This is the 3rd week in a row that none of my mares or geldings died. Only stallions died.

I have over 3000 geldings alone, so several of them die every week. This never happened before.

Could this be a bug?

Yeah, if you look at the search, there's a few 28 year olds and a 29 year old.

could it have something to do with the senior feed?

I've had the same problem and it's racking up my rider bill, since I normally reshuffle the newly leveled horses to the riders that have spots free from the old horses dying. Now I disproportionately have to hire new ones, because the others still have all their horses assigned. I did buy some senior feed, but only for my WWW boy Alebrije. And it's sad that only stallions die since I'm more sentimental about those than when it comes to random show mares.

I have some mares that are getting old. At this rate, I might as well FR them. I haven't used senior grain at all.

I have mares that died? I had one die this Monday actually. She was 21

Current Oldest Horse in Game: 29452608

Age: 29

It seems a few people had mares die too.

but for me this is the 5th week in a row without any dead horses today...

I also haven't had any horses die on any of my accounts.

Today I had one mare pass away - but for my intention I have way too many old horses compared to the past 10 gameyears.