle. Estrous cycle is less complex than the menstrual cycle. It has four short phases: proestrus, estrus, metestrus and diestrus.

What is the Difference Between Estrous and Menstrual Cycle?

Estrous cycle refers to the reproductive cycle of females of non-primate mammals. Whereas, menstrual cycle refers to the reproductive cycle of females of primate mammals. So, this is the key difference between estrous and menstrual cycle. Another major difference between estrous and menstrual cycle is that the endometrium is reabsorbed during the estrous cycle while the endometrium is shed during the menstrual cycle.

What are the two cycles of a mammal?

Estrous and menstrual cycles take place in mammals. Both cycles start after sexual maturity in females and continue till menopause. These cycles are driven by reproductive hormones in females. They prepare female mammals for holding a child during pregnancy.

Why do females have oestrous cycles?

Reproductive hormones induce these cycles in females. These cycles happen in order to prepare female mammals for holding a child during pregnancy. Oestrous cycle occurs in non-primates such as cows, sheep, horse, rabbit, and pig, etc. The menstrual cycle occurs in primates such as monkeys, apes and humans, etc.

Which cycle is reabsorbed in monkeys?

The menstrual cycle occurs in primates such as monkeys, apes and humans, etc. Endometrium is reabsorbed in the estrous cycle while it is shed in the menstrual cycle.

What is the period of menstruation?

Furthermore, the menstrual cycle starts after sexual maturity (at puberty) and continues till menopause. There are three major phases of the menstrual cycle. They are menstrual, proliferative (follicular), and secretory (luteal) phases. Ovulation occurs in the ovulatory phase.

Estrous Cycle Stages

  • The descriptions below refer to the "typical" mammalian cycle. 1. proestrus - estrus - metestrus - diestrus
See more on embryology.med.unsw.edu.au

Rat Estrous Cycle

  • One of the best characterised polyestrous reproductive cycles, though different species of rats may differ in reproduction. In general, puberty occurs at 6-8 weeks when the estrous cycle commences each cycle is 4-5 days. The estrous cycle is polyestrous, more than one estrous cycle during a specific yearly time, with an estrous period of approximately 12 hours. See the review o…
See more on embryology.med.unsw.edu.au

Mouse Estrous Cycle

  • The mouse oestrus cycle is 4-6 days, with oestrus lasting less than 1 day. The estrous cycle stops during lactation except for one oestrus 12-20 hours postpartum. The information below refers to determining the stage of the estrous cycle in the mouse by the appearance of the vagina. 1. Estrous Diestrus- Vagina has a small opening and the tissues are bluish-purple in color and very …
See more on embryology.med.unsw.edu.au

Pig Estrous Cycle

  • The feedback systems between the ovaries, uterus, hypothalamus and pituitary gland govern a cycle of events that takes 18-21 days. If conception occurs this cyclic pattern is interrupted and pregnancy is maintained for approximately 114 days. Removal of the sucking stimulus at weaning triggers a new sequence of events. 1. Links: pig | PubMed- pig estrous cycle
See more on embryology.med.unsw.edu.au

Dog Estrous Cycle

  • Proestrus(9 days) - Precedes estrus, estradiol concentration increases as ovarian follicules mature and the uterus enlarges. The vaginal epithelium proliferates accompanied by diapedesis of erythro...
See more on embryology.med.unsw.edu.au

Bovine Estrous Cycle

  • Specific hormone concentrations are not shown in the above graph, only the relative hormone levels at different times during the cycle. 1. Links: cow
See more on embryology.med.unsw.edu.au

Historic

  • 1937 - Etymology and pronunciation of the word "oestrus" and its derivatives This word seems to offer more difficulties as to pronunciation and spelling than any other technical word in biology. Derived originally from the Greek oloxpos, signifying the gadfly, and taken over into Latin as oestrus, the word came secondarily to mean frenzy or strong desire. The Latin derivative is prop…
See more on embryology.med.unsw.edu.au

References

  • Reviews
    Westwood FR. (2008). The female rat reproductive cycle: a practical histological guide to staging. Toxicol Pathol , 36, 375-84. PMID: 18441260 DOI. Goldman JM, Murr AS & Cooper RL. (2007). The rodent estrous cycle: characterization of vaginal cytology and its utility in toxicological studies. …
  • Articles
    Caligioni CS. (2009). Assessing reproductive status/stages in mice. Curr Protoc Neurosci , Appendix 4, Appendix 4I. PMID: 19575469 DOI. Hubscher CH, Brooks DL & Johnson JR. (2005). A quantitative method for assessing stages of the rat estrous cycle. Biotech Histochem , 80, 79-87…
See more on embryology.med.unsw.edu.au

External Links

  • External Links Notice - The dynamic nature of the internet may mean that some of these listed links may no longer function. If the link no longer works search the web with the link text or name. Links to any external commercial sites are provided for information purposes only and should never be considered an endorsement. UNSW Embryology is provided as an educational resource…
See more on embryology.med.unsw.edu.au

Overview

The estrous cycle (from Latin oestrus 'frenzy', originally from Ancient Greek οἶστρος (oîstros) 'gadfly') is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous phases, otherwise known as "rest" phases, or by pregnancies. Typically, estrous cycles repeat until death. These cycles are widely variable in duration and frequency dep…

Differences from the menstrual cycle

Mammals share the same reproductive system, including the regulatory hypothalamic system that produces gonadotropin-releasing hormone in pulses, the pituitary gland that secretes follicle-stimulating hormone and luteinizing hormone, and the ovary itself that releases sex hormones, including estrogens and progesterone.
However, species vary significantly in the detailed functioning. One difference is that animals th…

Etymology and nomenclature

Estrus is derived via Latin oestrus ('frenzy', 'gadfly'), from Greek οἶστρος oîstros (literally 'gadfly', more figuratively 'frenzy', 'madness', among other meanings like 'breeze'). Specifically, this refers to the gadfly in Ancient Greek mythology that Hera sent to torment Io, who had been won in her heifer form by Zeus. Euripides used oestrus to indicate 'frenzy', and to describe madness. Homer used the word to describe panic. Plato also used it to refer to an irrational drive and to describe the soul "dri…

Four phases

A four-phase terminology is used in reference to animals with estrous cycles.
One or several follicles of the ovary start to grow. Their number is species-specific. Typically this phase can last as little as one day or as long as three weeks, depending on the species. Under the influence of estrogen, the lining of the uterus (endometrium) starts to develop. Some animals may experience vaginal secretions that could be bloody. The female is not yet sexually receptive…

Cycle variability

Estrous cycle variability differs among species, but cycles are typically more frequent in smaller animals. Even within species significant variability can be observed, thus cats may undergo an estrous cycle of 3 to 7 weeks. Domestication can affect estrous cycles due to changes in the environment. For most species, vaginal smear cytology may be used in order to identify estrous cycle phases and durations.

Frequency

Some species, such as cats, cows and domestic pigs, are polyestrous, meaning that they can go into heat several times per year. Seasonally polyestrous animals or seasonal breeders have more than one estrous cycle during a specific time of the year and can be divided into short-day and long-day breeders:
• Short-day breeders, such as sheep, goats, deer and elk are sexually active in fall or winter.

Specific species

The female cat in heat has an estrus of 14 to 21 days and is generally characterized as an induced ovulator, since coitus induces ovulation. However, various incidents of spontaneous ovulation have been documented in the domestic cat and various non-domestic species. Without ovulation, she may enter interestrus, which is the combined stages of diestrus and anestrus, before reentering estrus. With the induction of ovulation, the female becomes pregnant or undergoes a …

See also

• Mating system
• Musth
• Neutering
• Progesterone-releasing intravaginal device
• Reproductive cycle

Popular Posts:

  • 1. who died on antm
  • 2. what are the 5 deepest caves in the world
  • 3. are brio and bravo owned by the same company
  • 4. how spicy are chipotle peppers
  • 5. granny smith apple growing zone
  • 6. which of the following elements has the highest ionization energy
  • 7. alfabeto egipcio y su significado
  • 8. vatican city
  • 9. arien nation symbol
  • 10. best handheld vacuum for cars
    • A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 3 4 5 6 7 8 9
    Messages9TimelineExceptionsViews7RouteQueries7Models15Livewire0MailsGateSessionRequest
    8.3.21PHP Version2.16sRequest Duration2MBMemory UsageGET {post}Route
    • warninglog[07:42:26] LOG.warning: Creation of dynamic property Barryvdh\Debugbar\DataFormatter\QueryFormatter:...
    • warninglog[07:42:26] LOG.warning: Creation of dynamic property Barryvdh\Debugbar\DataFormatter\QueryFormatter:...
    • warninglog[07:42:26] LOG.warning: Callables of the form ["Swift_SmtpTransport", "Swift_Transport_EsmtpTranspor...
    • warninglog[07:42:26] LOG.warning: Creation of dynamic property Barryvdh\Debugbar\DataFormatter\SimpleFormatter...
    • warninglog[07:42:26] LOG.warning: Creation of dynamic property Barryvdh\Debugbar\DataFormatter\SimpleFormatter...
    • warninglog[07:42:27] LOG.warning: json_decode(): Passing null to parameter #1 ($json) of type string is deprec...
    • warninglog[07:42:27] LOG.warning: json_decode(): Passing null to parameter #1 ($json) of type string is deprec...
    • warninglog[07:42:27] LOG.warning: json_decode(): Passing null to parameter #1 ($json) of type string is deprec...
    • warninglog[07:42:27] LOG.warning: mt_rand(): Passing null to parameter #2 ($max) of type int is deprecated in ...
    warning
    • Booting (13.56ms)
    • Application (2.15s)
    • 1 x Application (99.35%)
      2.15s
      1 x Booting (0.63%)
      13.56ms
      7 templates were rendered
      • themes.DevBlog.content.post (resources/views/themes/DevBlog/content/post.blade.php)34blade
        Params
        0
        post
        1
        postContent
        2
        author
        3
        updated_at
        4
        bing_rich_snippet_text
        5
        bing_rich_snippet_link
        6
        bing_related_keywords
        7
        google_related_keywords
        8
        bing_news_title
        9
        bing_news_description
        10
        bing_videos
        11
        bing_images
        12
        bing_search_result_title
        13
        bing_search_result_description
        14
        bing_search_result_url
        15
        bing_paa_questions
        16
        bing_paa_answers
        17
        bing_slider_faq_questions
        18
        bing_slider_faq_answers
        19
        bing_pop_faq_questions
        20
        bing_pop_faq_answers
        21
        bing_tab_faq_questions
        22
        bing_tab_faq_answers
        23
        google_faq_questions
        24
        google_faq_answers
        25
        google_rich_snippet
        26
        google_search_result
        27
        indexedArray
        28
        total_images
        29
        total_videos
        30
        settings
        31
        url_current
        32
        menus
        33
        sidebar
      • themes.DevBlog.layouts.master (resources/views/themes/DevBlog/layouts/master.blade.php)41blade
        Params
        0
        __env
        1
        app
        2
        errors
        3
        post
        4
        postContent
        5
        author
        6
        updated_at
        7
        bing_rich_snippet_text
        8
        bing_rich_snippet_link
        9
        bing_related_keywords
        10
        google_related_keywords
        11
        bing_news_title
        12
        bing_news_description
        13
        bing_videos
        14
        bing_images
        15
        bing_search_result_title
        16
        bing_search_result_description
        17
        bing_search_result_url
        18
        bing_paa_questions
        19
        bing_paa_answers
        20
        bing_slider_faq_questions
        21
        bing_slider_faq_answers
        22
        bing_pop_faq_questions
        23
        bing_pop_faq_answers
        24
        bing_tab_faq_questions
        25
        bing_tab_faq_answers
        26
        google_faq_questions
        27
        google_faq_answers
        28
        google_rich_snippet
        29
        google_search_result
        30
        indexedArray
        31
        total_images
        32
        total_videos
        33
        settings
        34
        url_current
        35
        menus
        36
        sidebar
        37
        i
        38
        __currentLoopData
        39
        loop
        40
        item
      • themes.DevBlog.panels.head (resources/views/themes/DevBlog/panels/head.blade.php)41blade
        Params
        0
        __env
        1
        app
        2
        errors
        3
        post
        4
        postContent
        5
        author
        6
        updated_at
        7
        bing_rich_snippet_text
        8
        bing_rich_snippet_link
        9
        bing_related_keywords
        10
        google_related_keywords
        11
        bing_news_title
        12
        bing_news_description
        13
        bing_videos
        14
        bing_images
        15
        bing_search_result_title
        16
        bing_search_result_description
        17
        bing_search_result_url
        18
        bing_paa_questions
        19
        bing_paa_answers
        20
        bing_slider_faq_questions
        21
        bing_slider_faq_answers
        22
        bing_pop_faq_questions
        23
        bing_pop_faq_answers
        24
        bing_tab_faq_questions
        25
        bing_tab_faq_answers
        26
        google_faq_questions
        27
        google_faq_answers
        28
        google_rich_snippet
        29
        google_search_result
        30
        indexedArray
        31
        total_images
        32
        total_videos
        33
        settings
        34
        url_current
        35
        menus
        36
        sidebar
        37
        i
        38
        __currentLoopData
        39
        loop
        40
        item
      • themes.DevBlog.panels.header (resources/views/themes/DevBlog/panels/header.blade.php)41blade
        Params
        0
        __env
        1
        app
        2
        errors
        3
        post
        4
        postContent
        5
        author
        6
        updated_at
        7
        bing_rich_snippet_text
        8
        bing_rich_snippet_link
        9
        bing_related_keywords
        10
        google_related_keywords
        11
        bing_news_title
        12
        bing_news_description
        13
        bing_videos
        14
        bing_images
        15
        bing_search_result_title
        16
        bing_search_result_description
        17
        bing_search_result_url
        18
        bing_paa_questions
        19
        bing_paa_answers
        20
        bing_slider_faq_questions
        21
        bing_slider_faq_answers
        22
        bing_pop_faq_questions
        23
        bing_pop_faq_answers
        24
        bing_tab_faq_questions
        25
        bing_tab_faq_answers
        26
        google_faq_questions
        27
        google_faq_answers
        28
        google_rich_snippet
        29
        google_search_result
        30
        indexedArray
        31
        total_images
        32
        total_videos
        33
        settings
        34
        url_current
        35
        menus
        36
        sidebar
        37
        i
        38
        __currentLoopData
        39
        loop
        40
        item
      • themes.DevBlog.panels.navbar (resources/views/themes/DevBlog/panels/navbar.blade.php)41blade
        Params
        0
        __env
        1
        app
        2
        errors
        3
        post
        4
        postContent
        5
        author
        6
        updated_at
        7
        bing_rich_snippet_text
        8
        bing_rich_snippet_link
        9
        bing_related_keywords
        10
        google_related_keywords
        11
        bing_news_title
        12
        bing_news_description
        13
        bing_videos
        14
        bing_images
        15
        bing_search_result_title
        16
        bing_search_result_description
        17
        bing_search_result_url
        18
        bing_paa_questions
        19
        bing_paa_answers
        20
        bing_slider_faq_questions
        21
        bing_slider_faq_answers
        22
        bing_pop_faq_questions
        23
        bing_pop_faq_answers
        24
        bing_tab_faq_questions
        25
        bing_tab_faq_answers
        26
        google_faq_questions
        27
        google_faq_answers
        28
        google_rich_snippet
        29
        google_search_result
        30
        indexedArray
        31
        total_images
        32
        total_videos
        33
        settings
        34
        url_current
        35
        menus
        36
        sidebar
        37
        i
        38
        __currentLoopData
        39
        loop
        40
        item
      • themes.DevBlog.panels.footer (resources/views/themes/DevBlog/panels/footer.blade.php)41blade
        Params
        0
        __env
        1
        app
        2
        errors
        3
        post
        4
        postContent
        5
        author
        6
        updated_at
        7
        bing_rich_snippet_text
        8
        bing_rich_snippet_link
        9
        bing_related_keywords
        10
        google_related_keywords
        11
        bing_news_title
        12
        bing_news_description
        13
        bing_videos
        14
        bing_images
        15
        bing_search_result_title
        16
        bing_search_result_description
        17
        bing_search_result_url
        18
        bing_paa_questions
        19
        bing_paa_answers
        20
        bing_slider_faq_questions
        21
        bing_slider_faq_answers
        22
        bing_pop_faq_questions
        23
        bing_pop_faq_answers
        24
        bing_tab_faq_questions
        25
        bing_tab_faq_answers
        26
        google_faq_questions
        27
        google_faq_answers
        28
        google_rich_snippet
        29
        google_search_result
        30
        indexedArray
        31
        total_images
        32
        total_videos
        33
        settings
        34
        url_current
        35
        menus
        36
        sidebar
        37
        i
        38
        __currentLoopData
        39
        loop
        40
        item
      • themes.DevBlog.panels.scripts (resources/views/themes/DevBlog/panels/scripts.blade.php)41blade
        Params
        0
        __env
        1
        app
        2
        errors
        3
        post
        4
        postContent
        5
        author
        6
        updated_at
        7
        bing_rich_snippet_text
        8
        bing_rich_snippet_link
        9
        bing_related_keywords
        10
        google_related_keywords
        11
        bing_news_title
        12
        bing_news_description
        13
        bing_videos
        14
        bing_images
        15
        bing_search_result_title
        16
        bing_search_result_description
        17
        bing_search_result_url
        18
        bing_paa_questions
        19
        bing_paa_answers
        20
        bing_slider_faq_questions
        21
        bing_slider_faq_answers
        22
        bing_pop_faq_questions
        23
        bing_pop_faq_answers
        24
        bing_tab_faq_questions
        25
        bing_tab_faq_answers
        26
        google_faq_questions
        27
        google_faq_answers
        28
        google_rich_snippet
        29
        google_search_result
        30
        indexedArray
        31
        total_images
        32
        total_videos
        33
        settings
        34
        url_current
        35
        menus
        36
        sidebar
        37
        i
        38
        __currentLoopData
        39
        loop
        40
        item
      uri
      GET {post}
      middleware
      web, checkdate
      as
      post.show
      controller
      App\Http\Controllers\Frontend\json_data\PostController@show
      namespace
      where
      file
      app/Http/Controllers/Frontend/json_data/PostController.php:18-166
      7 statements were executed2.06s
      receivinghelpdeskask
      • select * from `posts` where `published_at` <= '2025-06-26 07:42:27' and `slug` = 'estrous-cycle-in-animals-examples' and `posts`.`deleted_at` is null limit 1
        2.44ms/app/Providers/RouteServiceProvider.php:54receivinghelpdeskask
        Metadata
        Bindings
        • 0. 2025-06-26 07:42:27
        • 1. estrous-cycle-in-animals-examples
        Backtrace
        • 15. /app/Providers/RouteServiceProvider.php:54
        • 18. /vendor/laravel/framework/src/Illuminate/Routing/Router.php:842
        • 19. Route binding:39
        • 20. /vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php:167
        • 21. /vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/VerifyCsrfToken.php:78
      • select * from `json_post_contents` where `json_post_contents`.`post_id` = 42704 and `json_post_contents`.`post_id` is not null and `rewrite_id` = 0
        5.73msmiddleware::checkdate:30receivinghelpdeskask
        Metadata
        Bindings
        • 0. 42704
        • 1. 0
        Backtrace
        • 19. middleware::checkdate:30
        • 20. /vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php:167
        • 21. /vendor/laravel/jetstream/src/Http/Middleware/ShareInertiaData.php:61
        • 22. /vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php:167
        • 23. /vendor/laravel/framework/src/Illuminate/Routing/Middleware/SubstituteBindings.php:50
      • select * from `nova_menu_menus` where `slug` = 'header' limit 1
        580μs/vendor/outl1ne/nova-menu-builder/src/helpers.php:32receivinghelpdeskask
        Metadata
        Bindings
        • 0. header
        Backtrace
        • 15. /vendor/outl1ne/nova-menu-builder/src/helpers.php:32
        • 17. /vendor/laravel/framework/src/Illuminate/Routing/Controller.php:54
        • 18. /vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php:45
        • 19. /vendor/laravel/framework/src/Illuminate/Routing/Route.php:261
        • 20. /vendor/laravel/framework/src/Illuminate/Routing/Route.php:205
      • select * from `nova_menu_menu_items` where `nova_menu_menu_items`.`menu_id` = 1 and `nova_menu_menu_items`.`menu_id` is not null and `parent_id` is null order by `parent_id` asc, `order` asc, `name` asc
        610μs/vendor/outl1ne/nova-menu-builder/src/Models/Menu.php:35receivinghelpdeskask
        Metadata
        Bindings
        • 0. 1
        Backtrace
        • 19. /vendor/outl1ne/nova-menu-builder/src/Models/Menu.php:35
        • 20. /vendor/outl1ne/nova-menu-builder/src/helpers.php:33
        • 22. /vendor/laravel/framework/src/Illuminate/Routing/Controller.php:54
        • 23. /vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php:45
        • 24. /vendor/laravel/framework/src/Illuminate/Routing/Route.php:261
      • select * from `nova_menu_menu_items` where `nova_menu_menu_items`.`parent_id` in (1) order by `order` asc
        320μs/vendor/outl1ne/nova-menu-builder/src/Models/Menu.php:35receivinghelpdeskask
        Metadata
        Backtrace
        • 24. /vendor/outl1ne/nova-menu-builder/src/Models/Menu.php:35
        • 25. /vendor/outl1ne/nova-menu-builder/src/helpers.php:33
        • 27. /vendor/laravel/framework/src/Illuminate/Routing/Controller.php:54
        • 28. /vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php:45
        • 29. /vendor/laravel/framework/src/Illuminate/Routing/Route.php:261
      • select `id`, `post_title`, `slug` from `posts` where `status` = 'publish' and `posts`.`deleted_at` is null order by RAND() limit 10
        2.05s/app/View/Composers/SidebarView.php:22receivinghelpdeskask
        Metadata
        Bindings
        • 0. publish
        Backtrace
        • 14. /app/View/Composers/SidebarView.php:22
        • 15. /app/View/Composers/SidebarView.php:12
        • 16. /vendor/laravel/framework/src/Illuminate/View/Concerns/ManagesEvents.php:124
        • 17. /vendor/laravel/framework/src/Illuminate/View/Concerns/ManagesEvents.php:162
        • 20. /vendor/laravel/framework/src/Illuminate/View/Concerns/ManagesEvents.php:177
      • select * from `fake_users` where `fake_users`.`id` = 26198 limit 1
        700μsview::2dd102cf0462e89a4d4d8bc77355d767652bf9aa:15receivinghelpdeskask
        Metadata
        Bindings
        • 0. 26198
        Backtrace
        • 21. view::2dd102cf0462e89a4d4d8bc77355d767652bf9aa:15
        • 23. /vendor/laravel/framework/src/Illuminate/Filesystem/Filesystem.php:108
        • 24. /vendor/laravel/framework/src/Illuminate/View/Engines/PhpEngine.php:58
        • 25. /vendor/livewire/livewire/src/ComponentConcerns/RendersLivewireComponents.php:69
        • 26. /vendor/laravel/framework/src/Illuminate/View/Engines/CompilerEngine.php:61
      App\Models\FakeUser
      1
      Outl1ne\MenuBuilder\Models\MenuItem
      1
      Outl1ne\MenuBuilder\Models\Menu
      1
      App\Models\JsonPostContent
      1
      App\Models\Post
      11
          _token
          SMbGHLTlWvCf7iNVb6GOqgyoXodXnk5ZyMzlJQ8v
          _previous
          array:1 [ "url" => "https://receivinghelpdesk.com/ask/estrous-cycle-in-animals-examples" ]
          _flash
          array:2 [ "old" => [] "new" => [] ]
          PHPDEBUGBAR_STACK_DATA
          []
          path_info
          /estrous-cycle-in-animals-examples
          status_code
          200
          status_text
          OK
          format
          html
          content_type
          text/html; charset=UTF-8
          request_query
          []
          request_request
          []
          request_headers
            0 of 0   
          array:24 [▼
  "cf-ipcountry" => array:1 [▶
    0 => "US"
  ]
  "cf-connecting-ip" => array:1 [▶
    0 => "216.73.216.194"
  ]
  "cdn-loop" => array:1 [▶
    0 => "cloudflare; loops=1"
  ]
  "sec-fetch-site" => array:1 [▶
    0 => "none"
  ]
  "accept" => array:1 [▶
    0 => "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7"
  ]
  "user-agent" => array:1 [▶
    0 => "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)"
  ]
  "upgrade-insecure-requests" => array:1 [▶
    0 => "1"
  ]
  "sec-ch-ua-platform" => array:1 [▶
    0 => ""Windows""
  ]
  "sec-ch-ua-mobile" => array:1 [▶
    0 => "?0"
  ]
  "sec-ch-ua" => array:1 [▶
    0 => ""Chromium";v="130", "HeadlessChrome";v="130", "Not?A_Brand";v="99""
  ]
  "cache-control" => array:1 [▶
    0 => "no-cache"
  ]
  "pragma" => array:1 [▶
    0 => "no-cache"
  ]
  "sec-fetch-dest" => array:1 [▶
    0 => "document"
  ]
  "cf-ray" => array:1 [▶
    0 => "95592e03bddadd6d-ORD"
  ]
  "accept-encoding" => array:1 [▶
    0 => "gzip, br"
  ]
  "priority" => array:1 [▶
    0 => "u=0, i"
  ]
  "sec-fetch-user" => array:1 [▶
    0 => "?1"
  ]
  "sec-fetch-mode" => array:1 [▶
    0 => "navigate"
  ]
  "cf-visitor" => array:1 [▶
    0 => "{"scheme":"https"}"
  ]
  "connection" => array:1 [▶
    0 => "close"
  ]
  "x-forwarded-proto" => array:1 [▶
    0 => "https"
  ]
  "x-forwarded-for" => array:1 [▶
    0 => "216.73.216.194, 172.69.6.210"
  ]
  "x-server-addr" => array:1 [▶
    0 => "154.12.239.204"
  ]
  "host" => array:1 [▶
    0 => "receivinghelpdesk.com"
  ]
]
          request_server
            0 of 0   
          array:55 [▼
  "USER" => "runcloud"
  "HOME" => "/home/runcloud"
  "SCRIPT_NAME" => "/ask/index.php"
  "REQUEST_URI" => "/ask/estrous-cycle-in-animals-examples"
  "QUERY_STRING" => ""
  "REQUEST_METHOD" => "GET"
  "SERVER_PROTOCOL" => "HTTP/1.0"
  "GATEWAY_INTERFACE" => "CGI/1.1"
  "REDIRECT_URL" => "/ask/estrous-cycle-in-animals-examples"
  "REMOTE_PORT" => "51982"
  "SCRIPT_FILENAME" => "/home/runcloud/webapps/ReceivingHelpDesk/ask/index.php"
  "SERVER_ADMIN" => "you@example.com"
  "CONTEXT_DOCUMENT_ROOT" => "/home/runcloud/webapps/ReceivingHelpDesk/"
  "CONTEXT_PREFIX" => ""
  "REQUEST_SCHEME" => "http"
  "DOCUMENT_ROOT" => "/home/runcloud/webapps/ReceivingHelpDesk/"
  "REMOTE_ADDR" => "172.69.6.210"
  "SERVER_PORT" => "80"
  "SERVER_ADDR" => "127.0.0.1"
  "SERVER_NAME" => "receivinghelpdesk.com"
  "SERVER_SOFTWARE" => "Apache/2.4.63 (Unix) OpenSSL/1.1.1f"
  "SERVER_SIGNATURE" => ""
  "LD_LIBRARY_PATH" => "/RunCloud/Packages/apache2-rc/lib"
  "PATH" => "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
  "HTTP_CF_IPCOUNTRY" => "US"
  "HTTP_CF_CONNECTING_IP" => "216.73.216.194"
  "HTTP_CDN_LOOP" => "cloudflare; loops=1"
  "HTTP_SEC_FETCH_SITE" => "none"
  "HTTP_ACCEPT" => "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7"
  "HTTP_USER_AGENT" => "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)"
  "HTTP_UPGRADE_INSECURE_REQUESTS" => "1"
  "HTTP_SEC_CH_UA_PLATFORM" => ""Windows""
  "HTTP_SEC_CH_UA_MOBILE" => "?0"
  "HTTP_SEC_CH_UA" => ""Chromium";v="130", "HeadlessChrome";v="130", "Not?A_Brand";v="99""
  "HTTP_CACHE_CONTROL" => "no-cache"
  "HTTP_PRAGMA" => "no-cache"
  "HTTP_SEC_FETCH_DEST" => "document"
  "HTTP_CF_RAY" => "95592e03bddadd6d-ORD"
  "HTTP_ACCEPT_ENCODING" => "gzip, br"
  "HTTP_PRIORITY" => "u=0, i"
  "HTTP_SEC_FETCH_USER" => "?1"
  "HTTP_SEC_FETCH_MODE" => "navigate"
  "HTTP_CF_VISITOR" => "{"scheme":"https"}"
  "HTTP_CONNECTION" => "close"
  "HTTP_X_FORWARDED_PROTO" => "https"
  "HTTP_X_FORWARDED_FOR" => "216.73.216.194, 172.69.6.210"
  "HTTP_X_SERVER_ADDR" => "154.12.239.204"
  "HTTP_HOST" => "receivinghelpdesk.com"
  "HTTPS" => "on"
  "REDIRECT_STATUS" => "200"
  "REDIRECT_HTTPS" => "on"
  "FCGI_ROLE" => "RESPONDER"
  "PHP_SELF" => "/ask/index.php"
  "REQUEST_TIME_FLOAT" => 1750903946.9378
  "REQUEST_TIME" => 1750903946
]
          request_cookies
          []
          response_headers
            0 of 0   
          array:7 [▼
  "content-type" => array:1 [▶
    0 => "text/html; charset=UTF-8"
  ]
  "cache-control" => array:1 [▶
    0 => "private, must-revalidate"
  ]
  "date" => array:1 [▶
    0 => "Thu, 26 Jun 2025 02:12:27 GMT"
  ]
  "pragma" => array:1 [▶
    0 => "no-cache"
  ]
  "expires" => array:1 [▶
    0 => -1
  ]
  "set-cookie" => array:2 [▶
    0 => "XSRF-TOKEN=eyJpdiI6IjVMTGJBY1dLWnFYUktQa0NReG1TZ2c9PSIsInZhbHVlIjoiczlhT3U3TDVLMDZqTVQ5Q0FSY1JYdFhZUm5NN3Q2RjB6UXVScGo5d0F2Ukl4bjVoWXRXeHFJVDF0YkdxVWpwcmJzMUdZRGZ3OGNHdVJnWlhyajVJSDVTamVweC91bTVDWisvWFFyMGlrdURWaDl5Z21xZlkzelAyMTZKYUNkTW0iLCJtYWMiOiI3OTY2MzI0MTY4MmY5ZTJjMjU2YTNkMWJhNWQwYjc5MmNhODQ0NGY5OTZhY2MxNzBjMWEwM2ExNDZlYTAzMzNmIiwidGFnIjoiIn0%3D; expires=Thu, 26-Jun-2025 04:12:29 GMT; Max-Age=7200; path=/; samesite=lax ◀XSRF-TOKEN=eyJpdiI6IjVMTGJBY1dLWnFYUktQa0NReG1TZ2c9PSIsInZhbHVlIjoiczlhT3U3TDVLMDZqTVQ5Q0FSY1JYdFhZUm5NN3Q2RjB6UXVScGo5d0F2Ukl4bjVoWXRXeHFJVDF0YkdxVWpwcmJzMUdZR ▶"
    1 => "askhelpdesk_session=eyJpdiI6IlMvZXArb2hBaHplSXAyZUZyL3lCREE9PSIsInZhbHVlIjoibXdOK1QwY25YbVYrTEZyQ0FuNUswbE9VYVMyWThDL011UURIVG5UeHczZk53SFBvV3E3RDlhVkRUOXlpbE5MbDVSSy9JQ002Y2NYRW45cHdPeklWdERpeXBCYitWK1VvUHp3dWl1UmNuNGJzYVRvV2gyMEE5aU5NRDJUTkhPTmMiLCJtYWMiOiI5MjY5NTM2N2EwNmVhZjBjMTRiMmNhMmE1MWYyMTAyNDAwNGQ3ZmNkMTEzZGIwNGM5MDY5ZDlmM2NiMmU1ZjJmIiwidGFnIjoiIn0%3D; expires=Thu, 26-Jun-2025 04:12:29 GMT; Max-Age=7200; path=/; httponly; samesite=lax ◀askhelpdesk_session=eyJpdiI6IlMvZXArb2hBaHplSXAyZUZyL3lCREE9PSIsInZhbHVlIjoibXdOK1QwY25YbVYrTEZyQ0FuNUswbE9VYVMyWThDL011UURIVG5UeHczZk53SFBvV3E3RDlhVkRUOXlpbE5M ▶"
  ]
  "Set-Cookie" => array:2 [▶
    0 => "XSRF-TOKEN=eyJpdiI6IjVMTGJBY1dLWnFYUktQa0NReG1TZ2c9PSIsInZhbHVlIjoiczlhT3U3TDVLMDZqTVQ5Q0FSY1JYdFhZUm5NN3Q2RjB6UXVScGo5d0F2Ukl4bjVoWXRXeHFJVDF0YkdxVWpwcmJzMUdZRGZ3OGNHdVJnWlhyajVJSDVTamVweC91bTVDWisvWFFyMGlrdURWaDl5Z21xZlkzelAyMTZKYUNkTW0iLCJtYWMiOiI3OTY2MzI0MTY4MmY5ZTJjMjU2YTNkMWJhNWQwYjc5MmNhODQ0NGY5OTZhY2MxNzBjMWEwM2ExNDZlYTAzMzNmIiwidGFnIjoiIn0%3D; expires=Thu, 26-Jun-2025 04:12:29 GMT; path=/ ◀XSRF-TOKEN=eyJpdiI6IjVMTGJBY1dLWnFYUktQa0NReG1TZ2c9PSIsInZhbHVlIjoiczlhT3U3TDVLMDZqTVQ5Q0FSY1JYdFhZUm5NN3Q2RjB6UXVScGo5d0F2Ukl4bjVoWXRXeHFJVDF0YkdxVWpwcmJzMUdZR ▶"
    1 => "askhelpdesk_session=eyJpdiI6IlMvZXArb2hBaHplSXAyZUZyL3lCREE9PSIsInZhbHVlIjoibXdOK1QwY25YbVYrTEZyQ0FuNUswbE9VYVMyWThDL011UURIVG5UeHczZk53SFBvV3E3RDlhVkRUOXlpbE5MbDVSSy9JQ002Y2NYRW45cHdPeklWdERpeXBCYitWK1VvUHp3dWl1UmNuNGJzYVRvV2gyMEE5aU5NRDJUTkhPTmMiLCJtYWMiOiI5MjY5NTM2N2EwNmVhZjBjMTRiMmNhMmE1MWYyMTAyNDAwNGQ3ZmNkMTEzZGIwNGM5MDY5ZDlmM2NiMmU1ZjJmIiwidGFnIjoiIn0%3D; expires=Thu, 26-Jun-2025 04:12:29 GMT; path=/; httponly ◀askhelpdesk_session=eyJpdiI6IlMvZXArb2hBaHplSXAyZUZyL3lCREE9PSIsInZhbHVlIjoibXdOK1QwY25YbVYrTEZyQ0FuNUswbE9VYVMyWThDL011UURIVG5UeHczZk53SFBvV3E3RDlhVkRUOXlpbE5M ▶"
  ]
]
          session_attributes
            0 of 0   
          array:4 [▼
  "_token" => "SMbGHLTlWvCf7iNVb6GOqgyoXodXnk5ZyMzlJQ8v"
  "_previous" => array:1 [▶
    "url" => "https://receivinghelpdesk.com/ask/estrous-cycle-in-animals-examples"
  ]
  "_flash" => array:2 [▶
    "old" => []
    "new" => []
  ]
  "PHPDEBUGBAR_STACK_DATA" => []
]