• ALFALFA: this can be consumed fresh, from a silo, as a hay or dehydrated. The last two processes are the only ones of interest for the animal feed industry. Haymaking is a natural drying which involves greater duration, greater loss of nutritive value (leaves, protein, vitamins) and greater risk of contamination by soil. What is more, moisture (rain or dew) increases the microbial contamination. Dehydration reduces these problems to the minimum, giving rise to a product of greater quality. The high energy costs of the process mean that a part of the alfalfa marketed as dehydrated in Europe has undergone a prior process of pre-tedding, giving rise to a product of intermediate quality. Alfalfas can be marketed in the form of bales, cubes or granules. Granulation makes handling easier but reduces the proportion of effective fibre.
• STRAW: from cereals it is a highly available fibrous by-product although its use in animal feeds is limited due to its low nutritive value. The composition of straw depends on the proportion of leaves/stems, the diameter of the stem and the height of the plant, in such a manner that there are variations linked to the species, the ecotype and the climatology.