The corpus luteum in cows often leads to infertility. It happens that after insemination, pregnancy does not occur, the cow remains barren. In this case, it is necessary to establish the exact cause of the pathology, otherwise the animal may remain sterile.
What is the corpus luteum
Before carrying out artificial insemination, a favorable time is chosen - the period when the female is hunting and the formation of the follicle occurs. At a certain point, the follicle matures and the egg is released. When it reaches one of the uterine horns, the egg is fertilized. At the site of the rupture of the follicle, a certain cavity appears, which subsequently becomes overgrown with blood vessels. Further, it turns into a temporary endocrine gland - the corpus luteum.
After fertilization, the iron begins to produce biologically active substances that contribute to the development of pregnancy and fetal growth:
- steroids (progesterone, estrogen);
- peptides (oxytocin, relaxin);
- growth factors.
Progesterone and inhibin - sex hormones that have a positive effect on reproductive function.
Peptides - amino acids that regulate all physiological processes.
Cytokines - biological molecules capable of coordinating the work of the immune, endocrine and nervous systems.
The gland continues to work in cows throughout pregnancy, until the calf is born.
In the event that fertilization did not occur, the formed corpus luteum does not have further development, it gradually disappears. After the next sexual cycle, when the individual is again hunting, the formation of a new follicle begins.
Reasons for the formation of a corpus luteum
The corpus luteum sometimes, for various reasons, can linger in the ovary, because the action of hormones does not allow the follicle to mature and release the egg. Although ovulation has occurred, for some reason the egg does not enter the uterus. In such cases, experts declare the persistence of the corpus luteum.
The corpus luteum is formed, works, regresses with the interaction of the pituitary gland, ovary, and the immune system. With pathology, a failure occurs in the entire hormonal system.
The main reason for the formation of a corpus luteum, which veterinarians claim is maternity paresis.
In some individuals, the disease recurs after each calving. Cows suffer from birth paresis mainly in the winter season, in whose feed proteins predominate. Avoiding the recurrence of birth paresis can be achieved by properly balancing the diet of pregnant cows. It is useful to give pregnant cows vitamin D, which contributes to the proper functioning of the entire genital area of the animal and a favorable hormonal background. Active exercise of cows is required before the first harbingers of childbirth. The disease can affect some parts of the brain, as well as the pituitary gland. In case of a violation in its work, the hormone progesterone is released into the blood, which affects the formation of the corpus luteum.
There are several other reasons for the persistence of the corpus luteum:
- lack of active walking;
- a poor feeding ration, which leads to metabolic disorders and hormonal problems in the cow's body;
- lack of vitamins A, E, D, which are necessary for the proper development and bearing of the fetus;
- lack of mineral supplements in the diet, many of which have a positive effect on the nervous and reproductive system of the cow;
- increased content of concentrates in feed.
The reasons for the development of the corpus luteum also include a history of inflammatory diseases of the genitourinary system.
Signs of persistent corpus luteum
More often, there are no signs of a delay in the exit of the corpus luteum in cows. On the contrary, outwardly, the animal looks healthy, has a good appetite. Moreover, all the signs of hunting appear: mucus comes out of the vagina, the cow makes swoops on animals in the herd. But after insemination, pregnancy does not occur.
Persistent corpus luteum is diagnosed only after several failed insemination attempts. Then the cow is examined using an ultrasound machine and a rectal method, which is performed 2 times at intervals of a month. The fact is that one examination may not reveal pathology, since the veterinarian needs to determine the difference in body size.
When examining, it is important to establish:
- the presence or absence of inflammatory processes in the genital area;
- the size and density of the ovary;
- the consistency of the gland;
- the density of the walls of the uterus, its shape and size;
- condition of the cervical canal;
- color and condition of the vagina.
An accurate diagnosis is made only after the second examination.
It is necessary to treat the corpus luteum in cattle
Most often, the prognosis of the disease is favorable. It is necessary to identify the cause of persistence and cure accompanying abnormalities in the genital area, eliminate hormonal imbalance, correct mistakes in the care, maintenance and feeding of the cow. Usually healthy calves are born after well-administered therapy.
How to treat a corpus luteum in a cow
Immediately after confirming the diagnosis, they begin therapeutic measures. The main task of the treatment is to increase the tone of the uterus, restore the basic functions of the genitals:
- the cow needs to be allowed more often to the probe bull in order to bring the female into the hunt;
- use hormonal drugs according to a special scheme under the supervision of a veterinarian;
- physiotherapeutic procedures are used, for example, ovarian massage, after which the corpus luteum leaves on its own after 4-5 days.
Sometimes they resort to surgery, removing the contents of the gland through the vagina or rectum. This operation does not require anesthesia or stitches, but it can lead to some complications.
Often veterinarians squeeze out the contents of the corpus luteum. This is a simple procedure. First, they cleanse the cow's intestines from feces. The veterinarian then gently inserts his hand into the rectum and gropes for the ovary. Then he grabs the gland and presses on it. When its contents are released, the vet clamps the cavity and holds it for about 5 minutes. This procedure does not interfere with the normal functioning of the ovary in the future.
During the treatment, it is worth paying attention to the age of the cow. If she had more than 15 calving, she is considered old, it makes no sense to prescribe therapy at that age, despite the positive result of the treatment.
Since persistence of the corpus luteum in cows is common, the owner needs to think about the prevention of the disease. First of all, you need to provide the animal with balanced feed, vitamin supplements, trace elements, arrange a daily active exercise. A cow requires careful attention and special care during pregnancy, otherwise it will not be possible to avoid various complications during and after calving. Late discharge of the placenta is also the cause of the retention of the corpus luteum, so a qualified specialist must be present at the hotel.
The corpus luteum in cows often leads to infertility.Therefore, the owner needs to diagnose the disease in time and promptly cure the animal from all inflammatory diseases of the reproductive system. Otherwise, it can lead to a decrease in productivity.