Equine - Parturition and Normal Neonate Flashcards
Typically, how long is gestation in a mare?
340 days (average is 338-343 days)
What is the average gestation length for Thoroughbred and Standardbred horses?
325-340 days
How long is average gestation in Draft mares?
350-375 days
Mares bred in late winter and early spring have gestation lengths that are on average 10 days _____ than those bred in summer.
longer
Mares with fillies foal on average ____ days earlier.
three
True or False: Mares will often carry a foal for a similar time period during each pregnancy.
TRUE
How is a due date of a mare calculated?
Approximate foaling date may be calculated by subtracting 25 days from the day the mare was bred or ovulation was detected - the date is more accurate when actual breeding or ovulation date is known
How should pregnant mares be housed?
they should be separated from other horses
How are pregnant mares managed?
Light exercise is encouraged during early to mid pregnancy, avoid stress, and routine dental and foot care is recommended to be performed following foaling and prior to breeding
When should a mare be moved to a stall prior to foaling?
7-14 days prior
What nutrition changes are necessary at early to mid gestation?
none - just make sure there is a good quality pasture or hay +/- supplement
What is the foal growth rate during early to mid gestation?
0.2 lb/day
What feed changes need to occur during late gestation and lactation?
increase the feed by 50-100% - good quality pasture or hay with grain mix supplement
What is the foal growth rate during late gestation and lactation?
1 lb/day
What should not be fed during the last 2-3 months of gestation?
fescue hay or pasture
What vaccinations should a mare get?
EHV-1, Tetanus, EEE, WEE, Influenza, WNV
When should the EHV-1 vaccination be given? What type of vaccination is it?
5, 7, and 9 months of gestation; killed vaccination (Pneumabort-K and Prodigy)
When should the Tetanus, EEE, WEE, Influenza, and WNV vaccinations be given/
4-6 weeks prior to foaling
What additional vaccinations could be given during pregnancy to a mare?
EVA, Strangles, Botulism, PHF, Rotavirus, and Rabies
What is the general recommendation for giving an anthelmintic during pregnancy?
Give a ivermectin-type anthelmintic one month prior to the anticipated due date - make sure to read the label
What is a Caslick’s surgery?
a surgical procedure to partially close the dorsal portion of the vulva
When should a Caslick’s be removed?
7-14 days prior to the predicted foaling date
What happens if a Caslick’s is not removed?
Dystocia and/or serious injury to the perineal region of the mare
When do relaxin levels rise, what produces it, and what to rising levels of it do?
The placenta produces relaxin and levels rise in the last 1/2 of gestation. It causes vulvar elongation and ischial (tail head) sinking
What is prolactin produced by, when do prolactin levels increase, and what changes does it influence?
It is produced by the hypothalamus 4-6 weeks before foaling and influences mammary development
What is oxytoxin produced by, when is it produced, and what does it influence?
It is produced by the pituitary at the time of foaling (Fergusen’s reflex) and influences milk letdown
When you see waxing on a mare’s mammary glands, what does that indicate in relation to when parturition is?
She will probably foal in 1-2 weeks
What will happen to K and Na levels in the milk 24-48 days prior to foaling?
K increases and Na decreases
What happens to Ca levels 24-72 hours prior to foaling?
they will increase
What can be used to measure monitoring foaling pre-partum?
Tocodynamometer - it is not common, expensive, and not practical
What initates parturition?
Fetal stress - an increase in fetal CRH may trigger a shift in placental steroidogenesis from progestins to estrogens which will increase uterine contractility and relaxin production
When does fetal plasma cortisol rise prior to parturition?
48 hours