Concentration and chemical constituents of lignin are factors that may influence cell‐wall (CW) digestibility of forages. This study was conducted to determine the apparent effect of lignin concentration on extent of CW digestion in immature and mature stems of grasses and legumes and to estimate and relate monomeric products of saponification and nitrobenzene oxidation of lignin to CW digestion. The basal 150 mm of stem from cultivars of field‐grown alfalfa (Medicago sativa L.), birdsfoot trefoil (Lotus corniculatus L.), smooth bromegrass (Bromus inermis Leyss.), orchardgrass (Dactylis glomerata L.), and red clover (Trifolium pratense L.) were harvested during spring growth. Laboratory evaluations included CW digestibility after 72 h of fermentation, neutral‐detergent fiber (to estimate CW concentration), permanganate lignin, alkali‐labile phenolic acids in CW, and nitrobenzene oxidation products (NBO). The apparent inhibition of CW digestion by lignin was 62% greater in grasses than in legumes. In grass stems, ferulic acid was positively correlated with arabinose [r = 0.58 (arabinose determined for another study)], whereas p‐coumaric acid was positively associated with lignin (r = 0.52). The syringaldehyde proportion in NBO increased 61% in grasses and 31% in legumes with stem maturity. The NBO as a proportion of lignin was closely related to CW digestion (r = −0.86) when both grasses and legumes were correlated. The syringaldehyde proportion in NBO was closely related to CW digestion in grass stems (r = −0.93), but not in the legumes (r = −0.23). Thus, there was close agreement between lignin concentration and CW digestibility within grass and legume stems, and the results indicate lignin chemical constituents can be important in accounting for differences in inhibition to digestion between grass and legume lignins.

The regenerative capacity of Schwann cells in the PNS underlies functional repair after injury. In this study, Mindos et al. show a new function for the tumor suppressor Merlin and Hippo/YAP signaling in the generation of repair-competent Schwann cells after injury.

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The most accurate method for determining canopy biomass of pastures for forage availability is by cutting and weighing forage from known areas. Faster methods that require less time and labor would help producers to monitor forage availability in pastures on a daily or weekly basis. Indirect methods rely on calibrations performed on pure or evenly distributed plant compositions to determine forage biomass. However, microclimates developed by varying landscape positions and soil morphological characteristics of pastures may cause uneven plant and species distributions. This study was performed to compare the ability of a modified Robel pole, rising plate meter, canopy height stick, and Li‐Cor LAI 2000 leaf canopy analyzer to determine forage availability in pastures with varying species composition from four areas. Swards consisted of pure warm‐season grass stands, cool‐season grass stands, legume stands, and grass‐legume mixtures. Instrument readings were compared with forage availability determined by clipping and were measured for accuracy, or closeness to clipped weight. For all observations, coefficients of determination (r2), were 0.63, 0.59, 0.55, and 0.32 for the modified Robel pole, rising plate meter, canopy height stick, and leaf canopy analyzer, respectively. For modified Robel pole readings, r2 was highest for observations in red clover (Trifolium pratense L.) (r2 = 0.83), smooth bromegrass (Bromus inermis Leyss.) (r2 = 0.82), and alfalfa (Medicago sativa L. (r2 = 0.76) swards, whereas the rising plate meter r2 values were highest for observations in tall fescue (Festuca arundinacea Schreb.) (r2 = 0.85), alfalfa (r2 = 0.84), and red clover (r2 = 0.73) swards. Grass observations also had their highest r2 values with the modified Robel pole and rising plate meter at 0.63 and 0.59, respectively. The modified Robel pole proved to be the most accurate method used over a variety of species.

Ammonia emission is a major concern for the poultry industry and can be lowered by dietary inclusion of fibrous ingredients and by lowering the dietary CP content. The objectives of this research were to determine the effects of dietary fiber and reduced-CP diets, which may lower NH(3) emission, on egg production and N balance in laying hens. A total of 256 Hy-Line W-36 hens were fed diets with 2 contents of CP (normal and reduced) and 4 fiber treatments in a 2 x 4 factorial arrangement from 23 to 58 wk of age. The fiber treatments included a corn and soybean meal-based control diet and diets formulated with either 10.0% corn dried distillers grains with solubles (DDGS), 7.3% wheat middlings (WM), or 4.8% soybean hulls (SH) added to contribute equal amounts of neutral detergent fiber. The CP contents of the reduced-CP diets were approximately 1 percentage unit lower than that of the normal-CP diets. All diets were formulated on a digestible amino acid basis to be isoenergetic. There were no effects (P > 0.05) of including corn DDGS, WM, or SH in the diet on egg production, egg weight, egg mass, yolk color, feed consumption, feed utilization, or BW gain. Although the corn DDGS and WM diets resulted in an increase (P < 0.001) in N consumption, N excretion was not affected (P > 0.10) compared with hens fed the control diet. The reduced-CP diets did not affect egg weight, feed consumption, or BW gain (P > 0.05); however, egg production, egg mass, feed utilization, N consumption, and N excretion were lower than that from the hens fed the normal-CP diets (P < 0.05). The results of this study show that the diets containing 10% corn DDGS, 7% WM, or 5% SH did not affect egg production or N excretion. However, the 1% lower CP diets caused a lower egg production and lower N excretion.