Annual Review of Ruminant Nutrition in 2007～2008 VI.Forage Utilization

Forage is the main source of nutrition for ruminant.With the continually progress of ruminant nutrition research,the development,utilization and research on roughage resources also has been promoted.The study about forage focused on the following aspects in recent years.①New fodder resources continuing developed.New forage resources,agricultural by-products have been developed on the original roughage basis,and their rational use and suitable adding level also have been studied.②The quality assessment of roughage gradually refined.Forage quality evaluation indices has been developed from relative feed value(RFV),relative forage quality(RFQ)to forage grading index(GI).The new evaluation method will be more accurate on quality assessment of roughage.③Utilization of roughage continuously raised.Enzyme preparation,ionophore,as well as to add fast digestible carbohydrates or fat can effectively improve the digestibility of the fiber,and their reasonable amount has been gradually studied.④Roughage resources have been matching and optimizing.The reasonable matching and optimizing of variety of roughage resources can increasing the breeding efficiency on the basis of guarantee the production performance.⑤Rational use of roughage during the special nutrition period of ruminant gradually studied.Effective use of fodder or grazing during the special stage of beef cattle or dairy cows such as perinatal can make them not only remaining high dry matter intake,but also exhibit good milk production performance and growth performance in the subsequent phase.⑥Roughage storage technology continually enhanced and improved.Hay and silage are the most common and effective way to preserve forage.The influence of different harvesting stage,different conditions for storage,as well as the use of additives on the forage quality has been investigated.Roughage as the main body of ruminant nutrition,reasonable and effective use of the abundant source of roughage resources has important significance for scientific feeding ruminant.