Effect dietary corn starch intake on pancreatic amylase and intestinal maltase and pH in cattle.

摘要: The pH optimum of pancreatic alpha-amylase from grain-fed steers was determined to be 6.9, while that intestinal maltase established at 5.8. Both assays were found linear up 1 hr incubation. V max amylase 1.15 mg maltose monohydrate produced/hr. Activities and not reduced (P greater than .05) during the interval sample collection animal until analysis 4 later when tissues kept on ice. Twenty-four yearling Holstein fed either alfalfa hay a maintenance level metabolizable energy (ME) intake or corn one, two three times ME slaughtered after being 106 days. pancreas removed alone with sections intestine. Specific activity for high 129% diet .05). Intestinal highest in jejunum decreased toward ileum. Increasing dietary starch resulted no response 10, 30, 50, 70, 90% small intestine length. effect dieesta dependent sampling location within There effects digesta first 10% segment distal pylorus. However, all subsequent sections, higher those levels grain. A calculation estimating th amount needed hydrolyze presented is discussed.