Ensiled Samples Research Articles

Effects of developmental stage and store time on the microbial community and fermentation quality of sweet sorghum silage

This study investigated the effects of developmental stage and store time on the chemical composition, microbial community, co-occurrence networks and fermentation characteristics of sweet sorghum silage. Sweet sorghum harvested at two developmental stages (heading stage, S1; hard dough stage, S2) was treated as follows: (I) natural fermentation of S1 (NS1); (II) natural fermentation of S2 (NS2) and ensiled for 1, 3, 7, 15, 30 and 60 days. After 60 days of ensiling, NS2 silage had higher lactic acid concentration and the ratio of lactic to acetic acid, and lower pH value and acetic acid concentration than NS1 silage. Meanwhile, NS2 silage also had higher ammonia nitrogen (NH3-N) content than NS1 silage, but the NH3-N content of both treatments was lower than 100 g/kg TN. Leuconostoc and Lactococcus were respectively dominant in both 7-day NS1 and NS2 silages, while Lactobacillus was the most abundant genus in 30-day NS1 and NS2 silages. The developmental stage altered the bacterial co-occurrence networks of fresh and ensiled sweet sorghum. Spearman’s correlation heatmap showed that the higher lactic acid content and ratio of lactic to acetic acid in NS2 silage could be associated with the higher water-soluble carbohydrate content in S2 material, the higher abundance of Lactococcus in the initial phase of ensiling and the higher abundance of Lactobacillus in the late phase of ensiling. These results concluded that the sweet sorghum harvested at the hard dough stage is preferred for silage production over the sweet sorghum harvested at the heading stage. HIGHLIGHTS Microbial succession pattern was studied on fresh and ensiled samples. Growth stage affected the chemical and microbial parameters of sweet sorghum. Epiphytic microbiota was correlated with the chemical composition of forage. Metagenomic sequencing showed Lactobacillus was dominated in all silages. Growth stage accelerated the fermentation of sweet sorghum silage.

167 Livestock Literacy: Ensiling newspaper as a renewable fiber source for ruminant animals

Abstract Per unit energy, fiber is among the most expensive components of the ruminant diet. While the use of by- or co-products can help offset the costs of feeding cattle, these feeds often increase in price with increased adoption. Wastes from human enterprises may represent the next step in feedstuff investigation. Our objective was to evaluate the suitability of newspaper as a component of silage for ruminant feeding. Newspapers were obtained from the Dick Smith Library and JTAC News at Tarleton State University (Stephenville, TX). Samples were cut into strips (approximately 4.0 × 30.2 mm) using an office shredder. Sorghum-sudangrass [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud.) de Wet & Harlan] was harvested and cut by hand to lengths of approximately 10 cm. Samples were combined to achieved DM ratios of 100:0, 75:25, 50:50, 25:75, and 0:100% newspaper and sorghum-sudangrass. Distilled water was added to achieve 45% DM. Samples were packed in a double layer of plastic sheeting and sealed in 19 L buckets. Laboratory silos were arranged in a Latin square design in a laboratory and allowed to ferment for 35 d. Ensiled samples were assayed for DM, particle size, and silage acids. There was no effect of newspaper percentage (P = 0.47) on silage pH. Ammonia (0.04 to 1.2% DM), total VFA (0.01 to 4.8% DM), lactic acid (0 to 46.6% VFA), and acetic acid (0.01 to 2.4% DM) increased linearly (P < 0.01) with increased concentration of sorghum-sudangrass. Results indicated that newspaper alone was not an effective feedstuff to ensile. However, addition of newspaper to grass silages could represent a viable means to decrease cost and extend resources for ruminant animal producers.

Nutritional comparison between dried and ensiled indigofera, papaya and moringa leaves

The objective of this experiment was to evaluate chemical composition, in vitro fermentation and digestibility of dried and ensiled indigofera, papaya and moringa leaves. The leaves were subjected to artificial drying in an oven at 60oC for 24 h and ensiling treatment for 30 d under room temperature. Dried and ensiled samples were determined for chemical composition, silage fermentation characteristics and in vitro rumen fermentation and digestibility. The experimental design was a factorial design 3 × 2 in which the first factor was different leaves (indigofera, papaya and moringa) and the second factor was conservation treatments (drying and ensiling). Determination of chemical composition was performed in duplicate whereas in vitro evaluation was conducted in three replicates. Results showed that ensiling treatment decreased CP contents of indigofera and moringa but not papaya leaves. Ensiling also decreased NDF and NDICP contents of all experimental leaves in comparison to drying treatment. The pH of all silages was high and they were characterized with high ammonia concentrations. Ensiled indigofera tended to have lower IVDMD and IVOMD as compared to dried indigofera (P<0.1). It can be concluded that ensiling of high protein forages leads to considerable extent of proteolysis.

Nutritional composition and in vitro digestibility of grass and legume winter (cover) crops

In dairy farming systems, growing winter crops for forage is frequently limited to annual grasses grown in monoculture. The objectives of this study were to determine how cropping grasses alone or in mixtures with legumes affects the yield, nutritional composition, and in vitro digestibility of fresh and ensiled winter crops and the yield, nutritional composition, and in vitro digestibility of the subsequent summer crops. Experimental plots were planted with 15 different winter crops at 3 locations in Virginia. At each site, 4 plots of each treatment were planted in a randomized complete block design. The 15 treatments included 5 winter annual grasses [barley (BA), ryegrass (RG), rye (RY), triticale (TR), and wheat (WT)] in monoculture [i.e., no legumes (NO)] or with 1 of 2 winter annual legumes [crimson clover (CC) and hairy vetch (HV)]. After harvesting the winter crops, corn and forage sorghum were planted within the same plots perpendicular to the winter crop plantings. The nutritional composition and the in vitro digestibility of winter and summer crops were determined for fresh and ensiled samples. Growing grasses in mixtures with CC increased forage dry matter (DM) yield (2.84 Mg/ha), but the yield of mixtures with HV (2.47 Mg/ha) was similar to that of grasses grown in monoculture (2.40 Mg/ha). Growing grasses in mixtures with legumes increased the crude protein concentration of the fresh forage from 13.0% to 15.5% for CC and to 17.3% for HV. For neutral detergent fiber (NDF) concentrations, the interaction between grasses and legumes was significant for both fresh and ensiled forages. Growing BA, RY, and TR in mixtures with legumes decreased NDF concentrations, whereas growing RG and WT with legumes did not affect the NDF concentrations of either the fresh or the ensiled forages. Growing grasses in mixtures with legumes decreased the concentration of sugars of fresh forages relative to grasses grown in monoculture. Primarily, this decrease can be attributed to low concentrations of sugars of mixtures with HV (10.5%). Growing grasses in mixtures with legumes reduced the fiber digestibility of both winter crops (75.7% to 72.8% NDF). Growing grasses in mixtures with legumes did not affect estimated DM yield, nutritional composition, or digestibility of the succeeding summer crops. In conclusion, growing grasses in mixtures with legumes as winter forage crops can increase forage estimated DM yields and its nutritional quality in dairy farming sytems.

The effect of ensiling on variety rank of forage maize

SUMMARYThe objective of the present study was to calculate an optimal harvest period for both fresh and ensiled samples of forage maize and to calculate a set of harvest dates (called a harvest window), for which the variety ranking of the fresh forage corresponds with the variety ranking at the optimal harvest period calculated from the ensiled forage. Forage maize is fed almost exclusively as silage, but official variety trials with silage maize determine quality parameters in fresh (i.e. non-preserved) forage. Eight silage maize varieties were monitored at six harvest dates (from 25 to 40% dry matter content) in Merelbeke (Belgium) in 2013–15. At each harvest date, fresh samples were taken and half of the sampled material was ensiled in micro silos for 20 weeks. An optimal harvest period was calculated based on frequently measuring starch concentration and organic matter digestibility for both fresh and ensiled forage. Eventually, harvesting the silage maize at a dry matter content of 32–35% guaranteed an optimal harvest period. Based on the results of eight varieties, reporting variety ranks without going through the ensiling process continues to be a scientifically justified practice in Belgian official variety trials. Varieties with a superior fresh quality keep their leading position after ensiling, but variety differences become smaller after ensiling.

New applications of near‐infrared spectroscopy in crop and soil analysis

New applications of near‐infrared spectroscopy in crop and soil analysis

Corn silage analysis as influenced by sample size collected

Impact of sample size of chopped corn on nutritive quality following ensiling was evaluated. Seven corn hybrids were sampled at four locations in New York State, each with four field replicates. Material from each chopped plot was mixed and approximately 10kg of material was collected. Samples were thoroughly mixed and 50, 100, 150, 200, 400g, and two 600g subsamples were removed for further processing. One 600g sample was immediately dried, while the remaining samples were vacuum-sealed into polyethylene bags for 30 days. Samples were then evaluated for pH, dried, and ground to pass a 1-mm screen. Samples were analyzed for crude protein (CP) and starch, and analyzed in duplicate for neutral detergent fiber (aNDF) and acid detergent fiber (ADF), and digestions for 30h in duplicate were used to determine in vitro true digestibility (IVTD) and neutral detergent fiber digestibility (NDFD). Experimental design was a randomized complete block, with a split–split plot feature, with locations as the main plot and corn hybrids as the subplot, and sample size as the sub-subplot. The pH of ensiled samples indicated that the ensiling process was adequate. Ensiled samples differed (P<0.001) from fresh corn forage for all parameters, with a 90g/kg difference for NDFD. Hybrid×location interactions (P<0.05) for all parameters except NDFD were due to hybrid germplasm sources responding differently to different environments. All parameters displayed small but significant (P<0.01) linear trends due to sample size. Neutral detergent fiber, ADF, CP, and NDFD all increased with decreasing sample size, while IVTD and starch decreased with decreasing sample size. Analysis of coefficients of variation and a power analysis indicated that variability was relatively consistent down to a 100g sample size for all parameters except starch. Only the 50g sample size appeared different from other sample sizes in minimum detectable contrast at a power value of 0.8. The size of a collected corn forage sample can be as low as 100g without greatly increasing sample variability, but the smaller sample sizes influenced the absolute value of parameters. Sample size could be as small as 400g with a negligible change in sample variability, and without a biologically significant change in nutritive value concentrations.

Effects of ensiling treatments on lactic acid production and supplementary methane formation of maize and amaranth – An advanced green biorefining approach

A green biorefinery enables the material and energetic use of biomass via lactic acid and methane production. Different ensiling techniques were applied to maize and amaranth with the aim to increase the amount of lactic acid in the silage. In addition the methane formation potential of the ensiled samples and the remaining solid residues after separating the organic juice were assessed. Treating maize with homofermentative lactic acid bacteria in combination with carbonated lime increased the amount of lactic acid about 91.9%. For amaranth no additional lactic acid production was obtained by treating the raw material. Specific methane yields for the solid residues of amaranth were significantly lower in comparison to the corresponding silages. The most promising treatment resulted in a production of 127.9±4.1gkg−1 DM lactic acid and a specific methane yield for the solid residue of 349.5±6.6lNkg−1 ODM.

Effects of ensiling maize and sample conditioning on in situ rumen degradation of dry matter, starch and fibre

High-production ruminants are commonly fed maize silage, which makes accurate evaluation of its nutritive value a key economic issue. However, evaluations of the rate and extent of ruminal degradation of starch and cell wall fractions from maize silage carry uncertainty due to the lack of a standardized method. Here, we investigated the effects of ensiling and sample conditioning on in situ-measured degradation of maize forage. Eight series of maize samples (two hybrids×two maturity stages×two methods of conservation [non-ensiled or fresh and ensiled]) were nylon-bagged in three conditionings: dried and ground to 1mm (D1), dried and ground to 4mm (D4), frozen and coarse-ground (FG). Disappearance of dry matter (DM), starch and fibre (aNDF) was measured in situ in cow rumen after different incubation times (2, 4, 8, 16, 24, 48 and 96h). Effects of ensiling, sample conditioning, genotype, maturity and their interactions on DM, starch and aNDF degradation were analyzed using the SAS MIXED procedure. Effective dry matter degradability (ED4DM) was significantly higher (P<0.001) in silage than in fresh maize due to a significantly higher rapidly degradable fraction (a) (P<0.001). Effective starch degradability (ED6Starch) followed the same trend due to a higher silage degradation rate (P<0.01). Conversely, effective aNDF degradability (ED2aNDF) was lower in silage (P<0.001) than fresh maize due to the longer lag-time to degradation (P<0.001) and lower hemicellulose ((aNDF−ADF)/aNDF) fraction in silage. Effective DM degradability was higher (P<0.001) for D1 samples than D4 and FG samples, mainly due to the higher rapidly degradable fraction (a) (P<0.001) in D1 than D4 or FG samples. In relation to high degradation rate, starch degradability was significantly higher (P<0.001) in FG than D1 and D4 samples, whereas aNDF degradation was lowest in the FG samples. This study shows that ensiling maize increases starch degradability and decreases aNDF degradability compared to fresh plant. Alongside conservation method, fine-grinding samples (as D1) led to high losses through the pores of the nylon bags, and these losses were correlated with high starch degradability, whereas coarse grinding (as FG) led to low aNDF degradability, probably due to insufficiently reduced particle sizes. In conclusion, using ensiled samples dried and ground to 4mm (D4) emerges as the appropriate method for in situ studies of starch-rich forages used as silages.

Estimating fermentation characteristics and nutritive value of ensiled and dried pomegranate seeds for ruminants using in vitro gas production technique

The purpose of this study was to determine the chemical composition and estimation of fermentation characteristics and nutritive value of ensiled and dried pomegranate seeds using in vitro gas production technique. Samples were collected, mixed, processed (ensiled and dried) and incubated in vitro with rumen liquor taken from three fistulated Iranian native (Taleshi) steers at 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 h. The results showed that ensiling lead to significant increase in gas production of pomegranate seeds at all incubation times. The gas volume at 24 h incubation, were 25.76 and 17.91 ml/200mg DM for ensiled and dried pomegranate seeds, respectively. The gas production rate (c) also was significantly higher for ensiled groups than dried (0.0930 vs. 0.0643 ml/h). The organic matter digestibility (OMD), metabolizable energy (ME), net energy for lactation (NEL) and short chain fatty acids (SCFA) of ensiled pomegranate seeds were significantly higher than that of dried samples (43.15%, 6.37 MJ/kg DM, 4.43 MJ/kg DM, 0.5553 mmol for ensiled samples vs. 34.62%, 5.10 MJ/kg DM, 3.56 MJ/kg DM, 0.3680 mmol for dried samples, respectively). It can be concluded that ensiling increases the nutritive value of pomegranate seeds.

Chemical composition, including secondary metabolites, and rumen fermentability of seeds and pulp of Californian (USA) and Italian grape pomaces

This study determined the chemical composition and metabolizable energy (ME) value for ruminants of seeds and pulps from grape pomaces (GP), which were produced from white and red Vitis vinifera cultivars in Italy and California (USA). Six Italian ( i.e., three white and three red) and five California red cultivars were collected after the crush of grape juice had been completed and were ensiled in micro-silos for 45 d. Fresh and ensiled samples were manually sieved to separate seeds from the pulp plus skin fraction and an overall inventory of 44 samples was obtained from the 24 Italian and 20 California samples ( i.e., seeds and pulp fractions, fresh or ensiled from 6 or 5 cultivars, respectively). Both in seeds and pulp, the red Italian samples had higher organic matter (P<0.01), ether extract (P<0.05), neutral detergent fiber (aNDF, P<0.01), acid detergent fiber (ADF, P<0.01), lignin(sa, P<0.01) and Cu (P=0.02 and P<0.01, respectively) relative to the California red samples. In addition, K (P<0.01), Fe (P<0.01) and Zn (P=0.03 and P<0.01, respectively in seeds and pulps) were higher in red samples from California versus those from Italy. Italian white samples had higher saponins in pulp (SAP, P<0.05) and tended to have higher total extractable phenolics both in seeds and pulps (P=0.07 and P=0.10, respectively) than did Italian reds. Both in seeds and pulps, ensiling increased concentrations of aNDF (P<0.01 and P=0.08, respectively), ADF (P<0.01) and lignin(sa) (P<0.01 and P=0.03, respectively), had no impact on mineral levels and decreased concentrations anthocyanins (P=0.05) and SAP (P=0.01), respectively in seeds and pulp. Samples were fermented in diluted rumen fluid to measure in vitro rumen fermentability in terms of gas production, which was used to predict ME. Gas production from seeds of different origin were similar, with the exception of higher values at 48 h in red California cultivars with respect to those from Italy (19.2 ml versus 18.0 ml, P<0.05). In pulps, Italian reds did not differ from Italian whites, but had lower gas production than the red California samples (9.2 ml versus 12.2 ml, 16.6 ml versus 21.3 ml, 26.3 versus 32.7, P<0.01, at 4, 24 and 48 h respectively). Ensiling reduced gas production in seeds at 24 and 48 h of incubation (P<0.01) and in pulps at 48 h (P=0.09). Seeds from Italian red samples were lower (P<0.01) in ME than Italian whites (6.23 MJ/kg DM versus 6.89 MJ/kg DM, P<0.01) and higher (P<0.01) than the California samples (5.58 MJ/kg DM). There were no differences between ME of the groups of pulps, but ensiling reduced estimated ME content in seeds (5.94 MJ/kg DM versus 6.54 MJ/kg DM, P<0.01), but not in pulps. On the basis of our results, and in agreement with other recent papers and/or textbook data, the potential to use de-seeded GP as a feed in diets of high producing ruminants is limited.

Prediction of in situ degradation characteristics of neutral detergent fibre (aNDF) in temperate grasses and red clover using near-infrared reflectance spectroscopy (NIRS)

Near-infrared reflectance spectroscopy (NIRS) was used to estimate in situ neutral detergent fibre (aNDF) degradation characteristics. Dried or ensiled samples of perennial grasses and red clover ( n = 382) were used to develop calibration equations. In situ residues of aNDF after 144 h of ruminal incubation were assumed to represent the total indigestible aNDF fraction (aINDF). The fractional degradation rate of aNDF (kdNDF) was calculated assuming first order degradation kinetics with an initial lag time. The aNDF content ranged from 266 to 703 g/kg DM. The aINDF values ranged from 14 to 360 g/kg DM, and the kdNDF varied from 0.020 to 0.137/h. Spectral data was transformed to their second order derivates and a standard normal variate and detrending procedure was used. NIRS prediction were made by modified partial least square technique and prediction accuracy was tested after separating the samples into a validation (close to 70 samples) and calibration dataset. Establishment of new NIRS calibrations and successive predictions of new validation samples were repeated four times. Accuracy of NIRS predictions was evaluated by the standard error of prediction, corrected for bias (SEPC), and by the standard coefficient of determination in prediction ( R P 2 ). Dispersion in sample reference values (square root of variance) divided by SEPC (RPD) was also calculated and a value >2.5 was used as indicator of acceptable prediction. For aINDF, SEPC was 17.7 g/kg DM, R p 2 was 0.92 and RPD 3.4. For kdNDF, SEPC was 0.012/h, R p 2 was 0.51, and the RPD value was 1.7. For the initial lag time, SEPC was 1.27 h, R p 2 was 0.02 and RPD was 1.0. From this study it is concluded that the developed calibration equations had an acceptable prediction of aINDF, and can be used for predicting aINDF for use in practical feed evaluation. The NIRS prediction of kdNDF was less accurate because of weaknesses with the reference method. The initial lag time could not be predicted by NIRS.

Forage Quality Differences of Corn Hybrids as Influenced by Ensiling

Our objective was to determine the impact of ensiling on forage quality of 54 corn hybrids (Zea mays L.). Four field replicates of each hybrid were planted at each of two locations in NY in 2003 (Groveland Station and Aurora, NY). There were differences among hybrids in pH (P < 0.01) at both sites. The pH of ensiled samples was positively correlated with silage DM (r = 0.82) and increased 0.016 pH units for each 1.0% increase in DM. Crude protein of ensiled samples was highly correlated (r = 0.95) with CP of fresh samples, but CP was 0.41% greater in the ensiled samples. Sugar of fresh samples averaged 9.9% while that of corresponding ensiled samples averaged 3.6%. Ranking of hybrids for sugar changed from fresh to ensiled, but was not consistent between sites. There were hybrid × ensiling/fresh interactions for NDF and IVTD at one site; this interaction was not significant at either site for fiber digestibility (NDFD). There was a significant correlation between fresh and ensiled sample NDFD (r = 0.74, P < 0.01). These data suggest little difference between fresh or ensiled hybrid rankings for NDFD, which implies that differences among hybrids in NDFD could be selected by using fresh samples. Inconsistencies for hybrid × ensiling/fresh interactions indicated that more research is needed to fully assess the relative benefits of ensiling prior to quality comparisons of corn hybrids.

Relationships Between Weather Conditions, Agronomic Practices, and Fermentation Characteristics with Deoxynivalenol Content in Fresh and Ensiled Maize.

The deoxynivalenol (DON) content of maize silage was determined in samples collected at harvest and after ensiling in 2001 and 2002 from 30 to 40 Pennsylvania dairies. Information on cultural practices, hybrid maturity, planting, and harvest date was collected from each site. Site-specific weather data and a corn development model were used to estimate hybrid development at each site. Correlation analysis was used to assess the relationship between weather data, hybrid development, cultural practices and preharvest DON. Fermentation characteristics (moisture, pH, and so on) of ensiled samples were measured to study their relationship to postharvest DON contamination. No significant difference (P ≤ 0.05) was noted between the numbers of samples containing DON in 2001 and 2002, although concentration was higher in 2002 samples. A positive correlation was observed between DON concentration of harvest samples and daily average temperature, minimum temperature, and growing degree day during tasselling, silking, and milk stages. A negative correlation was observed between daily average precipitation at blister stage and DON concentration in harvest samples. Samples from no-till or minimum-till locations had higher DON concentrations than moldboard or mixed-till locations. Harvest samples had higher DON concentration than ensiled samples, suggesting that some physical, chemical, or microbiological changes, resulting from ensiling, may reduce DON in storage.

Winter annual small grain forage potential. II. Quantification of nutritive characteristics of four small grain species at six growth stages

Four small grain species, barley, oat, rye, and wheat were harvested at six growth stages to investigate their nutritive quality as a possible replacement for corn silage. Crude protein (CP), in vitro dry matter disappearance (IVDMD), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents were measured on fresh and ensiled samples. The IVDMD, an estimate of forage ruminant digestibility, of all species generally decreased from the vegetative (765–854 g kg‐1) through the milk stage (505–662 g kg‐1) and then remained unchanged or increased slightly through hard dough with the exception of oats which often decreased during later stages of growth. The IVDMD of rye was usually lower than the other species from the milk to hard dough stage. The IVDMD of barley was generally higher than the other species at the soft and hard dough stages. The NDF, ADF, and lignin fractions usually increased from the vegetative to milk stages and remained unchanged or increased slightly through the hard dough stage. The ADF and lignin are negatively associated with forage digestibility while NDF values are negatively related to dry matter intake. The ADF of rye was generally higher than the other species at the milk and soft dough stages. Rye and barley contained more lignin than the other species from the heading through hard dough stage. Crude protein content generally decreased from the vegetative through milk stages and then leveled off or decreased slightly through the hard dough stage. Crude protein of oats was lower than other species at the vegetative stage, while rye generally contained more crude protein than the other species at the vegetative and boot stages. These data in combination with forage yield data reported in an associated paper suggest that small grains can offer a nutritious source of animal feed for farmers in the southeastern United States. Rye tended to stand out among the species at the early stages of growth (vegetative to boot) as a highly digestible green chop or grazing crop that is also high in protein. Barley and wheat stand out as excellent high yielding, nutritious silage choices at the soft dough stage.

Composition of vine-branches with leaves of Vitis vinifera L. fresh and ensiled using different additives (previous results)

Owing to the great extension of vineyards cultivated in Spain, the traditional use of leaves and vine-branches by grazing sheep in some areas and the lack of recent data about composition and nutritive value, a series of trials have been carried out in order to determine the feeding value of this material. In this study previous results on composition and in vitro and in vivo digestibilities are presented. The chemical composition of vine-branches with leaves from first pruning harvested at Moral de Calatrava, Ciudad Real (“Valdepeñas” white vine) were as follows: dry matter, 70%; crude protein, 6.7%; ether extract, 6.2%; crude fiber, 28.1%; ash, 6.7%; nitrogen free extractives, 52.3%; neutral detergent fiber, 52.7%; acid detergent fiber, 33.3%; hemicelluloses, 19.8%; permanganate lignin, 14.0%; permanganate cellulose, 19.3%; acid detergent lignin, 10.2%; Ca, 1.15%; and P, 0.33%. No noticeable content of Silica was detected. Tannins (as tannic acid equivalents), 2.7%. In vitro digestibility, 42.7%. A field silo “in situ” with 20 Kg of fresh material and laboratory microsilos of 2 l were made. Of the latter, four had no additives, four contained added formic acid (5 l t −1 fresh material) and four contained added formaldehyde-sulphuric acid (1.8 and 3.5 Kg t −1 fresh material, respectively). The chemical composition for microsilos without additives, with formic acid, with formaldehyde-sulphuric and for the field silo was, respectively: dry matter, 65.8, 62.4, 64.4 and 68.4%; crude protein, 5.8, 6.3, 6.8 and 6.3%; ether extract, 5.6, 5.4, 5.4 and 5.2%; crude fiber, 31.6, 29.4, 32.3 and 28.3%; ash, 6.8, 6.4, 6.9 and 5.9%; nitrogen free extractives, 50.1, 52.4, 48.5 and 54.3%; neutral detergent fiber, 59.9, 55.1, 62.4 and 56.9%; acid detergent fiber, 39.3, 36.6, 42.7 and 35.4%; hemicelluloses, 20.5, 18.5, 19.6 and 21.4%; permanganate lignin, 18.9, 17.2, 20.4 and 15.6%; permanganate cellulose, 20.4, 19.1, 22.5 and 19.1%; acid detergent lignin, 11.4, 10.5, 14.4 and 9.9%; Ca, 0.95, 1.31, 1.15 and 0.74%; P, 0.41, 0.36, 0.31 and 0.54%; tannins (as tannic acid equivalents, 2.4, 2.6, 1.4 and 2.5 and in vitro digestibility, 34.3, 39.2, 33.7 and 39.1. In vivo digestibility for the field silo was 32.9%. There was no butyric acid and lactic, malic and acetic acids were 66, 22.6 and 11.4% of total acids, respectively. Ammonia nitrogen-total nitrogen ratio was very low; less than 3.2%, the pH value (about 4) was high. From these values it appears that chemical composition and in vitro digestibility of vine-branches with leaves are similar both in fresh and ensiled samples with and without additives. All those values and in vivo digestibility are similar and sometimes higher than those reported for other fibrous feeds commonly used by ruminants.

Evaluation of whisky distillery by-products. II. Studies on the in vitro digestibility of malt distiller's grains.

AbstractThe in vitro digestibility technique has been used to determine the organic matter digestibility (OMD) of dried samples of malt distiller's grains (MDG).The method gave highly reproducible results for OMD of fresh and ensiled samples when different batches of rumen liquor from hay‐fed sheep were used. The results were consistently lower than values determined by in vivo digestibility trials.The OMD values were increased by raising the calcium ion Concentration of the digesta and by extraction of lipids from the MDG samples.The addition of calcium had no effect on fat‐extracted samples of MDG.