How Fast Can Herd Size be Incresed

[rvm45]

Friends,

If you're following my story, you know wherefore I ask…

But if I have a herd of Beef or Dairy Cattle—or Swine…

And I use only in-house breeding…

I mean, I don't bring in any stock from outside...

Approximately how long will it take to double my herd size in each case?

I already have this question on "Quora" but I though that someone here might know.

This is a complicated question to "Google"—at least for me.

I know from Animal Science class at Purdue, that pork has a 4-year cycle, but beef has a 10-year cycle. That i to say, pigs breed faster, and the supply of pork can increase in response to an increase in demand FASTER than the supply of beef can increase.

That doesn't get me any NUMBERS!!!


…..RVM45

[papaof2]

I can't help, other than asking:
How many head can be bred each year?
What % of the total stock is that?
How long is gestation?

Those answers will give you bare numbers. Then figure in how many will be eaten by the people plus the number lost to predators/illness.

Then you have the yearly total increase, from which you should be able to work out how long to double herd size.

"In house" breeding isn't viable in the long term. You need to bring in some outside stock for genetic diversity.

[rvm45]

Friends,

In case anyone else is interested in this obscure question, I got this answer off "Quora.":

Lets see a bred cow gestation period is 283 days, bred cows from breeding % is unknown, using AI say 80 % if the technician is good. 2 - 3 years to breeding age. another 80 % and 283 days to birth, 50 % males. Death loss or culling 3 %. You have doubled the size of dairy herd milking.

Beef herd uses same numbers but natural breeding, usually 60–70 % are bred then the other 38-28% in the next heat period. Death loss or culling could be higher. 50 % males to slaughter. Doubles the female beef breeding herd.


….RVM45

And yes, they pretty much used the method suggested earlier.

EE…

About inbreeding—You can indulge in a great deal of Line-Breeding with livestock before it becomes a serious problem. With Cattle, get 5x or 15x the original herd size, and then bring in several unrelated bulls...

[bretf]

We never raised hogs, so I can't help you with that one. Although we did buy a few over the years to to butcher and a couple times to "rooto till" a new garden spot before putting them in the freezer.

We did have cows all the time in my younger days. Dad bred the cows every year to calve in the spring. We had them in good manageable pastures and a decent barn for the milk cow. Heifers were first bred to calve for the first time in their third spring.

We ran a bull with them and never had one that did not breed. An uncle who was a rancher and ran his cows in the mountains would sell any cows that didn't breed.

Many times over the years, Dad and I pulled a calf. Twice we had the vet do a C-section. If we hadn't closely monitored them all, we would have probably lost those calves, and maybe the cows.  We lost maybe three calves that I can remember. It is extremely rare but one cow gave twins, once.
For the cows which lost a calf, Dad went to the auction  and bought a baby for them. The cow would have nothing to do with the new calf, so Dad would partially skin the dead calf and secure the hide over the new calf. The cow was confused for a couple of days but would come around and accept the new calf.

And as your search revealed, plan on 50% bulls.

I hope this helps.