Valuation of leaves as alternative fibrous raw materials in goats

Goats are characterized by their great ability to adapt to the environment , even in the most unfavorable ecosystems. This is primarily due to their poor food taste selectivity, although they have a special predilection for wet forages and pastures.

Another adaptive advantage of the goats is their ability to forage, that is given by the standing behavior , which consists in stand on their hind legs and stretch out to browse buds in the branches of trees and shrubs with a height up to 2 meters.

Goats are considered by Hoffmann (1988) as: intermediate consumers in the classification of herbivores that he proposes, although they are able to adapt to other environments and act as concentrate selectors or consumers of low-quality forages.

According to Morand and Sauvant (1984), goats are defined as adaptive consumers with medium to high selectivity, what is partially related to their mouth anatomical characteristics (mobile lips and prehensile tongue). This enables the species to have a greater selectivity.

On the other hand, goats do not reject the bitter taste  of shrub legumes, which is caused by the presence of tannins.

» These particular nutritional characteristics of their feeding behavior have determined the difficulty of providing a diet that is appetizing and contains the necessary nutrients to maintain a good physiological condition and to get acceptable production levels.

Goats often choose different types of plants for consumption. This increases the possibility of adding plants that are rich in alkaloids, terpenes and tannins, for example, to the diet, thanks to their continuous search behavior during grazing. This behavior allows them to balance the diet to counteract the undesirable effects of these compounds.

• They accept all types of foods, but not always in the same way.

• In the case of monotonous food, they reduce consumption and increase waste.

For instance, in the case of tannins it has been identified some adaptation in their ruminal microflora through the presence of tannin-tolerant microorganisms. The existence of this adapted microflora ensures the subsistence of goats in hostile environments.