Use of Saponins as Feed Additive in Animal Nutrition

The prohibition of the use of feed additives, including antibiotics and hormones incorporated into animal feed as performance enhancers, has increased the interest in phytochemical substances found in plants. In order to make use of these phytochemical substances, either the plants themselves or their extracts are used. In human medicine, plant extracts are used for their anticarcinogenic, anticholesterol and antihypertensive effects, whilst in animal nutrition these substances are used widely for their aromatic, antioxidant, antimicrobial, antiparasitic and immune stimulatory effects. This review assesses in detail previous studies investigating the antioxidant, antimicrobial, antiparasitic, immune stimulatory and anticholesterol effects of saponin resources obtained generally from Yucca schidigera and Quillaja saponaria, and makes a detailed evaluation of the use of these extracts in animal nutrition.