Post by barnydhppy on Aug 26, 2010 12:46:23 GMT -5
The following link/posted article has been provided through the conversational thread :Gertie is not feeling well!!
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Trace Element Deficiencies in Ruminants
Trace Element Deficiencies in Ruminants
Clive C. Gay, DVM
Field Disease Investigation Unit
Washington State University
Copper deficiency and selenium
deficiency are the two major problems in
Washington State. We have found no
evidence of cobalt or zinc deficiencies in
this region in our field studies.
SELENIUM DEFICIENCY
A number of diseases or
production inefficiency syndromes are
associated with selenium and/or vitamin
E deficiency. In most of these
syndromes selenium and vitamin E
appear to be complementary but in
terms of recognized deficiencies and
response to treatment selenium is the
most important.
SOIL ASSOCIATIONS
The selenium content of most
soils ranges from 0.1 to 2 parts per
million. But in general soil selenium
content by itself is not a good measure
for the potential for occurrence of
selenium deficiency in livestock grazing
or consuming forages produced from it.
Soil pH has a marked effect on the form
of selenium present and its availability to
the plant. In alkaline, well-aerated soils
with low rainfall selenium forms
selenates and organic selenium
compounds with good availability to
plants. In acid soils ferric iron-selenite
complexes are formed with are poorly
available to plants. On such soils plants
may have adequate or deficient levels of
selenium. In soils with very low
selenium levels the plants produced are
likely to be selenium deficient and the
more acid soil the more likely the
deficiency. Selenium deficiency occurs
in almost all areas of the Pacific
Northwest.
Water, in general, is not a
significant source of selenium as
selenites are precipitated out with
oxides of metals such as iron.
PLANT ASSOCIATIONS
In general grasses contain more
selenium than do clovers or alfalfa but
on low selenium soils the differences
may not be consistent or substantial.
Seasonal conditions influence the
amount of selenium in plants and when
climate favors a lush forage growth
deficiencies can occur. Consequently
pasture levels tend to be lowest in the (cont....)
*******************************************************************************************************
Trace Element Deficiencies in Ruminants
Trace Element Deficiencies in Ruminants
Clive C. Gay, DVM
Field Disease Investigation Unit
Washington State University
Copper deficiency and selenium
deficiency are the two major problems in
Washington State. We have found no
evidence of cobalt or zinc deficiencies in
this region in our field studies.
SELENIUM DEFICIENCY
A number of diseases or
production inefficiency syndromes are
associated with selenium and/or vitamin
E deficiency. In most of these
syndromes selenium and vitamin E
appear to be complementary but in
terms of recognized deficiencies and
response to treatment selenium is the
most important.
SOIL ASSOCIATIONS
The selenium content of most
soils ranges from 0.1 to 2 parts per
million. But in general soil selenium
content by itself is not a good measure
for the potential for occurrence of
selenium deficiency in livestock grazing
or consuming forages produced from it.
Soil pH has a marked effect on the form
of selenium present and its availability to
the plant. In alkaline, well-aerated soils
with low rainfall selenium forms
selenates and organic selenium
compounds with good availability to
plants. In acid soils ferric iron-selenite
complexes are formed with are poorly
available to plants. On such soils plants
may have adequate or deficient levels of
selenium. In soils with very low
selenium levels the plants produced are
likely to be selenium deficient and the
more acid soil the more likely the
deficiency. Selenium deficiency occurs
in almost all areas of the Pacific
Northwest.
Water, in general, is not a
significant source of selenium as
selenites are precipitated out with
oxides of metals such as iron.
PLANT ASSOCIATIONS
In general grasses contain more
selenium than do clovers or alfalfa but
on low selenium soils the differences
may not be consistent or substantial.
Seasonal conditions influence the
amount of selenium in plants and when
climate favors a lush forage growth
deficiencies can occur. Consequently
pasture levels tend to be lowest in the (cont....)