Wheat straw improved by half-rate application of anhydrous ammonia

Many tons of crop residues and other low-quality forages are produced in Kansas each year. Use of these forages often is limited by their low nutrient content and poor digestibility. The process of applying anhydrous ammonia to low-quality forages enhances their feeding value by increasing crude protein content and dry matter digestibility. In the summer of 2012, the persistence of drought conditions throughout Kansas reduced forage supplies and resulted in a dramatic increase in forage prices. In an effort to aid livestock producers, the K-State Beef Extension Specialist Team, in conjunction with the Livestock Production Program Focus Team, conducted wheat straw ammoniation demonstrations at 6 locations across Kansas. The objectives of these demonstrations were to: (1) demonstrate the process of using anhydrous ammonia to treat low-quality roughages, and (2) determine if the recommended rate of 3% anhydrous ammonia application (dry weight) could be decreased as a cost-saving measure. The effects of two anhydrous ammonia application rates (1.5 and 3.0% dry matter weight of stack, equivalent to 30 or 60 lb anhydrous ammonia/ton of dry forage) on subsequent forage quality and digestibility were evaluated

Glial Chloride Homeostasis Under Transient Ischemic Stress

High water permeabilities permit rapid adjustments of glial volume upon changes in external and internal osmolarity, and pathologically altered intracellular chloride concentrations ([Cl–]int) and glial cell swelling are often assumed to represent early events in ischemia, infections, or traumatic brain injury. Experimental data for glial [Cl–]int are lacking for most brain regions, under normal as well as under pathological conditions. We measured [Cl–]int in hippocampal and neocortical astrocytes and in hippocampal radial glia-like (RGL) cells in acute murine brain slices using fluorescence lifetime imaging microscopy with the chloride-sensitive dye MQAE at room temperature. We observed substantial heterogeneity in baseline [Cl–]int, ranging from 14.0 ± 2.0 mM in neocortical astrocytes to 28.4 ± 3.0 mM in dentate gyrus astrocytes. Chloride accumulation by the Na+-K+-2Cl– cotransporter (NKCC1) and chloride outward transport (efflux) through K+-Cl– cotransporters (KCC1 and KCC3) or excitatory amino acid transporter (EAAT) anion channels control [Cl–]int to variable extent in distinct brain regions. In hippocampal astrocytes, blocking NKCC1 decreased [Cl–]int, whereas KCC or EAAT anion channel inhibition had little effect. In contrast, neocortical astrocytic or RGL [Cl–]int was very sensitive to block of chloride outward transport, but not to NKCC1 inhibition. Mathematical modeling demonstrated that higher numbers of NKCC1 and KCC transporters can account for lower [Cl–]int in neocortical than in hippocampal astrocytes. Energy depletion mimicking ischemia for up to 10 min did not result in pronounced changes in [Cl–]int in any of the tested glial cell types. However, [Cl–]int changes occurred under ischemic conditions after blocking selected anion transporters. We conclude that stimulated chloride accumulation and chloride efflux compensate for each other and prevent glial swelling under transient energy deprivation