• If you are having problems logging in please use the Contact Us in the lower right hand corner of the forum page for assistance.

Ranchers.net

I am starting to make plans on when to breed my heifers to calve in 2011. Been reading some articles and discussions on when to schedule heifers vs when you schedule the cows. We've been doing the young cows (1st & 2nd calf) 2 weeks before the cows - the bulls go out w/ young cows June 10, cows June 24. I had read something about the later heifers breeding back quicker than the early ones, and how that goes against the conventional wisdom of giving the 1st calvers a longer time to recover and breed back. I noticed the other day the nice baldy 3 yr old I have that was the first to calve last year (march 7), and she isn't even bagged up yet. So I did a little statistical analysis on my own herd, using the past three years' data.

I split the herd into 4 groups based on when they calved as heifers. A group was first, B second, ect. I counted the days between their first calf and second calf. Then I averaged each group's calving interval, calving date as a heifer, and calving date as a 3 yr old. Here's the results.

'07 1st calf heifers
Group A - avg '07 calving date - march 22
avg '08 calving date - april 2
avg calving interval - 377 days

Group B - '07 - march 28
'08 - april 7
interval - 375 days

Group C - '07 - April 8
'08 - April 2
interval - 362 days

Group D - '07 - april 25
'08 - april 5
interval - 346 days

The next year's data showed the same trend. Intervals were 386 for group A, 381 for B, 369 for C, and 364 for D. (it was a long, cold spring)

The thing that blows me away here is how things average out. As 3 yr olds, each group's average calving date falls in a 5 day window (April 2-7) no matter when they calved as 2 yr olds.

Has anyone else seen this happen in your own herd? If so, have you changed your breeding schedule?

Here's my interpretation of what this means. Green grass is better than good alfalfa hay and expensive lick tubs at getting cows to breed back. I'm interested to hear what everyone else has to say about this topic.
Top