Energy Shortage In Feed Hurts Gain

By DON STONEMAN

Show the door to feed salesmen recommending protein
supplement programs without checking the level of
energy in a beef ration, said Mark Cameron, animal
nutritionist, Ralston Purina to Waterloo cattlemen
recently.
The latest research shows that cattle don't grow as
well as they should on diets where protein and
energy are mismatched. This means they spend
unnecessary days on feed. Cattle may also not show
the growth patterns that are best for the carcass
weights that are desired.
"We have the best genetics in North America. We
aren't always feeding it to best advantage,"
Cameron said.
He blames part of that on outdated standards that
are often used to develop feeds for livestock. The
National Research Council (NRC) standards don't
take 25 years of genetic improvements into account, 
Cameron said. New feed additives, growth
stimulants, better nutritional knowledge and
improved management skills also make the old rules
obsolete.
Some of the nutritional knowledge relates to
energy-protein interaction. When energy is
elevated, protein must be elevated as well. "The
key is, (cattle) will grow, regardless of what they
do." But they won't grow as well as they should.
Cameron recommends borrowing a page from the pig
feeder's book. Phase feeding, pumping more energy
into them when cattle are young - before they weigh
1,000 pounds - will boost average daily gain
through the entire feeding period.
Cameron sees studies from the U.S. that show
high-lysine corn boosts cattle gains. Lack of the
amino acid lysine limits muscle development.
"You guys have it made in Ontario. You have lots of
energy" to put into cattle diets, Cameron said.
"There is tons of new information out there and no
one is using it."
Corn silage may be eight to 10 per cent protein,
while cattle need 14 to 16 per cent to get top
growth. The NRC recommends 10 per cent protein in
the diets of finishing cattle. "That is a joke,"
Cameron said. There are new NRC recommendations on
the way, but they still lag since they are based on
research conducted between 1984 and 1990.
"Some people in Ontario say Revealor-S doesn't
work. I believe it doesn't work because they don't
have enough nutrition," neither energy or protein,
to feed continental crossbred cattle, he said.
The old diets are probably good enough to feed out
Herefords, but they won't put that extra 0.3 to 0.4
pounds of gain a day on growthy crossbreeds.
Just like feeding dairy cattle, dry matter intake
is important, Cameron stressed. He quoted a study
in the U.S. that showed that four inches, eight
inches and 12 inches of mud in a yard reduced dry
matter intake by an average of 15, 22 and 30 per
cent in feedlot cattle.
There's also a "shiver factor," that isn't
accounted for in NRC standards, he said. In cold,
wet weather, cattle need still more energy to
offset losses to maintain body temperature.
There should be a swing away from full-feeding
cattle. The trouble with simply filling the bunk
every day is that cattle's intake swings up and
down over an eight-day cycle like "a roller coaster
ride."
"The key is to make this a little roller coaster
ride, not a big colossal one."
Cameron cited a U.S. study where cattle on full
feed gained an average 2.07 pounds per day compared
to cattle on a managed diet which gained 3.78
pounds because their intake was consistent. The
gain to feed ratio was one to 5.35 pounds compared
to one to 9.53 pounds. 
Don't let the bunks go empty or cattle will slug
feed and make themselves sick, he said. "They will
go to subclinical or full-blown acidosis very
quickly."
While it is still true that cattlemen make or lose
money the day they buy cattle, average daily gain,
feed costs, trucking, processing and yardage are
all factors in making a profit. This becomes more
important as corn prices rise to $140 a tonne.  

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