Usually, feed intake is reduced with reduced particle size. However, there seems to be an optimum particle size of between 500 and 700 microns.
Dr Michael Kisembo, a veterinary doctor, says the efficiency of feed improves as a result of improved nutrient digestibility.
In this case, the average daily weight gain of animals from reducing the size of the feed particles does not suffer. Typically, reducing the particle size reduces feed intake. Nevertheless, the optimum particle size is 500-700 microns.
He says in addition, size distribution is related to feeding behaviour and digestion of the feed particles by animals.
Since the particles have irregular shapes, size measurement is defined as the diameter of the theoretical sphere whose behavior is similar to that of the real particle. The distribution is then fitted to theoretical laws. The fineness of the meal is described by the mean diameter and the heterogeneity of the distribution by the standard deviation.
Among the main techniques commonly used are sieving (in dry or wet conditions), laser light diffraction and imaging. The last two techniques are non-invasive and fast techniques that can be used online.
Most of the feed ingredients used in feed manufacturing are subjected to particle size reduction either within the feed plant or before receiving. The greatest benefits from particle size reduction in feed manufacturing processes are related to:
1. Greater surface area for faster digestion
2. Improving ease of handling of some ingredients
3. Improving mixing characteristics of ingredients
4. Increasing pelleting efficiency and pellet quality
5. Meeting customer performance for feeds.
