I actually prefer late foals. Here in South TX mares can cycle year round.
Doesn’t seem to make any difference in the part of Australia where I live. I hate having summer foals when the weather is 40C+ and winter foals when it is wet and windy but the conditions aren’t extreme to healthy horses, just inconvenient and rough on people. But we generally foal in early summer. Late fall after the rains isn’t too bad but the mares need more feeding over winter if they are nursing.
I found that having April or early May foals is the ideal situation.
My mare is miserable in the heat, so foaling in April means that the foals is already close to 2 months-old when we hit most of the higher temperatures and she is in good condition. As well, the foal is at a decent age for fall inspections.
Plus, if the mare doesn’t have a foal at side at conception, it means she can be ridden pretty much all the spring/summer/fall season without any issue before taking a rest in the winter.
I couldn’t imagine having my mare in foal through the summer heat…
[QUOTE=PNWjumper;7215266]
OP, your note about the disadvantages ring true to me as a young horse buyer (not breeder). I don’t want to even look at foals born late in the year. Sets them up to not be synced with the Young Horse classes (Young Jumper, for my horses). I have a late July baby, and I felt that as a 4yo and even into his 5yo he was at a disadvantage to those born in the March-May time frame. My latest youngster was born in May, and my goal moving forward is to find springtime (not summer, let alone fall) babies.
It all evens out as they get older, but a horse would have to be pretty darn nice to make up for the (even minor) disadvantage early in the show career.
With the young horse classes growing in most areas, I’m actually surprised there isn’t more of a movement towards earlier babies.[/QUOTE]
My trainers ride a lot of fall youngsters in the YJC classes and they have all done just fine. 
The classes start at 5 year old, so not like AQHA or TB racing where they are starting at 2yo. By five, it’s not such a big deal, but if they are immature, you could just wait until the 6yo classes.
My mentors (Arabian breeders) were in central Illinois and bred for fall foals to cut down on the possibility of Rhodococcus equi. We’re not big into things like futurities so it didn’t matter when the babies showed up as long as they were healthy and had the best possible chance to stay that way.
We had a foal born this year August 24th (not planned to be so late) but actually I think its a great time to foal out. My colt is happy and healthy out in the fields with no flies, heat or humidity to contend with. He is already growing his winter coat and does not mind the cooler mornings and evenings. We do not show our weanlings on the line anymore until they are yearlings so the late birth does not affect that whatsoever. And with the very hectic riding show schedule in the spring and summer months trying to arrange coverage for foaling mares in the past while we are away at the shows has been a huge problem. In the late summer and fall most of the shows are wrapping up and that provides me the time to be here. I will most definitely be planning my foaling dates to be August or September for the foreseeable future I think.
