Fermentation Quality and Nutritive Value of Total Mixed Ration Silage of Green Tea Grounds

Abstract

Six wethers were used in a replicated 3 × 3 Latin square to study the fermentation quality and nutritive value of total mixed ration (TMR) silages which included wet green tea grounds (WGTG). The TMR silages were prepared using compound feed, corn, soybean meal, timothy hay, alfalfa hay, dried beet pulp and vitamin-mineral supplement, with soybean meal and alfalfa hay being replaced by WGTG at 0, 10 or 20% on dar matter (DM) basis. All TMR silages, irrespective of WGTG addition, were well preserved with low pH and ammonia-N content, and high lactic acid content. Increasing concentrations of WGTG in the rations decreased the digestibility of DM, organic matter, crude protein and energy (P < 0.05). The total digestibility nutrients and digestible energy contents of TMR silages at 0% and 10% WGTG were similar, however, the TMR silage at 20% WGTG was lower (P < 0.05). With progressive increases in WGTG concentrations, intake nitrogen, urinary nitrogen and retained nitrogen did not differ, but the fecal nitrogen increased (P < 0.01). This study demonstrated that the proportion of WGTG to be incorporated into TMR silages should not exceed 10% of the DM.