The Rural Voice, 2002-05, Page 581
' Research Scrap Book
Ammonium may be the fertilizer of the future
The growing levels of carbon
dioxide in the air could mean farmers
in future will use ammonium fertil-
izers instead of nitrate fertilizer, says a
University of California study
published in Proceedings oldie
National Academy of Sciences.
The high atmospheric carbon
dioxide level will interfere with
plants' ability to used nitrate fertilizer,
says Arnold Bloom, a plant physio-
logist with the university. However
ammonium fertilizer will continue to
work well, boosting protein levels in
wheat by 73 per cent.
"We've known for some time that
increasing concentrations of CO2 does
boost plant growth rates ipitially,"
Bloom said. In laboratory experi-
ments, plants initially responded to a
doubling of CO2 levels by
assimilating 30 per cent more carbon,
but within a few days, this dropped
back to just 12 per cent greater than
normal.
Atmospheric monitoring since
1800 indicates that CO2 concentrations
have risen more than 30 per cent.
Climate experts at Environment Can-
ada say it will double in the next 20-
50 years without worldwide efforts to
reduce emissions by 70 per cent or more.
Bloom and his colleagues grew
wheat seedlings with either nitrate or
ammonium under varying concen-
trations of CO2. They discovered that
elevated levels of CO2 inhibited the
processing of nitrate in the wheat
leaves in two ways:
1. Plants place a higher priority on
storing and processing CO2 than they
do nitrogen, so when CO2 levels rose,
some of the chemicals needed to
assimilate the nitrate were already tied
up in assimilating CO2.
2. To use nitrate, plants must convert
nitrate into nitrite and then move the
nitrite into structures within their cells
called chloroplasts, which are the
powerhouses of photosynthesis.
Bloom's research showed that
elevated levels of CO2 interfered with
photosynthesis by blocking this vital
transfer of nitrite into the chloroplasts.
Wheat trowth wasn't influenced
by the type of nitrogen available as
long as CO2 was at a normal level but
when levels were doubled, the leaves
of plants receiving ammonium
increased in size nearly 49 per cent
while plants receiving nitrate
increased only 24 per cent.
The protein content in wheat that
received ammonium increased 73 per
cent under elevated CO2 compared to
32 per cent in that receiving nitrate.
This suggests rising CO2 levels might
diminish the nutritional quality of
grain receiving nitrate fertilizer.0
— Source: Western Producer
`Sniffer' finds E. coli 0157:H7 in manure gas
Michigan State University researchers have developed a new pathogen
identification tool dubbed "The E. coli Sniffer" that sniffs out gases in manure
and identifies those emitted by E. coli 0157:H7, the deadly form of E. coli
responsible for the deaths of seven people in Walkerton two years ago this
month.
What's unique about the new gadget is that its scan results are almost
immediate, compared with the 10 -14 -day wait for a laboratory to conduct
conventional testing,
The significance of the.E. coli Sniffer is substantial. Because the device can
provide early detection of E. coli 0157:H7, livestock producers can detect the
pathogen and then modify their animals' diets to eliminate conditions in their •
intestinal tracts that promote the bacteria's growth. According to one of its
developers, this device can be used on farms, in processing plants and at home,
as well as detecting potential bio -terrorism.
The device was built using seven sensors to detect bacterial gases and
translate them into a digitalized scan on a computer. Unlike other E. coli
sinatures, the 0157:1-17 strain shows "bumps" on the wavy lines, which makes it
easier to identify.
Plans are in the works to commercialize this new device.0
Source: The Meating Place and Pork News
54 THE RURAL VOICE
Research questions
value of preconditioning
calves
New research in Alberta has
found that calves that were wean-
ed and vaccinated at least two
weeks before being transported
long distances had higher shrink
and lower average daily gain than
calves that were never handled.
Karen Schwartzkopf-Genswein,
a beef animal welfare and
behaviour specialist at Alberta
Agriculture's research centre in
Lethbridge, Alberta, said
preconditioned animals that were
hauled 15 hours in a truck had 23
per cent shrink compared to 7.7
per cent shrink in non -precon-
ditioned calves hauled the same
distance.
"We were very surprised by our
findings." he said.
Prior to the study, farmers and
researchers believed precondition-
ed animals would have less shrink
and would recover their body
conditioning faster than animals
that weren't preconditioned.
"The combination of a two-
week precondition and long haul
turned out not to be good for the
animals," she said.
Preconditioned short -haul
calves, however, did not lose as
much daily gain during the 30
days after moving as those hauled
long distances. While calves
shipped 15 hours gained only on
kilogram a day, those hauled for
three hours averaged 1.3 kg a day,
the same as non -preconditioned
calves that had travelled 15 hours.
The best gains came from non -
preconditioned calves which
travelled a short distance, 1.4 kg
per day.
An infrared thermography
camera that takes the surface
temperature of the area around the
eye found preconditioned calves
had a significantly higher
temperature, which researchers
believe shows the calves were
already stressed from weaning and
vaccination.0
— Source: Western Producer
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