Ruminant Lick Blocks, Particularly in China: A Review

A lick block (LB) is a solidified mixture of molasses, urea, minerals, filler, coagulant and binder that is supplemented to livestock mainly in relatively extensive rearing systems. It provides nutrients, such as soluble sugars, proteins, minerals and vitamins to balance dietary intake and can improve rumen fermentation and facilitate digestion and absorption of nutrients. These supplements improve livestock production, reproduction and carcass quality. In addition, LB can partially replace concentrate, serve as a delivery vehicle for additives such as enzymes and drugs and mediate the distribution of grazing livestock. This paper classifies and analyzes representative research; discusses the types, ingredients and current status of the utilization of LB; and systematically reviews the processing technology, quality assessment, influencing factors of intake, action mechanism and application. This review can provide a basis for the development, popularization and application of novel LB products.

Plant cell wall chemistry: implications for ruminant utilisation

Ruminants have adapted to cope with bulky, fibrous forage diets by accommodating a large, diverse microbial population in the reticulo-rumen. Ruminants are dependent on forages as their main sources of energy and other nutrients. Forages are comprised of a complex matrix of cellulose, hemicellulose, protein, minerals and phenolic compounds (including lignin and tannins) with various linkages; many of which are poorly defined. The composition and characteristics of polysaccharides vary greatly among forages and plant cell walls. Plant cell walls are linked and packed together in tight configurations to resist degradation, and hence their nutritional value to animals varies considerably, depending on composition, structure and degradability. An understanding of the inter-relationship between the chemical composition and the degradation of plant cell walls by rumen microorganisms is of major economic importance to ruminant production. Increasing the efficiency of fibre degradation in the rumen has been the subject of extensive research for many decades. This review summarises current knowledge of forage chemistry in order to develop strategies to increase efficiency of forage utilisation by ruminants.