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Stages of Pregnancy in Mares

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Even during the random season, it is very important as soon as possible, after the mating of each mare, to establish whether the draw has occurred or if the mare has remained idle. Early diagnostics of foals gives an opportunity not only to achieve a higher foraging, but also to organize the further use, keeping and feeding of horses on the farm, breaking mares into single and foals, and the latter into groups according to the timing of the expected foraging. With the onset of foal, the uterus becomes calmer after about a month and eats food better. However, by the appearance of the mares and by the movements of the fetus, it is possible to determine the foal only at the 7-8th month. In some uterus, in the fifth month of the season, the sternum increases significantly and the abdomen drops. 2 months before the foal, the udder begins to gradually increase.

As an option, early diagnosis of foals is performed by the rectal method - by palpating the uterus and its horns with a hand inserted through the rectum. In this way, it is possible to establish the draw in 3-4 weeks after mare mating.

The duration of the expected flare is determined from the day of the last cage by adding 11 months.

The foal of mares usually occurs at night, when the stable is quiet and calm. You need to prepare for a foal. Grooms and other stable workers should know the timing of the expected draws of each uterus.

In the last days before a foal, you should especially carefully watch the mare. Before the foal, the udder swells strongly, dried colostrum drops appear on the nipples, and sometimes it even flows out by itself. Immediately before the foal, the mare becomes restless: he walks along the stall, with his foot he corrects the litter, then he lies down, then he again gets to his feet.

Usually, foraging in mares lasts 20–40 minutes, passes easily and does not require outside help. The foal mare should not be disturbed so that premature breakage of the umbilical cord does not occur due to its sudden movements. Bandaging and cutting off or cutting the umbilical cord can be done no sooner than the pulsation of blood stops in it.

A healthy foal in 20-30 minutes. after birth, able to stand up and start sucking mother.

After foaming, the mare should be given water to drink to quench his thirst, but only a few sips. Drink and give food should be in 2-3 hours. The first 1-2 days, the concentrates give in a reduced amount in the form of talkers and cereals. Hay should be of good quality. The full-grown mare should be transferred to a complete diet carefully and gradually over a period of 5-6 days.

3-4 days after the foal, the mares should be taken out for a walk or kept in the brew along with the foals when they are kept stable.

Walking for foals should begin in good, calm weather from 10-15 minutes. and then gradually lengthen.
After the foal, in any case, before the mare is pastured in the pasture, she needs to trim and clear the hooves.

Clinical methods

In order to diagnose the presence of stallion in a horse or its absence for two to three decades, starting from 4 days after fertilization, the animal is checked daily for reflexes. To do this, use a manual breakdown or release several horses into the corral with a horned stallion and monitor the presence or absence of sexual hunting in the female.

Outdoor surveillance

This method of diagnosing the stage of pregnancy of mares is unsafe and suggests that the specialist knows the features of the horse’s behavior. Particularly nervous individuals and mares, foals for the first time, can hit with a hoof, pressed against the wall of the stall. You should pay attention to the horse’s ears: if they are pressed to the head and pulled apart, you should be vigilant to avoid an accident.

For safety, it is not recommended to conduct research in stalls and confined spaces. It is very important to conduct early diagnostics of the pregnancy stage in mares with an assistant who can keep the front leg of the animal raised. You can also use reins or random harness.

Using a random harness to inspect a mare

To inspect the horse you need good uniform lighting. This can be done both outdoors and in a well-equipped stall. Being on the same plane with the body of the animal, and this can be achieved by taking a few steps directly against the animal. In this position, changes in the shape of the abdomen are especially pronounced. Try to make the mare stand upright at this time, do not kick over and do not flinch.

Visual signs of mare's draw

The apparent absence of the left hungry fossa and protrusion of the abdominal wall on the same side indicate the second half of the draw. At the end of pregnancy, the lower left abdominal wall sags.

Pay attention to the left wall of the peritoneum when brooding or drinking a horse. If the abdominal wall trembles, then this indicates the movement of the fetus. It must be remembered that the cold water given to animals for diagnosis can cause abortion.

If the mare is not foal, then due to the anatomical features of the intestine, the right abdominal wall bulges out, and the hungry fossa is not visually visible.

In the final stage of the horse’s pregnancy, shortly before the birth of the horse, the vulva swells and increases, the folds are smoothed. You can also observe swelling on the periphery of the hind limbs. Rear and side examination allow you to see an increase in the mammary gland, the skin on it is straightened.

Palpation with the back of the hand reveals swelling of the tissues of the udder and vulva, as well as a marked decrease in body temperature in these parts. With light pressure on the swollen tissue with a finger, a fossa is formed. Tissue alignment does not occur immediately, it takes some time.
Drops of a viscous substance of light yellow color can be squeezed out of the nipples.

It is better to wait for the animals to fully relax in the abdominal wall and only after that proceed to palpating the fetus.

Turning the horse's head to the left and holding the folds of skin over the withers soothe the animal. You can also capture the skin over 10-13 vertebrae. Thus, the voltage is removed.

A specialist who examines the fetus must adhere to certain standards. It is preferable to stand on the left side of the horse, looking at the croup and grabbing the skin over the withers with the left hand. Palpation is carried out with the right hand. It consists in the fact that you need to push deep into the abdominal wall and quickly release your hand without removing it from the body of the mare. If the fetus is present, then a push from the solid is felt. For a more accurate result, it is necessary to carry out several such actions in different directions.

The push comes from the fact that the fetus, shifted to the side, necessarily returns to its original place. It must be remembered that such studies are carried out only by the palm. The use of a fist, as well as blows are strictly prohibited.

In order to listen to the fetal heartbeat, the horse must be covered with a cloth, and then with a stethoscope to listen, on the palpation sites.

The above method for diagnosing the stage of pregnancy in mares is simple and affordable. No special conditions are required for its implementation. But you need to know that the external method determines only the presence of lottery.

Vaginal diagnostic method according to Benesh-Kurasawa

This method involves the use of a vaginal specimen to take a smear of mucus, and then examine it under a microscope. When introducing a mirror, pay attention to the reaction of the animal. The mucous membrane of the vagina and cervix is ​​subjected to a thorough examination.

For the safety of those examining the horse’s feet, it is better to put on fetters. This will protect against a sudden blow. Mandatory help of a second person. He will raise the head of the mare and help her to shift the center of gravity back.

The labia of the animal is washed and disinfected. A dry and sterile vaginal mirror of Polyansky or Skatkin is inserted into the vulva and squeezed so that the instrument's planes open as much as possible. The horse is mounted with croup to the lighting. Reflecting from the shiny planes of the mirror, the light makes it possible to examine the mucous surface of the vagina and the cervix.

Usually the introduction of a mirror of a foal horse is fraught with some difficulty, since the vaginal walls are covered with thick-looking and sticky mucus to the touch.

The planes of the used mirror are covered with stripes and lumps of cloudy gray homogeneous substance. Lumps of mucus are viscous and easily roll into balls.

The mucous membrane of the vagina becomes dull and pale from the third week of pregnancy. If the horse has a narrow vagina, you must be extremely careful during the study to avoid stagnation from squeezing the venous vessels of the vagina. During this period, the mouth of the cervix is ​​closed with a dense plug of thick gray mucus. There is a cervical displacement. Usually to the front edge of the pubic bones, often to the right or left, and even descends into the abdominal cavity.

Studies of the reaction of vaginal mucus show the following. At the beginning of pregnancy, it is neutral, and at the end it is acidic.

Rectal method

Research is carried out only in warm and spacious rooms. Because narrow, cluttered, poor, with potholes, the floor with sudden movements of the animal can lead to injury to the hand. A rectal method for diagnosing the stage of pregnancy in horse mares is best done together.

The assistant stands on the right and takes the horse’s tail to his side, giving the researcher, who is to the left of the animal, leaning on the croup, carefully and slowly insert his fingers folded in a cone into the anus of the mare. First you need to gently massage the skin of the anus so that it relaxes. To expand the lumen of the anus, you need to strain your fingers so that a gap forms. This leads to the act of defecation in the horse and contributes to the complete release of the rectum.

For safety reasons, the assistant should ensure that tail hair does not get into the anus. They irritate the mucous membrane, and can also damage the skin of the researcher.

Rectal examination of the hand

Ampuloid expansion is located in the pelvic region and is attached by connective tissue to the bones of the pelvis and the vestibule of the vagina, therefore it is a conditionally motionless part of the rectum. It is in this extension that the brush from the anus gets into. Further, the rectum narrows and forms several kinks and folds.

The uterus can be palpated with four fingers advanced in the narrowed region of the rectum, while the thumb remains in the ampulla region. The first thing that is investigated is the ovaries. The arm should be on the projection of the 4-5 lumbar vertebra. At this depth, the hand should be advanced to the hungry fossa, fingers bent a little and smoothly moved along the peritoneal wall to the pelvis. The ovary is excellent in density and rounded shape. When approaching the ovary, the tense edge of the uterine mesentery, also called the ovarian ligament, gets into the arm.

When examining the ovaries in a horse, their size, content, shape and other parameters are determined. It is easier to start on the left side and advance the arm along the oviduct to the top of the left uterine horn and grab it between the palm and the bent fingers. Sliding along the horn to the body of the uterus, an examination is made for the size, texture and shape of the uterine horn. After probing the body, without removing their hands, they move the brush to the right and examine this side in the opposite direction (horn, egg duct, ovary).

The uterine arteries are also an important part of the study. Their location is the same as in cows, with the only difference being that the middle uterine artery in horses departs from the external iliac artery, and in cows from the umbilical artery.

The rectal method of research makes it possible to identify the characteristic signs of a draw or non-draw condition.

Signs of lack of lottery

Ovaries of non-stallion horses 3-5 cm in size and bean-shaped. The left one is quite mobile, located at the level of the iliac wing hillock. The right one is not so mobile and is located above the wing tubercle.

Both horns of the uterus are the same, flat and flabby, located in the abdominal cavity and diverge from the uterus to the sides in the forward and upward directions. When probing, they take a rounded shape and shrink. The development of the uterine arteries is uniform and the pulsation is carried out with equal force.

1 month

Conclusion with this period of pregnancy should be very careful. Especially when old mares are diagnosed. Any doubt raises the need for re-examination after about two weeks.

A significant increase in the ovary from the pregnant horn. This increase is due to the presence of the corpus luteum, which is well palpated. The ovary is a little lowered, little mobile. The horns of the uterus are rounded, become elastic and asymmetric. The enlarged base of one of them resembles a goose egg in shape and size. In the enlarged area is a liquid, 200-250 ml. Her fluctuations are not sustained. When probing, there is no contraction of the horn, and the horns themselves are located on top of the intestines.

2 month

Stretched ligament of the ovary from the side of the pregnant uterine horn. Ovarian prolapse to the axis of the pelvis. The asymmetry of the uterine horns is even more pronounced, because the uterine body itself has also increased. Twice the increase in a pregnant horn compared to a non-pregnant one. The body of the uterus also reaches large sizes. The outgoing horns are sausage-shaped, are in the same position, on top of the intestine. At this time, with careful palpation, there is an oscillation of the amniotic fluid, its amount reaches 800 ml.

3 month

Three-fold increase in pregnant horn from non-pregnant. The uterus is irregular in shape with layers, the size of a baby ball. Fluctuations in the amniotic fluid are distinct. They are felt in the body of the uterus, the pregnant horn and at the base of the non-pregnant horn. Liquids approximately 2 liters. Sometimes at this time you can already feel the fetus. The cervix is ​​dense, 6-8 cm long, 4-6 cm wide, occupies an oblique and longitudinal position to the axis of the pelvis.

When researching at this time, an error can occur, since the uterus can be confused with a full bladder. To avoid this, you must definitely probe the place where the horns of the uterus diverge, and also find the cervix, how it relates to the fetal bladder.

The uterus and ovaries descend deep into the abdominal cavity. The location of the ovary from the side of the pregnant horn is almost at the level and slightly in front of the pubic fusion.

4 month

The size of the uterus resembles a basketball. Feeling reveals obvious fluctuations of amniotic fluid. Uterine ligament of a pregnant horn in a tense state. At the front edge of the bottom of the pelvic cavity is the cervix. Palpation of the fetus is almost always successful. The ovaries are lowered to the bottom of the pelvis or even lower and are not far from each other. The middle uterine artery has a significant increase in diameter from the side of the pregnant horn with respect to the same artery near the non-pregnant horn. It is possible to feel a slight vibration of the artery.

5 month

Palpation of the fetus can be done with a deeply inserted arm, because the uterus is very deep in the abdominal cavity. From the side of the pregnant horn, a pronounced vibration of the middle uterine artery. There is also slight arterial vibration of the artery from the side of the other horn. Other symptoms remain unchanged from the fourth month of the draw.

The location of the fetus before the second half of pregnancy

6 month

The body of the uterus with horns and neck is almost inaccessible to palpation.It is located at the bottom of the abdominal cavity. Also, the fetus located on the lower abdomen is not accessible to palpating. With a deeply inserted hand, it is possible to palpate the fetus in the area of ​​pubic fusion in mares no more than average size. The middle uterine arteries are enlarged differently. Also, vibration, more reminiscent of "buzzing", of an artery from the side of a pregnant horn, predominates.

7, 8 months

Even deeply entering the hand, it is not always possible to probe the fetus, only some parts at the level of the third lumbar vertebra. It is not possible to determine the contours of the uterus due to its huge size. If you lightly push your hand on the uterus, the fetus will move down, but immediately rise to its original place, and the palm will feel a push. A noticeable further increase in the middle uterine arteries. You can feel the vibration by pressing them with your fingers. A pulsation of the posterior uterine artery appears on the side of the pregnant horn.

10 month

Due to the prohibitive size of the uterus, the cervix and part of the fetus are rooted in the pelvic cavity. Very strong vibration of the uterine arteries allows you to quickly find and palpate them. Their diameter is increased. Excellent palpation of the fetus.

The location of the fetus before childbirth

Vaginal smear method

To determine the stallion of a horse, a smear is taken from the vagina. Before the procedure, the mares thoroughly wash the external genitalia. To do this, use warm water and soap. After insertion into the vagina of the speculum with a long spoon with rounded edges, mucus is collected from the upper vaginal fornix.

A sterile, dense cotton swab is also used for these purposes. Slime is applied to a fat-free glass slide, a smear is made with another glass and dried in air. After drying, the smear must be fixed with methyl alcohol for 5 minutes, then about half an hour is stained with Giemsa (1 ml of distilled water - 2 drops of paint), the paint is washed off and dried well again.

When examined under a glass microscope, in a smear of mucus from a pregnant horse, there are balls of blue mucus, ciliated epithelial cells, random squamous cells, and almost never leukocytes. In the absence of stupidity, squamous cells, large numbers of neutrophilic leukocytes and very rarely ciliated epithelial cells are found in the mucus. Never find balls of mucus. A smear consists of an even layer of mucus.

Macroscopy of the vaginal cavity in the presence of clinical signs is an additional study to diagnose the presence of pregnancy in a mare.

The 3rd week of draw is marked by the fact that the entire sheath of the vagina is covered with mucus, which is viscous, thick and has a cloudy color. It is this mucus that makes it difficult to insert a mirror into the vagina. In the future, the vaginal mucosa looks dry, without shine, anemic.

A tight plug of mucus closes the entrance to the cervix. Deviation of the cervix to the side (left or right) usually occurs by 4-5 weeks of pregnancy.

Hormonal method

Studying the anterior pituitary and ovary by physiologists, a reaction to pregnancy was discovered. Three methods of detecting a reaction to hormones are used: Tsondeka and Ashheim, Call and Hart, Friedman and Schneider. It was proved that with the onset of pregnancy, the blood and urine of horses contains a huge amount of gonadotropic (FSH - follicle-stimulating and LH - luteinizing hormones), as well as gonadal (folliculin) hormone.

All of these hormones make sex hormones function.

Folliculin appears not only in the blood of equine horses, but also in cows and pigs. These methods of detecting the stage of pregnancy in mares, due to the quantitative content of hormones in the urine and blood of the studied animals, have the highest accuracy - from 95% to 100%. However, their practical use is essentially zero, since it is associated with the complexity of execution and expensive consumables. Typically, these methods are applied only at the level of research.

With the onset of the fourth month and almost until the very end of pregnancy, only the presence of the hormone folliculin is tested. A pregnant horse has a small amount of this hormone in its blood. Therefore, urine is taken for research. During this period, the folliculin content is huge, tens and even hundreds of thousands of “mouse units” in a liter of urine.

The presence of folliculin in the amount of only a few thousand “mouse units” in a liter of urine indicates that the mare is not pregnant or has a short gestation period. Therefore, the presence of pregnancy is judged by the difference in the availability of the amount of the hormone folliculin.

With the help of mare's urine, folliculin is detected, because the hormone in the urine is hundreds of times greater than its presence in the blood.

A method of preparing a solution for injection

First of all, you need to reduce the toxicity of urine. For this, the liquid is filtered off with paper cones, sedimented and the upper transparent layer is selected. Approximately 10-15 ml of the obtained liquid are acidified with acetic acid until a slightly acidic reaction (test by litmus strip) and ether is added in the same volume. The solution is shaken for five minutes, then stand for 10 minutes. The ether is drained, and the resulting liquid settles until complete weathering. Adding ether activates the hormone folliculin.

Next, dilution with distilled water to three volumes from the initial weight is carried out. And only after this urine is injected into castrated or immature female mice in the absence of estrus.

For injection, up to 4 mice are taken and the resulting solution is injected with it starting from 0.3 ml of whole urine and ending with 0.1 ml of urine diluted in half with distilled water. In later pregnancy, mares urine for injection to mice is diluted with water 2-3 times.

Sometimes the diagnosis is required to be clarified, then blood and urine are taken from each animal that is tested for foal, after appropriate preparation several mice are introduced, usually 3-4. When sex hormones are present in the test fluid, mice develop estrus, approximately 70-100 hours after the first injection.

Detection of estrus in mice is as follows. Starting from the hundredth hour, three times a day in mice, vaginal discharge is removed using a cotton swab and a platinum loop. A smear is prepared from the mucus by adding a drop of distilled water. The glass is dried, fixation is carried out with alcohol and stained according to Romanovsky.

Microscopic studies can be carried out without staining, but in this case, it is necessary to darken the viewing field. Up to three strokes can be applied to one glass slide. A continuous mass of keratinized epithelial cells indicates the presence of estrus in mice. In the absence of estrus, the smear shows white blood cells and nuclear epithelial cells.

Sometimes, to detect estrus, an autopsy of experimental rodents is performed. An enlarged and full-blooded uterus indicates the presence of estrus. An autopsy is also done in order to obtain additional confirmation of the presence of a prolan. Enlarged ovaries, mature follicles, red blood points instead of graaff vesicles, sometimes the corpus luteum indicates a positive result. Also attracted attention are increased in volume and mass and blood-filled vessels of the genitals.

There is the term "mouse unit." It means the minimum amount of pituitary or follicular hormone that can cause estrus in mice.

The method of detecting the reaction of Friedman and Schneider uses sexually mature rabbits up to 1200 g in weight. This method is preferable, as it reduces the waiting time from one hundred hours to 48. Experimental animals are seated in separate cells. Injections from the serum of the studied mare make 10 ml into the rabbit’s ear vein. After 48 hours, the abdominal wall is dissected and the ovaries are examined, according to which the mare's foal is determined.

Follicles are usually filled with blood or torn. In order to use the rabbit again after three weeks, the dissection is sutured. It is possible to use one animal up to five times. But keep in mind that with repeated use there is always a risk that the animal will experience anaphylactic shock associated with an immediate allergic reaction. Injection can be a powerful allergen.

Sometimes the abdominal wall dissection is replaced by examination of the ovary through an artificially created canal in the abdominal wall.

Ovarian transplantation is also practiced in castrated rabbits. The ovary is placed in the anterior chamber of the eye. Operations are not always successful, but with a positive outcome, after the end of the inflammatory process, the cornea brightens. Thus, it is possible to monitor the grafted ovary. The rabbits are injected into the ear vein and after three days an increase in the follicle is observed, after five - the appearance of the corpus luteum. There is hemorrhage in the transplanted ovary.

Method for detecting Call and Hart reactions

Starting from the 30th day of pregnancy, you can try to do a test for prolan. True, it may be inaccurate, because the content of prolan in the blood of the animal in this period is very small. Only 150 international units per liter of blood. Starting from the 42nd day, the amount of the hormone increases sharply, to about 30,000 international units per liter of blood, and by the 90th, 50,000 or more IU.

Therefore, this time period is the most suitable moment for the most accurate blood test for prolan. Fidelity of the result is almost at the level of 100%. Starting from the 4th month of the draw, the level of prolan in the blood is rapidly falling.

Up to 50 ml of blood is taken from the jugular vein from the jugular vein, serum is defended, and it is injected under the skin of three immature female mice weighing 6-8 g. Injections are made 3 days 2 times a day, injecting from 0.5 to 0.1 ml of serum.

After 4 days, smears were taken from experimental mice (each 2-3 times) and a microscopic examination was performed. The horse’s stiffness is confirmed by the fact that from the proline hormone contained in the injection, the experimental mouse is matured. This is revealed by the fact that the follicle matures, the hormone folliculin is formed and the estrus begins. A smear on a glass slide indicates the presence of scales, i.e. nuclear free cells. If the smear test has an unclear picture, then after a day, an autopsy is done on the mouse.

Stiffness is confirmed by an increase in the uterine horns, follicles filled with blood, mature follicles, and also yellow bodies are present in the ovary. In order to conclude about changes in the ovaries and uterus, several mice are opened.

All stages of pregnancy in mares are examined and confirmed by tests. This is the only way to organize proper care, maintenance and prepare the animal for childbirth.

Anatomical and physiological changes in the body of a pregnant mare

The absence of sexual hunting in a mare after covering it may be the first sign of her stubbornness. It causes certain anatomical and physiological changes in her entire body, they are especially noticeable in her genitals and udder. These changes occur under the influence of hormones secreted by the placenta (fetal membranes of the fetus) and the corpus luteum (a temporary gland formed during pregnancy in the female’s ovaries).

A pregnant horse becomes calmer, more careful while moving. She begins to eat more, in her body the digestibility and digestibility of feed improves, which leads to an increase in fatness. This is also due to the fact that a certain amount of protein, fat and glycogen is stored in her body in reserve. True, uterine fatness decreases before a foal. This is due to the fact that in the last stages of the draw, the fetus grows very quickly (in the last one and a half to two months it increases its weight by 2-3 times!). In order to ensure such rapid growth of the fetus, a lot of mineral substances are required, some of them are practically stretched from the bones and hooves of the horse, therefore it is especially important to provide the uterus with a complete diet.

From the body of a female foal, the fetus receives oxygen and nutrients through the blood, in connection with which the work of the heart and respiratory organs is enhanced, the blood volume increases by 20-30%. In the blood, the carbon dioxide content rises, resulting in a slight acidosis.

A pregnant female significantly increases the physiological load on the liver, because now she must neutralize the metabolic products of not only her body, but the fetus, as well as increased kidney function.

Stiffness is accompanied by a noticeable increase in the size of the uterus and a change in its location. The mass of the pregnant uterus increases by 5-20 times compared with the non-pregnant state. It moves into the abdominal cavity and is located on its side wall on the left and reaches the diaphragm. Crypts are formed on its mucous membrane, due to which the placenta is attached to its wall. The fibers of the uterine wall become 7-15 times longer and 5-6 times thicker. Despite this, its wall is still thinning. The blood vessels of the uterus thicken and lengthen, many new vessels appear in its wall, the volume of blood flowing to the organ becomes 4-6 times larger.

The canal in the cervix is ​​filled with a thick viscous secret, from which the so-called mucous plug of pregnancy is formed.

In the second half of the draw, the female’s abdomen increases in volume, in the lower region (to the left directly above the udder) in the morning, it is better after the animal drinks, you can notice how the fetus moves.

Thus, pregnancy is accompanied by a significant restructuring of the animal’s body that occurs in connection with the adaptation of its body to new conditions of existence. With proper feeding and maintenance of the pregnant mare, and if she is healthy, this restructuring of her body proceeds quite normally. If the pregnant mare is sick or the conditions in which she is not provided for the increased needs of her body, then the most serious consequences may occur: abortion, female disease, or even her death. Therefore, in this period of the mare’s life, her life and health, as well as the life and health of her fetus, are completely dependent on the person and his responsible attitude.

Duration of pregnancy in the mare

The duration of the draw is understood to mean the period from the fertilization of the horse to its birth.

Its duration depends on the breed, the number of fruits, their gender, the age of the female and the conditions of her feeding and maintenance. In animals of late-ripening breeds, the duration of pregnancy is somewhat lengthened; Under excellent conditions of keeping and feeding, its period is extended. She also lengthens during pregnancy with a stallion, but if a mare wears twins, then her pregnancy is shortened. In primiparous females, the period of draw is longer than in those giving birth repeatedly. In old animals, as well as in young ones, it is shorter than in full-aged mares. On average, mares' draws last 335 days (11 months), sometimes fluctuations from 310 to 370 days can be observed.

All owners need to know all the factors that can cause an abortion (abortion) in order to do everything possible to prevent them:

  • poor or poor-quality feeds,
  • sudden shocks, falls, bumps, injuries,
  • sharp whips, stresses,
  • fast driving, transportation,
  • overwork of the mare at work,
  • hypothermia when a horse consumes frozen, icy grass,
  • grazing during frosts, with their prolonged stay in the cold wind in cold wet weather,
  • lack of protein, minerals and vitamins in the diet.

Feeding, keeping and using a pregnant mare, and care for it

During pregnancy, the animal is in high physiological stress, therefore, full feeding, proper maintenance and use, good care of it are very important and often determining conditions for the normal course of pregnancy, maintaining the health of the mare, good development of the fetus, a good termination of childbirth and the birth of a healthy offspring .

The general requirements for feeding a pregnant uterus are as follows:

  1. Her nutrition should fully ensure the need of her body for nutrients, it should contain a sufficient amount of proteins, sugars, minerals and vitamins.
  2. The feed included in the diet should be well eaten and necessarily benign.
  3. Rotten, sprouted, moldy, frozen, and poisonous feeds are excluded.
  4. It is necessary to provide pregnant females with lick salt.
  5. In the summer, it is better to keep the mare in the pasture, as fresh air, sun, fresh grass, and the animal's laid-back movements have a beneficial effect on her health and contribute to the normal development of the fetus. The pastures that are of the highest quality in terms of grass stand and water sources, free of snags and pits, are set for them, the grazing time and the watering time are established, where necessary, they feed the females with green and concentrated feeds.
  6. In the autumn period, when the time for grazing is reduced, it is necessary to strengthen the diet in a timely manner so that pregnant animals do not starve and lose fatness.
  7. When stalling animals should receive better quality hay, silage, root tubers, and concentrated feed.
  8. In the winter-stall period, special attention should be paid to the usefulness of rations for vitamins (especially carotene) and calcium and phosphorus salts, and if not enough, include vitamins rich in foods (green feed, silage), add fish oil, bone meal, chalk . For prophylactic purposes, injected into the feed or put intramuscularly concentrated vitamin preparations.
  9. It is necessary to provide free access to quality drinking water.

In addition to providing good nutrition, it is necessary to fulfill the following conditions for the content and use of it during the draw:

In the stall period, mares must be placed in comfortable, dry rooms with plenty of light and good ventilation.

The premises and the animals themselves must be kept clean and provided with a clean, dry litter.

In the spring after pasturing the animals in the pasture and in the autumn before setting them up for winter-stable maintenance, the premises are thoroughly cleaned, disinfected and whitewashed to prevent infectious diseases.

For pregnant females during the stall period with machine-tool maintenance, daily exercise is necessary, but it is better to keep them free in levada to avoid the development of edema and postpartum complications.

Mares with a six-month pregnancy are exempted from hard work, and two months before the foal and two weeks after it they are exempted from all work.

Causes of onset and signs of approaching childbirth

Childbirth is a physiological process during which a mature living fetus is excreted from the mother’s body into the external environment and fetal membranes and water are released. Childbirth occurs at the end of pregnancy. They arise as a result of contraction of the muscles of the uterus and abdominals.

There are several theories that explain the causes of labor. The authors of one theory believe that childbirth occurs from irritation of the nerve ganglia of the uterus by a growing fetus. According to another theory, childbirth occurs as a result of the fetus releasing special substances that cause contractions and attempts. The authors of the third theory explain the appearance of childbirth by the excessive release of hormones of the posterior pituitary and adrenal glands at the end of pregnancy, which excite uterine contractions.

According to the neurohumoral theory, childbirth appears as a result of exposure to the body of a pregnant female by a number of factors. Thus, childbirth is a complex interconnected neurohumoral process that occurs under the influence of a whole range of causes that act against a certain background of the state of the nervous system.

Before giving birth, a pregnant mare shows signs, or precursors, of an approaching birth. These signs include a whole range of changes. So, for example, two weeks before giving birth, an ever-increasing relaxation of the pelvic ligaments begins as a result of soaking them with serous fluid, the sacrum begins to sink, the loop swells and relaxes. Then a moderate physiological edema of the udder develops - it increases in volume, becomes rounded, the nipples become swollen, elastic and directed to the sides. A few days before birth, colostrum appears, which appears in the form of drops on the tips of the nipples. Before birth, the expiration of mucus from the vagina begins due to the thinning of the “plug” of pregnancy. With insufficient exercise in the horse, the abdomen, hips and legs may swell.

Immediately before the foal, she begins to worry: she periodically lays down and gets up again, looks back at her stomach, often moves from one leg to the other and refuses to feed. Childbirth most often begins at night. The latter is explained by the fact that the number and strength of environmental stimuli at night decreases and therefore the tone of the cerebral cortex decreases.

Under these conditions, impulses coming from the uterus become able to excite the subcortical centers of the brain, which, acting on the uterus, cause rhythmic contractions of its muscle layers.

Before giving birth, the horse's body temperature decreases slightly, and the bladder and rectum are freed from the contents.

During childbirth, the mare lies down and stretches its legs. Then begins the contraction of the uterus muscles - contractions, which normally occur again and again after 2-3 minutes and their duration is from half a minute to one and a half minutes. As a result of contractions from the birth canal of the female, a bubble appears, consisting of the choroid and the outer sheet of allantois. It bursts and urine fluid pours out. Immediately after this, strong attempts begin, and a second bubble leaves the birth canal. He immediately bursts, and from the birth canal the elongated legs of the foal are shown with their head lying on them. If the foal goes backwards, the hind legs are shown first. However, this position of the fetus is rare. Usually, the fetus is rapidly excreted from the birth canal. The entire process of childbirth in a horse lasts an average of 20-40 minutes.

Sometimes the shell of the water bladder does not burst, and the mare’s fetus is born in the amniotic fluid, as they say “in a shirt”. In this case, the mare herself tears the shell with her teeth, or the person who is present during childbirth does this.

The horse’s placenta leaves within 5-30 minutes after the birth of the foal, and sometimes almost simultaneously with it.

Help the mare with normal birth

When there are signs of an approaching birth, the pregnant horse is separated from the herd and transferred to the stall, where 24-hour duty is established to provide obstetric care in a timely manner.

The following materials should be prepared in the maternity ward: 2-3 obstetric loops (you can use thin ropes 1-2 cm thick and 2-3 meters long instead), threads for bandaging the umbilical cord, scissors, a towel, a bottle with an alcohol solution of iodine and any disinfectant (e.g. soap alcohol).

In the event of contractions, in no case should you bother the mother in childbirth, since too early intervention in the birth process, as well as late obstetric care, only bring harm.

If childbirth is delayed, you need to conduct a study through the vagina with a cleanly washed and disinfected hand. If during the study it is established that the cervix is ​​not fully opened, you need to remove your hand and wait a while until the fetal bladder comes out.

Fetal bubbles emerging from the birth canal, as a rule, burst themselves. If this does not happen, the fetal vesicles must be broken by hands, but this should only be done when they hang from the birth canal and the limbs of the fetus can be felt through them.

After the fetal membranes have torn and amniotic fluid has departed, strong contractions and attempts appear, under the influence of which the fetus begins to move outward. If the fetus moves too slowly or does not advance at all, resort to obstetric care. To do this, they take the fetus with their hands for the extremities that appear from the birth canal, and slowly pulling at the time of the attempt, they help to remove it. Excretion should be accelerated as much as possible if the fetus leaves the hind limbs.

In order to avoid rupture of the upper commissure of the labia, they are captured in the upper part by hand and collected in a crease.

After childbirth, the placenta hanging from the birth canal is forbidden to be pulled or torn off. If it is very long and hangs to the floor, then it is tied with a knot. Then they are on duty near the horse until the placenta leaves. After it is cleaned in a special container, and then disposed of.

The puerperas are rubbed back of the body, washed with a disinfectant solution of her labia, hind limbs and udder. In the machine where the birth took place, the litter is replaced.

Simple rules for taking newborns

As soon as the newborn has left the birth canal, his mouth and nose are first freed from mucus, wiping them with a clean towel. Then, when the newborn has respiratory movements, they begin to process the umbilical cord. In no case can you break off the umbilical cord of a foal due to the peculiarities in the structure of their navel. It must be tied with a thread at a distance of about 10 cm from the abdominal wall and cut off, and the stump of the umbilical cord should be greased liberally with a disinfectant solution.

After this, the newborn is laid on the mother for licking. She, licking the remains of amniotic fluid from the newborn, massages his entire body with his tongue. In addition, licking is also beneficial for the woman in labor, since she also experiences reflex excitation of uterine contractions, which helps to accelerate spontaneous separation of the placenta and normal genital involution.

A normally developed foal is mainly found by the mother’s nipples soon after birth, but sometimes a person should help him. A couple of hours after the foaming, the mare should be drunk with warm water and give her some good hay. The foal is left with her, but it is ensured that he completely sucks the colostrum out of the udder, because it helps the foal's body to function and develop properly.

Compliance with all the recommended rules will help to maintain the mare's health and get a healthy offspring.

Case

At about 1.5 years old, the mare becomes sexually mature. However, at this age, it is not yet sufficiently developed for the draw to pass without complications and a normal foal to be born. The physiological maturity of the body in a mare occurs at the age of 3-4 years. Therefore, the first mating of a mare is carried out when it reaches the physiological maturity of the body - i.e. at the age of 3-4 years.

Owners of horses who want to receive a full-fledged offspring from their mares for mating horses need to be assigned the period from March-April to mid-July. In regions with severe climatic conditions, in order to avoid the occurrence of catarrhal diseases in the animal, the beginning and end of the random period are shifted two weeks forward.

In horses, several methods of mating (mating) are used:

1. Manual pairing - carry out an individual selection of mares and stallions, sexual intercourse proceeds under the direct control and supervision of horse owners. This type of mating allows you to keep an accurate record of inseminations, regulate the sexual load, and carry out an examination by a veterinarian.

One stallion is assigned 40-50 mares. Only healthy animals are allowed to mate. Before coitus, the external genitalia are washed with warm water, the tail of the mare is bandaged with a clean bandage and taken aside to prevent the stallion's penis from being injured by hair. The mare must have uninhibited hind legs. To avoid injury to the stallion, a random harness is put on their neck. The penis and preputial sac of the stallion are washed with warm water and wiped with sterile wipes. Mating is carried out in a quiet, relaxed atmosphere. The first stallion coitus is allowed on the second day (evening) after revealing the mare's hunt and is repeated until the end of the hull after 48 hours, and in the presence of a pronounced hunt - after 24-36 hours.

2. Cooking mating. The mares, scheduled for insemination, are led into a spacious fence (brews, bases) and a stallion is released to them, who himself chooses the queens in the hunt and inseminates them without the intervention of the caring staff. Mares and stallions should be relaxed. The load on the manufacturer is the same as with manual pairing. The stallions are kept separately from the mares and released into the brew for 1-2 hours in the morning and evening.

3. Mating used in herd horse breeding. The stallions of the producer are kept round the clock with the mares in the pasture under the supervision of the herder, which records the insemination of the queens. In this case, coitus is carried out by the manufacturer without human assistance. 20-35 mares are assigned to one adult stallion, 12-20 mares to the young, 12-15 mares to the old.

Hunting mares

With the onset of puberty, mare hunting appears on average every 20 to 21 days. If the stallion and the mares are kept in one herd, then the approach of the mare's hunting is judged by the way the stallions behave. If the mare has a hunt, the stallion begins to actively groom her, smell her under the tail, gently pinch her neck. When neighing a stallion, the mare in a hunt worries, raises its head, “spins its ears”, turns to the side of the sound, responds with neighing, raises its tail, spreads its hind limbs, makes rhythmic contractions of the labia, excrets urine in small portions.

In the case when the mare and the stallion are kept separately, it is necessary to monitor the behavior of the mare. The presence of a hunting mare is indicated by the following symptoms:

  • Frequent urination appears.
  • The mare raises its tail.
  • Spreads hind legs wide.
  • From the genital gap there is an abundant secretion of mucus (estrus).

Hunting at the mare lasts from 2 to 12 days. In most cases, young mares are 4–5, suckers (middle-aged) 5–7, and old, many foals mare for 7–12 days. During the cage, the mare stands calmly.

Changes in the mare's body during pregnancy

In pregnant mares, with the development of the fetus, intraperitoneal pressure rises, which in turn leads to an increase in bowel movements and urination, breathing becomes more and more chest and rapid. Increased kidney activity. In the second half of pregnancy, protein is often found in the urine. An increase in the load on the cardiovascular system causes hypertrophy of the heart muscle, mainly the left ventricle (pregnant hypertrophy), the functional state of the myocardium and vascular tone increase. As a result of the development of placental circulation, the vessels of the uterus grow, their diameter increases by 4-5 times. The amount of blood increases by 20-25%, but its morphological composition is almost unchanged. Young forms of red blood cells appear in the blood. Fluctuations in hemoglobin in the blood remain within normal limits. There is an increase in blood coagulability. The reaction of erythrocyte sedimentation is accelerated. The amount of calcium and phosphorus in the blood decreases, potassium - increases. There is a physiological "pregnant acidosis". The amount of total protein and the viscosity of blood serum are slightly reduced.The content of calcium, phosphorus (calcium - phosphorus coefficient), carotene, alkaline reserve of blood varies depending on the season of the year and the composition of the diet.

There is a strong change in metabolism. Initially, as a result of increased appetite and digestibility of feeds, nutrition improves, by the end of pregnancy, mares lose weight, and if not properly fed and kept, they may be depleted.

Often in mares there is a violation of mineral metabolism. In the absence of mineral nutrition in the diet, the mare's bone tissue is depleted in calcium salts, which predisposes to spontaneous bone fractures. Violation of mineral metabolism greatly affects the condition of the teeth. In close connection with mineral metabolism is water exchange. Studies have shown that tissues during mares' pregnancy retain water, become more juicy, and are prone to edema. Pregnancy in a mare is accompanied by the accumulation of nitrogenous substances in the body. Urine contains less urea, the amount of ammonia and other products of incomplete combustion of proteins increases. The absorption of carbohydrate feed is improved. Glycogen accumulates in the liver. Changes in fat metabolism are expressed in an increase in the amount of neutral fats, lipoids and cholesterol in the blood. During pregnancy, hormones (planental) are formed and accumulate in a significant amount in the body. In pregnant mares, melanogormone is formed, which causes pigmentation of the placenta, the appearance of "pregnancy spots" visible on unpigmented skin, especially in the mammary gland.

Mare embryo and fetus development

At the age of 1 month, the body length at the embryo is 0.5-0.7 cm. The head does not have the shape characteristic of a horse.

At 2 months, the body length is 5.5-7cm, weight 62-70g. The head becomes shaped and takes the shape of a horse. A hoof configuration appears on the limbs.

At 3 months, the body length is 12-15 cm. Short ears are clearly visible. Nipples are visible on the mammary gland, hooves are well defined. The deposition of salts in the bone tissue begins.

At 4 months, the body length is 20-30 cm, weight 1300-1600 g. The appearance of the external genital organs. Sometimes separate short hairs appear on the lips.

At 5 months, the body length is 30-37cm, weight 3-4.5kg. Thick hair on the lips ("mustache" and "beard"). Separate hairs appear on the skin of the superciliary process and on the tip of the tail. The external genitalia are well decorated. Scrotum and preputial sac weakly expressed.

At 6 months, the body length is 40-75 cm, weight 4-6 kg. Thick hair on the lips, well-defined eyebrows. There are separate hairs on the tail, eyelashes appear, separate hairs are visible on the neck (mane) and on the skin of the apex of the auricle.

At 7 months, the length is 45-48cm, weight 4.5-7.5kg. Mane hair is well defined. The skin of the auricle is covered with hair.

In 8 months, the length is 50-90cm, weight is 9-15kg. Hair appears on the skin of the entire head. The ears, mane and back are covered with thick hair. Separate hairs along the spine on the sides are noticeable. The tail is covered with hair.

At 9 months, length 60-115cm, weight 12-20kg. All skin of the body is covered with hair. Well-defined hair on the skin of the corolla. The tail is well overgrown with hair.

At 10 months, the length is 80-125cm, weight is 18-30kg. The whole body is covered with short hair. On the soles of the hooves a significant outgrowth of the horn is found.

At 11 months, the fetus becomes ripe. The length of the fetus is 1-1.5 m, weight 26-60 kg (1/14 -1/16 of the weight of the mare before childbirth). The entire surface of the body is covered with thick hair. Testes often fall into the scrotum. Incisors and fangs protrude on the upper and lower jaws. Three dairy premolars protrude from each side on the upper and lower jaw.

Determination of draw

Ultrasound is used to diagnose draws in the early stages, they are tested in a veterinary laboratory. When determining pregnancy, apply external diagnostic method consisting in the fact that when examining a mare in the second half of pregnancy, a protrusion of the left abdominal wall is noticeable, and at the end of bearing, its lower part sags. After posting, you can observe the startle of certain sections of the left abdominal wall of the mare, due to the movements of the fetus. A veterinarian can listen to the fetal heartbeat by auscultation.

Vaginal diagnostic method consisting in the introduction into the vagina of the hand and palpation of the fetus, as well as by introducing into the vagina a vaginal mirror (examination of the condition of the mucous membrane and finding thickened sticky mucus).

Rectal diagnostic method. It is convenient to carry out a massive summer-autumn check of mares for a lottery by evening or at lunchtime immediately after the horses return from work. When conducting a rectal examination, both hind limbs should be put in place or used for this reins. In mares, they raise their heads, and in strict mares, their left forelimb. In a rectal examination in 20-27 days of pregnancy, a change in its horns characteristic of the pregnant uterus is already established. The horns of the uterus become elastic, rounded, sausage-shaped. At 2 months, the horn of the fetus and uterine body is enlarged, rounded, upon palpation we find a bubble the size of the head of a newborn baby.

The desire to establish the gestational age in the second half with an accuracy of 1-2 weeks is often in vain, since errors of 2-3 months are quite acceptable.

In addition, there are a number of signs suggesting that the mare is foal. These signs are usually attributed to:

  • Increased appetite.
  • A mare after insemination does not come to the hunt.
  • The horse sleeps more.
  • With a long gestation period, he spends most of his time lying down.
  • In the herd, the mare seek to stay away from other horses.
  • A few days before the ridge, the udder increases.

Caring for a horse during pregnancy.

During mare's pregnancy, owners of LPH and peasant farms should carefully monitor the mare's diet. Pregnancy makes additional demands on the diet, the last three months of pregnancy, the nutritional value of the diet must be increased by 40%, compared with the first months of pregnancy. A mare-fed diet should be balanced for essential nutrients, as well as vitamins and minerals. Serving size decreases, and the number of meals, on the contrary, increases, since a pregnant mare cannot eat large portions of food. During pregnancy, its owners should not:

  • Do not load the horse heavily, refrain from its use in adverse weather conditions.
  • You can not shout at the foal mare, let alone beat and push it, as well as make any sharp movements.
  • It is strictly forbidden to feed a horse caked, moldy, frozen, musty feeds, as well as straw covered with fungus or rust (stachybotriotoxicosis in animals, fusariotoxicosis in animals).
  • It is forbidden to drink the mare cold water, as this may lead her to an abortion.
  • You cannot drive a mare to street ponds if there is ice on the street. traumatic abortion is possible as a result of the fall (symptomatic non-contagious abortion).
  • The premises for keeping the mare's foal should be very warm, there should be no drafts, with a sufficient amount of dry and soft litter.
  • In order to prevent edema, instead of normal work, provide the horse with daily light walks.

Childbirth at the horse

Childbirth in a mare is a physiological process consisting in the removal of a mature live fetus from the body of a mare with the expulsion of the membranes and the fetal waters. Childbirth is carried out by active contractions of the muscles of the uterus and the abdominal press, with the participation of the entire body of the mare and partly the fetus.

Harbingers of Childbirth

As the end of fruiting approaches, the mare's body undergoes a series of changes, the significance of which is its adaptation to the implementation of the birth act.

The precursors of childbirth include:

  1. The transformation of a mare’s usual pelvis into a “maternal” one, expressed in the relaxation of its ligamentous apparatus. All ligaments of the pelvis become loose, their length increases by 1/3 or ¼. Usually the sciatic - sacral ligament, when pressed in the area of ​​the sub-caudal fold, is felt in the form of a dense stiff cord. If you grab this ligament with your fingers before delivery and pull it to the side, it moves easily, sometimes its contours are smoothed so much that it is not palpable. The indentation between the base of the tail and the sciatic tubercle increases (“lowering of the sacrum”). Typically, the pelvis becomes “generic” 12-36 hours before the onset of the fetus.
  2. Enlarged and swollen labia, their skin becomes smooth, folds straighten.
  3. Thinning before delivery of thick, sticky vaginal mucus. The mucous plug that closes the cervical canal dissolves and stands out in the form of “leashes”, which are viscous strands of transparent mucus hanging from the external genitalia. Vaginal mucus thinning and “leashes” are observed 1-2 days before delivery.
  4. Isolation of colostrum is usually 2–3 days before delivery, but may be earlier, during, or only after delivery.
  5. A decrease in body temperature by 0.4 -1.2 degrees for 12-50 hours before childbirth with its tendency to increase during the last month of pregnancy.
  6. Shortening the cervix in the mare after 12-24 hours.

Before giving birth, the mare behaves uneasily and excitedly, is constantly on the move, refuses to take food, and perspiration is observed.

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