Effects of physically effective fiber on rumen and milk parameters in dairy cows: A review

The objective of this paper is to review the effects of physically effective fiber on rumen function, milk yield, and milk composition and the optimum requirement for dairy cows. Dietary fiber is a vital component of feed that regulates the rumen functions and improves milk quality and milk yield in ruminants. The appropriate particle size and quantity of dietary fiber in the diets of dairy cows help to prevent the occurrence of ruminal disorders and promote healthy rumen functioning and productivity. Currently, sub-acute ruminal acidosis is a common problem in a modern dairy production system. The disease is caused by lack of adequate amount of physically effective dietary fiber in animal feed. Long sized dietary fiber particles stimulate chewing and saliva production would help to maintain reticulo-ruminal buffering capacity. The optimum requirement of fiber for dairy cows depends on the physical form of the fiber source, the chemical composition of the total ration, the stage of lactation and level of production.