Citrus by-products as ruminant feeds: A review

Increased disposal costs in many parts of the world have increased interest in utilization of citrus by-product feedstuffs (BPF) as alternative feeds for ruminants. The main citrus BPF fed to ruminants are fresh citrus pulp, citrus silage, dried citrus pulp, citrus meal and fines, citrus molasses, citrus peel liquor, and citrus activated sludge. Other minor BPF from citrus include cull or excess fruit. This review evaluates citrus BPF in regard to their physical characteristics, nutrient composition, nutrient digestion, and ruminal fermentation, and their impact on animal performance. Citrus BPF can be used as a high energy feed in ruminant rations to support growth and lactation, with fewer negative effects on rumen fermentation than starch rich feeds. However, when very high levels of some citrus BPF are fed, rumen parakeratosis may occur, particularly when the level of dietary forage is low. (c) 2005 Elsevier B.V. All rights reserved.