Infertility and Abortions in Female Animals .......................................................................

10.7.5 Infertility and Abortions in Female Animals Infertility is the failure to reproduce offspring. This can happen for many different reasons. For a review of infertility problems see page 164, general guidelines regarding breeding of livestock.

Taking a history and doing an examination is very important. This may reveal specific causes, such as whether the animal was exposed to any toxins, had a high fever, received certain medicines or vaccines, was injured, or has a poor diet.

The first step is to decide if the female animal is the reason for the infertility, or if the male animal is the reason.

 If the female animal has been bred by several different males, and still does not produce babies, then it is probably the fault of the female.

 If several female animals have been bred by the same male, and most of them aren’t pregnant, then it is probably the fault of the male animal.

In female animals, there are two common types of infertility:

1. No heat. The female never shows signs of heat.

1. Repeated breeding and abortions. When the female comes into heat and is bred, but fails to become pregnant, the term used is repeated breeding. In fact, she may come into heat more often than normal. Or, the female becomes pregnant but never completes the pregnancy in a normal manner. This can happen if the baby dies in the uterus, or if it is born too early to live, and is called, “abortion.“ The most common causes for infertility and abortions are:

 Infection  Malnutrition due to a poor diet, or parasites  Certain medicines and vaccines  High fevers  Injury  Toxins What are the possible reasons why an animal may not come into heat?

Already pregnant! This is the most common reason why a female animal does not come into heat. Perhaps she was bred without the owner knowing it (e.g. she was loose and came into contact with a male or vice versa).

Treatment: Wait to make sure the female is not pregnant. If possible, get a veterinarian or technician to perform a rectal examination and check for pregnancy. At the same time, they can check the ovaries and uterus for other problems.

The Owner Cannot Tell When the Animal Is In Heat. It is important to review with the owner how and when to recognize the signs of heat in her animals. See page 135.

“Silent Heat.” Sometimes the female comes into heat but does not show the normal signs of heat. This happens more often if there is no male animal nearby.

Treatment: Keep the female with, or near, a male animal during the breeding season. Even if the owner cannot tell if the animal is in heat, the male animal probably can.

Old Age: Check the teeth of the animal to estimate its age. If the animal is very old, explain this to the owner.

Treatment: Old animals should be culled from the herd and replaced with younger animals. This should be done on a routine basis so that the herd of animals does not become old all at once. For example, 20 percent (1/5) of a herd of sows should be culled and replaced yearly, so that there is a proper mixture of older and younger animals.

Malnutrition / Deficiency: Some animals may lack something in their diet that prevents them from coming into heat. The most common cause is lack of enough energy in the diet (i.e. the animal is thin). The problem is made worse if the animal also has many parasites. In many tropical countries, the soil and plants lack a mineral called phosphorus. Animals suffering from phosphorus deficiency may not reproduce normally.

Treatment: Feed animals a balanced diet and make sure that they have enough energy so that they aren’t thin and sickly. See page 106. In addition, treat them for parasites.

Note: Ask the government extension worker if any mineral deficiencies are common in your area. If so, consider feeding extra minerals based on the advice of a local specialist. Do not depend on expensive phosphorus or vitamin injections. Rather, feed vitamins and minerals with the food.

Caution: Many livestock owners are exploited by vendors of vitamin injections or mineral products. In some cases, inexpensive local feed sources can provide the needed vitamins and minerals. Often, the more important problems are parasites and insufficient foods containing energy.

Too fat: Female animals that are too fat often fail to come into heat and get pregnant. They may also have trouble giving birth, or give birth to weak offspring.

Treatment: Feed smaller quantities of a well-balanced feed until the animal loses weight.

Infection: Metritis may also cause infertility. See page 161.

Problems with the Ovaries or Uterus: If the possible causes mentioned above are eliminated, then there may be something wrong with the ovaries that prevents normal heat. An animal that has a deformity in its reproductive organs may fail to get pregnant, or may abort once pregnant. This is often the case when a cow gives birth to twins - one of which is male and one is female. In cattle, 95 percent of female twins do not have a fully developed reproductive tract and are infertile. In America, these female twins are called “free-martins.”

Many of the causes for repeated breeding and abortions are similar and can be considered together.

Malnutrition (deficiencies)

This is due to a poor diet or parasites. See pages 51, 125,176, 196.

Cyst on the Ovary A cyst is a fluid-filled lump that may develop on the ovary of a female. A cyst may produce hormones that disrupt the animal’s normal heat cycle. The female animal may exhibit strange behavior, such as being in heat continuously, exhibiting male behavior, or never showing signs of heat. The following two types of cysts are most common:

Follicular cyst Symptoms: The animal comes into heat, and then comes into heat again before she should.

Diagnosis: Based on symptoms. The cyst can be confirmed by a rectal exam (done by a skilled person).

Treatment: Give an injection of a hormone containing chorionic gonadotropin (also called HCG). If this injection is not available, an old treatment is to use a pipette and put about 10 ml of 5 percent iodine solution into the uterus.

Prevention: Cystic ovaries may be caused by injections of estrogen hormones, or by eating certain forages that are high in estrogens. Seek advice of a skilled person if you suspect a problem of cystic ovaries in your area. Consider culling animals with chronic cystic ovaries (especially if the problem occurs more than once) since a tendency for cystic ovaries may be passed to the offspring.

Luteal cyst Symptoms: The animal does not come into heat at all.

Diagnosis: Based on the symptoms.

Treatment: Give an injection of prostaglandin. If the treatment is effective, the animal should come into heat within 3 days. If prostaglandin is not available, put iodine into the uterus as described above.

Prevention: Consider culling animals with cystic ovaries (especially if it occurs more than once) since a tendency for cystic ovaries may be passed to the offspring.

Infections Metritis (infection of the uterus) has already been discussed as a disease of the uterus. See page 154. Metritis is also a common cause of infertility. In addition to general metritis, many different germs cause infections that result in infertility and abortions. Determining the exact germ, even with the help of a laboratory, is often difficult. However, the following organisms are the most common causes of metritis:

 In cattle, an organism called “trichomonas” can cause infertility or irregular heat cycles. Cattle transmit this to other cattle during breeding.

 In pigs a virus called “parvo” can cause infertility, abortions or mummified piglets.

 The following section describes two of the most common infections that cause abortions.

Brucellosis Brucellosis is due to a bacteria called Brucella and may cause abortions, infertility, and inflamed testicles of cattle, buffalo, goats, sheep, pigs, and dogs.

Brucellosis is also an important public health disease because it can cause “undulant” or “Malta” fever in humans. The symptoms in humans include a fever that increases and decreases (i.e. undulant) as well as headaches and general weakness. See page 281. Humans are infected by contacting the placenta, drinking milk, or when slaughtering an animal for meat (particularly pigs).

Animals are infected when the organism enters their mouth through contaminated food or water, or by having contact with infected animals, particularly their placentas. The bacteria then enter the uterus and cause abortions during late pregnancy. The abortions may be followed by retained placentas and subsequent infertility. Brucella bacteria are also present in the milk of infected animals.

Diagnosis: Diagnosis can be made from a blood sample or from culturing an aborted animal, the placenta, or milk.

Treatment: None.

Prevention / Control:

 In many countries, government authorities require blood testing to identify infected animals which must then be slaughtered.

 In some countries a brucellosis vaccine is licensed and available, but an AHA must handle it properly and according to the label instructions and regulations of her country.

 Aborted animals, and the associated placenta, should be buried or burned. Keep other animals and humans from touching them.

 Humans should always boil milk before drinking it to kill Brucella, as well as other harmful organisms.

Caution: Never treat an animal with a retained placenta that just aborted without wearing a plastic glove. Always wash your hands and arms afterwards. If accidentally exposed to Brucellosis, take 500 milligrams of tetracycline, by mouth, four times a day for two weeks.

Leptospirosis Leptospirosis causes disease in animals and humans. See page 287. Dogs, pigs, cattle, rats and wildlife serve as sources of infections. The organism comes out in the urine of infected animals. Animals and humans become infected by drinking contaminated water, or by contact with the urine of infected animals.

Symptoms: Young animals can become quite sick with fever, jaundice, and red urine (called hemoglobinuria). See page 246. Anemia, and possibly death may follow these symptoms. Adult animals may have abortions late in pregnancy, or lowered milk production with thick, yellow, blood-tinged milk yet with no inflamed udder. Sometimes there are no symptoms, particularly in pigs and adult animals that are not lactating.

Diagnosis: Diagnosis is often based on symptoms. It can be confirmed by a blood test.

Treatment: Treatment with tetracycline or streptomycin may help if done early in the course of the disease.

Prevention/Control: Simultaneous treatment with streptomycin and vaccination may help control an epidemic, if done early. Streptomycin stops the shedding of the organism in the urine. Rat control also helps.

Certain Medicines and Vaccines as a Cause of Abortions Certain medicines and vaccines can cause abortions. This is why it is very important to read the label on all medicines before using them. If the label is difficult to understand, ask someone to help. Some common medicines that cause abortions in animals are:

 steroids, such as dexamethasone  estrogens (used to make female animals come into heat)

 prostaglandins (used to make female animals come into heat)

 Carbon Tetra-Chloride (CTC) - used to treat liver fluke High Fevers or Overheating as a Cause of Abortions Overheating or any condition that causes a high fever in an animal may result in abortion or failure to conceive. Some diseases that cause high fevers and hence abortion or failure to conceive include hog cholera, African swine fever and erysipelas in pigs, foot and mouth disease in cattle, and anthrax in any species.

Treatment: In hot climates, it is always wise to avoid overheating by breeding animals, especially pigs, early in the morning or later in the evening. Provide protection from the sun and extreme heat. Do not overheat animals during transport, handling, castrating, vaccinating or worming. Consider transporting animals only at night. See page 62 for treatment of overheating, or a high fever.

Trauma, Stress, Injury as a Cause of Abortions An animal that has had trauma or stress may be infertile, or experience early abortion. Stress or trauma could be due to an accident or a fall, injury from other animals (particularly from horn butting), rough handling, a long voyage, overcrowding, or lack of shelter from excessive cold, mud, wind, sun, or heat.

Toxins as a Cause of Abortions  Certain plants may contain toxins that result in abortion or infertility. For example, the tree called Leucena produces a toxin called “mimosine.” Although the Leucena leaves provide rich forage, if these leaves are eaten in large amounts, they may result in infertility or abortion in certain species.

 Feed that is stored improperly, or becomes wet, may become moldy. This mold can produce a toxin called a “mycotoxin,” which can cause infertility or abortion.

 Microorganisms that cause certain types of mastitis or other infections may produce toxins that poison the animal. This is called, “toxemia,” and may result in abortion.