Tag Archives: ammonia levels

To Till or Not to Till

I had a grower call me yesterday with some questions about ammonia levels in his houses.  This was only his second flock on this bedding but he was having troubles keeping his ammonia levels where he thought they should be.  This reminded me of a study I had finished at the end of the summer.  To go to the beginning, I listened to a speaker talk about litter management a few years ago.  He was discussing litter manipulation and he was very opposed to tilling.  His discussion included the facts and figures his company had collected regarding ammonia and bacteria release due to tilling of litter.  I don’t remember what he said that I disagreed so strongly with but something didn’t set right with me.  Consequently, I wanted to test what difference tilling made.  I brought the Boss in on the discussion.  She is a tilling believer (as long as it is managed correctly) so she readily agreed.  Our integrator is not thrilled with tilling but they are very open minded about improvements to the industry and agreed to work with us on the project.

We have four broiler houses.  We chose to till two of the houses after each flock for one year.  We did this August of 2012 to August of 2013.  We started with fresh bedding.  Each house was placed with a 50/50 mix of rice hulls and kiln dried pine shavings.  After each flock, all four houses were decaked.  Houses 1 and 4 were then tilled four consecutive days.  We did this for five flocks (it was a slow year with a lot of down time between flocks, there should have been six).  After the fifth flock, we cleaned out again.

Once the fifth flock was completed, the performance of each house over the five flocks was analyzed.  I used JMP to analyze the data.  The houses were compared using these variables:


Total Weight Shipped

Feed Intake

Water Intake

The statistical analysis results are located here Till stats if you would like to see them.

What I found was not a whole lot.  There was no statistical difference between the houses in any of these four areas.  It is possible that, if I could collect paw scores or plant condemn information per house, I might be able to find some difference.

I think it is important to keep in mind when looking at stuff like this, that the results were based on the methods.  Change the methods and you might change the results.  For example, many growers who till only do so once per flock.  I did it four times to make sure the litter dried.  Control the moisture and you control the ammonia.  Some growers till instead of decaking.  I chose not to do this because of the moisture in the cake.  By removing the cake instead of tilling it, I think I get more moisture out of the house.  A grower who did not decake

Student employee, Christopher, prepping a house for the next flock.
Student employee, Christopher, prepping a house for the next flock.

and only tilled once may have very different results than ours.

Tilling is a little bit of a controversial issue and many folks have an opinion.  You just read mine.  We don’t till any more just because it apparently make a difference.  At least not in the scenario I outlined.  It may have some uses in moisture and ammonia management in certain situations.

As always, leave me a note or send me any email with thoughts or questions.  Merry Christmas to you all.