Producers view feed costs as most Canadians view winter: something to complain
about that never goes away. While we do get a short break from winter each year,
feed costs are a constant, which explains the abundance of research on how to reduce
that expense. What makes a recent study unique is that it looked at feed in relation
to other factors on farm, with some surprising results.
“We have previously shown that feeding low, constant net energy (NE) diets to
grow out hogs resulted in greater revenue than feeding higher NE levels,” said Dr.
Miranda Smit, Technical Writer/Research Assistant in the Livestock Research Section
at Alberta Agriculture and Forestry.
The catch is that pigs must be able to increase feed intake to compensate for the
lower dietary energy density. That can be easier said than done in a setting where
they may face crowded pens and/or less feeder access that could affect feed intake.
Is there a relationship among dietary NE level, stocking density, feeder space and
sex? If so, what is it? The only thing researchers love more than questions are
answers, so they went seeking some with a study of 960 barrows and 960 gilts.
“Pigs were housed in 96 pens by sex - 18 or 22 pigs per pen – and fed either a low
NE (2.2 Mcal) diet based on wheat/barley or a high NE (2.35 Mcal) diet based on
wheat and field peas with some canola oil. Half the pens had two feeder spaces and
the other half had three. Pen body weight and feed disappearance were measured
for each growth phase.”
Though the results confirmed previous findings on some fronts, they also offered
new insights of interest to producers.
Eat more, grow the same?
“Once again, we found pigs on the low NE diet consumed more feed than those on
the high NE regimen, without really changing growth rate. For stocking density, the
18 pigs per pen ate a bit more than those
with 22 per pen and also had better growth rates, as overcrowding means pigs
have fewer chances to eat and generally don’t grow as well.”
Adding an extra feeder in a pen did result in pigs eating more, yet the difference in
average daily gain was negligible.
“My best guess is that the added feeder raised the chance of feed being spilled.
When you look at feed efficiency, it went down a bit with the third feeder as there
were now three places where feed could be spilled. Pigs in those pens probably ate
a bit more but spilled more feed as well.”
For Dr. Smit, the biggest surprise in their findings was what didn’t happen.
“I expected to see interactions for feed intake among three different things: stocking
density, feeders and diet. In actuality, we saw no relationship between those parameters.
What was neat to see is that regardless of whether you overcrowd your pigs
or give them an extra feeder, you can use low NE diets and the pigs will do quite well
with it. That was an interesting take away, as when we saw in previous trials that low
NE diets worked and lowered feed costs, we assumed all the other factors had to be
right for that to happen; but this study suggests otherwise.”
Though this project is further confirmation that diets based on low net energy valueSource : Swine Innovation Porc
can save on feed costs, it’s important that the ratio of amino acids to energy isn’t
substantially altered or results will not meet producer expectations. For those considering
such a diet, Dr. Smit urges them to consult a nutritionist before taking the