It seems I’ve written a lot this calving season (a lot too
much, you may be thinking) about calving out heifers.
Well, here’s a bit more, and hopefully the last of it for a
while.
We’ve had an up and down heifer-calving season on the EJE
this year. Of course, when compared to the “olden” days, when replacement
heifers were routinely bred to herd bulls and even the mention of “calving out
heifers” brought an involuntary shudder from everyone at the coffee table in
the local café, it’s been a delight.
In an historical context, our 2012 heifer calving experience
has been delightful. That’s due in part to the modern practice of
breeding first-calf heifers, either naturally or through artificial insemination,
to “calving ease” or “heifer” bulls. Bulls whose EPD’s (expected progeny
difference) show a statistically significant probability of expressing a
calving ease trait in their progeny. In non-ranching jargon, bulls who are
expected to sire calves which birth easily.
But what would have been a delightful experience 20-30 years
ago was up and down this year. It wasn’t a train wreck, mind you, we saved all
the calves and only had to pull one. Along the way, though, we lost a brand-new
mama cow. When you add up all the cost factors associated with raising a
replacement heifer, it’s no exaggeration to say that that one dead heifer cost
us close to $3.000. And that’s a down, whether it’s 1982 or 2012.
A day-old calf out of a crossbred black first-calf heifer and Lowline Angus bull. |
Last summer we exposed our heifers to a pair of mature Lowline
Angus bulls. Their progeny were expected to be small – around 70 lbs at birth –
and conformationally formed for ease of passage through the birth canal.
Calving ease isn’t all about low birth weight. And since the bulls were
purebred Angus, their calves were expected to be black.
The group was carefully segregated in a nice pasture six
miles from the home place and at least two miles – with multiple stout,
well-maintained fences in between – from the nearest cow herd.
Nevertheless, at least three neighbor bulls came visiting.
So early this calving season we had a couple of big calves
born to heifers. One was born naturally, a big, ugly-gray bull-calf. The other
was a black heifer calf with an enormous, blunt head. This one required
assistance. The pull wasn't very difficult once the head was out, but the young
mama cow had used up most of her energy trying to push that big, square head
through an oval opening. Then she hip-locked, requiring a bit of tricky
manipulation.
Both calves weighed in excess of 120 pounds at birth, and
bearing such big calves took quite a toll on each heifer, though both seem to
have recovered well.
Last week, after most of the remainder of the heifers had
produced a steady stream of easy-birthing little black calves, a pair of
tail-end-charlie heifers produced enormous, 130 pound-plus, red bull calves.
Sheesh! Both heifers birthed without assistance, but it was nip and tuck for a
while.
Needless to say, extended parturition digs deep into the
dam’s energy reserves and hard labor, or dystocia, slows both breed-back time
and breed-back conception rates.
We got four big, growthy calves out of the deal so it’s not
as if there’s no up-side, but only time will tell if we’ve spent 12 grand on
good replacement herd cows or on culls.
This business is an ongoing series of learning experiences.
It always has been, and it always will be. If we learn from our 2012 heifer
calving season, we’ll be ahead of the game. Only time will tell, and in the
mean time, we’ve got much to ponder, plans to make, and management practices to
execute.
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