Influence of supplemental dietary copper in high roughage rations on nutrient digestibility and methane emission in Holstein bulls

• Published in: Livestock science 2021-02, Vol.244, p.104347, Article 104347
• Main Authors: Sánchez-Sánchez, Victor H., Saynes-Santillan, Vinisa, Gere, José I., Cruz-Monterrosa, Rosy G., Jiménez-Ferrer, Guillermo, Astigarraga, Laura, Loza, Cecilia, Padilla, Juliana, Ramírez-Bribiesca, J. Efrén
• Format: Article
• Language: English
• Subjects: Cattle; Copper; Digestion; Methane; Sulfur hexafluoride
• ISSN: 1871-1413; 1878-0490
• DOI: 10.1016/j.livsci.2020.104347

•Supplemental copper in the diet did not change the fermentation variables in rumen and the total digestibility of nutrients.•Supplemental copper at 40 mg/kg DM tended to decrease the formation of enteric methane.•Copper faecal excretion increased with copper sulfate included in the ration. Feed additives, chemical inhibitors, and biological approaches have been studied and used to inhibit production of enteric methane (CH4) in ruminants by modifying methanogenic bacterial communities. However, information on the potential of micromineral supplements in this regard is limited. The objective of this study was to evaluate the effect of 20 mg (control) and 40 mg Cu (from supplemental CuSO4)/kg dietary dry matter (DM) on nutrient digestion, ruminal fermentation characteristics, and enteric CH4 emissions measured with the tracing technique of sulfur hexafluoride. Six Holstein bulls were divided into two groups of three animals and assigned to one of two experimental diets in a crossover design. Percentages of apparent digestibility of DM, neutral detergent fiber, and N did not differ (P>0.05) between treatments. Supplemental Cu decreased (P0.05) between treatments in ruminal fluid pH or, acetate:propionate ratio. Emission of CH4 tended (P