Wet Sieving to Measure Particle Length

- [Instructor] In this video, you'll learn about wet sieving.

This is a research method used to determine the particle size of samples such as rumen digesta and fecal material that have a high moisture content.

Wet sieving is valuable because it most accurately mimics the conditions of particles leaving the rumen.

Particles in the rumen are completely water-saturated and suspended in fluid when they pass through the omasal canal, and this is the only particle separating method that closely resembles this action.

Now, Dr. Jud Heinrichs will walk you through the wet sieving process.

- [Dr. Heinrich] First, we're weighing out about 30 grams of wet sample.

Then is mixing it in with distilled water to make a solution.

Different screens go on from largest at the top to smallest at the bottom.

The solution goes in the top.

The solution and sample go in the top.

We put this together in an apparatus that has water coming in the top to wash the sample down through, and then water coming in midway to continue washing the sample down through so that it breaks it up and we can see the particle distribution more like the cow's rumen would see it.

Then it has an oscillating one-dimensional shaking pattern when we're running water through, and this goes on for 10 minutes, so it's a vibration in a one-dimensional form, but it does vibrate and move the particles up and down on the screen surface.

Then, the sample has to be washed down and put into a small bag.

And then this bag is put into an oven and dried down and reweighed so that we know the dry matter content on each sieve.