Acid Silage Research Articles

The effect of formic acid and urea phosphate-calcium propionate on amino acids in wheat silage

The effect of formic acid and urea phosphate-calcium propionate on amino acids in wheat silage

Changes in amino acid compounds of wheat plants during ensiling and aerobic exposure: the influence of propionic acid and urea phosphate-calcium propionate

SummaryChanges in distribution of amino acid nitrogen of chopped wheat plants ensiled at shooting and flowering when wilted, and at the milk and dough stages as fresh material, were determined as affected by addition of 0·8% propionic acid (PrA) or 2·2% urea phosphate-calcium propionate (UP-CaPr). Analyses were carried out after an ensiling period of 90 days and after a further aerobic exposure period (AE) of 7 days.Total amino acid (TAA) contents in the dry matter (D.M.) during the fermentation period and in the AE were stable in untreated material (UM) and treated material. Concentration of essential amino acids decreased during fermentation, this decrease being higher in the UM. The free amino acids were low in the fresh material (18·6% of TAA) but increased in the ensiled material to ca. 71 % of the TAA in the silage. In the AE this level was 63% in UM and 69% in treated material. The ammonia-N contents increased during fermentation in UM and especially in the UP-CaPr treatments, while the opposite occurred in the PrA treatments.The concentrations of and changes in 21 amino acids (AAs) are given. The highest AA concentrations recorded in the fresh material were those of arginine, lysine, glutamic acid, alanine, leucine, proline and glycine. The most marked increments in AAs as a result of fermentation were those of ornithine, γ-amino butyric acid, threonine and methionine. Marked decreases were observed in glutamine, arginine and glutamic acid. PrA increased mainly arginine, asparagine and glutamine, whereas γ-amino butyric acid decreased; UP-CaPr increased arginine, asparagine, lysine and glutamic acid (in silage only) and reduced γ-amino butyric acid and glutamine (in AE only).

Changes in Organic Acids and Digestibility of Coastal Bermudagrass Silage Pretreated with Monensin

The effect of addition of monensin on the quality of ensiled Coastal bermudagrass was determined. Silage acids, in vitro digestibility, and rumen acids were measured on Coastal bermudagrass of good quality which had been treated with 0 to 375ppm monensin and ensiled for 60 days. Acetic and succinic acids increased and lactic acid decreased in the monensin-treated silage. No formic acid was detected. As indicated by increased pH and higher water-soluble carbohydrates, silage fermentation was inhibited by monensin. In vitro digestibility of monensin-treated silage decreased as monensin increased. The ratio of propionic to acetic acid in rumen fluid increased but dropped off at 125ppm and above in the monensin-treated silage. Isobutyric, isovaleric, and valeric acids increased, but butyric and succinic acids slightly decreased for all treatments in rumen fluid containing the treated silage. Caproic acid remained essentially unchanged in both control and treated silage. Addition of 60 to 62ppm of monensin to Coastal bermudagrass prior to ensiling appeared to be slightly below optimum for production of silage acids but yielded the optimum ratio of acetic to propionic acid in rumen fluid

The effect of extended moist wilting and formic acid additive on the conservation as silage of two grasses differing in total nitrogen content

AbstractHerbage from two contiguous areas of an S.24 perennial ryegrass sward treated with differing levels of fertiliser N (LN and HN) was used to make direct cut (D) and wilted (W) formic acid silages designated LND, LNW, HND and HNW. The major nitrogenous constituents of the herbages and silages were studied and the digestibilities of the silages determined in vivo using cross‐bred wethers. A 96 h wilt under poor drying conditions achieved DM of 26.3% (LNW) and 25.2% (HNW). Wilting had the effect of markedly increasing NPN to reach 37.4% TN (LNW) and 40.4% TN (HNW) after 96 h and there were concomitant increases in herbage free amino‐N, amide‐N and ammonia‐N. However, nitrate‐N decreased significantly during the wilting period and it was assumed that aerobic microbes were active on the crop. The ensiled herbages were well preserved, highest pH value being 4.01 (HNW) and, although NPN levels in wilted silage were significantly higher than unwilted, these did not exceed 50% TN. Changes noted in the free amino compounds included the accumulation of amides during wilting and their removal during ensilage, the accumulation of proline during wilting and the removal of arginine and accumulation of ornithine during the ensilage of wilted herbage. Nitrate also decreased markedly during the ensilage of wilted herbage, LNW and HNW herbages losing 58% and 57% of their nitrate‐N respectively. Ammonia‐N levels in LNW and HNW silages were considerably higher than in LND and HND treatments and this was tentatively linked with increased reduction of nitrate and deamination of amide and arginine during the ensilage of wilted herbages.Nitrogen digestibility coefficients were, respectively 0.672 (LND). 0.643 (LNW), 0.677 (HND) and 0.645 (HNW) and organic matter digestibility coefficients 0.698 (LNW), 0.652 (LNW), 0.666 (HND) and 0.634 (HNW). The differences in nitrogen digestibility between wilted and direct cut silages did not attain statistical significance. It was concluded that a substantial reduction in organic matter digestibility coupled with an increase in the relative proportion of low molecular weight nitrogenous compounds present were the principal effects of extended moist wilting in this experiment.

An Improved Gas-liquid Chromatography for the Simultaneous Determination of Volatile Fatty Acids and Lactic Acid in Silage

An Improved Gas-liquid Chromatography for the Simultaneous Determination of Volatile Fatty Acids and Lactic Acid in Silage

Effect of stage of maturity and chop length on the chemical composition and utilization of formic acid‐treated ryegrass and formic acid silage by sheep

AbstractTwo areas of an early‐heading perennial ryegrass cv. Cropper were harvested by either a precision‐chop or a flail harvester at around 50% ear emergence (15 May 1978) and 14d later (29 May). Formic acid (85%) was applied at the rate of 2·2 litres t‐1. Mature crossbred wethers were used in a 2 × 2 factorial design to determine the effect of stage of maturity and method of harvesting (chop length) on the in vivo digestibilities of formic acid‐treated grass in experiment 1 and formic acid silage in experiment 2. Apparent digestibility coefficients were determined at a fixed level of feeding for both grass and silage and at ad libitum access to feed for silage only.There were no significant differences in the concentrations of crude protein (CP), ether extract (EE), acid‐detergent fibre (ADF) or acid‐detergent lignin (ADL) in grass or silages of differing chop lengths but the later cut forages had significantly higher ADF and ADL concentrations and lower CP concentrations than the early‐cut forages. The ADF and ADL concentrations were also higher in the silages than in the corresponding grasses.In general, the fermentation characteristics of precision‐chopped silage were better than for the corresponding flail‐cut silage but date of harvest was a more important determinant of quality and the late, flail‐cut silage had the highest butyrate and ammonia N concentrations and the highest pH (411) of any treatment. There was a significantly higher intake of precision‐chopped as compared with flail‐cut silage with both the early‐and the late‐cut silage but there were no significant differences attributable to stage of maturity (i.e. date of harvest) or significant interaction between chop length and maturity. The slightly increased intake of early harvested, precision‐chopped silage as compared with late precision‐chopped silage was not significant.Dry matter digestibility (DMD) of the grass decreased at a rate of 0004 units d‐1 post 50% ear emergence. The results of experiment 2 indicated a decrease of 0·207 units d‐1 in silage fed at a similar level. The late‐cut silage (DMD 0·292, mean of both harvesting treatments) thus had a significantly lower digestibility than the corresponding grass (mean DMD 0·247). Chop length had a variable influence on the DMD of both grass and silage fed at a fixed level but treatment differences were non‐significant. However, a trend towards higher digestibility of flail‐cut as compared with precision‐chopped silage was apparent and this became statistically significant when the animals were allowed ad libitum access to feed. This may be a response to the generally lower intake of flail‐cut silage.

The potential value of silage in detoxifying aflatoxin B1.

Serial concentrations of aflatoxin B1 ranging from 200 to 1500 p.p.b. in 2% lactic acid solution (which is the aimed concentration of lactic acid in fresh silage) were assayed for detoxification. Thin-layer chromatography analysis, revealed a complete transformation of 1 000 p.p.b. of aflatoxin B1 to a new fluorescing compount corresponding to aflatoxin B2a which is referred to as hydroxydihydro-aflatoxin B1 toxicity test on chickens confirmed Ciegler's findings (4). The results confirm that the chemical changes taken place in the silo can detoxify aflatoxin B1 to aflatoxin B2a.

高速液体クロマトグラフィーによるコーンサイレージ中の有機酸定量法

高速液体クロマトグラフィーによるコーンサイレージ中の有機酸定量法

Ensiling in acid — A method to stabilize astaxanthin in shrimp processing by-products and improve uptake of this pigment by rainbow trout ( Salmo gairdneri)

It has been demonstrated that astaxanthin is stable in an acid silage of shrimp processing waste, but for a slow conversion of its diester to the corresponding monoester. The digestion by rainbow trout of the astaxanthin present in this waste material was improved by ensiling, to about 71% as compared to 45% in the corresponding fresh or dried material. Also the rate of accumulation of the pigment in the fish muscle was markedly higher in fish fed the silage diet than those given fresh or dried shrimp waste.

Effects of infusing the rumen with acetic acid and nitrogenous constituents in maize silage extracts on food intake, ruminal osmolality and blood acid–base balance in sheep

SUMMARYFour experiments were conducted to determine whether the products of fermentation in maize silage could limit food intake by lambs. In all experiments the lambs were fed ad libitum adietoi dried and pelleted lucerne, but were deprived of food for 4 h on the morning of intraruminal infusion. The infusions were made according to latin-square designs and commenced after 1 h of food deprivation. In Expt 1, the infusion of 3·5 I acetic acid solutions to provide 15, 30 and 60 g acetic acid had no effect (P > 0·05) on cumulative food intake compared with water. In Expt 2 infusion of three maize silage extracts differing in their composition of nitrogenous constituents suppressed (P < 0·05) food intake relative to acetic acid alone, but there were no significant (P < 0·05) differences among the extracts. When 2·71 of an extract from a low dry matter (D.M.) maize silage were infused in Expt 3 cumulative food intake was significantly (P > 0·05) decreased compared with acetic acid, but ruminal osmolality was increased to 430 mosmol/kg and ruminal pH declined to less than 5·5. In Expt 4, 1·5 1 of the low D.M. maize silage extract, an amount actually consumed by lambs during 4 h, decreased voluntary intake by 25% compared with the control but the effect was not statistically significant. Estimates of ruminal osmolality and pH ranged between 250 and 360 mosmol/kg and between 68 and 6·2 respectively. Measures of acid-base status were not affected (P < 0·05) by the infusion of acetic acid or maize silage extract. Whether specific soluble constituents of maize silage fermentation could limit food intake by ruminants was not proven.

サイレージ有機酸の実用的新定量法

サイレージ有機酸の実用的新定量法

Effect of different acidified wet feeds on protease activities in the digestive tract and on growth rate of rainbow trout ( Salmo gairdneri Richardson)

Acidified feeds treated with hydrochloric, formic or sulphuric acid were fed to rainbow trout ( Salmo gairdneri Richardson) to test the effects on protease activities, growth and feed utilization. The acidified feeds were prepared by mixing a frozen stored control feed with fish silage made from the same feed acidified with 2.5% ( w/w) of hydrochloric acid, formic acid or sulphuric acid, respectively. To the silages was added 0.5% ( w/w) propionic acid as a fungicide. The experimental feeds contained 0, 40, 60 and 100% of the fish silages to give final concentrations of, respectively, 0, 1.0, 1.5 and 2.5% ( w/w) of each acid tested. Hydrochloric acid had no apparent effect on growth or proteolytic activities in any part of the digestive tract. Formic acid at all levels tested seems to have a depressive effect on both growth and proteolytic activities. Sulphuric acid showed similar effects, with the exception that the protease activity in the stomach was not depressed. Acidified feeds showed lower feed utilizations than the control feed, this being most pronounced for the formic acid silage.

Improved gas-liquid chromatography for simultaneous determination of volatile fatty acids and lactic acid in silage

Improved gas-liquid chromatography for simultaneous determination of volatile fatty acids and lactic acid in silage

Microbial and Chemical Additives in Alfalfa-Timothy Silage

Mature alfalfa-timothy forage to which were added .125, .25, or .5% ammonia, one of two combinations of microbial additives, a microbial carrier, formic acid, or nothing (control) was ensiled in evacuated or nonevacuated double polyethylene bags to simulate good and poor ensiling. Forages were allowed to ferment for 28 days, after which they were sampled and analyzed to characterize differences in fermentation, protein, and carbohydrates. Forages from both evacuated and unevacuated bags appeared properly fermented. Microbial additives had no significant effect on response variables. Thus, it is unlikely that forage ensiled under good conditions will benefit from the microbial additives used in this experiment. Added ammonia increased the crude protein content from 9.2 to 15.1% of the dry matter at the largest addition. Recovery of added ammonia was high, ranging from 86 to 100% except for relatively low recovery (59%) from evacuated bags at the highest (.5% of wet forage) ammonia. Dry matter concentration was less in ammonia-treated silage than in silages treated with microbes or microbial carriers. In contrast to ammonia-treated silages, formic acid treatment increased concentration of dry matter. Formic acid silage also had the lowest concentration of lactic acid, indicating that addition of formic acid limited the extent of fermentation.

Gaseous Ammonia Treatment of Corn Silage for Dairy Cows

In two experiments corn silages were treated at harvest with urea, gaseous ammonia, or an ammonia-mineral solution and fed ad libitum as the primary forage to 72 lactating Holstein cows in midlactation for 9 to 11 wk. Recoveries of added nitrogen were high (85 to 99%) for all treatments except gaseous ammonia (48%) added in a field harvester. An improved method for addition of gaseous ammonia at the blower through an auger box was developed and tested. Water isoluble nitrogen, lactic acid, and pH in silages were highest for ammonia treatments, next for urea, and lowest for controls; they also were related directly to ammonia. Additions of ammonia and urea retarded increases in temperature and appearance of visible mold when silages were exposed to air, with amonia more effective than urea. Persistencies for milk were as high for cows receiving treated silages as for controls and were not depressed when added ammonia furnished over 30% of the total nitrogen of the ration. No consistent differences from treatments were in silage intakes, conversion of feed to milk, or changes in milk composition or body weight. Addition of gaseous ammonia to corn silage was as beneficial as other nonprotein nitrogen treatments, but retention by silage might be low.

The effect of partial neutralization of formic acid silages with sodium bicarbonate on their volimtary intake by cattle and sheep

AbstractIn two 4 × 4 Latin Square experiments, one with dry cows and one with sheep, animals were given ad libitum early‐cut ryegrass silages prepared using formic acid (2.31 t−1) as an additive. The silages were offered either untreated or partially neutralized with either a low (8 g kg−1 fresh weight) or high (16 g kg−1) level of sodium bicarbonate or with sodium bicarbonate solution (50 g kg−1) given as an intraruminal infusion at a rate sufficient to provide bicarbonate at a rate similar to that provided by the high level of dietary addition.In cows the bicarbonate treatments were associated with a depression in the intake of organic matter which at the high level of addition of bicarbonate was statistically significant (P < 0.05). In sheep the bicarbonate treatments were associated with a slight increase in the intake of organic matter but the efFects were non‐significant (P > 0.05). In both species water intake increased directly with the quantity of bicarbonate ingested.In both experiments the bicarbonate treatments increased rumen pH but there were no significant treatment effects on the concentration of ammonia or of total or individual short‐chain fatty acids in the rumen fluid. In sheep, bicarbonate addition or infusion had no effect on the digestibility of organic matter but at the high levels of bicarbonate supplementation there was a tendency for the digestibility of nitrogen to be depressed.In two further experiments each with two dry cows determinations were made of the effects on food intake of (a) the insertion of water‐filled bags into the rumen and (b) the removal of digesta from the rumen. Treatment (a) produced consistent and significant (P < 0.05) depressions in dry matter intake and treatment (b) increased (P < 0.05) dry matter intake in one cow but not in the other.The lack of significant improvement in silage intake through the addition of sodium bicarbonate to the diet indicated that the acidity of the silage was not a major factor limiting appetite. On the other hand, the effects of the insertion of water‐filled bags into the rumen and of the removal of digesta from the rumen on feed intake were consistent with appetite being controlled through a rumen‐fill mechanism.

The effect of feeding on the hippuric acid content of cow’s urine

The urinary hippuric acid contents of dairy cows on a purified, proteinfree feed (0-feed, 0-cows), as well as the effect of benzoic acid and aromatic amino acid supplements, and silage and hay supplements, on the urinary hippuric acid content, were followed in the present study. The hippuric acid contents of the urine of 0-cows were compared with those of a cow on low-protein, urea-rich feed containing hemicellulose (ULP-cow). and of normally-fed cows (NorP-cows). The urinary hippuric acid content of the 0-cows varied between 0.1 and 0.6g/l (n = 8). The proportion of hippuric acid nitrogen of the total urinary nitrogen was 0.2—0.9 %. The presence of hippuric acid in the urine of the 0-cows indicates an endogenic hippuric acid production within the cow. 0-feed is deficient in all exogenic precursors of benzoic acid. Addition of benzoic acid to the feed of 0-cow caused temporary rise in the hippuric acid contents of the urine, of aromatic amino acids the addition of tyrosine, besides benzoic acid, raised the urinary hippuric acid content by a highly significant amount. The urinary hippuric acid content of the ULP-cow was on average 6.7 g/l (n = 42) and the proportion of hippuric acid on the total urinary nitrogen 5.2 %. The urinary hippuric acid contents of the NorP-cows were on average 11.9 g/l (n = 14), and the proportion of hippuric acid nitrogen of the total urinary nitrogen 10.7%. The difference in the urinary hippuric acid contents with 0- and NorP-cows is significant, as is also the difference in the proportions of hippuric acid nitrogen of the total urinary nitrogen with these cows. The difference in the hippuric acid contents of 0- and ULP-cows is also significant (P < 0.01). The same regards ULP- and NorP-cows (P < 0.01).

Gaschromatographische bestimmung der flüchtigen fettsäuren von C 1 bis C 5 einschliesslich der milchsäure als benzylester unter verwendung von phenyldiazomethan als benzylierungsmittel : Bestimmung der säuren in silagen

Gas chromatographic determination of the volatile fatty acids (C 1- C 5 ) including lactic acid after conversion into their benzyl esters by phenyldiazomethane. Determination of the acids in silages. A gas chromatographic method for the determination of the volatile fatty acids (C 1-C 5) including lactic acid is described. The acids are converted into their benzyl esters by means of phenyldiazomethane without previous purification of the reagent by distillation. The benzyl esters are well separated from the solvent as well as from one another. Silicone SE-30 is used as the stationary phase. An application of the method on silage acids is demonstrated.

Evaluation of formic acid as an additive for lucerne silage

Abstract Pairs of lucerne silage stacks were made on six occasions starting spring 1970. One of each pair received formic acid at about 4 1/t. The other was untreated. The effects of formic acid on the resultant silage were assessed in terms of chemical analysis, digestibility, voluntary intake by sheep, and live-weight gain by sheep and cattle fed the silages as sole diets. Formic acid silages contained more organic matter (85.7 v. 82.6%) and digestible organic matter (56.4 v. 48.7%) and less fibre (35.9 v. 40.4%) than untreated silages, but had lower levels of ammonia (9.4 v. 24.2%), pH (4.36 v. 5.22), and total volatile fatty acids (3.1 v. 7.6%). Daily dry matter intake was: formic acid silage 62.6 and untreated silage 45.6 g/LW0.75. Daily live-weight gains on formic and untreated silages respectively were: sheep 18.8 and — 32.4 g; cattle 442 and 60 g.

Sources of interference in the determination of lactic acid in silage.

Sources of interference in the determination of lactic acid in silage.