Abstract: Whole cottonseed (WCS) is recognized as a high-protein,high-energy and physically effective fiber feed ingredient and is also processed into cottonseed cake or cottonseed meal (CSM) for use in production.The protein and energy of WCS increases the nutrient content of the diet and improves the digestibility of hay.Addition of moderate amounts of WCS can improve rumen fermentation,dietary digestibility,growth and developmental performance,and milk and meat quality in ruminants.In order to rationalize the use of WCS and develop new protein feeds in actual production,it is necessary to clarify that the appropriate additive amount of WCS is a practical problem that needs to be solved urgently in ruminant farming.At the same time,it is necessary to focus on how to maintain the normal function of the rumen,reduce the feeding cost of the farming industry,improve the feed utilization and economic benefits,and promote the healthy development of the animal husbandry industry.Therefore,the applications of WCS in ruminant production at home and abroad in recent years are summarized,and the effects of WCS on growth and development,slaughter performance,meat quality,lactation performance,milk quality,nutrient metabolism,and rumen fermentation of ruminants are described in relation to the additive amount of different forms of WCS,so as to provide a reference for the improvement of ruminant breeding efficiency.

Key words: whole cottonseed; production performance; rumen fermentation; nutrient metabolism