Pastures life span (Animals disappearing from Pastures)

I have found a number of players asking why their cows gone. Many discussions are related to infestation. If your livestock still keep disappearing, consider your animals have life span issue.
Especially when you starting your new town on easy mode, the families come with a herd of livestock. Then you will have a livestock life span shortage to worry about.

Sterilize Period

Your new town come with cattle and young cattle.

At second year, all cattle are grown up.
At sixth year, if you still haven't build any pasture, the first cattle is disappearing. And soon you're going to lose them left and right, because the animals are too old. (I'm the one who luckly enough to building my first pasture at sixth year, the perfect time to see your cattle dying out. At first, I was thinking it's a bug.)

Prevention

A. Build your first pasture before the fourth year, grazing the cattle. (I haven't test the sheep and chicken, suggest that they have shorter life span.)
B. If you are too late, build the pasture then have your herdsman slaughter all cattle for meat. Then import cattle with trading post later.
C. Don't let your livestock sitting in trading post too long, they will keep aging.

Perfection

Instead of growing your first herd of livestock until pasture is full. I suggest that you grow and slaughter some of them for meat first. Because your herdsmans might taking the old livestock that's going to expire anyway. Although, herdsmans randomly slaughter mature livestock, they aren't slaughter young livestock first.

Special Thanks

'ebrumby' have say that Livestock have a lifespan and the like.
Ring me the idea to test the lifespan, and build pasture early in the game.
Thus, ending the long torture period, not knowing while my cows, my sheeps keep disappearing.

[maiden4meldin]

For me, when I have an easy mode start, I build a pasture by year two. But, I play homeless for five years. building only one house per year until everyone is housed. Helps me to get a better handle on the food situations. Also, I play homeless first five years, because I school my people from year one. So I combine those two into the slower start. Meaning, I do not require as much food as my people eat from the barns.

So I never really thought about the lifespans of pasture animals. lol. I always build my first pasture on open ground, and keep it small, as I want meat/leather as quick as possible. When I have a pasture as an early start, I do not build a herdsman