Mare & Foal Care
Ron Friedman, M.S., D.V.M.
Diplomate American College of Theriogenologists

(Presented at the SW Washington Horse Symposium, Nov. 8, 1997)

The topic of mare and foal care is a vast one. In this talk I have attempted to cover a few selected topics regarding breeding, pregnancy, nutrition, and foaling in the mare. Topics discussed on the foal include early care, vaccination, deworming, and feeding. The coverage is by no means in great depth, if you have further questions on the care of the mare and foal there are many sources out there but please feel free to contact our office.

I. Breeding your mare:

Many opportunities exist today in breeding mares, live cover, ai (artificial insemination), chilled transported semen, frozen semen, and embryo transfer to name a few popular methods. The choice is often made based on stallion preference, convenience, and breed registry rules.

The physical condition of your mare can greatly influence the outcome. If the mare is obese have her lose weight before going to the breeding shed. Mares losing weight take longer to achieve pregnancy compared to mares gaining or maintaining their weight. Similarly, excessively thin mares may not cycle regularly.

Live cover & AI
Live cover is still practiced with great success, although it poses some risk to all involved: mare, stallion and handlers. Pregnancy rates for ai are slightly higher than live cover followed by chilled transported semen and frozen semen. Availability of frozen semen is less than the other methods and more palpations of the mare are required to maximize the chances of success. More mares than ever are being bred with chilled transported semen because of the ease of breeding to a stallion across the country and the approval of the AQHA.

The goal of most breeding farms is efficiency and it is best realized by breeding the mare as few times as possible as close to ovulation as possible. Better results are not achieved by multiple breedings nor by breeding daily. If you will be transporting semen ask about the stallions pregnancy rates with shipped semen.

When choosing a farm consider its facilities, would you want to leave your mare there? Are their stalls cleaned regularly, are their fences safe for horses and in good condition? Discuss expenses and breeding procedures at the farm. In most mares it is not necessary for successful pregnancy to leave the mare at the farm until pregnancy is detected.

II. Pregnancy

Pregnancy ranges between 330 and 345 days with many mares foaling after 12 months. During pregnancy it becomes very important to carefully consider what your mare eats and is treated with. Make sure any medicine, vaccine, dewormer, or supplement is not contra indicated for pregnancy

A) Exercise
Regular exercise is as necessary in the pregnant horse as it is to any horse. If the mare is in a regular exercise program prior to pregnancy it should not be discontinued when in foal. If the mare is not being exercised, a regimen of light routine exercise will improve her muscle tone and ease birth. Unless there is a specific reason suggesting otherwise, the mare should be exercised until her size and pregnancy hamper her ability to move or breathe easily. Exercise levels and times should not be changed drastically, nor should she be asked to do strenuous work without regular exercise. In other words, avoid working the mare hard for only 1 or 2 days a week; regular exercise is the key.

B) Nutrition, feeding and supplements
Excerpts from Feeding and Care of the Horse. Lon Lewis, Lea & Febiger 1982

By far, the most common errors in feeding broodmares is overfeeding during pregnancy and underfeeding during lactation. Fetal and lactational requirements dictate three types of feeding regimens for the broodmare. It should be noted that with the high nutritional demands of lactation good teeth are essential.

1) First eight months
Feeding requirements are the same as non pregnant horses and are dictated by work load. "Feeding for two" is probably the most common mistake. Supplements are ill advised unless you know there is a deficiency in the ration. The Pacific Northwest is known to be deficient in selenium in certain areas and supplementation may be necessary. Protein requirement is 8% on a dry ration basis.

2) Last three months
The fetus grows tremendously during this time and the mares protein, energy, and mineral requirements increase accordingly. With good quality forage and balanced grain ration it is often possible to balance the ration without many additional supplements. Protein requirement is 10% on a dry ration basis.

If grass hay or pasture is fed, calcium, phosphorus and protein may be the limiting factors and may be supplied with a concentrate mix. Fresh short green grass often contains enough protein for the pregnant mare, while long mature grass or grass hay often is deficient. If the pasture has legumes in it protein and calcium may be sufficient. If protein is adequate, phosphorus can be supplemented with a salt-mineral mix containing equal parts phosphorus to calcium.

If a good quality alfalfa or other legume is in the ration often the only supplement needed is phosphorus and this may be supplied as a low calcium, high phosphorus salt-mineral mix. The additional demands of pregnancy can be met by merely increasing the amount of forage. However over feeding is the most common mistake. If the mare needs to lose weight do not attempt weight reduction during the last three months of pregnancy.

3) Lactation
Lactation is one of the most energy and protein demanding times for any horse. Some mares, if not fed enough, will lose significant weight. During the first 3 months of lactation, a one thousand pound mare will produce 25-30 pounds of milk daily! Protein requirement is12.5% on a dry ration basis, while energy demands are increased 100%. Deficient protein, energy, calcium or phosphorus results in less milk production but doesn’t affect the quality of the milk. By the fifth month of lactation milk production is roughly 5 pounds per day.

The mare should be fed sufficient quantity and quality of feed to prevent loss of weight or body condition. A good rule of thumb is that the ribs should not be seen but easily felt. Overfeeding hay during lactation is not likely, feed as much as she will eat, often as much as 25-30 pounds per day for a 1000 pound mare.

If good quality alfalfa or other legume is fed the increased nutritional demands of lactation can be met by increasing the volume of food and allowing free access to mineral-salt mix containing calcium and phosphorus. A supplement containing high phosphorus is preferred but equal amounts of each is acceptable.

If grass hay is the forage used, adding a concentrate mix is preferred to cereal grains. Depending on the type of concentrate used, approximately 10 pounds daily should be fed along with all the grass and hay she can eat (for 1000 lb. Mare). This amount should be gradually decreased through the lactation.

C) Vaccination and deworming
Mares should be de-wormed, as all horses every 6-8 weeks depending on their stabling conditions. Mares housed with many other horses will have a higher exposure to parasites, while those living alone or in small groups have lower risk. There is no consensus regarding rotating dewormers each time or seasonally. Make sure the product is approved for pregnant mares and deworm one month before term.

Vaccination of mares likewise is essential but again ensure that there is no warning against use in pregnant mares. Vaccination for Rhinopneumonitis abortion should be done with a product approved for such use on the 3^rd, 5^th, 7^th, and 9^th month of pregnancy.

A newborn foal is born without any immunity against disease. All the immunity is acquired from the colostrum. To ensure adequate immunity in the colostrum, mares should be vaccinated 4-6 weeks prior to the anticipated foaling date with whatever you want protection against. Tetanus toxoid is a must and other general recommendations often include, Encephalitis, and Rhino/Flu.

III. Parturition and neonatal foal care

A) Preparation for foaling
Preparing for foaling is the best insurance against a problem. Fortunately most pregnancies and deliveries are without complication. Signs of impending parturition include:

• Udder begins to fill 2-4 weeks
• Softening of croup @ 2 weeks
• Teats fill 4-7 days
• Restless walking 1-2 days
• Clear to Yellow to whitish milk ü - 7+ days

The changes observed are often more important than the signs themselves. The best predictor of foaling is obtained through milk calcium levels. A commercial water hardness test Softchek¬ works well. Softchek¬ is available from many plumbing supplies or through the manufacturer:

Softchek Water Hardness Test Strip
Environmental Test Systems
PO Box 4659, Elkhart, IN 46514

1. Strip out a small amount of milk.
2. Mix 6 parts distilled water per 1 part milk.
3. Wet the Softchek¬ strip and wait 15-30 seconds.
4. Result of 250 or more ppm mean that 95% of mares will foal within the next 12 hours.

Immediately before foaling clean the stall and bed with straw. Wrapping the tail is helpful but don’t apply too tightly or leave on longer than a few hours. Doing so can have catastrophic consequences on the tail. Keep the mares environment calm and free of commotion and loud noises.

B) foaling
Foal birth in the mare is usually uneventful. Following is a rough time frame of some hallmarks (easy to observe) of foaling and some complications we see.

Normal and abnormal events of foaling. Look at time

Call your veterinarian if:

1. Timeframe above is way off.
2. Progression of feet, head, body is longer than 15-20 minutes.
3. Mare is pushing hard for 10 minutes and nothing happens.
4. Placenta is not passed by 3-6 hours.
5. Any of the problems described above appear.

C) Early Foal Care: Immediately after foaling:

1. Ensure foal is breathing; drying with towel helps stimulate breathing.
2. Dip navel in 7% iodine. Keep it on navel, not thighs. Will stain everything.
3. Ensure foal nurses. Foals only absorb colostrum the first 12-18 hours. It’s possible to check the quality of colostrum at this time
4. Tetanus shot only required if mare unvaccinated at 10 mo. In those cases use tetanus antitoxin
5. Leave mare and foal alone!

D) Newborn Veterinary exam (first 1-2 days of life)

1. Check foal’s circulating immunity (IgG passive transfer)
2. Antibiotics are not indicated.
3. Observe for normal defecation and urination
4. Complete physical exam.
   

i. mouth: - symmetry of bite, cleft palate, normal gum color
ii. Umbilicus - wet, dry, hernia, ruptured bladder, persistent urachus
iii. Eyes - eyelid problems, vision
iv. Heart - murmurs are normal at this time
v. Lungs - good breathing effort, no infection
vi. Legs - contraction, looseness, swelling, heat or pain

 

IV. Vaccination, deworming, feeding and weaning

A) Foal Vaccinations
If foal is from vaccinated mare, no vaccines are necessary during the first few months. If from unvaccinated mare give tetanus antitoxin as soon as possible, some protection supplied but lower quality than with colostrum. For more information see "How Vaccines Help" & "Equine Immunizations"

1) Tetanus
It is noteworthy to differentiate between Tetanus toxoid & antitoxin

Tetanus Toxoid: A Vaccine, not a treatment
Stimulates a horses immunity approximately 3-4 weeks after vaccination

Tetanus Antitoxin: A Treatment, not a vaccine.
Gives quick protection which lasts 2-3 weeks, but level of protection is lower

From unvaccinated mares or lack of colostrum

• birth: tetanus toxoid and antitoxin
• booster at 1 & 3 months old with tetanus toxoid

From vaccinated mares

• 3-4 months of age with tetanus toxoid
• booster 3-6 weeks later with tetanus toxoid

2) Encephalitis (Eastern & western)

• protection from colostrum can last 6-7 months
• first dose at 3-4 months old
• booster 1 month
• If 1^st vaccinated at a younger age, 3^rd booster at 6 months

3) Influenza
(Note: Until now recommendations were as shown below.
Current research indicates 1^st vaccination at 6 mo. of age!)

From unvaccinated mares or lack of colostrum

• If high exposure, start at 1 month old
• If not high exposure start at 3 months old
• Booster every 4-6 weeks until 7 months old

From vaccinated mares

• if high exposure, start at 3 months old
• Booster every 4-6 weeks until 7 months old
• if not high exposure, can start at 6 months old

4) Rhinopneumonitis (Rhino)

• first dose at 2-4 months old
• booster 3-6 weeks

5) Potomac Horse Fever

• 3-4 months of age
• booster 1-2 months later
• If 1st vaccine was at less than 3 months old: booster monthly until 5 months

6) strangles

• Only in areas with disease present
• 2-3 months old
• 3 doses, 2-4 weeks apart
• booster at weaning or at 6-8 months

B) Foal Parasite Control
De-worming can start at 4-6 weeks of age. Many products are available to de-worm horses but some of the best methods of parasite control are not currently popular. If you avoid overgrazing (more than 1 horse/2 acres) pastures and remove feces from paddocks weekly, parasite numbers are much less. Regular pasture maintenance by mowing and harrowing also reduces egg and larvae numbers by exposing them to the elements. Feed off the ground in bunkers and clean them as well as waterers weekly. Keep mares and foals separate from other horses and save the least grazed pastures for mares with foals. For more information see "Intestinal Parasites".

C) Feeding foals and Weaning
Foals grow the fastest during the first 3-5 months of age. Lactation is at its peak from 6-10 weeks after foaling. Mare’s milk usually supplies all the nutrients a foal needs especially if the foal has access to nibble on its mothers forage and concentrates. If adequate forage is not available as the foal grows then additional concentrate feeds should be supplied.

In most situations today the major problem seen with foal nutrition is overfeeding. Feeding the foal a separate "creep" feed is not needed if the foal is growing at a normal rate. Overfeeding and too rapid a growth rate can increase the incidence of musculoskeletal disease in the foal e.g. OCD, contracted tendons, and epiphysitis to name a few.

Prior to weaning, a commercial creep feed can be fed on an ad lib basis or at the rate of 1to 1ü lbs. per 100 lbs. of foal. Close observation of the foal is recommended and if growth is too rapid limiting the feed is beneficial.

Weaning should be done before 7 months and if managed well will lessen stress on the foal. When separating from the mare the foal will often appear anxious for as long as 1 week. It is important during this time that palatable feed and fresh forage is available. Exercise is critical and separating feed and water by a short distance encourages activity.