The spring season brings with it the long awaited arrival of foals. Once your mare and foal have bonded it is time to do a thorough examination of the foal to make sure that everything is within normal limits.
The initial exam should consist of a TPR (temperature, pulse rate, respiratory rate). Newborn foals, those less than one week of age, have different “normals” than adults. Normal temperature in a newborn foal is 99.5-102, higher than an adult horse. Normal heartrate (HR) for a foal is greater than 60 beats per minute (bpm) and can range from 80-100 bpm during the first day. Normal respiration rate (RR) is 30 breaths per minute, with the range from 20-40 breaths per minute. The heart and lungs should be ausculted for any abnormal sounds such as murmurs, irregular rhythms, or crackles and wheezes. Gastrointestinal sounds can be ausculted with a stethoscope as well.
The rib cage of newborn foals should be carefully palpated to feel for any rib fractures that may have occurred during parturition. Fractured ribs are painful can cause serious damage is a sharp broken end lacerates the artery that runs along the rib, or in some cases, can puncture the lungs or heart. Any concern or question about possible rib fractures should be brought to your veterinarian’s attention. Radiographs or ultrasound may be needed to confirm the fractures. Some can be managed conservatively, while others may require surgery to stabilize them.
The foal’s abdomen should be palpated for the presence of any body wall hernias. These can occur in the umbilical, inguinal, scrotal regions. A hernia is a protrusion of tissues or organs through an abnormal opening. In foals umbilical hernias are most common. The area surrounding the umbilicus is one of the last areas of the body wall to close during development. Incomplete closure of the body wall results in a defect that can be palpated as a hole in the muscular body wall. Normal foals will have a very small hole (smaller than the tip of a finger) at the umbilicus that will gradually shrink and disappear as the umbilicus dries up and falls off. Umbilical hernias usually appear as a soft sack on the underside of the belly and can vary in size from just a few centimeters to very large (up to 12 cm). Umbilical hernias should be non-painful and the contents should be easily reduced back into the abdomen. For smaller defects, reducing the contents into the abdomen several times a day may allow for them to close. Larger defects will require surgical correction.
Failure of Passive Transfer
Foals should be up and nursing within 1-3 hours of birth. It is very important for foals to ingest this first milk, known as colostrum, as soon as possible, and definitely within 24 hours of birth. Colostrum is very important because it is rich in antibodies, protein and calories. The mare transfers her antibodies to the foal primarily through the colostrum. These antibodies protect the foal against environmental diseases. These antibody proteins are also called immunoglobulins or “IgG”. They are very large in size. The foal’s small intestine will only absorb these large proteins during the first 12-24 hours after birth. After 24 hours, the only way a foal can absorb more immunoglobulins is by a plasma (intravenous) transfusion. It is recommended that a veterinarian check the foal’s IgG levels within the first 12-16 hours after birth. A normal IgG level is greater than 800 mg/dL. A level of 400-800 md/dL indicates partial failure of passive transfer. A level of less than 400 mg/dL is considered complete failure of passive transfer. Without these antibodies, your foal is susceptible to disease. If the foal’s IgG <400 mg/dl, the foal has a 25% chance that it will contract a disease if exposed. If the foal’s IgG< 200 mg/dl, the foal has a 75% chance it will contract an environmental disease if exposed. Your veterinarian can pull blood from your foal and do a stall side test to measure the IgG level and determine a course of action. If you get a low reading before the foal is 24 hours old you can supplement with oral colostrum. If it is past 24 hours, them IV plasma is needed. Most foals tolerate plasma transfusions well and it can be done on the farm.
Once a foal is up and nursing, it should start passing its first feces (meconium) within a few hours. The foal will pass multiple small piles of meconium. All of the meconium should be passed within 24 hours. The meconium is dark brown, firm fecal balls. If the foal is straining a lot, you can give a Fleet enema to help the foal pass the meconium. After all of the meconium has passed, the foal will start to defecate thick, pasty, orange colored milk feces. This is a good sign indicating that milk has made its way through the entire digestive tract. Not nursing, straining, rolling up on their backs, and teeth grinding are all signs of colic in foals.
Lax and Contracted Tendons
Newborn foals often are born with lax tendons that make it look like they are walking on the backs of their fetlocks. Confining the foal to a stall for a day or two usually will resolve the problem. Wraps are not indicated, as they may weaken the muscle/tendons more, but you can put a light “band-aid” of vetrap on the limbs if they are getting rubbed.
The opposite condition, called contracted tendons in foals, is more serious. These foals appear very upright. The fetlocks or pasterns may even buckle forward. This condition can be painful, as the foals try to stretch the overly tight tendons. This may prevent them from standing and nursing. Mild cases can benefit from physical therapy (stretching exercises and controlled exercise. More severe cases can be treated with IV oxyteteracycline that helps to bind calcium and causes muscle relaxation (and by extension, tendon relaxation). Therapy is usually repeated for up to 3 days. Bandages can be helpful in these cases.
Occasionally during delivery, a foal’s bladder can be ruptured. This happens most commonly in colts (90%). Signs of the rupture usually become apparent within 1-7 days after birth. The foal’s abdomen may become enlarged from the urine leaking into it, the foal will become depressed, may show signs of colic, and might dribble urine. Electrolyte abnormalities will begin to occur as the urine accumulates in the abdomen (uroperitoneum). Contact your veterinarian if your foal is straining to urinate, doesn’t pass a good stream of urine, or has an enlarging abdomen or is becoming depressed.
Neonatal Isoerythrolysis (NIE)
NIE is an immune mediated hemolytic condition inherited from the stallion. The mare produces antibodies against the foal’s red blood cells which have a marker on them inherited from the stallion. The antibodies produced by the mare are concentrated in the colostrum. The foal is normal at birth. But after ingesting the antibodies in the colostrum, these antibodies attach and destroy the foal’s red blood cells. The foal typically shows signs of weakness, jaundice (yellow coloration of the gums, white of the eyes, vaginal mucosal) and anemia within 12-24 hours.. Prevention is key. If the mare has a history of NIE foals, the mare can be tested 2-3 weeks prior to the foaling date. The mare is crossmatched with the stallion (stallion red cells and mare serum), during this time when exposure to the foal’s erythrocytes is likely to occur (thus boosting the antibody titer, if there is an incompatibility). If there is any question of NIE, the foaling should be attended. The newborn foal should be muzzled the first 24 hours and fed an alternate source of colostrum. The mare’s milk should be stripped (milked) out the first day. This condition is rarely seen in maiden mares, and is more commonly seen in foals when the mare is bred back to the same stallion carrier. Treatment includes a whole blood transfusion if it is diagnosed early enough. Severely affected foals may required hospitalization with oxygen therapy.
Septicemia, an infection in the blood stream, is a serious and life threatening condition of foals. Infection can enter the blood stream through many routes, including via the placenta (in utero), umbilicus, gastrointestinal tract, and lungs. Foals may be sick at birth or appear normal at birth and quickly deteriorate in condition. Signs of septicemia include fever or hypothermia (foals often get colder, not hotter, when they are sick). Other signs include loss of suckle reflex (you can often recognize this by observing a full bag on the mare or the mare may be squirting milk), lethargy, depression, or recumbency. Septicemia is diagnosed based on complete cell count (very high or very low white cell count), high fibrinogen, and a blood culture. Antibiotic therapy is crucial and should be based on culture when possible, but broad-spectrum therapy should be instituted while waiting for the culture. Septic foals may require supportive therapy such as plasma transfusions, oxygen, oral or IV nutrition, and anti-inflammatories.
Neonatal maladjustment syndrome, hypoxic-ischemic encephalopathy, dummy foals. There are many names to describe what results from lack of oxygen during parturition due to placental separation, dystocia or septicemia. Several other syndromes due to lack of growth in utero or dysmaturity can also present with similar signs. These foals can show signs of seizures, irritability, spastic movements, inability to suckle, wandering, or barking (abnormal vacalizations). This is a very serious condition and requires intensive and often prolonged treatment. Many of these foals will go on to lead normal lives if their cases are not complicated by sepsis or other infections.
This is by no means a comprehensive list of everything that can wrong with foals, but it does give a good overview of what to be on the lookout for when your bundle of joy hits the ground. Knowing what is normal, and abnormal will help you keep you foal healthy from the start.
Registered 2014 Equestrian Collections; Author: Sallie S. Hyman, VMD, DACVIM, CVA
Information in this article is for educational purposes only and is not a substitute for evaluation by an equine professional. In particular, all horse owners should seek advice and treatment from a licensed veterinarian for their horses’ medical care.