Content
The difference between abortion and premature birth is that in the first case the fetus always dies. The birth of a stillborn baby after the usual length of pregnancy is not considered an abortion. This fetus is considered stillborn. The causes of abortion are the same in all farm animals. A miscarriage in a cow in this regard is no different from an aborted fetus in a goat, sheep or pig.
Why did the cow abort?
The causes of abortion in cows range from feeding unsuitable feed to brucellosis, which is also dangerous for humans. All types of miscarriages can be divided into 3 large groups: infectious, non-infectious and invasive. According to clinical signs, abortions are distinguished:
- full;
- incomplete;
- hidden;
- habitual.
Hidden abortion does not lead to miscarriage, and the owner of the cow often does not even suspect that this has happened. More often they think that the cow went cold during the first mating and needs to be covered again.
Contagious causes of miscarriages in cows
Contagious abortions also include invasive ones, that is, caused by parasites. Such miscarriages are not infectious, since the pattern of infection by parasites is different.
Infectious miscarriages are caused by:
- brucellosis;
- foot and mouth disease;
- listeriosis;
- pseudotuberculosis;
- tularemia (not always);
- rinderpest;
- infectious rhinotracheitis;
- viral diarrhea;
- bovine respiratory syncytial infection;
- infectious bluetongue of sheep (cattle are also affected) or “blue tongue”.
Brucellosis is one of the most common infectious causes of abortion in cows. In some herds, abortions occur in 50% of cows at 5-8 months. Brucellosis is also one of the main causes of abortion in heifers. Given that this disease has no cure, in a herd that introduces heifers annually, abortions can occur for several years in a row.
Invasive abortions
They occur as a result of a cow becoming infected with parasites. In cows, only two types of parasites cause abortions: Babesia and Trichomonas. Babesia is transmitted by ticks, and the main peak of babesiosis diseases occurs in the summer. Since cows usually die in March-April, miscarriages are more likely to occur as a result of infection with babesiosis.
Trichomonas have other hosts and vectors. Infection with these parasites does not depend on the time of year. Carriers of the causative agent of bovine trichomoniasis are stud bulls. The parasite is transmitted to the cow through semen. With trichomoniasis, early hidden abortions without miscarriages occur in the 1st-3rd month of pregnancy. After this, the cow comes into heat again and again aborts. This gives the owner the impression that the cow is infertile.
Non-contagious causes of abortion
This group is divided into:
- nutritional;
- traumatic;
- idiopathic.
Miscarriage can also occur as a result of feeding feed oversaturated with mineral fertilizers. Cows often throw off as a result of overexertion or fright. Abortions occur due to poisoning by poisonous plants, when livestock consume plant estrogens, and when using uterine products.
Alimentary abortions
These are essentially miscarriages due to food poisoning. Alimentary abortion in a cow can be caused by:
- sprouted or rotten potatoes;
- moldy hay;
- rancid concentrates;
- frozen root vegetables;
- sour silage;
- stillage with mustard seeds;
- castor bean fruits and plants (a very poisonous plant);
- juniper;
- nightshade;
- tansy;
- hemp;
- mustard;
- horsetail;
- rape.
Plant estrogens, which can cause miscarriages, are found in maximum quantities in herbs at the time of flowering. For this reason, it is not advisable to give blooming clover to a pregnant cow. Cows also abort due to a lack of essential amino acids, vitamins, complete proteins and minerals in the body.
Due to the active use of nitrogen fertilizers, even benign traditional feed for cattle has become dangerous:
- peas;
- clover;
- alfalfa;
- rye;
- corn;
- roots;
- kale.
When the nitrate content is more than 0.2-0.35% in the dry matter of the diet, pregnant cows abort.
Traumatic abortions
Miscarriages resulting from:
- contusion of the abdominal wall;
- received a blow to the head;
- thermal and chemical effects;
- long-term transportation;
- stressful situation;
- too much physical activity.
If the injuries are minor, their consequences may appear only several weeks later, when the owner has already forgotten about the incident.In this case, the miscarriage will be a complete surprise and it may seem that the cow dumped her calf out of the blue.
Traumatic abortion can occur as a result of a fight between two cows in a herd. In the video below, a miscarriage occurred as a result of piercing the peritoneum with horns. The owner blames the law prohibiting dehorning. In fact, a cow can throw off even if the blow was inflicted by a rival polled cow. It's all about the force of the blow.
A stressful situation can also arise out of nowhere. As a result of explosions of firecrackers on New Year's Eve near the barn, many cows throw off from fright. If an animal drops a live calf, this is premature calving. Even if the calf died a couple of minutes after birth. When a fetus is already born, it is a miscarriage.
If the cow was forced to move too much and actively, miscarriage may occur within the next 1-2 days. This can happen if the herd is moved unreasonably quickly from one pasture to another, or if the herd is driven by dogs.
Idiopathic abortions
A type of miscarriage when the cow's body gets rid of a non-viable fetus. In veterinary medicine, it is believed that idiopathic abortions are caused by nutritional reasons or inferiority of gametes.
Similar miscarriages occur during the development of:
- abnormalities in the fetus;
- pathologies of the membranes;
- hydrops of the fetus or membranes.
Idiopathic abortion is possible even if the genotypes of the bull and cow are incompatible. In this case, there are 4 possible ways of developing pregnancy:
- hidden abortion at an early stage;
- miscarriage due to pathology at a later stage;
- death of the fetus followed by mummification or maceration without miscarriage;
- birth of a live calf with a deformity.
In the latter case, the cub usually does not live long, even if the owner tries to leave it.
Hidden abortions
Same as embryonic mortality. Their cause may be infectious diseases, injuries or genetic incompatibility. It differs from what is commonly called abortion by the absence of miscarriages. Characterized by the death of embryos at an early stage of development. The cow looks completely healthy. The only external symptom is repeated heat 28-54 days after insemination.
The main causes of embryonic mortality are:
- abnormality of fertilization caused by incompatibility of gametes during inbreeding;
- untimely insemination;
- protein incompatibility;
- chemical substances;
- vitamin deficiency E;
- immunological processes;
- inferior function of the corpus luteum of the ovary;
- blood group incompatibility;
- presence of cocci in the uterus.
The death of embryos most often occurs at critical moments of their development. One of these moments: implantation of the embryo and formation of the placental connection. But such operations are carried out on large farms, implanting an embryo from a highly productive donor into a low-producing recipient. Such manipulations are not profitable for a private owner due to the complexity of implementation and the high price.
Abortions without miscarriages
At later stages, the embryo can no longer dissolve on its own, but miscarriages also do not always happen. A dead embryo may remain in the uterus, and then there are two possible scenarios: maceration and mummification.
Maceration
This is the name given to the liquefaction of the soft tissues of a dead embryo under the influence of fermentation microbes. Maceration occurs in the middle of pregnancy. Softening of tissue is accompanied by inflammation of the endometrium of the uterus. The “freed” bones move and put pressure on the cervix. Under pressure, the neck partially opens, and the bones come out along with liquid decomposed tissue. The color of the mucus coming out is gray-brown, the smell is pungent and sour.
During maceration, the cow shows signs of intoxication, loss of appetite and depression. When defecating, first a foaming liquid is released from the vagina, and then a mucous mass with pieces of bones.
A cow will be infertile as long as she has fetal remains in her uterus. Fertilization is possible only after cleaning the uterus and restoring the functions of the endometrium.
Mummification
It also occurs when the fetus dies in the middle of pregnancy. But in this case, there are no fermentation bacteria in the uterus, but there is a reduced contractility of the myometrium and a closed cervix. Mummification occurs as a result of disruption of the reflex connection between the central nervous system and the neuro-reflex apparatus of the uterus.
With a mummy in the uterus, the cow cannot become fertilized again. The corpus luteum is in a state of persistence. Hormonal activity is reduced. Observe:
- long-term infertility;
- decrease in milk yield;
- loss of appetite;
- reduced water consumption.
A rectal examination reveals a lack of fluid in the gravid horn and an increased diameter of the middle uterine arteries without “signs of life.”
Treatment is carried out by removing the mummy.Since during the process of mummification and the further presence of the fetus in the uterus, degenerative and inflammatory processes occur in the endometrium, reproductive abilities are not always restored.
Signs of an incipient miscarriage
In the early stages, if a hidden abortion has not occurred, then there are no signs of an impending miscarriage. The fetus is expelled from the uterus along with the membranes unexpectedly for the owner. If this happens in the pasture, abortion can even be skipped.
At later stages, the signs of incipient abortion and normal calving are similar:
- decreased appetite;
- change in milk composition;
- decrease in milk yield;
- in non-lactating cows, swelling of the udder;
- anxiety;
- pushing;
- discharge of cloudy bloody mucus from the vagina.
The final stage of a miscarriage is the expulsion of the embryo. Unlike normal calving, miscarriage often results in retained placenta and inflammation of the uterus. In cows, these two factors often lead to long-term infertility.
What to do if a cow aborts
The owner's actions in the event of a miscarriage depend on the situation. Veterinary instructions provide for the disposal of non-infectious corpses in special crematoria. But first you need to make sure that the miscarriage really did not occur as a result of an infectious disease.
The calf's corpse along with the placenta is placed in a plastic bag until the veterinarian arrives. The place where the miscarriage occurred is thoroughly cleaned and disinfected. If possible, the cow's uterus is cleaned of any remaining placenta. To prevent inflammation of the uterus, the cow is given a course of penicillin antibiotics. The dosage, frequency of injections and course duration depend on the type of antibiotic used.
All veterinary procedures can be performed by a called veterinarian. This includes prescribing an antibiotic. But in real life, more often than not, everything happens as in the video below: the bedding was cleaned out after a miscarriage, the body of the calf was covered up and later simply buried without any research.
Methods of abortion therapy in cattle
Abortion is not treated anywhere. What is dead cannot be revived. It is only possible to use antibiotics to prevent inflammation and prevent miscarriages before they occur.
The only option when there is a chance to prevent a miscarriage is premature attempts. If a healthy cow starts pushing early, but the cervix has not yet fully opened, miscarriage can be prevented.
Signs of premature pushing are the same as during calving:
- the cow looks back at its belly;
- moves from foot to foot;
- worries;
- often lies down and gets up.
Possible consequences
The consequences usually do not depend on the fact of a miscarriage. If there is a “natural” miscarriage of a non-viable embryo due to genetic problems and there is no inflammation, then all the consequences are the need to breed the cow again with another bull.
If abortion occurs due to health problems and pregnancy pathology, the result can be lifelong infertility. But more often it is necessary to seriously treat the cow before trying it again.
Preventive actions
Preventative measures depend on the type of abortion.For nutritional purposes, solutions of glucose and ascorbic acid are used intravenously to prevent nitrate poisoning. The same is done when treating this type of miscarriage.
To avoid traumatic miscarriages, it is necessary to create comfortable living conditions for cows. Floors should be anti-slip to prevent pregnant animals from falling. It is necessary to exclude aggressive individuals from the herd that can damage the internal organs of other cows.
Prevention of idiopathic abortions - correct selection of parental pairs. This is only possible with purebred animals whose origin is known. In any other case, only the empirical path is possible.
In case of infectious abortions, treatment and prevention of diseases are carried out, and not the miscarriages themselves. In case of mass abortions in the herd, an examination is carried out and the cause is eliminated. After this, compliance with health standards for feeding and maintaining pregnant cows and breeding bulls is monitored.
In case of embryonic mortality, only preventive measures are possible:
- compliance with health requirements for insemination;
- insemination of a cow at the end of the heat;
- injection of progesterone solution 1%;
- disinfection of the uterus with Lugol's solution 12 hours after insemination;
- feeding with vitamins and minerals.
In practice, few people carry out preventive measures on private farms.
Conclusion
A miscarriage in a cow is a serious blow to the budget of the owner, who was counting on selling milk and a grown calf. But if in some cases abortion really cannot be prevented, then the prevention of infectious and invasive diseases is entirely in the hands of the cow owner. Vaccinations according to plan and regular deworming of the cow will significantly reduce the risk of miscarriage.
