Dried Rumen Digesta Pellet Can Enhance Nitrogen Utilization in Thai Native, Wagyu-Crossbred Cattle Fed Rice Straw Based Diets

SIMPLE SUMMARY: Generated rumen digesta is wasted and becomes an environmental contaminant in most slaughterhouses in Thailand. Dried rumen digesta (DRD) is a mixture of digestible and indigestible feed residues and are fairly rich in nutrients. DRD has the capacity to become an alternative protein source for ruminants’ diets. DRD in pellet form could be an alternative strategic supplement for Thai-native, Wagyu-crossbred cattle to enhance N balances and microorganisms. ABSTRACT: The goal of the current research was to study the effects of a diet of dried rumen digesta pellets (DRDP) on diet utilization, ruminal microorganisms, and ruminal microbes in Thai native, Wagyu-crossbred cattle. Four Thai native, Wagyu-crossbred, beef cattle were assigned to a 4 × 4 Latin square design to supplement DRDP levels at 0, 50, 100, and 150 g/d, respectively. Rice straw intake, total intake, and estimated energy intake varied significantly among the different DRDP levels. Nitrogen intake, apparent N absorption, and apparent N retention were significantly enhanced when compared to the 0 g/d DRDP. DRDP supplementation at 150 g/d produced the greatest apparent digestibility of crude protein compared to the group that was not fed DRDP. Supplementation of DRDP did not alter the population of protozoa, whereas the addition of 150 g DRDP significantly increased the fungal zoospore. Supplementation of DRDP at various levels did not change the concentration of volatile fatty acid (VFA) or the VFA profiles. Thus, DRDP could be an alternative strategic supplement for Thai-native, Wagyu-crossbred cattle in order to enhance N utilization and fungal zoospores.