Preservation of baled hay with propionic and formic acids and a proprietary additive

Field-baled hay was incompletely preserved using propionic or formic acids. Results were most satisfactory, although moulding by Aspergillus glaucus group was still frequent, when die hay contained less than 30% water and propionic acid was used. However, much more propionic acid was needed than in laboratory experiments probably because poor distribution of acid in the bale, resulted in under-treated pockets of hay where moulds tolerant to propionic acid could grow and then spread to areas that would otherwise have been adequately treated. In Dewar flasks, moulds, particularly Paecilomyces varioti and the A. glaucus group, could spread from untreated hay into hay containing 2% w/w of propionic acid. Addition of 4 or 10% of propionic acid protected adjacent untreated hay from moulding. The concentration of propionic acid necessary to prevent flasks from heating and moulding increased with thickness of the untreated layers and with water content. Redistribution of acid in the bale after treatment was slow and much variation in acid levels occurred even between adjacent 1 cm segments of grass following storage. Spontaneous heating of moulding hay could cause migration of propionic acid in hay, assisting the spread of fungi. A proprietary additive did not prevent moulding at any hay water content tested.     

Methods for testing chemical additives to'prevent moulding of hay

Three methods for testing additives for their ability to prevent moulding of hay are described. Storage of 25 g samples of hay in glass jars at 25 ^oC was useful for screening many chemicals rapidly. Dewar flasks (4–5 1) allowed testing on 500 g hay samples with sufficient insulation to allow any effects of chemicals on spontaneous heating as well as on moulding to be measured. Large drums containing 20 kg hay were used for larger scale tests with partially dried fresh, or rewetted old hay. Proprietary additives were unsuccessful at their recommended application rates and some even failed to show antifungal activity with very much larger doses. Volatile fatty acids, particularly propionic acid, and ammonium propionate were the most effective chemicals tested. The amount of propionic acid needed to prevent moulding and spontaneous heating could be defined in terms of the amount of water in the hay. Where the ratio of propionic acid to water was greater than 1–25:100 heating was rare. Ammonium propionate was slightly less effective than propionic acid against moulding. However, it lacks a pungent odour, is less volatile, less corrosive and is more pleasant and safer to handle.     

Chemicals for preventing moulding in damp hay

Fewer than one third of more than 100 chemicals tested prevented moulding when 0.5% of active ingredient was added to hay containing 35% water or, alternatively, when 0.02% of active ingredient was added with 0.2% propionic acid or ammonium propionate. Chemicals which prevented moulding in these tests when used alone included aliphatic acids with 2–6 carbon atoms, sorbic acid, short chain aldehydes and phenols, propionic acid, fully or half-neutralized with ammonia, and 8-quinolinol and its derivatives. Formic acid, aliphatic acids with 7–9 carbon atoms, longer chain aldehydes and some fungicides delayed moulding for one to two weeks. Only formaldehyde, 8-quinolinol and its derivatives, and p-nitrophenol increased the activity of 0.2% propionic acid. Although the effective doses of propionic acid, ammonium propionate, and propionic acid, half-neutralised with ammonia, were similar, there was evidence that the presence of free acid in the formulation aided redistribution to overcome undertreatment of pockets in the hay. Further tests of 2-phenyl phenol, phenyl propionate and 8-quinolinol showed that the latter was the best candidate for development. Fungi of the Aspergillus glaucus group were first to colonise most tests that failed, indicating their high degree of tolerance of a wide range of chemicals, and their value as test organisms for prospective preservatives.     

Laboratory tests of 8-quinolinol as an additive to volatile fatty acids for preserving hay and other feedstuffs

One part of 8-quinolinol in ten parts of propionic acid, either free or part-neutralised with ammonia, halved the acid required for preserving grass and lucerne hays, beans, rape seed and cereal grains containing sufficient moisture to mould. Propionic acid with 8-quinolinol delays moulding and diminishes the rate of spread of mould growth so that maximum temperatures attained are lowered and growth of thermophilic organisms is prevented. The application of 8-quinolinol and propionic acid to grass on cutting with, or without, use of formic acid as desiccant assisted inhibition of moulding especially in conjunction with ammonium propionate treatment after drying. The additive acts by inhibiting the growth of fungi which tolerate and degrade propionic and related fatty acids. The growth of two such fungi, Paecilomyces varioti and Aspergillus glaucus, is inhibited in culture by much smaller concentrations (less than 200 μM or 30 ppm) of 8-quinolinol than are required on hay, which strongly absorbs the additive and makes it less effective.     

Use of a Plasmid DNA Probe To Monitor Populations of Bacillus pumilus Inoculant Strains in Hay

We are evaluating naturally occurring isolates of Bacillus pumilus for use as microbial hay preservatives. Seven isolates of B. pumilus from hay contained a 42-kb cryptic plasmid (pMGD296). We wished to determine whether pMGD296 could be used as a molecular marker to follow populations of these isolates in hay over time. Southern blots and colony blots of 69 isolates of B. pumilus and other Bacillus spp. were probed with ³²P-labeled pMGD296. Twenty-nine probe-positive isolates were identified; of these, 28 contained a plasmid with a restriction profile identical to that of pMGD296. One isolate from untreated hay contained a 40-kb plasmid (pMGD150) that was homologous to pMGD296 but had a different restriction fragment pattern. Regions of homology between the two plasmids were identified by Southern blotting, and a 1.9-kb HindIII-PstI fragment of pMGD296 lacking strong homology to pMGD150 was cloned in pUC18. The cloned fragment hybridized only with isolates containing pMGD296 and was used to estimate populations of these isolates in treated and untreated hay.     

The relation between moisture content and moulding in cured hay

Samples of cured hay have been stored in closed containers at relative humidities of 0–95% at temperatures varying from 5 to 25° C. A curve relating equilibrium moisture content to relative humidity of the store has been constructed and the incidence of first mould growth noted. An explanation has been suggested to account for the apparent discrepancy between earlier published work concerning the onset of moulding and conditions normally prevailing on the farm. In laboratory storage experiments temperature conditions are relatively constant, whereas with hay stacked in the open air the high atmospheric humidity in winter is offset by a lowered temperature, and the higher summer temperature is accompanied by a lower moisture content in the hay.     

Effects of a Bacterial Hay Preservative (Pediococcus pentosaceus) on Hay under Experimental Storage Conditions

The abundant growth of molds and thermophilic actinomycetes in stored hay decreases its quality and can be hazardous for the producer who inhales these contaminants when the moldy hay is fed in closed barns. These microbes are responsible for a respiratory disease called farmer's lung. Products, including bacterial cultures that can be inoculated in hay, are available to prevent hay deterioration by molds and bacteria. The aim of this study was to verify the effectiveness of Pediococcus pentosaceus (a bacterial inoculant) in preventing hay deterioration at different humidity levels in a laboratory experiment. Mixtures of grasses (mostly alfalfa, timothy, and clover) placed in plastic bags were treated with the commercially available product (live culture of P. pentosaceus) at 500,000 and 5,000,000 CFU/g of hay and humidified at different levels (20, 25, 30, and 35%). Control batches of hay (untreated) were prepared at the same humidity levels. The growth of inoculated bacteria in hay, pH level, and hay deterioration were evaluated. Under these experimental conditions, the growth of P. pentosaceus was abundant only when it was inoculated in very moist hay (35% moisture), resulting in bacterium levels of 6.3 x 10(sup8) CFU/g after 30 days. This abundant growth did not prevent the pH from increasing (final pH of about 9.0), nor did it prevent molding. At lower humidity levels (20, 25, and 30%), the bacterial inoculant used did not grow and did not prevent hay deterioration.     

The feeding value of ammoniated flax straw,wheat straw and wheat chaff for beef cattle

Two experiments were conducted to assess the feeding value of ammoniated and untreated flax straw, wheat straw and wheat chaff in comparison to a mixed bromegrass/alfalfa hay. Anhydrous ammonia was applied to the crop residues at the rate of 35 kg t⁻¹ dry matter. In the first experiment, the effect of ammoniation on crude protein, acid detergent fibre (ADF), neutral detergent fibre (NDF) and acid detergent lignin (ADL), digestible organic matter in vitro and in vivo (DOM%), ADF and NDF digestibility of the crop residues was determined. In the second experiment, ammoniated flax straw, ammoniated wheat straw, ammoniated and untreated wheat chaff, each supplemented with barley, were compared to bromegrass/alfalfa hay as feed sources for wintering beef cows.Ammoniation increased the crude protein content of the crop residues ∼2-fold. Wheat straw DOM in vitro and in vivo was not increased by ammoniation. Ammoniation increased the DOM in vitro of wheat chaff from 36.3 to 46% and flax straw from 35.2 to 46.3%. The DOM in vivo increased from 53.3 to 63.4% (P < 0.05) for wheat chaff and from 33.9 to 58.4% (P < 0.05) for flax straw following ammoniation. Digestibility of ADF increased from 9.9 to 43.9% (P < 0.05) and of NDF from −0.6 to 37.9% (P < 0.05) in flax straw with ammoniation. Non-significant increases in ADF and NDF digestibility were observed for all other crop residues. Lignin content was not changed in the crop residues by ammoniation.In the winter feeding trial, young cows gained more weight than older cows (P < 0.05). Average daily gains of cows were greatest for hay followed by ammoniated flax straw, ammoniated chaff, untreated chaff and ammoniated wheat straw rations (P < 0.05). Increases in backfat in the younger cows was greatest with hay and ammoniated flax straw, followed by ammoniated chaff and ammoniated wheat straw (P < 0.05). Untreated chaff caused no increase in backfat thickness.Ammoniated flax straw (3.2 kg day⁻¹) given with barley (5.6 kg day⁻¹), is similar in feeding value to medium quality bromegrass/alfalfa hay. Furthermore, wheat chaff and ammoniated wheat chaff show good potential as alternatives to hay in winter feeding.     

ABA、NAA诱导水稻胚性愈伤组织的研究

ABA和NAA联合使用能有效地诱导水稻原生质体再生的愈伤组织向胚性发展。通过液体浅层培养由原生质体得到的愈伤组织,在含ABA和NAA的N_6培养基上培养一段时间,可以诱导原来呈非胚性状态的愈伤组织形成胚性愈伤组织,并在含ZT的N_6分化陪养基上产生绿点。通过对这两种愈伤组织的生化分析,表明二者在游离氨基酸、DNA、RNA、核酸及蛋白质含量等方面,特别是SDS-PAGE谱带存在明显的差异,其细胞的形态与结构也有显著差别,其中经ABA NAA诱导后的愈伤组织其细胞形态与结构特征与来源于种胚的胚性愈伤组织基本类似,所分析的生化指标也大多数相近。结果表明,ABA和NAA联合使用得当,能促进形成胚性愈伤组织。     

Effects of an artificial hay aroma and compound feed formulation on feed intake pattern,rumen function and milk production in lactating dairy cows

The Kempen system is a dairy feeding system in which diet is provided in the form of a compound feed (CF) and hay offered ad libitum. Ad libitum access to CF and hay allows cows in this system to achieve a high DM intake (DMI). Out of physiological concerns, the voluntary hay intake could be increased and the consumption pattern of CF could be manipulated to maintain proper rumen functioning and health. This study investigated the effects of an artificial hay aroma and CF formulation on feed intake pattern, rumen function and milk production in mid- to late-lactating dairy cows. Twenty Holstein–Friesian cows were assigned to four treatments in a 4 × 4 Latin square design. Diet consisted of CF and grass hay (GH), fed separately, and both offered ad libitum, although CF supply was restricted in maximum meal size and speed of supply by an electronic system. Treatments were the combination of two CF formulations – high in starch (CHS) and fibre (CHF); and two GH – untreated (UGH) and the same hay treated with an artificial aroma (TGH). Meal criteria were determined using three-population Gaussian–Gaussian–Weibull density functions. No GH × CF interaction effects on feed intake pattern characteristics were found. Total DMI and CF intake, but not GH intake, were greater (P < 0.01) in TGH treatment, and feed intake was not affected by type of CF. Total visits to feeders per day, visits to the GH feeder, visits to the CF feeder and CF eating time (all P < 0.01) were significantly greater in cows fed with TGH. Meal frequency, meal size and meal duration were unaffected by treatments. Cows fed CHF had a greater milk fat (P = 0.02), milk urea content (P < 0.01) and a greater milk fat yield (P < 0.01). Cows fed TGH had a greater milk lactose content and lactose yield (P < 0.05), and milk urea content (P < 0.01). Cows fed TGH had smaller molar proportions of acetic acid and greater molar proportions of propionic acid compared with UGH. In conclusion, treatment of GH with an artificial aroma increased CF intake and total DMI, but did not affect hay intake. Additionally, GH treatment increased the frequency of visits to both feeders, and affected rumen volatile fatty acid profile. Type of CF did not affect meal patterns, ruminal pH, nor fermentation profiles.     

Simultaneous production of cellulase complex and glucose isomerase by Streptomyces flavogriseus

Summary Fermentations of Streptomyces flavogriseus were carried out at 30° C on media containing either Avicel, hay or acid hay hydrolysate as the principal carbon source. Under these conditions the strains produced simultaneously the enzymes of the cellulase complex as well as glucose isomerase. The enzyme activities were induced by hay, hay extract and D-xylose.     

The sealed storage of moist flax with and without the use of chemical preservatives

The suitability of ensilage as a means of preserving flax was investigated in a series of experiments in which 400 kg round bales of fresh flax were sealed in polyethylene film or plastic wrapped, with or without the addition of formic acid at 2.5 litre t^-1 or formalin at 5.6 litre t^-1 at the time of baling. Plastic wrapping provided a more effective seal than the bags which were easily punctured by the flax roots resulting in moulding and deterioration of the flax. Where the seal was not broken untreated flax underwent a clostridial fermentation and the pH fell to about 4.8. Cellulolytic activity degraded the flax fibre over a period of 3 to 6 months. The addition of formic acid reduced the cellulolytic activity provided the seal was not broken. In an experiment with 4 kg batches of flax of 65%, 40% or 25% MC sealed in polyethylene film, the addition of formic or propionic acids at 20 g kg^-1 DM did not prevent moulding and deterioration, but both NH₃ and SO₂ at 40 g kg^-1 DM preserved the physical structure of the flax. The NH₃ darkened the flax and made it pliable and unscutchable while the SO₂ bleached it and preserved the fibre without microbiological deterioration. The presence of acids on the moist stored flax appeared to inhibit the progress of normal water retting.     

Use of retinoic acid for the analysis of dermal-epidermal interactions in the tarsometatarsal skin of the chick embryo

Feet of chicks are normally covered with scales. Injection of retinoic acid into the amniotic cavity of 10-day chick embryos causes the formation of feathers on the foot scales. To elucidate whether retinoic acid affects primarily the epidermis or the dermis, heterotypic dermal-epidermal recombinants of tarsometatarsal skin were tested as to their morphogenetic capacity, when grafted to the chick chorioallantoic membrane. Recombinants involving treated epidermis and untreated dermis formed feathered scales, while the reverse recombinants of untreated epidermis and treated dermis led to the formation of scales only. Likewise the association of treated tarsometatarsal dermis with untreated epidermis from a non-appendage-forming region (the midventral apterium) resulted in the formation of scales only. These results show that retinoic acid affects primarily the epidermis. Further insight into the mechanism of dermal-epidermal interaction was gained by heterotopic recombinations of early (8.5- and 10-day) untreated tarsometatarsal dermis with epidermis from the midventral apterium. These recombinants formed scales, proving that tarsometatarsal dermis is endowed with scale-forming properties as early as 8.5 days of incubation. Finally, it is concluded that retinoic acid acts on the chick foot epidermal cells by temporarily inhibiting their scale placode-forming properties, allowing their latent feather placode-forming properties to be expressed.     

Differences in faecal bacteria populations and faecal bacteria metabolism in healthy adults and celiac disease patients

Differences in the intestinal microbiota between children and adults with celiac disease (CD) have been reported; however, differences between healthy adults and adults with CD have not been clearly demonstrated. The aim of this study was to evaluate the differences in the intestinal microbiota between adults with CD and healthy individuals. Microbial communities in faecal samples were evaluated by PCR-denaturing gradient gel electrophoresis (DGGE) and gas-liquid chromatography of short chain fatty acids (SCFAs). The study group included 10 untreated CD patients, 11 treated CD patients and 11 healthy adults (in normal gluten diet and in GFD). UPGMA clustered the dominant microbial communities of healthy individuals together and separated them from the dominant microbial communities of the untreated CD patients. Most of the dominant microbial communities of the treated CD patients clustered together with those of healthy adults. The treated CD patients showed a reduction in the diversity of Lactobacillus and Bifidobacterium species. The presence of Bifidobacterium bifidum was significantly higher in untreated CD patients than healthy adults. There was a significant difference between untreated CD patients and healthy adults, as well as between treated CD patients and healthy adults, regarding acetic acid, propionic acid, butyric acid, and total SCFAs. In conclusion: healthy adults have a different faecal microbiota from that of untreated CD patients. A portion of the treated CD patients displayed a restored "normal" microbiota. The treated CD patients significantly reduce the Lactobacillus and Bifidobacterium diversity. Healthy adults have a different faecal SCFAs content from that of CD patients.     

Uric acid concentration in saliva and its changes with the patients receiving treatment for hyperuricemia

To date, few studies have examined uric acid in saliva or dental calculus. The purpose of this study is to examine the uric acid concentration in saliva and serum. Saliva and blood samples were collected from 244 participants. We divided them into four groups: untreated or treated group in normal or abnormal serum uric acid concentration groups. Within the untreated group, Pearson??s correlation coefficient was used to examine the correlation between salivary and serum uric acid concentrations. We compared uric acid concentrations between saliva and serum, or between untreated and treated groups using the paired or unpaired student??s t-test. In the untreated group, uric acid concentrations in saliva and serum were significantly and positively correlated (r?=?0.503, P?<?0.01). Within the untreated group, those with abnormal serum uric acid concentrations had significantly higher uric acid concentrations in serum and saliva compared to those with normal serum uric acid concentrations (P?<?0.01). Within the untreated group, uric acid concentrations in serum were significantly higher than that in saliva (P?<?0.01). Uric acid concentrations in saliva of the treated group were significantly higher than that of the untreated group (P?<?0.01). Within the treated group, uric acid concentrations in saliva were significantly higher than that of serum, particularly in users of benzbromarone (P?<?0.01). Uric acid concentrations in saliva were lower than that in serum among non-users of benzbromarone. In contrast, uric acid concentrations in saliva of patients taking benzbromarone were higher than that in serum. We surmise that URAT1 may influence uric acid excretion in the salivary gland.     

Role of Disulphide Bonds in the Resistance of Bacillus cereus Spores to Gamma Irradiation and Heat

S ummary . Spores of Bacillus cereus were treated with thioglycollic acid which ruptures at least 10–30% of the spore disulphide bonds by reducing them to thiol groups. The treated spores were still viable and were sensitive to lysozyme but remained as resistant to γ-irradiation and to heat as untreated spores. Neither treated nor untreated spores were sensitized to irradiation by reagents which block thiol groups. The results did not indicate that the high content of disulphide bonds in spore coat protein protects spores against inactivation by irradiation or heat.     

Effect of phenol on lipid and fatty acid profile of Xanthomonas oryzae pv. oryzae

Effect of phenol on total lipid and fatty acid composition of Xanthomonas oryzae pv. oryzae, the causal agent of bacterial blight of rice (Oryzae sativa) was studied. Lipid level was low in phenol treated cells. Number of fatty acids detected from phenol treated cells was more than those found in untreated cells as revealed by Gas chromatography. Pentadecanoic acid (C15:0), linolenic acid (C18:3) and behenic acid (C22:0) were present only in the treated cells. Palmitic acid which is usually found in bacteria was not detected both in control and treated cells.     

Critical analysis of the effect of metal ions on gluconic acid production by Aspergillus niger using a treated Indian cane molasses

Gluconic acid fermentation by Aspergillus niger has been investigated using untreated and treated Indian cane molasses. The yield of gluconic acid was found to be reduced using an untreated molasses medium compared to a defined medium. Hence, molasses was subjected to various pretreatment techniques. Pretreatment reduced the levels of various cations and anions. As the synthesis of gluconic acid has been observed to be influenced more by cations than anions, the effect of various metal ions, viz., copper, iron, zinc, manganese, calcium, and magnesium on the yield of gluconic acid has been critically examined in both untreated and treated cane molasses. These results have been compared with a defined medium. The yield of gluconic acid was influenced more by a combination of metal ions rather than individual ions. Potassium ferrocyanide treatment gave the most promising results compared to other treatment techniques.     

Characterisation of different types of hay by solid-phase micro-extraction-gas chromatography mass spectrometry and multivariate data analysis

The volatile organic compounds of different ground hay samples from Austria, Italy and Switzerland were collected at 50 degrees C on a Supelco Carbowax Divinylbenzene headspace solid-phase microextraction fibre, separated by capillary gas chromatography on an HP5-ms column running a temperature programme and using helium as carrier gas, detected with a mass sensitive detector and studied with principal component analyses after autoscaling selected variables. The analytes, mainly mono- and sesquiterpenes, were able to cluster differences resulting from the site of production. Coumarin can be used to differentiate hay grown north and south of the main chain of the Alps. Acetic acid is appropriate for distinguishing between hay from Kastelruth and Passeier Valley, two South Tyrolean regions. The average linalool content in aftermath is higher than in hay.     

Influx and efflux of inorganic phosphate in sweet potato slices. effects of abscisic acid on bi-phasic kinetics

Influx and efflux of inorganic phosphate was determined in freshly cut and “aged” slices of sweet potato tubers, in the presence or absence of abscisic acid. Slices aged in the phytohormone took up considerably less phosphate than did the control slices. No difference in the rates of uptake of phosphate by the fresh tissue was observed. Kinetics of uptake of the aged untreated slices, proved to be bi-phasic. This was not the case for the treated slices. Neither the treated nor the untreated uptake curves for the fresh slices were bi-phasic. Efflux of phosphate from the slices aged in abscisic acid was greater than from the untreated slices. The results strongly suggest an effect of abscisic acid on the cell membrane.