WHITETAIL-HOLLOW APPALOOSAS and QUARTER HORSES
Foaling Gestation Chart & Vaccination Recommendations

  This is a 340 day gestation table. This is generally the normal amount of time a mare carries a foal to term. But because mares do not read books, and mother-nature does what mother-nature wants to do.....(and that's being never 'predictable')....your mare may be either a little earlier or a little later than what this chart specifys. This chart's function is to give you only a general idea of the date your mare may be ready to foal. Enjoy!

340-Day Gestational Table

Breed Date
Day 340
Breed Date
 Day 340
Breed Date
 Day 340
Breed Date
Day 340
Feb. 1
Jan. 8
Mar. 1
Feb. 7
Apr. 1
Mar. 9
May 1
Apr. 8
Feb. 2
Jan. 9
Mar. 2
Feb. 8
Apr. 2
Mar. 10
May 2
Apr. 9
Feb. 3
Jan. 10
Mar. 3
Feb. 9
Apr. 3
Mar. 11
May 3
Apr. 10
Feb. 4
Jan. 11
Mar. 4
Feb. 10
Apr. 4
Mar. 12
May 4
Apr. 11
Feb. 5
Jan. 12
Mar. 5
Feb. 11
Apr. 5
Mar. 13
May 5
Apr. 12
Feb. 6
Jan. 13
Mar. 6
Feb. 12
Apr. 6
Mar. 14
May 6
Apr. 13
Feb. 7
Jan. 14
Mar. 7
Feb. 13
Apr. 7
Mar. 15
May 7
Apr. 14
Feb. 8
Jan. 15
Mar. 8
Feb. 14
Apr. 8
Mar. 16
May 8
Apr. 15
Feb. 9
Jan. 16
Mar. 9
Feb. 15
Apr. 9
Mar. 17
May 9
Apr. 16
Feb. 10
Jan. 17
Mar. 10
Feb. 16
Apr. 10
Mar. 18
May 10
Apr. 17
Feb. 11
Jan. 18
Mar. 11
Feb. 17
Apr. 12
Mar. 19
May 11
Apr. 18
Feb. 12
Jan. 19
Mar. 12
Feb. 18
Apr. 13
Mar. 20
May 12
Apr. 19
Feb. 13
Jan. 20
Mar. 13
Feb. 19
Apr. 14
Mar. 21
May 13
Apr. 20
Feb. 14
Jan. 21
Mar. 14
Feb. 20
Apr. 15
Mar. 22
May 14
Apr. 21
Feb. 15
Jan. 22
Mar. 15
Feb. 21
Apr. 16
Mar. 23
May 15
Apr. 22
Feb. 16
Jan. 23
Mar. 16
Feb. 22
Apr. 17
Mar. 24
May 16
Apr. 23
Feb. 17
Jan. 24
Mar. 17
Feb. 23
Apr. 18
Mar. 25
May 17
Apr. 24
Feb. 18
Jan. 25
Mar. 18
Feb. 24
Apr. 19
Mar. 26
May 18
Apr. 25
Feb. 19
Jan. 26
Mar. 19
Feb. 25
Apr. 20
Mar. 27
May 19
Apr. 26
Feb. 20
Jan. 27
Mar. 20
Feb. 26
Apr. 21
Mar. 28
May 20
Apr. 27
Feb. 21
Jan. 28
Mar. 21
Feb. 27
Apr. 22
Mar. 30
May 21
Apr. 28
Feb. 22
Jan. 29
Mar. 22
Feb. 28
Apr. 23
Mar. 31
May 22
Apr. 29
Feb. 23
Jan. 30
Mar. 23
Feb. 29
Apr. 24
Apr. 1
May 23
Apr. 30
Feb. 24
Jan. 31
Mar. 24
Mar. 1
Apr. 25
Apr. 2
May 24
May. 1
Feb. 25
Feb. 1
Mar. 25
Mar. 2
Apr. 26
Apr. 3
May 25
May. 2
Feb. 26
Feb. 2
Mar. 26
Mar. 3
Apr. 27
Apr. 4
May 26
May. 3
Feb. 27
Feb. 3
Mar. 27
Mar. 4
Apr. 28
Apr. 5
May 27
May. 4
Feb. 28
Feb. 4
Mar. 28
Mar. 5
Apr. 29
Apr. 6
May 28
May. 5
Feb. 29
Feb. 5
Mar. 29
Mar. 6
Apr. 30
Apr. 7
May 29
May. 6
Mar. 30
Mar. 7
May 30
May. 7
Mar. 31
Mar. 8
May 31
May. 8
Breed Date
 Day 340
Breed Date
 Day 340
 Breed Date
Day 340
Breed Date
 Day 340
June 1
May 9
July 1
June 8
Aug. 1
July 8
Sept. 1
Aug. 9
June 2
May 10
July 2
June 9
Aug. 2
July 9
Sept. 2
Aug. 10
June 3
May 11
July 3
June 10
Aug. 3
July 10
Sept. 3
Aug. 11
June 4
May 12
July 4
June 11
Aug. 4
July 11
Sept. 4
Aug. 12
June 5
May 13
July 5
June 12
Aug. 5
July 12
Sept. 5
Aug. 13
June 6
May 14
July 6
June 13
Aug. 6
July 13
Sept. 6
Aug. 14
June 7
May 15
July 7
June 14
Aug. 7
July 14
Sept. 7
Aug. 15
June 8
May 16
July 8
June 15
Aug. 8
July 15
Sept. 8
Aug. 16
June 9
May 17
July 9
June 16
Aug. 9
July 16
Sept. 9
Aug. 17
June 10
May 18
July 10
June 17
Aug. 10
July 17
Sept. 10
Aug. 18
June 11
May 19
July 11
June 18
Aug. 11
July 18
Sept. 11
Aug. 19
June 12
May 20
July 12
June 19
Aug. 12
July 19
Sept. 12
Aug. 20
June 13
May 21
July 13
June 20
Aug. 13
July 20
Sept. 13
Aug. 21
June 14
May 22
July 14
June 21
Aug. 14
July 21
Sept. 14
Aug. 22
June 15
May 23
July 15
June 22
Aug. 15
July 22
Sept. 15
Aug. 23
June 16
May 24
July 16
June 23
Aug. 16
July 23
Sept. 16
Aug. 24
June 17
May 25
July 17
June 24
Aug. 17
July 24
Sept. 17
Aug. 25
June 18
May 26
July 18
June 25
Aug. 18
July 25
Sept. 18
Aug. 26
June 19
May 27
July 19
June 26
Aug. 19
July 26
Sept. 19
Aug. 27
June 20
May 28
July 20
June 27
Aug. 20
July 27
Sept. 20
Aug. 28
June 21
May 29
July 21
June 28
Aug. 21
July 28
Sept. 21
Aug. 29
June 22
May 30
July 22
June 29
Aug. 22
July 29
Sept. 22
Aug. 30
June 23
May 31
July 23
June 30
Aug. 23
July 30
Sept. 23
Aug. 31
June 24
June 1
July 24
July 1
Aug. 24
Aug. 1
Sept. 24
Sept. 1
June 25
June 2
July 25
July 2
Aug. 25
Aug. 2
Sept. 25
Sept. 2
June 26
June 3
July 26
July 3
Aug. 26
Aug. 3
Sept. 26
Sept. 3
June 27
June 4
July 27
July 4
Aug. 27
Aug. 4
Sept. 27
Sept. 4
June 28
June 5
July 28
July 5
Aug. 28
Aug. 5
Sept. 28
Sept. 5
June 29
June 6
July 29
July 6
Aug. 29
Aug. 6
Sept. 29
Sept. 6
June 30
June 7
July 30
July 7
Aug. 30
Aug. 7
Sept. 30
Sept. 7
Aug. 31
Aug. 8

    Recommendation for Equine Vaccinations
You should consult with your veterinarian regarding a vaccination program that will provide the most benefits for your horse.

EEE=eastern equine encephalomyelitis, WEE=western equine encephalomyelitis,
 VEE=Venezuelan equine encephalomyelitis; EHV-1=equine herpes virus type;

Disease/vaccine

Foals/weanlings

Yearlings

Performance Horses

Pleasure Horses

Broodmares

Comments

Tetanus toxoid

(Note:  Tetanus Anti-toxin, often given at birth, does not invoke long term immunity in foals.)

From nonvaccinated mare: First dose: 3 to 4 months Second dose: 4 to 5 months

From vaccinated mare: First dose: 6 months Second dose: 7 months Third dose: 8 to 9 months

Annual

Annual

Annual

Annual, 4 to 6 weeks prepartum

Booster at time of penetrating injury or surgery if last dose not administered within 6 months

Encephalomyelitis

(EEE, WEE, VEE)

EEE: (in high-risk areas) First dose: 3 to 4 months Second dose: 4 to 5 months Third dose: 8 to 9 months

WEE, EEE (in low-risk areas) and VEE: From nonvaccinated mare: First dose: 3 to 4 months Second dose: 4 to 5 months Third dose: 5 to 6 months

 From vaccinated mare: First dose: 6 months Second dose: 7 months Third dose: 8 months

Annual, spring

Annual, spring

Annual, spring

Annual, spring

Annual, spring

Annual, spring

Annual, 4 to 6 weeks prepartum

Annual, 4 to 6 weeks prepartum

In endemic areas booster EEE and WEE every 6 months; VEE only needed when threat of exposure; VEE may only be available as a combination vaccine with EEE and WEE.

Influenza

Inactivated injectable: From nonvaccinated mare: First dose: 6 months Second dose: 7 months Third dose: 8 months Then at 3-month intervals

From vaccinated mare: First dose: 9 months Second dose: 10 months Third dose: 11 to 12 months Then at 3-month intervals

Every 3 to 4 months

Every 3 to 4 months

Annual with added boosters prior to likely exposure

At least semiannual, with 1 booster 4 to 6 weeks prepartum

A series of at least 3 doses is recommended for primary immunization of foals.

Rhinopneumonitis
(EHV-1 and EHV-4)

First dose: 4 to 6 months
Second dose: 5 to 7 months
Third dose: 6 to 8 months
Then at 3-month intervals

 

Every 3 to 4 months



Optional: semiannual if elected

 


Annual with added boosters prior to likely exposure

 

Fifth, seventh, ninth month of gestation (inactivated EHV-1 vaccine);
optional dose at third month of gestation.

Vaccination of mares before breeding and 4
to 6 weeks prepartum is suggested. Breeding stallions should be
vaccinated before
the breeding season and semiannually

Strangles

Injectable: First dose: 4 to 6 months Second dose: 5 to 7 months Third dose: 7 to 8 months (depending on the product used) Fourth dose: 12 months

 

Semi-

annual

Optional: semi-annual if risk is high

Optional: semi-annual if risk is high

Semi-annual with 1 dose of inactivated M-protein vaccine 4 to 6 weeks prepartum

Vaccines containing M-protein extract may be less reactive than whole-cell vaccines. Use when endemic conditions exist or risk is high.

Rabies

Foals born to non-vaccinated mares: First dose: 3 to 4 months Second dose: 12 months

 Foals born to vaccinated mares: First dose: 6 months Second dose 7 months Third dose: 12 months

Annual

Annual

Annual

Annual, before breeding

Vaccination recommended in endemic areas. Do not use modified-live-virus vaccines in horses.

Potomac Horse Fever

First dose: 5 to 6 months Second dose: 6 to 7 months

Semi-annual

Semi-annual

Semi-annual

Semi-annual with 1 dose 4 to 6 weeks prepartum

Booster during May to June in endemic areas.

Botulism

Foal from vaccinated mare: 3 dose series of toxoid at 30-day intervals starting at 2 to 3 months-of-age

Foal from non-vaccinated mare: see comments

Not applicable

Not applicable

Not applicable

Mares should be vaccinated at eight, nine, and 10 months gestation.

Only in endemic areas. A third dose administered 4 to 6 weeks after the second dose may improve the response of foals to primary immunization.

Foal from non-vaccinated mare may benefit from: 10 toxoid at 2,4 and 8 weeks-of-age; 2) transfusion of plasma from vaccinated horse; or 3) antitoxin. Efficacy needs further study.

Equine Viral Arteritis

Intact colts intended to be breeding stallions: One dose at 6 to 12 months-of-age

Annual for colts intended to be breeding stallions

Annual for colts intended to be breeding stallions

Annual for colts intended to be breeding stallions

Annual for seronegative, open mares before breeding to carrier stallions; isolate mares for 21 days after breeding to carrier stallion

Annual for breeding stallions and teasers, 28 days before start of breeding season; virus may be shed in semen for up to 21 days. Vaccinated mares do not develop clinical signs even though they become transiently infected and may shed virus for a short time.

Rotavirus A

Little value to vaccinate foal because insufficient time to develop antibodies to protect during susceptible age

Not applicable

Not applicable

Not applicable

Vaccinate mares at 8, 9 and 10 months of gestation, each pregnancy. Passive transfer of colostral antibodies aid in prevention of rotaviral diarrhea in foals.

Check concentrations of immunoglobulins in foal to be assured that there is no failure of passive transfer.

West Nile Virus  

 

 

Annual, spring

 

 

Annual, spring Annual, spring  

Initial dose followed by a second dose in 3-6 weeks with semi-annual or annual boosters.

A third initial dose is ONLY needed if the second booster dose was given after the 6 week period following the first dose. This dose should also be given in the 3-6 weeks period.

Have vaccine series completed
at least one month prior to the mosquito season

EPM   Annual, spring Annual, spring Annual, spring   Initial dose followed by a second dose in 3-6 weeks with semi-annual or annual boosters.