RE: RC: Lack of sun causes low protein hay?

["Kim Pelletier" <kim@redhorsetech.com>]

Hi there,

With your grass hay, the large amount of rain you have been getting in your
area may be leaching out the available nitrogen in the soil.  Since the
plant has less access to nitrogen, it lowers your protein content.  This of
course, would not be drastic to legumes (alfalfa, clovers, vetch, peanut
hays), since they house nitrogen-fixing bacteria on their roots.  Other
things to consider in crude protein analysis includes the harvesting methods
and the plant's quality/stage of growth.

A good hay color usually indicates that curing was done quickly, requiring
consistantly dry, sunny conditions.  Poorly-cured hay can result in
increased oxidation of some vitamins and their precursors (vitamin A and E
come to mind), but oxidation will also occur with any hay as it just sits in
the hay barn month after month, aging away.

If the hay *was* baled a little too moist (to where it can heat to about 115
to 125 degrees F internally in the bale), you may see a degradation in the
quality and digestibility of protein.  Note: This is with alfalfa hay ---
I'm not that certain about the temperature range in grass hays.  Just FYI
:->.

Usually, crude protein content is dependant on:

   1. The age/stage of growth of the plant when cut.

   2.  The quality of plant growth (did the plant have adequate nutritents
and growing conditions?).  Also, was this year's crop particularly stemmy,
or did it have a lot of leaves on it?  For example, in alfalfa, the leaves
can contain twice as much crude protein as the stems on a per-weight basis.
Dairy-quality alfalfa is irrigated and cut at a young, pre-bloom stage,
resulting in a highly digestible, high protein hay essential for milk
production.  Horse-quality alfalfa hay is older, cut at around 1/10th bloom
(10% of the field is in bloom), resulting in a lower-protein crop more
suitable to equines.

   3.  The harvesting/baling process --- Did the windrow have to be turned
often because of poor drying conditions (rain, damp air, etc.), allowing
more leaves to shatter and drop on to the ground?.  With a series of hot,
sunny drying days, if hay was allowed to dry for too long in the field
because the baler, harobed, etc. broke down, it too can reduce the quality
of your hay.  The extra-dry leaves will shatter when baled and fall to the
ground.  Farming is a gamble, and equipment always seems to break down when
you need it the most (arrrgh!).  Once again, I am not sure how badly grass
hays shatter compared to alfalfa... I would think that they are probably
more tolerant of abuse.

There may be other factors I am not thinking of offhand, but this may give
you a start.  Others beyond the hay field include the method of sample
collection from the bales, which bales were sampled, how the samples were
shipped, and the quality/consistancy of the lab analysis (new or sleepy tech
on board at the lab? Sample/glassware contamination? Calibration is off???).
Lots of factors!

Hope it helps a bit :-)

Kim

(and Lee --- who only cares about ---eating--- the hay <g>)