placentitis disease - premature foaling

The books tell us that a 'Normal Gestation' duration for a mare is considered to be 340 days, however most foaling attendants will tell you that the majority of 'Normal' healthy foals are routinely born from 333 days to 347 days gestation. Earlier than 333days and you should be concerned, even if the newborn initially appears healthy.

Spontaneous abortions far outnumber premature deliveries, and the causes of abortion are many. In contrast, premature births occur occasionally (approx 1-100), and the early births are nearly always brought on by placentitis (infection of the placenta).

Common - Ascending Placentitis - this is where the infection starts at the cervix and moves forward.
Less common - Nocardioform Placentitis - this is where the infection starts down in the body of the uterus at the base of the horns.

Early Signs

There are very few outward signs from which the average mare owner can preempt placentitis. The best way to notice early signs of a problem is to get to know your mares habits. An astute breeder will recognise the smallest hint of difference in their mares behaviour. This may be the difference between a live foal and a dead one. Below a couple of the more obvious signs.

More often than not, by the time mares start showing outward signs, the underlying conditions have created so much placental damage it's difficult to do much about it. It is likely you will have a very weak foal that is going to take pretty intensive medical care to survive. In some cases premature foals are not infected by the organism that caused the placentitis and they do survive.

Your Vet can measure her progestins - Progestins are the hormones produced by the placenta throughout pregnancy, but by 310 days they are also produced by the fetal adrenal glands. After 310 days, the progestin levels go up in a normal pregnancy as an indication the foal is maturing. If there is placental disease the progestins might go up sooner than they should because of fetal stress. Between 180 and 310 days, the level should remain steady. In cases of chronic stress, it can become very high.

If it's acute stress the fetus can't handle, as when the mare has severe colic and is on the table for surgery, and the fetus is not getting enough oxygen under anesthesia, the progestins may drop very quickly. In this acute stress, the mare may abort.

If your mare has udder development and/or vaginal discharge before nine months(270 days), it may pay to treat her, but be aware that the foal might have so much abnormality it will never be a performance horse. It might be better to let nature take its course, and allow the mare to lose the pregnancy.

Other factors occasionally increase the risk of premature delivery. They include an incompetent cervix, a compromised uterus that is unable to properly support the growing fetus, and twins. Toxins and disease can rarely cause premature deliveries opposed to being a premature still birth.

In cases where the mare does show signs of early labor, but your gut tells you that all is not quite right - call your Vet immediately and do not take 'Oh it is all in your head" as an excuse. If the mare has a discharge and the Vet palpates her and finds her cervix is open, the Vet can culture her and treat her with appropriate antibiotics. Sometimes you win--we get a healthy foal.

Your Vet can use ultrasound to look at this area, perhaps see how much placenta separation there is, and assess the situation. In the event of an early birth, it's important that the Vet examine the placenta. There's a lot of good information that can be gathered from the placenta that may help to determine the cause of the premature delivery.

Early foaling may not pose a risk for future healthy pregnancies or deliveries. Early delivery is usually pretty easy because the foal is small. The risk is a little higher for red bag delivery, the placenta not coming out or leaving one horn in the uterus. If that happens, the mare could develop a uterine infection, from which there could be serious consequences. Check the placenta thoroughly for missing pieces etc.

While most foals can be expected to have healthy, normal futures without extra Vet attention, the preemie foal is usually not so fortunate. These youngsters are often born with incomplete bone formation and immature organs and are at an increased, often significant risk for respiratory problems, colic and gastrointestinal disorders, sepsis, limb deformities, muscle weakness, hypothermia, hypoglycemia, diminished suckle reflex, and ineffective swallowing. At maturity, they often remain undersized, lack athletic ability, and have chronic problems. Some immature characteristics such as silky hair coat, overly pliable ears, weak or lax flexor tendons, and their small size.

In cases of infected placenta or placentitis, there are several treatments Vets can use. The mare is usually placed on antibiotics, because most often the infection is caused by bacteria. The mare might also be given progestins (such as Regumate) and sometimes an antiprostaglandin (a non-steroidal anti-inflammatory drug).

Phenylbutazone, Bute, might stop udder development and have a quieting effect on the uterus -- reducing its contractions. When the uterus is inflamed, it wants to contract. When it contracts, it compromises the blood flow and there is less blood supply to the foal. You want the uterous relaxed. Regumate and other synthetic progesterones also have a calming effect on the uterus. The use of these drugs is somewhat controversial.

If you can afford IV doses of penicillin and gentamicin for a few days. Since IV administration is quite expensive, you can usually switch to intramuscular penicillin. Some Vets also use vitamin E. This might help prevent some of the damage that could occur if the foal experiences a drop in oxygen.

Foal Prognosis

The outlook for the premature foal depends on its gestational age, cause of early birth, neonatal condition, and the speed and quality of the supportive care it receives. Odds decrease considerably for foals born before 300 days.

These foals usually have a very poor survival rate, even with a lot of intensive care and If they do survive, they usually have such serious, life-long health and soundness problems that it's considered impractical to try to save their lives.

In the event of a premature birth, owners should first make sure the foal is kept warm, then call the Vet. Newborns incapable of rising or nursing should be examined immediately. Foals that are getting up on their own and are nursing should be seen within four hours, even if they appear to be normal other than their small size.

** Dysmature
These are foals born on their due date, however, they show all the signs of a premature foal - soft or silky coat, floppy ears, loose tendons / joints, noticably large dome on it's forehead and small stature. Dysmaturity can occur when the foal is not receiving the nutrition it needs to grow whilst in-utero. Foals born with the these signs have very similar problems to premature foals.

The biggest mistake is not seeking Vet help early enough. The foal is going to look its best at birth or soon after its born, but their condition may start to deteriorate 24 to 48 hours later and spiral downward. You want to have that foal assessed by a Vet and started on the appropriate therapy so it won't become more compromised. Be sure to include Ulcerguard in the foals treatment as stress may cause an ulcer and the poor foal is dealing with enough without a bleeding ulcer on top of all of this.

To evaluate the foal and its chances, the Vet will begin with a history of the mare. How far along was she when she delivered? Did she have any signs of premature delivery beforehand or did she just deliver prematurely without any kind of warning? These answers will give the Vet an idea on what to expect and how they are going to approach this foal.

An important factor is that foals stressed in utero are usually much more developed than foals that have not been stressed, so the presence or absence of signs of pre-term birth are meaningful. The stress produces an increase in cortisol release, which causes advanced maturation of vital organs such as the lungs. This 'stress' may be due to the presence of placentitis, sickness in the mare such as colic or endotoxemia, or any other situation that is ongoing.

After collecting mare history, the Vet will examine the foal. The foals appearance, mentation, and how they're acting will really determine what I do next. Can the foal get up on its own, is the foal nursing, does it have a suckle reflex? Does it have a shiny, thin coat and floppy ears, which are signs of premature development? Are its bones completely ossified?

They will then try to categorize the foal into one of three groups:

Critical
The critical foal is very weak and suffering from multiple system failures. This newborn is unable to rise or lift his head and lies on his side, gasping for oxygen. It is usually septic and often in shock. Most critically ill foals are from mares that have shown no signs of impending delivery. Because it's organs may not be completely developed and functioning properly, it's going to need oxygen and extensive supportive hospital care to survive, including plasma transfusions to bolster the immune system, significantly increased nutrition, and orthopedic supports such as splints or casts. Hospital stays usually last at least a couple of weeks, or sometimes longer, so treatment can be costly.

Additionally, these foals have a lower percentage of survivability, and if they do survive, performance is unlikely to meet expectations. Consequently, the decision to treat becomes a matter of intended goal, practicality, and financial.

Stressed
The foal that's been stressed in utero is a little small and weak, but it can get up and nurse and behaves pretty much like a normal foal. Care, such as meeting nutritional and immunological requirements, administering preventive antibiotics, and identification of ossification of bones, can be performed on farm.

Average
The average foal is a little weak and doesn't have much of a suckle reflex, but it is bright, attempts to stand up, and can be assisted up. These foals can also be treated on farm. Supportive care is often directed at helping them gain strength and preventing sepsis or other complications from occurring such as: nasal tube to deliver nutrition, administration of fluids to prevent dehydration, supplemental plasma to bolster the immune system, and antibiotics to ward off infection, if needed use of heat lamps for warmth, and limited exercise while bones complete their formation. The outlook for the latter two groups is generally pretty favorable. With supportive care and time, these foals can continue to do well. They may be smaller than the others in the beginning, but a lot of them can grow to their full potential.

Prevention
Maintaining a good health program throughout the mare's pregnancy with appropriate nutrition, vaccinations, deworming, and regular observation of your mares behaviour, have been the primary means of improving the odds for a normal, full-term delivery.

The often over looked factors - TEETH - the old saying - if your teeth are sick then the rest of your body will follow, is so true. Have your mares teeth done when she is being prepared for mating and again 6 months into her gestation. Healthy teeth healthy mare. FEET - Just because she is a broodmare and not in full work, does not mean her over grown feet will not throw her back or hips out. Causing a domino affect to her overall comfort and well being.

Some Vets will perform transrectal ultrasound exams of the placenta in order to detect signs of early placental disease, in suspicious cases. Be sure to ask your Vet if they will perform this examination if they deem it necessary. They will examine the mares at the cervical star, the area of the placenta that is up against the cervix). That's where you start to see lesions with ascending placentitis. High-risk mares should br checked at about 150 days gestation, then every 30 days.