Equine Equine ReproductionReproductionGestation and parturition in Gestation and parturition in

MaresMares

Gestation In MaresGestation In Mares

Duration of gestationDuration of gestation 11 months , 5 days11 months , 5 days Range 335-342 daysRange 335-342 days Can be as short as 305 days and as Can be as short as 305 days and as

long as 400 days.long as 400 days.

Foals are not normally capable of Foals are not normally capable of extra uterine survival until day day extra uterine survival until day day 300 of Gestation300 of Gestation

Gestation in MaresGestation in Mares

Gestation Length are affected byGestation Length are affected by BreedBreed

SeasonSeason Sex of the foalSex of the foal

Age of MareAge of Mare TwinningTwinning

Dam and SireDam and Sire ManagementManagement

DiseaseDisease

Gestation in MaresGestation in Mares

BreedBreed Shorter in TB and SB (325-340 days)Shorter in TB and SB (325-340 days) Draft horses (330-340 days)Draft horses (330-340 days) Crosses (350-375 days)Crosses (350-375 days) SeasonSeason Mares bred in late winter and early Mares bred in late winter and early

spring have gestation lengths on spring have gestation lengths on average10 days longer than those bred average10 days longer than those bred in the summerin the summer

Gestation in Mares Gestation in Mares Management of Pregnant Management of Pregnant

MaresMares Confirm pregnancy at 42 daysConfirm pregnancy at 42 days Re examine at 150 and 210 days to Re examine at 150 and 210 days to

ensure normal progressionensure normal progression

Gestation in Mares Gestation in Mares FeedingFeeding

Adequate and balanced dietAdequate and balanced diet Increase in the last 3 months enough Increase in the last 3 months enough

to increase maternal body weight by to increase maternal body weight by 15%.15%.

Excessive feeding can increase the Excessive feeding can increase the risk of laminitis and OCD in the foal.risk of laminitis and OCD in the foal.

In the last week add laxative feed In the last week add laxative feed such as bran .such as bran .

Gestation in MaresGestation in Mares Vaccinations Vaccinations

EVR@ 5,7and 9 monthsEVR@ 5,7and 9 months

Use a killed vaccine if possible.Use a killed vaccine if possible. Tetanus 30-60 days before full term.Tetanus 30-60 days before full term. All other vaccines should be done 4-All other vaccines should be done 4-

6 weeks before foaling.6 weeks before foaling.

Signs of Approaching Signs of Approaching ParturitionParturitionMammary GlandsMammary Glands

AbdomenAbdomen

Pelvic LigamentsPelvic Ligaments

Signs of ParturitionSigns of Parturition Swelling of mammary Swelling of mammary

glandsglands Waxing as early as 4 Waxing as early as 4

days but usually 24-48 days but usually 24-48 hrs before due to hrs before due to colostrumcolostrum

Some mares bag up Some mares bag up and leak colostrum this and leak colostrum this should be controlled so should be controlled so that there is plenty of that there is plenty of colostrum for the foal. colostrum for the foal.

Changes in pre foaling Changes in pre foaling mammary secretion mammary secretion are used to determine are used to determine fetal maturity and fetal maturity and readiness for birth readiness for birth

Ca levels increase Ca levels increase dramatically when dramatically when foaling is imminent.foaling is imminent.

When Ca CO3 in udder When Ca CO3 in udder secretion reaches secretion reaches >200ppmthe mare will >200ppmthe mare will foal within 72 hours.foal within 72 hours.

Four Phases of Four Phases of LaborLabor

Stage 1Stage 1

Phase 1 stage1Phase 1 stage1 RestlessnessRestlessness AnxietyAnxiety Loss of appetiteLoss of appetite Tail swishingTail swishing Kicking at her bellyKicking at her belly SweatingSweating Looking at or biting Looking at or biting

her flanksher flanks CrampingCramping Passing small Passing small

amounts of loose amounts of loose manuremanure

Lying down and Lying down and getting upgetting up

The discomfort viewed The discomfort viewed at this stage is from at this stage is from uterine contractionsuterine contractions

In the last few weeks In the last few weeks before the birth the before the birth the mare may lay down and mare may lay down and grunt every 5 seconds grunt every 5 seconds this may fool you into this may fool you into thinking she is going thinking she is going into labor however this into labor however this is a result of the is a result of the abdomen pressing abdomen pressing against the diaphragm against the diaphragm and as the horse and as the horse normally breathes at 12 normally breathes at 12 breathes per minute a breathes per minute a breath every 5 seconds breath every 5 seconds is normalis normal

As we come to the end As we come to the end of this stage a small of this stage a small portion of the portion of the placenta is visible this placenta is visible this is known as the is known as the

“ “ Cervical Star”Cervical Star”

When the cervix has When the cervix has opened wide enough opened wide enough for this to be visible it for this to be visible it will bulge and burst will bulge and burst this is the breaking of this is the breaking of the water.the water.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Stage 2Stage 2

After the water has After the water has broken the inner sack broken the inner sack (Amnion ) should (Amnion ) should advance and become advance and become visible ,this will be visible ,this will be delicate ,translucent,andelicate ,translucent,and milky white in color.d milky white in color.

The first sighn of a foal The first sighn of a foal should be one fore foot should be one fore foot with the soles facing with the soles facing down. With the second down. With the second fore foot appearing fore foot appearing withen one or two more withen one or two more contractions.contractions.

It is not uncommen for It is not uncommen for the mare to get up a lie the mare to get up a lie down during this time.down during this time.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

When the foal has its When the foal has its head and shoulders in head and shoulders in the pelvic cavity the the pelvic cavity the amniotic membrane will amniotic membrane will burst burst

Assistance should only Assistance should only be offered if it is be offered if it is abslutely abslutely necessary.Traction on necessary.Traction on the foals forelimb the foals forelimb should be in rythem should be in rythem with the mares with the mares contractions .contractions .

After the foal’s hips have After the foal’s hips have exited the the pelvis the mae exited the the pelvis the mae will ussually rest for 15-20 will ussually rest for 15-20 minutes . minutes .

CARE must be tacken not to CARE must be tacken not to disturb the mare and foal so disturb the mare and foal so that the umbiliacal cord does that the umbiliacal cord does not break prematurely ,the not break prematurely ,the mare will stand and break the mare will stand and break the cord naturealy . When this is cord naturealy . When this is done we will step in an done we will step in an adminaster oxygen to the foal adminaster oxygen to the foal . .

The umbilical stump shoud be The umbilical stump shoud be disinfected with disinfected with chlorahexadine or iodine chlorahexadine or iodine solutionsolution