Affiliation:
1. CAS Key Laboratory for Agro‐Ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences Changsha China
2. Department of Animal Science and Technology University of Hunan Agricultural University Changsha China
3. Department of Animal Science and Technology University of Guangxi Nanning China
Abstract
AbstractBACKGROUNDBetter utilization of rape straw can provide alternative strategies for sustainable ruminant and food production. The research reported here investigated changes in the carbohydrate composition of rape straw as a result of mixed ensiling with whole‐crop corn or inoculated with nitrate, and the consequent effects on ruminal fermentation through in vitro batch culture. The three treatments included: rape straw and corn silage (RSTC), and ensiling treatment of rape straw with whole‐crop corn (RSIC) or with calcium nitrate inoculation (RSICN).RESULTSEnsiling treatment of rape straw and whole‐crop corn or plus nitrate enriched lactic acid bacteria and lactate. The treatments broke the fiber surface connections of rape straw, leading to higher neutral detergent soluble (NDS) content and lower fiber content. Ensiling treatments led to greater (P < 0.05) dry matter degradation (DMD), molar proportions of propionate and butyrate, relative abundance of the phylum Bacteroidetes and genus Prevotella, and lower (P < 0.05) methane production in terms of g kg−1 DMD, molar proportions of acetate, and lower acetate to propionate ratio than the RSTC treatment. The RSICN treatment led to the lowest (P < 0.05) hydrogen concentration and methane production among the three treatments.CONCLUSIONEnsiling treatments of rape straw and whole‐crop corn destroy the micro‐structure of rape straw, promote substrate degradation by enriching the phylum Bacteroidetes and the genus Prevotella, and decrease methane production by favoring propionate and butyrate production. Nitrate inoculation in the ensiling treatment of rape straw and whole‐crop corn further decreases methane production without influencing substrate degradation by providing an additional hydrogen sink. © 2023 Society of Chemical Industry.
Funder
National Natural Science Foundation of China
Subject
Nutrition and Dietetics,Agronomy and Crop Science,Food Science,Biotechnology