title: Effects of mineral salt supplement on enteric methane emissions, ruminal fermentation and methanogen community of lactating cows.
abstract: We evaluated the effects of mineral salt supplement on enteric methane emissions, ruminal fermentation and methanogen community of dairy cows over a whole lactation period. Ten Holstein cows fed a total mixed ration (TMR) diet were randomly allocated into two groups, one supplied with mineral salts as the treatment group and the other as the control group. The methane measurement showed that the ingestion of mineral salts lowered enteric methane emissions significantly (P < 0.05), with an average of 10.5% reduction over the whole lactation period. Ruminal fermentation analysis showed the mineral salt intake could significantly decrease the acetate : propionate ratio (P < 0.05). Real-time PCR assay showed that rumen methanogen abundance significantly reduced in the treatment group (P < 0.05) but was not significantly influenced by mineral salt intake over the whole lactation period. Intergroup methanogen community composition was influenced slightly by mineral salt intake; however, significantly different intragroup profiles were apparent throughout the whole lactation period, according to denaturing gradient gel electrophoresis analysis. In conclusion, these results suggested that the effective mitigation of enteric methane emissions by mineral salt intake could be attributed to decreased density of methanogenic archaea and that fluctuations in methane emission over the lactation period might be related to Methanobrevibacter diversity.
authors.affiliation: Agro-environmental Protection Institute, Ministry of Agriculture, Tianjin, China.|Rural Energy & Environment Agency, Ministry of Agriculture, Beijing, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Li
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Chong
authors.initials: C
authors.lastname: Liu
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Yongxing
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Agro-environmental Protection Institute, Ministry of Agriculture, Tianjin, China.
authors.forename: Rongguang
authors.initials: R
authors.lastname: Shi
authors.affiliation: Tianjin Agricultural Environmental Protection Management and Monitoring Station, China.
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Hongmin
authors.initials: H
authors.lastname: Dong
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001105:Archaea; D002417:Cattle; D004032:Diet / Q000662:veterinary*; D019587:Dietary Supplements; D005260:Female; D005285:Fermentation / Q000502:physiology*; D017752:Greenhouse Effect / Q000517:prevention & control; D007774:Lactation / Q000502:physiology*; D008697:Methane / Q000032:analysis / Q000378:metabolism*; D041581:Methanobrevibacter; D008903:Minerals / Q000008:administration & dosage*; D060888:Real-Time Polymerase Chain Reaction; D012417:Rumen / Q000378:metabolism* / Q000382:microbiology
chemical_list: D008903:Minerals; D008697:Methane
keywords: dairy cow; methane; methanogen; mineral salt