The effects of feeding α-amylase-enhanced corn silage with different dietary starch concentrations to lactating dairy cows on milk production, nutrient digestibility, and blood metabolites

• DOI: 10.3168/jds.2022-23030
• Publication Date: 2023-06-01T10:32:24Z
• Authors: K.C. Krogstad; B.J. Bradford
• Keywords: Silage; Neutral Detergent Fiber; Latin square

Corn silage is one of the most common ingredients fed to dairy cattle. Advancement corn genetics has improved nutrient digestibility and cow lactation performance in past. A hybrid with enhanced endogenous α-amylase activity (Enogen, Syngenta Seeds LLC) may improve milk production efficiency when lactating cows. Furthermore, evaluating how Enogen interacts different dietary starch content important because ruminal environment influenced by amount rumen fermentable organic matter consumed. To evaluate effects content, we conducted an 8-wk randomized complete block experiment (2-wk covariate period, 6-wk experimental period) a 2 × factorial treatment arrangement using 44 cows (n = 11/treatment; 28 multiparous, 16 primiparous; 151 ± 42 d milk; 668 63.6 kg body weight). Treatment factors were (ENO) or control (CON) included at 40% diet dry 25% (LO) 30% (HI) starch. used CON was similar as ENO but without activity. The period began 41 after harvest. Feed intake yield data collected daily, plasma metabolites fecal pH measured weekly, during first final weeks period. Data analyzed linear mixed model approach repeated measures for all variables except condition score change weight change. silage, starch, week, their interactions fixed effects; baseline covariates also tested. Block served random effects. Plasma glucose, insulin, haptoglobin, serum amyloid concentrations unaffected treatment. Fecal greater versus CON. Dry matter, crude protein, neutral detergent fiber, than wk 1, differences less 6. HI treatments depressed fiber compared LO. (DMI) not affected interaction week; DMI 6, had 1.8 0.93 kg/d LO Milk, energy-corrected milk, protein yields 1.7 0.94 kg/d, 1.3 0.70 65 27 g/d LO, respectively. In conclusion, increased it did affect yield, component yields, DMI. Increasing feed affecting markers inflammation metabolism.