Increasing Dry Matter Content Research Articles

SlMBP3 Knockout/down in Tomato: Normal-Sized Fruit with Increased Dry Matter Content through Non-Liquefied Locular Tissue by Altered Cell Wall Formation

The phenotypic effect of the knockdown/out of AGAMOUS clade MADS-box gene SlMBP3 in tomato was evaluated using a transferred DNA (T-DNA)-tagged mutant of SlMBP3 and SlMBP3-RNA interference lines. SlMBP3 was preferentially expressed in the locular tissue of fruit and the seed coat combined with the endoderm. Consistent with where SlMBP3 is expressed, the SlMBP3-knockout/down lines showed non-liquefied locular tissues and increased number of seed hairs than the wild type (WT). The early cell degradation of the locular tissue was not observed in the fruits of the SlMBP3-knockout/down lines, and the cells were elongated like placental cells resulting in non-liquefied locular tissues. As the result, the fruits of the SlMBP3-knockout/down lines exhibited higher dry matter contents and titratable acidity than those of the WT. During locular tissue cell development under the SlMBP3 knockout/down, the expression of cell-enlargement-related genes (beta-expansin gene SlEXPB1 and endo-beta-1,4-D-glucanase gene Cel8) and pectinase-inhibitor-related genes (pectin esterase inhibitor gene PE inhibitor and polygalacturonase inhibitor gene PG inhibitor) was upregulated and that of pectinase-encoding genes (polygalacturonase gene QRT3-like and pectin lyase gene PL2) was downregulated. In the seed coat of the SlMBP3-knockout/down lines, tomato trichome-formation-related genes such as MYB genes containing R2 and R3 repeats (R2R3-MYB) transcription factor SlMYB75, B-type cyclin SlCycB2 and Homeodomain Leucine Zipper (HD-Zip) IV transcription factor Woolly were downregulated. Our results demonstrate that SlMBP3 is involved in the liquefaction of the locular tissue through the modification of cell development and degradation processes and seed hair formation in tomato fruits, and the SlMBP3 knockout/down results in normal-sized fruit with increased dry matter content.

Effect of Harvesting Corn after Frost in Alberta (Canada) on Whole-Plant Yield, Nutritive Value, and Kernel Properties

This study compares yield, nutritive value, and kernel properties of whole plant corn (WPC) harvested before and after a light frost in short growing season areas. Six corn hybrids grown in two years at three locations within Alberta (Canada) were harvested before or after the first frost. Samples of WPC were analyzed for dry matter (DM) content, neutral detergent fiber (NDF) concentration, starch concentration, and 48-h in vitro DM and NDF digestibility (DMD and NDFD, respectively). Cob samples were analyzed for DM, and kernels were analyzed for DM, hardness, particle size distribution, density, and stage of maturity. Delaying harvest to after frost increased DM content of WPC at all locations but exceeded the recommended range (32–38%) in the two warmest locations. Whatever the year and hybrid, DM yield was either not affected or decreased after frost. Postfrost harvest increased starch concentration and modified kernel characteristics only if these were less than expected before frost. Fiber concentration was not affected by harvesting time. Frost had either no impact or increased DMD or NDFD of WPC. We conclude that delaying harvest until after frost in short growing season areas can be beneficial when whole-plant DM content is low before frost.

Influence of the melt holding time on fat droplet size and the viscoelastic properties of model spreadable processed cheeses with different compositions

Spreadable processed cheese (SPC) samples, with 30 and 40% (w/w) dry matter (DM) and 30, 40 and 50% (w/w) fat in dry matter (FDM), were produced with nine individual melt holding times (between 0 and 10 min) and stored for 30 days. Milk fat droplet size and viscoelastic properties were determined. In general, longer holding times resulted in decreased diameter of the milk fat droplets in all tested SPC samples. Furthermore, the size of the milk fat droplets decreased with increasing DM content and decreasing FDM content. Furthermore, for most of the produced SPCs, with the progress of the storage time, the G∗ values decreased over the first 2 or 3 min (of the applied holding time). In addition, prolonging the holding time and storage period resulted in an increase of the samples G∗ values. Increased DM content and decreased FDM content in SPC samples resulted in increased G∗ values.

Primary sewage sludge filtration using biomass filter aids and subsequent hydrothermal co-liquefaction

Hydrothermal liquefaction (HTL) is a promising technology for biofuel production and treatment of wastewater sludge. The current study investigates a novel utilization of biomass-assisted filtration of primary sludge to obtain high dry matter (DM) content sludge. Drastic improvements in filtration speed are achieved using different types of lignocellulosic biomass filter aids prepared via mechanical pre-treatment. The combined sludge-biomass filter cake is subsequently used as a feedstock for HTL and shows superior bio-crude yields and properties compared to their individual counterparts. The chemical energy recovery to bio-crude is increased to 75% compared to 46% for biomass and 67% for sludge on its own. The increased DM content of filter cakes (∼25%) compared to primary sludge (5%) increases the energy efficiency of HTL of primary sludge by a factor of 4.5. Introducing a biomass filteraid-HTL combination to a wastewater treatment plant would reduce the organic carbon load to treat by 62%. By combining sludge with lignocellulosic biomass the use of alkali catalyst can be avoided entirely which represents a major cost factor in HTL of lignocellulosics.

Effects of an inoculant containing a Lactobacillus buchneri that produces ferulate-esterase on fermentation products, aerobic stability, and fibre digestibility of maize silage harvested at different stages of maturity

The aim of this research was to study the effects of a commercial inoculant containing Lactobacillus casei and Lactobacillus buchneri that produces ferulate esterase enzymes on fermentation products, aerobic stability, microbial status, dry matter (DM) losses, and digestibility of neutral detergent fibre (aNDF-D) of maize silages ensiled at four stages of maturity. The kernel milk line (ML) was used to time the forage harvest, and 1/6 ML, 2/5 ML, 3/4 ML and black layer (BL) were observed, for harvest stages I, II, III and IV, respectively. Chopped whole plant maize was untreated or treated with L. casei LC32909 and L. buchneri LN40177, which were applied to achieve a final application rate of 1×104cfu/g and 1.0×105cfu/g of fresh forage, respectively. The maize was ensiled in laboratory silos for 260 days before opening. The DM content, starch and ether extract concentrations and mould count increased, whereas water activity, nitrate, ash, water soluble carbohydrates (WSC) and crude protein (CP) contents progressively decreased with increasing maturity at harvest. The 24-h and 48-h aNDF-D were similar for harvest stages I, II and III, whereas they were the lowest in harvest stage IV. The effect of inoculation decreased with increasing DM content at ensiling, and the inoculum was ineffective at the last stage of maturity, probably due to the high epiphytic lactic acid bacteria (LAB) count, low water activity and low sugar content that could have negatively influenced the inoculation outcome. The inoculation lowered the lactic acid, yeast and mould counts and increased acetic acid, 1,2-propanediol, pH, DM losses and aerobic stability in the first three harvest stages, whereas no differences were observed between the treated and untreated silages harvested at the last stage of maturity. Regardless of the treatment, the yeast count fell under the detection limit and the aerobic stability of the silage increased to over 200h when the acetic acid content exceeded 25g/kg DM. Furthermore, the DM losses were closely correlated to the acetic acid production and increased to 80g/kg of DM in the treated silages harvested at the earliest stage of maturity. The potential milk production, estimated with MILK2006 model (Shaver et al., 2006, http://www.uwex.edu/ces/dairynutrition/spreadsheets.cfm), showed that the greater aNDF-D of the treated silage, which was observed in harvest stages I and III, did not counterbalance the higher DM losses attributable to the L. buchneri activity during ensiling, in terms of milk per Mg of original ensiled DM.

Partial replacement of starch with acid detergent fibre and/or neutral detergent soluble fibre at two protein levels: Effects on ileal apparent digestibility and caecal environment of growing rabbits

The effects of the composition of peri-weaning diets on apparent ileal digestibility of nutrients and caecal environment were studied in growing rabbits. Eight diets were formulated according to a 2×2×2 factorial design to increase acid detergent fibre (ADF) from 230 to 290gkg−1 dry matter (DM) at the expense of mainly starch, to increase neutral detergent soluble fibre (NDSF) from 145 to 185gkg−1 DM at the expense of mainly starch, and to reduce crude protein (CP) content from 175 to 145gkg−1 DM. A total of 32 litters of eight kits were randomly assigned to the diets at 17 days of age, weaned at 28 days of age and slaughtered at 35 days of age to collect samples of ileal and caecal contents. The substitution of ADF for starch reduced the coefficient of apparent ileal digestibility (CAID) of DM (0.292 vs. 0.229; P<0.01). The substitution of NDSF for starch increased the CAID of NDSF (−0.040 vs. 0.099; P<0.01). An interaction between dietary ADF and NDSF levels was found for the CAID of CP, higher in the low ADF-low NDSF diets than in the rest (+0.074; P<0.05). The reduction of dietary CP content decreased the CAID of CP (0.578 vs. 0.525; P<0.05) and NDSF (0.086 vs. −0.038; P<0.01). Interactions between dietary ADF and NDSF levels were found affecting full caecum weight as well as DM content and pH of caecal digesta. The increase of ADF in the high NDSF diets reduced full caecum weight (−9.1gkg−1 live weight; P<0.01), increased DM content of caecal digesta (+31gkg−1; P<0.001) and reduced caecal pH (−0.10; P<0.05). In the low NDSF diets, higher ADF increased DM content of caecal digesta to a lesser extent (+16gkg−1; P<0.001) and increased caecal pH (+0.08; P<0.05). The increase of NDSF in the high ADF diets increased full caecum weight (+8.5gkg−1 live weight; P<0.01) and reduced caecal pH (−0.14; P<0.001). In the low ADF diets, higher NDSF increased full caecum weight more extensively (+15.5gkg−1 live weight; P<0.001) and reduced DM content of caecal digesta (−16gkg−1; P<0.001). Both ADF and NDSF replacing starch increased total volatile fatty acid (VFA) concentration of caecal digesta (+11.5% and +13.9%, respectively; P<0.01). The replacement with NDSF increased molar proportion of butyrate (0.095 vs. 0.112; P<0.001) at the expense of mainly acetate (0.841 vs. 0.820; P<0.001) and reduced ammonia concentration of caecal digesta (−8.1%; P<0.05). The reduction of dietary CP content decreased total VFA (−14.4%; P<0.001) and ammonia (−23.5%; P<0.001) concentrations of caecal digesta and increased caecal pH (5.87 vs. 5.93; P<0.05). Overall, the three dietary changes under study led to changes in the caecal environment which might be effective in reducing mortality rate in a context of rabbit epizootic enteropathy.

Características fermentativas de silagens de polpa de café com diferentes proporções de casca de café

Este trabalho teve como objetivo avaliar a composição química e as características fermentativas de silagens da polpa de café com diferentes proporções de casca de café. O material foi ensilado em PVC de 150 mm de diâmetro por 750 mm de altura, segundo os tratamentos: polpa de café (PC), PC + 20% de casca de café (CC), PC + 40% de CC e PC + 60% de CC, segundo delineamento inteiramente casualizado com seis repetições. Os silos foram abertos 60 dias após o fechamento, quando foram retiradas amostras para determinação dos teores de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), lignina, celulose, pH, N-NH3, cafeína, cálcio (Ca), fósforo (P) e digestibilidade in vitro da MS (DIVMS). Determinou-se também a produção de efluentes e de gás. Houve um aumento linear no teor de MS e pH, à medida que foi adicionado casca de café nas silagens, e decréscimo linear nos teores de PB, FDN e FDA, lignina, celulose, cafeína, Ca e P. Esse decréscimo ocorreu pelo fato da casca de café possuir teores inferiores ao da polpa para PB, FDN, FDA, cafeína, Ca e P. Houve também redução linear nos valores de N-NH3, e somente a silagem com maior porcentagem de casca de café obteve valor inferior a 10%, considerado como limite para silagem de boa qualidade. A produção de efluentes foi maior para a silagem de polpa de café sem casca e não se obteve nenhuma produção na silagem com 60% de casca. Não houve diferença significativa na DIVMS entre os tratamentos. A casca de café foi efetiva em aumentar o teor de MS da silagem de PC e em reduzir os teores de FDN, FDA, N-NH3, proporcionando silagem de valor nutritivo satisfatório à alimentação de bovinos, criando, assim, alternativa para aproveitamento desses resíduos. Ao considerar o teor de MS encontrado nas silagens, a melhor quantidade de casca de café a ser acrescentada à polpa de café, para produção de silagem está entre 30% e 35%.

QTL for Yield, Earliness, and Cell Wall Quality Traits in Topcross Experiments of the F838 × F286 Early Maize RIL Progeny

ABSTRACTQTL for cell wall digestibility related traits were investigated in maize (Zea mays L.) topcross experiments of 240 RILs obtained from the F838 × F286 early maize hybrid. Genotype effects were highly significant for all agronomic and cell wall related traits and much higher than genotype × environment (GE) interaction effects for cell wall digestibility traits. Eight quantitative trait loci (QTL) for dry matter (DM) yield were observed, out of which only one increasing allele originated from F286. Conversely, three QTL out of four with alleles increasing DM content at silage harvest stage originated from the earliest F286 line. Out of four QTL increasing starch content, two QTL, which originated from F838, did not colocalize with silking date QTL or any other investigated traits. Ten QTL were observed for lignin content and between six and nine QTL were observed for each of the three cell wall digestibility investigated traits. QTL located in bins 1.02 (position 76–80 cM), 1.07 (position 228–230 cM), and 8.07 (position 134–142 cM) are likely of priority interest when it comes to improving maize cell wall digestibility. Candidate genes underlying cell wall digestibility QTL were searched for on the basis of in silico investigations and with maize, Arabidopsis, poplar, and eucalyptus genomic information. In most of QTL positions, transcription factors regulating cell wall lignification were shown to be the currently most plausible candidates involved in genetic variation of maize cell wall digestibility.

Stability of fatty acids in grass and maize silages after exposure to air during the feed out period

Lipids in forages are extensively hydrolysed in the silo with a concomitant increase in the level of free fatty acids (FFA). After opening of the silo, exposure of the FFA to air and light with, a concomitant increase in pH and microbial growth, could induce oxidization. The present study investigated the stability of FA in grass and maize silages exposed to air for 0, 12 and 24 h. Eight maize silages were selected with varying dry matter (DM) contents, being very wet, wet, normal and dry. In addition, eight grass silages were chosen on the basis of ammonia (NH 3) concentration and pH level. Grass and maize silages were sampled 8–10 weeks after ensiling and anaerobically transported to the lab in cooled plastic bags. After mixing, each sample was divided into three subsamples and exposed to air for 0, 12 or 24 h. Concentrations of individual FA were quantified by gas chromatography. Among the investigated silages, concentrations of total FA varied greatly and ranged from 16.4 to 23.9 and 9.5 to 21.6 g/kg DM in grass and maize silages, respectively. Exposure to air up to 24 h lowered ( P<0.01) the contents of linolenic acid (C18:3), linoleic acid (C18:2), oleic acid (C18:1) and total FA in maize silages. In grass silages, 24 h exposure to air decreased ( P<0.05) concentrations of C18:3, C18:2 and total FA ( P<0.01). In both grass and maize silages a decline in concentrations of major unsaturated FA (UFA) was associated with a concomitant increase ( P<0.01) in the proportion (g/g total FA) of palmitic acid (C16:0). The relative decrease in total FA after 24 h exposure to air was higher in maize silages with a high moisture content, and progressively decreased with increasing DM content. In contrast, pH and NH 3 levels of grass silages had no effect on the stability of FA during feed out. The present study demonstrates that extended exposure of silages to air during feeding increased the proportion (g/g total FA) of C16:0 and lowered the concentration of polyunsaturated FA.

Influence of ensiling forages at different dry matters and silage additives on lipid metabolism and fatty acid composition

White and red clover silages have been shown to result in a higher transfer efficiency of polyunsaturated fatty acids (PUFA) to the milk or meat of ruminants compared to ryegrass silages. For red clover this has been related to protein bound phenols formed by polyphenol oxidase (PPO). PPO is typically active in red clover and the protein bound phenols, which are the result of PPO activity, could result in a decrease in PUFA biohydrogenation in the rumen through inhibition of lipolysis in the silage and/or in the rumen, as lipolysis is a prerequisite of biohydrogenation. Higher transfers of white clover PUFA have been associated with increased rumen outflow rates, although lower in silo lipolysis also has been observed. No research on effect of ensiling agricultural practice as dry matter (DM) and using different silage additives on extent of in silo lipolysis has been performed earlier. Therefore, the goal of this experiment was to study the effect of formic acid, an inoculum or a carbonate buffer as a silage additive and DM content of the wilted forages at ensiling on fatty acid (FA) composition and lipolysis in silages of red clover, white clover and ryegrass. Furthermore, it was attempted to link lipase activity measured as the p-nitrophenyl butyrate hydrolyzing activity of a protein extract with in silo lipolysis and to study the correlation of this enzyme activity with the amount of protein bound phenols. Higher DM content at ensiling resulted in lower linolenic acid concentrations, which was suggested to be related to the longer wilting period and more extensive oxidation. Formic acid resulted in a lower lipolysis in all forages compared to the other treatments. The effect of DM content was rather limited, although lipolysis decreased slightly with increasing DM content in ryegrass. Lipolysis was lower in silages of red and white clover compared to ryegrass at 300 g DM/kg. At higher DM contents lipolysis was equal or lower in ryegrass silages. Enzyme activity measurements indicated bound phenols could inhibit enzyme activity, both in red and in white clover. However, no direct link between measured plant lipase activity of wilted forages and in silo lipolysis could be found.

Using time domain reflectometry to characterize cattle and pig slurry infiltration into soil

The rate and extent to which cattle or pig slurry infiltrates into soil after application is one of the important factors determining the rate and extent of subsequent ammonia (NH 3 ) volatilization. Better characterization of the infiltration process is required to improve predictive models of NH 3 losses after land spreading. This paper describes a laboratory system using time domain reflectometry to measure slurry infiltration into soil columns. This system enabled semi-continuous, non-destructive infiltration measurements to be made, assessing the influence of slurry type, dry matter (DM) content, soil type and soil water tension. Differences were noted in the infiltration behaviour of cattle and pig slurries. For cattle slurry, DM content (range 1.7-7.1%) was the main influencing factor. Infiltration rate rapidly decreased with increasing DM content and there was no influence of soil type or water tension. For pig slurry, all of the slurry infiltrated into a sandy clay loam soil within the first hour, regardless of DM content (range 1.5-4.7%), whereas only 60% infiltrated into a clay loam soil over the same time period (slurry DM content 2.1%).

Parthenocarpy restores fruitfulness in sterile triploid (3x) tomatoes artificially obtained by crossing 4x x 2x somaclones

SummaryTo breed fruitful triploid tomatoes, diploid (2x) and tetraploid (4x) plants were regenerated from hypocotyl explants, using two pairs of near-isogenic lines differing respectively for the parthenocarpic fruit and parthenocarpic fruit-2 mutations. From 626 regenerated shoots, 53 were tetraploid. In the 4x plants, the mean number of fruits was lower than in the 2x class for all the genotypes, but in the two parthenocarpic lines it was higher than in the respective wild-types at the same ploidy level. Compared with 2x, the mean weight of 4x fruits was lower in wild-type and higher in parthenocarpic lines. Out of four cross combinations between tetraploid and diploid plants (within two parthenocarpic and two corresponding wild-type lines), only two yielded seeds (the parthenocarpic fruit line and its near-isogenic wild-type). Triploids were vegetatively propagated and evaluated in a field trial. Whereas wild-type triploids were completely sterile, the 3x parthenocarpic fruit plants had a fruit set that was not statistically different from that observed in 2x individuals. Mean fruit weight in 3x parthenocarpic plants was also higher than in 2x and comparable with 4x plants. Yield estimates in such triploids were not statistically different from those recorded in diploids, both wild-type and parthenocarpic. Triploid fruits had a soluble solids value higher than 2x fruits. The total seedlessness and the increased dry-matter content appeared traits peculiar to triploid parthenocarpic fruits. Therefore, triploids may deserve interest in breeding fresh market and processing tomatoes, providing that their commercial multiplication is ensured by micropropagation.

The effect of wilting chicory on its voluntary feed intake and digestion by red deer

Two experiments were conducted at Palmerston North, New Zealand during 1997, to investigate the effects of wilting chicory to reduce its bulkiness upon voluntary intake of fresh feed and dry matter (DM), apparent digestibility and voluntary water intake. In Expt 1 fresh chicory was cut and wilted for 48 h to determine the drying rate; wilting for 24 h increased DM content from 87 to 173 g/kg, reduced in vitro organic matter digestibility (OMD) by 0·016 (P&lt;0·05) and was selected for use in Expt 2. In Expt 2, chicory was fed either fresh (113 g/kg DM) or wilted (250 g/kg DM) to castrated male red deer kept indoors over two time periods, late autumn and early spring. Chemical analyses showed that wilting slightly lowered the concentration of water-soluble carbohydrate from 185 to 158 g/kg DM, but did not change any other aspect of composition. There were no significant differences between fresh and wilted chicory in apparent digestibility of DM, organic matter (OM), hemicellulose and cellulose. Wilting significantly lowered voluntary intake of fresh feed (P&lt;0·01), but significantly increased voluntary DM intake from 49 to 57 g DM/kg W0·75/day (P&lt;0·05). Wilting chicory lowered feed water intake (P&lt;0·01) but increased drinking water consumed (P&lt;0·001), with total water intake still being slightly lower (P&lt;0·05) for deer fed wilted chicory.It was concluded that wilting chicory increased DM intake by reducing its bulkiness, without seriously affecting digestibility, and it is suggested that the feasibility of breeding forage chicory for higher leaf DM content should be investigated. A comparison with literature values showed that DM contents of fresh forages &lt; c. 150 g/kg are likely to restrict the voluntary DM intake of ruminants.

The effect of dry matter content and silage additives on the fermentation of grass silage on commercial farms

AbstractA total of 1713 samples of silage from commercial farm silos were analysed to investigate the effect of dry matter (DM) content and chemical additives on fermentation as measured by ammonia‐N concentration and pH, Increasing DM content without additive use had a major beneficial influence upon fermentation. When silage DM contents were greater than 260 g kg‐1 83% of silages were well fermented, with average ammonia‐N concentrations of 94 g (kg total N)‐1 and pH 4.36. With diminishing DM concentration the proportion of well fermented silages declined. In the DM range 220‐260 g kg‐1 67% of silages were well fermented with ammonia‐N concentrations of 125 g (kg total N)‐1 and pH 4.30, in the DM range 180‐220 g kg‐1 48% were well fermented with ammonia‐N at 151 g (kg total N)‐1 and pH 4.38 and with DM below 180 g kg‐1 no silages were well fermented with ammonia‐N concentration of 252 g (kg total N)‐1 and pH 4.84.The benefit of chemical additives, albeit at poorly defined and often inadequate rates, was small in comparison to that of increased DM concentration. Below DM concentrations of 180 and 220 g kg‐1, the only benefit was that formic acid decreased ammonia‐N to 151 g (kg total N)‐1 and pH to 4.32 compared with 163 g (kg total N)‐1 and pH 4.43 for untreated silages. Within the DM range 220‐260 g kg‐1 formic acid decreased ammonia‐N level to 104 g (kg total N)‐1 and pH to 4.07, and there was a slight benefit from using sulphuric acid/formalin which decreased ammonia‐N to 117 g (kg total N)‐1 and pH to 4.23 compared with 125 g (kg total N)‐1 and pH 4.27 for untreated silages. Above 260 g DM kg‐1 both formic acid and sulphuric acid/formalin provided a small but consistent decrease in ammonia‐N and pH compared with untreated silages. Chemical additive use conferred no other benefit when compared with untreated silage. Calcium formate/sodium nitrite mixtures and acid mixture use provided no benefit in fermentation compared with untreated herbage.

COMPARISON OF METHODS FOR DRY MATTER DETERMINATION OF HIGH MOISTURE GRAIN CORN

Comparisons were made between methods of determining the dry matter (DM) content of high moisture (HM) ground ear corn, preserved five months earlier with volatile fatty acids (VFA), and HM shelled corn at harvest. The effect of fine grinding (1 mm diameter screen) of HM shelled corn samples prior to DM determination also was examined. There were no differences in DM content of HM shelled corn between toluene distillation, oven-drying, or semi-automatic moisture testing. With HM ground ear corn, DM values obtained by toluene were greater (P &lt; 0.01) than for the other methods. Fine grinding of the samples resulted in increased DM content (P &lt; 0.01). However, differences between methods were apparently confounded by the presence of VFA. Air-drying HM shelled corn at 65 C for 24 hr, prior to DM determination, resulted in a 3% (P &lt; 0.01) increase in DM content. However, there was a significant interaction (P &lt; 0.01) with the effect of fine grinding; hence, the most accurate DM determinations were obtained when the samples were finely ground after air-drying. The least accurate sample preparation was from finely ground corn which had not previously been air dried. Moisture was apparently lost during grinding due to equilibration with atmospheric moisture.