Knowing how long a cow is pregnant is essential for every farmer. This is necessary primarily in order to properly plan the care of the animal and provide it with the most comfortable conditions necessary for the correct formation and development of the fetus. In addition, knowing the exact time of calving, the owner of the cow will be able to organize her dry period in time and correctly receive the calf.
How long does a cow walk pregnant?
There is no definite answer to the question of how long a cow's pregnancy lasts. This is influenced by many different factors, including the size of the fetus, the correct care for the animal, and the type of diet. So, if a cow receives a meager food and an acute deficiency of vitamins and minerals is observed in her body, then the duration of gestation can be noticeably reduced. The same happens when the fetus is too large and the animal is under stress. If everything is in order with the animal, then the duration of gestation will be on average 285 days.
At the same time, up to 6% of premature calving falls on about 240 days.
If calving occurs on a period of 140 days or less, then it qualifies as a miscarriage, and the fetus is born unviable. This can happen as a result of incorrect rectal and manual examination, diseases of the reproductive organs, ultrasound examination of the fetus at a gestation period of up to one month, as well as due to excessive physical exertion that occurs when the animal is driven to distant pastures. A no less common factor is hormonal surges, provoked by a sharp change in the weather, or the effect of drugs that are contraindicated for pregnant cows.
However, it is not uncommon for an animal, on the contrary, to walk and bear a calf up to 311 days. Long-term gestation is typical for 10% of animals and is not a pathology. Reaching, as well as early calving, occurs for a number of reasons, the most common of which are hormonal disturbances in the cow's body. Another reason is the slow formation of the fetus, due to the individual characteristics of the female.
If all calving deadlines are long over, and the cow has been carrying a calf for more than 311 days, then she needs urgent veterinary assistance.
Definition of pregnancy
It is quite problematic to determine the pregnancy of a cow in the early stages, however, an experienced farmer can do it. There are both physiological and behavioral signs by which pregnancy can be recognized for up to 1 month:
- a pregnant cow becomes much calmer and more careful;
- literally from the first weeks of pregnancy, there is a noticeable improvement in appetite;
- the animal's hair becomes smooth and shiny, begins to look very well-groomed;
- vaginal discharge appears in the form of transparent mucus;
- the hunting state disappears.
If the term of the alleged pregnancy exceeds one month, then the ways to diagnose it will be completely different.
- One of the most reliable methods for determining pregnancy at home is the following: expressed milk is dropped from a pipette into a glass of plain water and the result is monitored. If the cow is pregnant, then the drop of milk will completely dissolve in the water, and if not, then the milk will spread over the surface of the water in a whitish cloud.
- A teaspoon of alcohol is mixed with the same amount of expressed milk and stirred. If after five minutes the milk begins to curdle, then the cow is pregnant.
- Rectal examination is carried out 2-3 months after mating and allows you to know for sure the state of the uterus. This procedure can only be performed by a veterinarian who has considerable experience in carrying out such manipulations and will not harm the animal. To do this, he will need the help of the cow owner, since the procedure is quite unpleasant and the cow can react aggressively to it. It should be noted here that the rectal examination should be carried out strictly in the morning after the bowel movement has occurred. During the examination, the heifer should lie on its side or stand.
Especially active cows, who cannot tolerate any manipulation, must be tied by the horns and fixed in the pelvic region. Before the examination, the veterinarian disinfects the hands and puts on protective gloves. In order for the animal to be caused as little inconvenience as possible, they are abundantly lubricated with petroleum jelly. Then, with gentle movements through the rectum, the specialist palpates the uterus, and determines the presence and duration of pregnancy.
The advantage of rectal examination is the fact that it allows you to detect pathological processes not only of the uterus, but also of the ovaries, organs of the digestive system and urinary tract.
- You can also check the cow for pregnancy using an ultrasound scan. The study is carried out in the second month of the alleged pregnancy. It allows early diagnosis of abnormalities in fetal development and dysfunction of the cow's reproductive organs. The examination is carried out by a veterinarian using a portable portable device with a visit to the house.
- You can also donate your cow's milk to a veterinary laboratory where it will be tested for pregnancy. It is recommended to do this on the 12th day after mating.
- The visual method of determining pregnancy can be used towards the end of the fourth month. During this period, the cow's belly becomes noticeable and the sides are rounded, so even inexperienced farmers can understand that the cow is pregnant. From about this time, the fetus begins to move, which is especially well felt under the peritoneum, a little further than the costal arch and 40 cm below the hungry fossa.
How to find out the date of calving?
In order to calculate the calving date as accurately as possible, it is advisable to know the mating time. Using a simple formula will help in this: D = (H + 11) / (M-Z), where D is the date of calving, H is the date of coverage, and M is the numbering of the month. For example, mating took place on April 17, where April is the fourth month of the calendar. So, the calculation will look like this: D = (17 + 11) / (4-3), which in the end will look like 01/28. In other words, if insemination took place on April 1, then the cow will calve on January 28 of the next year. If, when adding the numbers in the first parenthesis, it turned out more than 30, then 30 is subtracted from this amount, and 1 is added to the ordinal number of the month.
For example, if the cow was covered on May 24, then 24 + 10 = 34 - and since the 34th does not exist, then we subtract 30 from it and get 4, only the month will not be January (4-3 = 1), but February, since we added one to it. The same with the second parenthesis: if the heifer was covered in January, February or March, add the number 12 to the received negative number or zero (for March). However, as mentioned above, these calculations are only approximate values, and the calving time they cannot determine with an accuracy of one day.
After the cow's pregnancy has been confirmed and the calving date has been calculated, it is advisable to start a pregnancy calendar. This will allow you not to miss the deadline for transferring the animal to dead wood and its launch, as well as to agree in advance with the veterinarian and purchase everything you need to take delivery.
How long can you walk?
The problem of overstepping the calving dates worries many farmers. It is more accurate to determine how long a cow has been carrying a calf, using entries in the pregnancy diary. With a short period of walking of 10-15 days, you should not worry, since these two weeks may be nothing more than an error in determining the day of conception of the fetus. If the period of crossing is too long and has exceeded 20 days, an urgent need to consult a veterinarian. Only an experienced specialist will be able to determine the reason for the delay in calving and, if necessary, provide qualified assistance. This is a rather serious matter and in no case should it be allowed to take its course. The reason may lie in freezing and even mummification of the fetus, which will require immediate surgical intervention.
In the first two-thirds of pregnancy, the cow only needs good nutrition and no stress, while in the last trimester she needs to create special conditions. Approximately 60–70 days before calving, the heifer is transferred to dead wood, in other words, milk is stopped. This is necessary in order for the animal to rest before giving birth and feeding the calf, and to gain enough strength for lactation. After the cessation of milking, an intensive accumulation of nutrients occurs in the cow's body, which she needs to fully feed the baby.
The transfer to dead wood allows you to preserve the health of the heifer, not to lose milk yield in the future and contribute to the birth of a strong and healthy calf. In no case should you reduce the dry period . So, reducing it to 45 days, you can get in the future a significant reduction in milk yield and deterioration in milk quality.
It will not have the required amount of not only fats, but also protein, which will immediately affect its beneficial properties.
The termination of milking is carried out gradually, as a sharp reduction can lead to udder mastitis. First, the cow is milked twice a day, then gradually they switch to one-time milking, and only after that they make a test single break every three to five days. After a pause, the udder is examined and, after making sure that there are no pathologies, the milking continues smoothly. In this case, nature itself often comes to the rescue, because when the milking regime changes, the cow's nervous system reacts by reducing milk yield and allows the animal to quickly adapt to new conditions. After 1–2 weeks, milk itself will stop arriving, which is a signal that it is time for the cow to switch to a special diet.
Power on startup
The change in the diet will be carried out gradually and within a week the cow is completely transferred to the new menu. Simultaneously with this, the water consumption of the cow is reduced, and the exception of concentrated and green feed is made from its daily ration. From this moment until the birth comes, the cow should be in a special position: walk more in the fresh air and consume a large amount of vitamins.
The walks should be long, but not tiring - exactly such that the animal can lie down and rest at any time. During the stay in the fresh air, the blood of the cow is actively enriched with oxygen and circulates better throughout the body. In addition, walking helps to improve muscle condition and strengthen the vestibular apparatus.
When kept in stalls, flaxseed cake, wheat bran and oatmeal are added to the diet of the cow, and the basis of the diet is roughage and hay. At this point, it is very important not to allow the animal to become obese or, on the contrary, underweight. At this stage, the main thing is to properly balance the diet and add nutrients in a strictly required dosage. So, for every 100 kg of weight of a cow, there should be no more than 210 grams of protein, 350 g of fiber, 540 mg of carotene, 95 g of calcium, 10 g of table salt and chalk, 48 g of phosphorus.
The last couple of months before calving are especially important. During this period, the fetus begins to actively grow in the womb and is rapidly gaining weight. Lack of essential minerals can lead to anomalies in its development and entail the birth of a weakened and sick calf. In addition, drafts should not be allowed in the room where the cow stays. This is especially true in the last months of pregnancy, when the threat of mastitis increases significantly.
If we consider the obligatory diet of pregnant cows of meat breeds weighing 500 kg, then it includes hay of cereals and legumes in the amount of 4 kg, corn silage - 12 kg, 4 kg of juicy haylage and 50 g of table salt. To the main "dishes" must be added 700 g of carotene, protein and starch, as well as 100 grams of minerals containing calcium, copper, cobalt and phosphorus, and 500 mg of zinc.
Dairy breeds during pregnancy are fed slightly differently than meat breeds: up to 7 kg of their diet is hay and haylage, up to 2.5 kg - dry feed, up to 12 kg - silage. Table salt should be present in the amount of 70 g. Dairy cows should be given more protein, starch, carotene and mineral supplements. Water consumption should be limited to 48 liters per day, and feeding should be done 3 times a day.
Both dairy and beef breeds are not offered pulp, stillage and yeast food additives, and they are also limited in food that contributes to increased gas production. Conversely, it is very useful to include in the diet 700 g of sunflower oil cake, 1.5 kg of wheat bran, 100 g of feed precipitate and 1 kg of pine flour. To simplify control over the nutrition of a pregnant cow in the pregnancy calendar, you can draw up a table in which you can enter what and how much the cow needs at each stage of pregnancy.
All food offered to pregnant cows must be of high quality: the use of moldy haylage or frozen silage is not allowed. Otherwise, the animal can significantly undermine its health, right up to the onset of premature birth.
It is also not allowed to deliberately reduce nutritional norms in the hope of facilitating calving. This will in no way simplify childbirth, but it will significantly weaken the pregnant cow.
Meals before calving
This final stage of a cow's pregnancy is very important and represents a kind of preparation of the animal's body for calving. Approximately 2 weeks before the expected date, the cow is fed exclusively high-quality hay made from cereals.
While concentrated feed is either completely eliminated or continues to be given, but not more than 1 kg per day. Also, juicy types of feed are removed, giving excess fluid, which is already quite a lot in the body of a pregnant cow.
The daily cumulative portion of food during this period should be about 10 kg. If you cannot give such an amount of feed, then you can feed it a little less, however, in this case, it is necessary to add vitamin preparations and 30-50 g of chalk and salt to the food. The cow is fed and watered before calving three times a day, and only filtered or boiled water with a temperature of + 8-10 degrees is used as a drink.
Changes in the body of a cow during pregnancy
As mentioned above, cow behavior changes almost immediately after insemination. The animal loses interest in the opposite sex, becomes very careful and lean on food. Then the behavior of the heifer stabilizes and is no different. Visible changes occur only a couple of months before calving. During this period, the cow becomes very vulnerable and begins to experience animal fear, so the owner needs to create comfortable conditions for the cow and protect it from stress and anxiety.
This is due to the fact that the cow becomes so fearful that any incident that she would not have paid attention to before causes her severe stress. This condition negatively affects the development of the fetus and, in some cases, can provoke a miscarriage. If the pregnancy of a cow takes place in winter, then it is taken to the corral for only 3-4 hours, the rest of the time the animal should spend in warmth and comfort.
In addition to behavior, its physiological characteristics also change. So, by the time of calving, the animal is gaining up to 50 kg and looks very plump. 14 days before giving birth, the belly of the cow is pulled down, and the udder increases. About a week before the birth of the calf, a sweetish secret begins to stand out from the udder of the cow. In sync with the secretions, the muscle ligaments that connect the bones of the tail and pelvis become soft and relaxed. About 24 hours before calving, an intense rush of colostrum to the teats begins, at the same time as the cow becomes very restless and alert.
These signs serve as a signal that childbirth will begin soon and require full combat readiness from the owner.
The most common problem associated with a cow's pregnancy is false pregnancy. Such an anomaly can occur for several reasons, and the main among them is hormonal disruption. An equally common mistake is the wrong mating date. As a result, the hormones prolactin and progesterone are in a disturbed state, the egg is not fertilized due to the lack of ovulation, and pregnancy does not occur. However, the body does not immediately understand the catch and continues to actively prepare for childbirth. Another reason for pseudo-pregnancy is disruption of the endocrine glands, especially the thyroid gland, as well as emotional turmoil and the lack of uniform production of sex enzymes.
Symptomatic abortion is the next major problem in cow pregnancy. This can happen for a number of reasons, the most common of which is fetal pathology. This often happens due to the close relationship between the female and the male, as a result of which the fetus undergoes mutation and is rejected by the body. This miscarriage is called idiopathic.
The defeat of a pregnant cow with parasites also often causes a miscarriage. The infection quickly infects the fetus and triggers an abortion. If such a nuisance happens to one of the cows, then it is recommended to disinfect the entire barn. Miscarriage can also be provoked by incorrectly accepted previous childbirth, as a result of which the muscular layer of the uterus has lost its former firmness and elasticity and rejects the fetus in the fourth and fifth months of pregnancy.
The next reason is stale or spoiled food, as well as poor immunity. Miscarriage often occurs due to too small or large weight of the animal, as well as as a result of a lack of minerals and vitamins. For example, a lack of vitamin E in food can provoke a miscarriage at 5-7 months.
How many times a year can a cow walk pregnant?
This question entirely depends on how much milk yield the owner of the cow planned to receive. On average, lactation lasts 6–7 months after parturition, with greater intensity in the second, third and fourth months. However, in this matter, everything is purely individual, and the longest lactation lasted more than two years after the birth of the calf. In the general herd, cows are usually kept up to five years of age, while the period of reproductiveness lasts until the onset of 12-15 years.
Thus, determining the approximate calving date helps cow owners to carefully prepare for the birth of a calf, not to lose milk yield and keep the cow healthy.
Determination of cow pregnancy is in the next video.