D2—Lancaster Farming, Saturday, October 20,1984
NEWARK, Del - Biotechnology Delaware extension livestock
has given the pork industry some specialist Dr. Ken Kephart
useful management tools, and suggests producers take a hard
several more are on the way. But look at their present operations to
instead of waiting for tomorrow’s see if they’re making good use of
research results, University of knowledge that already exists.
Perk Prose
■<«. < «*»
“Over there’s a sow that just
weaned her third litter. She had
nine pigs but raised only six. She
weaned eight pigs each with her
last two litters. Is it time to send
her down the road? ’ ’
“And there’s a gilt that farrowed
seven pigs but only raised five.
What do I do with her?” Have you
ever asked yourself questions like
these? Just when is the right time
to cull a sow?
That’s an age-old question that
brings a different answer every
time it comes up. The bottom line,
of course, depends on why you’re
thinking of culling the sow.
If she’s injured or has severe feet
and leg problems, the decision is
easy. She’s got to go.
If she won’t cycle or settle,
there’s also little sense in keeping
her. But how long do you wait? If
she isn’t cycling, take a look at her
condition. Sows in very thin flesh
after lactation, especially first
litter sows, are often slow to come
back into heat. So they deserve
some time to catch up. A month is
reasonable. That gives them at
least three weeks since their last
expected heat.
For those that cycle, but don’t
settle, most producers will breed
twice before culling. That figures
out, again, to roughly one month
or $l2 to $l5 infeed.
What about disease? If the sow
has had a miserable case of MMA,
many herdsmen won’t think twice
about sending her to market. That
may be the logical thing to do. But
if you talk with the folks who
research this mastitis problem,
they’ll say you might be just as far
ahead to keep the sow around.
Sure, some lines of sows seem to
have a predisposition to mastitis.
But many of the mastitis cases we
see are not the sow’s fault.
And that way of thinking is true
for some other diseases like Lepto
and Parvovirus. Just because a
sow’s litter is affected at this
farrowing doesn’t necessarily
mean she’ll have a problem the
next time around.
What about performance?
Where should you draw the line?
Some people will tell you there’s no
sense in drawing a line. Dr.
Technology no substitute for good management
Kenneth B. Kephart
Extension Livestock Spec.
University of Del.
Maurice Bichard of PIG (the Pig
Improvement Company) contends
in a recent article that the
repeatability of sow performance
is too low to justify culling on that
basis.
He’s probably right, for several
reasons. Take this issue of
repeatability and apply it to our
first-litter gilt that raised five pigs.
And we’ll put her up against
another gilt that you’d surely want
to keep one that weaned nine
pigs. The difference in litter size
between the two is four pigs. With
the first litter (a single record), the
repeatability for litter size at
weaning is about 0.16. So the dif
ference we would expect to see the
next time around would be 16
percent of four pigs (0.16x4=0.64)
not even one pig.
Repeatability is telling us that,
on the average, with the next litter
the good gilt will wean .64 more
pigs than the poor gilt. The dif
ference is so small because there
are so many things that affect
litter size besides genetics.
If you’ve got more than one
record, repeatability does get
bigger. For example, the dif
ference in litter size between two
sows is nearly 50 percent
predictable if they’re on their fifth
litter. But waiting for five litters to
go by is a pretty long time to come
to a decision.
Another sad fact of genetic
selection is that the more you cull,
the younger your sow herd
becomes. Everyone who has pigs is
fully aware that gilts have smaller
litters than sows. So any im
provements you try to make in
litter size will be hampered by a
higher percentage of gilt litters.
The bottom line to improving
litter size at weaning is that you’ll
make little progress through
genetic selection. A safer bet is to
crossbreed for heterosis and keep
the sow for at least three litters,
the parity at which production
seems to be maximized.
If you’re still convinced you
should select for litter size, then
focus on your replacement boars.
There are fewer of them and they
account for half of your genetic
base.
October is Pork Month
LIVESTOCK
LATEST
y/fl
I. .. ■
A
4j
In the future, the specialist
predicts, scientific breakthroughs
in genetic engineering
recombinant DNA may make it
possible to grow more and better
hogs faster on less feed.
Scientists using gene splicing
may be able to produce vaccines to
keep pigs healthier; growth hor
mones to radically improve growth
rates and feed efficiency while
yielding leaner, meatier car
casses; and synthetic amino acids
to replace expensive soybean meal
in rations. They can already take
embryos from high performing
sows and plant them in recipient
sows, just as the cattle industry
does.
Artificial insemination is
another available technique,
though it hasn’t yet caught on to a
great extent in the hog industry,
Kephart says. Most find
it impractical to breed artifically
on a large scale, but a lot of folks
are using A.I. to breed their best
sows. By selecting replacement
gilts and herd boars from these
offspring, producers can close
their herds, which is a big step in
preventing disease transmission.
Sophisticated technology alone
won’t improve performance,
Kephart says. He offers the
following suggestions to help
producers improve current
management practices:
• Keep good records. “Total
herd feed efficiency, breeding
Meadow M
LOYSVILLE Buyers from
nine eastern and mid-western
states converged on Loysville’s
Meadow Mist Farms on Wed
nesday, Oct. 10, for a dispersal of
mature Angus cows conducted by
the farm’s owner, Dr. Burleigh
Anderson.
“We had quite an active sale,”
said the well-known veterinarian
and Angus breeder, whose 107 lots
brought $133,400, for a sale
average of $1,247 per head. The
three top selling females sold for
$7,900, $5,800, and $5,700.
Auctioneered by Mike Jones, the
sale featured daughters of
Schearbrook Shoshone, Ankonian
Dynamo, PS Power Play, Bon
View Winston 1342, Big Moose,
Lucan of Wye, Band 174, and
Meadow Mist Magnum.
“We’re starting all over again
with 87 heifers,” said the veteran
cattleman who began breeding
Angus cattle 23 years ago. Since its
beginning, Meadow Mist Farm has
maintained a completely closed
herd.
Anderson, who owns a total of 18
bulls m partnership, reports that
most of his heifers are currently
being bred by Meadow Mist bulls.
“The one we’re most excited
about is Meadow Mist Sunnder
350,” says Anderson, adding that
the bull has had cattle bred to him
from California to Maine.
An advocate of performance
testing, Dr. Anderson has par
ticipated in Ohio, Pa., and W. Va.,
bull test programs, and currently
<«*
Using performance tested boars is one good way to im
prove herd performance.
records, conception rate, number
weaned, weaning weights and post
weanmg rate of gam are just a few
of the things you should be jotting
down,” he says. Use these records
to spot problems and make
decisions. If the numbers are too
overwhelming for pencil and
paper, a computer might help.
• Use performance-tested
breeding stock. “Buy boars on the
basis of looks and performance.
Know how well the pigs do on your
farm,” he advises. “Then bring in
the blood lines that will do even
better.”
• Make solid efforts at*
marketing. “Look at all the
ist holds Angus dispersal
has 15 bulls on test in W. Va. In
1982, Meadow Mist had the highest
PRODUCERS^
(WE SM.OTE YOU I
i -i
markets in your area. Consider
grade and yield programs. And sell
your pigs when the time is right,
not just when it’s convenient.”
• Keep pigs healthy and com
fortable. Mange, overcrowding,
heat and cold stress can all cost a
lot of money. They’re also factors a
producer can at least partially
control.
"In short,” concludes Kephart,
“tomorrow’s technology will offer
a level of performance that our hog
industry has never seen. But it will
be useless without good
management and attention to
detail.”
indexing bull in the 10-year history
of the Penn State test station.