Mare & Foaling Guide
Pre-Partum
Nutrition requirements are similar to non-pregnant mares in the first and second trimester,
monitor body condition and adjust feed amount/quality accordingly. In general, second cut hay
is higher in protein than first cut, and alfalfa has the highest amount of protein. Grain is not
necessary unless a difficult keeper. I always recommend an equine supplement containing
selenium (island horse supplement, equine super diet by equestro) and a free choice salt block.
In the third trimester, mares should be fed 1.5-2% of their body weight per day (hay/grain)
Deworming should be done at least once prior to the third semester. Avoid the use of
dewormers in the last 30 days of gestation. Fecal egg counts may be used to help guide
deworming frequency. High shedders (>500 eggs per gram) will need more frequent
deworming. Mares should be dewormed immediately after foaling with Ivermectin to reduce transfer of Strongyloides westeri to foals.
Mare Vaccination
1. EHV-1 (Pneumabort K/Prestige II/ Vetera 2XP)-3, 5, 7, 9 months
2. 6 way Vaccine- 4 to 6 weeks prior to foaling
If previously unvaccinated, 6 way vaccine at 8 weeks prior to foaling and a booster 4
weeks later
Housing
Pregnant mares should be moved to their foaling facility 2-4 weeks prior to foaling to allow
them to acclimatize and develop antibodies to local pathogens that will get passed on into the
colostrum.
Check for Caslick (vulvoplasty) and remove 1-2 weeks before due date
Screen for Neonatal Isoerythrolysis- Only a risk for multi-parous mares (maiden mares low
risk). Mares who lack the Qa or Aa blood group factor should be identified as mares at risk.
Average gestation length is 340 days ( 372-374 days in donkeys)
Foaling
Clean, dust free pen filled with straw is ideal.
Approximately 80% of mares foal between 11pm –4am
Stage 1 of Labor: Restlesness, mild colic signs, tail swishing, sweating typically l
asts 1-4hrs
Stage 2 of Labor- At the onset of foaling, the water breaks and a thin, transparent
greyish-white membrane (the amnion should be protruding), active straining Foal
should be born in approximately 5-20 minutes from here
Stage 3- Passage of Placenta 1-3hours. If all of the placenta has not been expelled
by 3 hours after foaling, this is an emergency and requires immediate
intervention. Retained placenta can cause sepsis and laminitis very quickly
“Red Bag”- Premature placental separation, this is an emergency and must be cut open
immediately and foal should be delivered as quickly as possible
Post-Partum
Deworming- Mare should be dewormed immediately using an ivermectin product for
treatment of strongyloides westeri (passed in milk to foal)
Check udder patency of teats (visually), colostrum should be thick and sticky either yellow or
grey-tinged
Normal body temp of foal: 37.2-38.7C
Colostrum specific gravity >1.06 or if using a sugar/Brix refractometer >23% or if using an
alcohol refractometer >16%. These values correlate to colostrum greater than 600mg of IgG/dl
Newborn foal navel should be dipped (complelety submerged) in 0.5% chlorhexidine solution
immediately after umbilical cord has seperated, and again in 4-6 hours.
Foal should stand within 1 hour, Nurse within 2 hours, and meconium passed within 3 hours. If
meconium has not passed use a warm water enema (60mls) or fleet sodium phosphate enema
warmed to body temperature
Check for contracted or laxity in tendons.
“Foal Heat Diarrhea” may occur between 5-15 days old which is associated with changes in
microflora in digestive system. Generally self-limiting and lasts 3-7 days. Attitude, temperature,
and appetite should all be normal. Infectious causes of diarrhea also possible.
Foals should be dewormed at 2, 4, 6 months of age with Fenbendazole (safer slower die off) and again prior to weaning. At 9-10 months treat for tapeworms and bots after the first heavy frost (using Ivermectin/Praziquantel)
Foal Vaccination guidelines
1st dose –4-6 months
2nd dose- 4-6 weeks later
3rd dose- 10-12 months old
We recommend 6 way vaccines (Flu/Rhino/Tetanus/EEE/WEE/West Nile)
**there was a confirmed case of West Nile Virus in a horse in the North Thompson Valley in Nov 2025 **
