Filly or Colt?

[klasqh]

Any experience on the percentage of fillies to colts when the mare is early or overdue? Most cattle people say a cow that goes late will have a bull calf - early is a heifer. What is most common in the horse world?

[karenkarenn]

the filly that we had before she was sold went 10 days over.

[Crystal]

At 80-90 days you can fetal sex and again at 125 days.. it's a little early then to determine approx over/under days ..

[LB]

Conventional wisdom says that the gestation for a colt is longer than that for a filly, but I've never found that to be true with my own mares and foals (obviously a limited sample.)

[winds]

Our mare has had 3 foals up to this year. She was early for 2 of them and they were fillies. She was over due for the other and it was a colt. This year she was over due 8 days, thought we were going to have a colt again, dang if she didn't have a filly. Made a liar out of me. So who knows!

They'll drive you CRAZY! LOL

winds

[Zahrah]

At 80-90 days you can fetal sex and again at 125 days.. it's a little early then to determine approx over/under days ..

Around 60 days too.

[casallc]

On average mares carry horse colts 6 days longer than fillys. At least that was the figure 30 years ago when I was at Colorado State (no reason it should change).

Thare is no such thing as a mare due date (they will have them when they get ready).
Mare gestation time:
319 Days or fewer: 4.43%

320-326 Days: 7.14%

327-332 Days: 7.96%

333-338 Days: 9.94%

339-344 Days: 15.05%

345-350 Days: 12.76%

351-356 Days: 8.86%

357-362 Days: 5.98%

363-370 Days: 8.51%

371 Days or greater: 19.37%

of 3794 mares reported in study: http://www.equine-reproduction.com/arti ... rdue.shtml