For years I have looked in every mare care book I can find and when it comes to figuring out when the mare is due I might as well save my time. Due dates are only for people. I know my mares never seem to be watching the calendar.
Do the mathh then cross your finders. Normal gestation is 340 days.
Or, my favorite......
When your mare can't hardly fit through the stall door and she blinks those sleepy eyes at you during yet another late nite check, just go to the market the next day for a quick gallon of milk and you can bet there will be a beautiful new addition awaiting you. Of course your mare just looks at you like the cat that ate the cream. You know the look, the one that says..........."what?"
Personal Note... When Garbosa was due with Pacifico NW I was on mare check. Having spent the day outside I brought her in, she seemed uncomfortable, nothing new there she was over due according to the books. Happy to start eating dinner, settled down to eating her hay. My favorite book had suggested expressing some milk into your hand to check it's color for approx delivery time. There I was looking at the small puddle in my palm and asking a friend "Do you think they meant 1% or 2?" When all of the sudden her water breaks and Labor had begun. I guess Garbosa just wanted friends around to give support. The more the merrier as friends from across the street came in and a video camera was grabbed. Soaked up all the attention she was getting and was so proud to share the newest addition to the barn.
Treatment of mares within twelve hours of foaling with an oral ivermectincan prevent the development of certain intestinal parasites in their foals. Another concept that bears thinking about is the use of daily dewormers for pregnant and lactating mares. Recent research has shown that the daily use of dewormer pyrantel tartate* essentially breaks the lifecycle of many intestinal parasites and before the eggs can be shed in the mares milk and infect a nursing foal.