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An Italian ryegrass and hybrid ryegrass sward was harvested on 11 May 1994. The mean dry‐matter (DM) content of the herbage was 197 g kg–1 fresh matter (FM), and mean nitrogen and water‐soluble carbohydrate contents were 20 and 272 g kg–1 DM respectively. Approximately 72% of total nitrogen (TN) was in the form of protein‐nitrogen. The herbage was treated with either no additive, formic acid (3·3 l t–1) (Add‐F, BP) or inoculant (2·3 l t–1) (Live‐system, Genus) and ensiled in 100 t silos. Changes in effluent composition with time showed that silage fermentation and protein breakdown were delayed by treatment with formic acid. Formic acid and inoculant treatments also inhibited amino acid catabolism during ensilage. All silages were well fermented at opening with pH values < 4·0 and ammonia‐N concentrations of ≤ 50 g kg–1 TN after 120 d ensilage. Treatment had an effect on protein breakdown as measured by free amino acid concentration, with values of 21·5, 18·2 and 13·2 mol kg–1 N at opening (191 d) for untreated, formic acid‐treated and inoculated silages respectively. Amino acid catabolism occurred to the greatest extent in untreated silages with significant decreases in glutamic acid, lysine and arginine, and increases in gamma amino butyric acid and ornithine. The silages were offered ad libitum without concentrate supplementation to thirty‐six Charolais beef steers for a period of 69 d (mean live weight 401 kg). Silage dry‐matter intakes and liveweight gains were significantly (P < 0·05) higher on the treated silages. Silage dry‐matter intakes were 7·42, 8·41 and 8·23 kg d–1 (s.e.d. 0·27) with liveweight gains of 0·66, 0·94 and 0·89 kg d–1 (s.e.d. 0·058) for untreated, formic acid‐treated and inoculated silage‐fed cattle respectively. In conclusion, additives increased the intake of silage and liveweight gain by the beef steers, and it is suggested that this may be caused in part by the amino acid balance in these silages.  相似文献   

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The main object of the experiment was to assess the effect of the relative proportion of non-protein nitrogen (NPN) to total nitrogen in silage on digestion in the sheep. Four unwilted perennial ryegrass silages were made with the addition of formic acid at 0, 2·2, 4·2 and 5·2 litres t-1 to provide foods with NPN proportions reducing from 0·26 to 0·20 of the total N. The digestion of the silages was studied in a 4 × 4 Latin Square experiment with sheep cannulated in the rumen, proximal duodenum and terminal ileum.
Results for organic matter (OM), cellulose and N showed no major difference between silages in their digestion in the rumen, small intestine and caecum and colon, though small differences ( P <0·25) in rumen fermentation pattern and in the proportion of digestible OM disappearing in the small intestine were observed. Concentrations of ammonia N in the rumen and rates of rumen bacterial protein synthesis did not differ significantly between silages and there were no treatment effects on the passage of individual amino acids to the small intestine. The results indicate that the proportions of NPN to total N in the silages examined had little influence on the efficiency of silage N utilization in the rumen or on the passage of undegraded dietary protein to the small intestine.  相似文献   

5.
A range of samples embracing 14 varieties from different localities within the United Kingdom, many grown with the application of different known levels of nitrogenous fertilizer, were submitted to proximate analysis, some analysed for total amino acid composition and some evaluated nutritionally in near-practical dietary mixtures with various protein concentrates.Location of growth was found to be more important than level of nitrogen application in determining the protein content of the harvested grain. Small differences in amino acid composition were noted, and there appeared to be a progressive decline in lysine content with increasing nitrogen level in the seed.Significant differences in nutritive value between the barleys were detectable in mixtures of each with protein concentrates, and in general discrimination between them was better if the accompanying concentrate was of poor quality e.g. groundnut. With fish meal differences between the barleys were well marked. The differences found were real and reproducible, and the results indicated that particular barleys differed in their ability to complement soya bean or groundnut.
Zusammenfassung Es wurden Proben von 14 Getreidesorten untersucht, von verschiedenen Standorten Großbritanniens, die zumeist mit verschieden hohen Stickstoffgaben gedüngt waren. Die Untersuchung der Proben bezog sich teils auf die Gesamt-Aminosäuren und teils auf den ernährungsphysiologischen Wert der Proben in praxisnahen Diät-Mischungen mit verschiedenen Protein-Konzentraten.Der Protein-Gehalt des geernteten Getreides ist stärker vom Standort abhängig als von der Höhe der Stickstoffdüngung. Es wurden geringe Unterschiede in der Aminosäuren-Zusammensetzung festgestellt, und es scheint, daß bei fortschreitender Zunahme des Stickstoffgehaltes in den Getreidekörnern der Lysingehalt abnimmt.Signifikante Unterschiede im ernährungsphysiologischen Wert verschiedener Gerstensorten waren in Mischungen jeder einzelnen mit Proteinkonzentraten nachweisbar, wobei die Unterschiede im allgemeinen deutlicher wurden, wenn die zugemischten Konzentrate von geringerer Qualität waren, z.B. Erdnuß. Mit Fischmehl versetzt traten die Unterschiede zwischen den Gerstensorten weniger deutlich hervor. Die gefundenen Werte waren reproduzierbar, und die Ergebnisse weisen darauf hin, daß insbesondere die Gerstensorten, in ihrem Ergänzungswert für Sojabohne oder Erdnuß differieren.

Résumé 14 lots de céréales, provenant de diverses stations de Grande Bretagne, et soumis à des taux différents de fumures azotées, ont été étudiés. Chaque lot était analysé au point de vue du taux d'aminoacides, et au point de vue nutritionnel, dans des mélanges analogues à ceux de la pratique, à des taux protéiques variés.Le taux de protéines d'une céréale dépend davantage de la station, que du taux de fumure. De faibles différences dans les taux d'aminoacides ont été observés; il semble que le taux de lysine décroisse lorsque croit le taux d'azote du grain.Des différences significatives dans la valeur nutritionnelle de diverses variétés d'orges apparurent, dans des mélanges de ces variétés avec des concentrés de protéines, ces différences étaient plus nettes avec des concentrés de plus médiocre qualité, par exemple formé de tourteau d'arachide. Les formés de poison ne furent pas apparaitre aussi nettement les différences parmi diverses qualité d'orges. Les résultats sont bien reproductibles, la conclusion en est que les variétés d'orges n'ont pas toute la même valeur comme supplément du tourteau de soya ou d'arachide.


Paper presented at the conference of the International Association for Quality Research on Food Plants (CIQ) held in common with the Deutsche Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) e.V. (DGQ) in Berlin on 6th October 1972.  相似文献   

6.
Groundnut mutants TG-8, TG-9, TG-17 and TG-18 induced by -irradiation differed in fatty acid composition from their parent Spanish Improved. All the mutants had lower linoleic and higher oleic than Spanish Improved. TG-18 had lower oleic and higher linoleic as compared with TG-8, TG-9 and TG-17. Palmitic acid in TG-18 and Spanish Improved was higher than other mutants. Oil stability as judged by oleic to linoleic ratio was substantially higher for mutants as compared with their parent.Amino acid composition of groundnut mutant proteins differed from Spanish Improved. In general mutants had higher contents of lysine, histidine, proline, phenylalanine and tryptophan and lower contents of threonine, serine and methionine. The first limiting amino acid was tryptophan in Spanish Improved, threonine in TG-8, TG-9 and TG-17 and Valine in TG-18. Essential amino acid contents for all except methionine, valine and threonine per grain flour were higher in all the mutants as compared with their parent.  相似文献   

7.
A comparison was made of the digestibility, voluntary intake and concentration of N in faecal organic matter in castrated male sheep and non-lactating cows offered herbage ad libitum. The sheep ate 22% more herbage DM per kg liveweight than the cows. In general, the sheep and cows digested the organic matter of the herbage to the same extent, although on two occasions significantly higher digestibilities were observed in cows than in sheep. Similar concentrations of N in faecal organic matter in sheep and cows were matched by similar digestibilities of herbage organic matter. Regression equations relating herbage organic matter digestibility to faecal N concentration were not significantly different between sheep and cattle.  相似文献   

8.
A series of comparisons was made of the bite rates of fistulated and non-fistulated cattle and sheep, grazing four grassy hill plant communities over four years. Both bite rates and grazing times were recorded on two occasions. Comparative observations were also made on faecal cuticle concentrations on one grassy and one dwarf shrub community and on faecal ash, nitrogen (N) and acid detergent fibre (ADF) concentrations throughout one year.
Faecal N concentrations were slightly but consistently higher in fistulates than in non-fistulates, but faecal ADF and ash concentrations and the relative proportions of faecal cuticle fragments were similar and did not indicate differences in either diet composition or digestive efficiency. Bite rates did not differ significantly between fistulates and non-fistulates, except on the two occasions when fistulates carried Vibracorders to measure grazing time without preliminary training, and grazing times did not differ significantly. There were significant differences between cattle and sheep in most variables.
On the basis of this evidence, there is no reason to expect that fistulated and non-fistulated animals of similar history and nutritional background will differ in grazing behaviour or diet composition.  相似文献   

9.
Two 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.  相似文献   

10.
When the rate of N fertilization was increased from 36 lbs/acre to 336 lbs/acre, the total amino acid pool in the tubers almost doubled. The increases for individual amino acids ranged from none (tyrosine) to 2.7 fold (glutamic acid + glutamine). Aspartic acid and glutamic acid and their corresponding amides constituted the bulk of the free amino acid pool, and increased from 55% to 65% with increasing fertilization. Lysine increased by 1.9 times and methionine by 1.4 times with increasing nitrogen fertilization but the relative proportions of lysine in the pool remained unchanged and methionine decreased from 2.2% to 1.6%. The amino acids could be grouped into four categories with respect to their response to increasing nitrogen levels: those giving almost no response (tyrosine and phenylalanine), those giving full response at low levels of N (amino acids of the serine and pyruvate families), those giving full response at a higher but intermediate level (amino acids of the aspartate family), and those which responded to the highest level of fertilization (glutamic acid + glutamine). The gas chromatographic method used in this study for the analysis of free amino acids is discussed.  相似文献   

11.
The aim of this work was to investigate the effects of feeding sheep with silage mixtures containing bioactive legumes on intake and digestive parameters. The bioactive legumes used were sainfoin (SF, Onobrychis viciifolia) and red clover (RC, Trifolium pratense), which contain condensed tannins (CT) and polyphenol oxidase respectively. Five treatments were assigned to two groups of sheep according to a replicated 5 × 5 Latin square design. The five types of silages tested were, on a dry matter (DM) basis: pure timothy grass silage (Phleum pratense, control, T), three binary mixtures of T‐SF, T‐RC and RC‐SF (500 g/kg each) and a ternary mixture of T‐RC‐SF (500, 250 and 250 g/kg respectively). The daily voluntary DM intake of silage mixtures containing both SF and RC was greater than for pure T silage, while the presence of SF resulted in lower organic matter digestibility compared to pure T. The rumen disappearance rate measured in situ increased linearly with the presence of SF and RC in silage. The nitrogen (N) digestibility was greater for pure T and T‐RC than for T‐SF, and the amount of N retained daily by the animals was greater for RC‐containing silages than for T and T‐SF. The methane (CH4) yield was greater for pure T than for the silage mixtures containing SF. We conclude that the presence of RC in silage could boost performances through intake and N retention, while SF‐based mixtures appear to have reduced negative environmental impacts through the reduction of CH4 emissions.  相似文献   

12.
Timothy–meadow fescue herbage was ensiled with formic acid (FA) (expressed as 100% solution) at the rates of 0, 2, 4 or 6 L t?1. The silages were fed along with concentrates to bulls fitted with cannulae in the rumen and duodenum. The ration comprised grass silage (700 g kg?1), barley (240 g kg?1) and rapeseed meal (60 g kg?1). The application rate of FA had no effect on the site or extent of the digestion of dietary organic matter (OM) and neutral‐detergent fibre. The flow of total N at the duodenum increased linearly (P < 0·05) with application rate of FA, reflecting mainly an increased (P < 0·01) flow of microbial N. The apparent efficiency of net microbial protein synthesis in the rumen increased (P < 0·05), the proportion of propionate in the volatile fatty acids (VFA) in the rumen was not affected (P > 0·05) but that of butyrate increased (linear and quadratic effects, P < 0·01) with increasing rate of FA. It is concluded that an increase in the rate of FA at ensiling leads to a higher utilization of energy and/or protein‐yielding substrates for rumen microbes and to a modified rumen VFA pattern with an increased proportion of butyrate.  相似文献   

13.
Seven varieties of buckwheat, two Indian selections (F. esculentum, F. tetaricum) and five from Poland (Czernoplodna, Hruszowska, Jubilejna, Emka and Iskra) were cultivated under North Indian conditions and analysed for their protein and amino acid composition. The present studies revealed that European selections can also be successfully cultivated in India. Buckwheat is a good source of lysine, and some other essential amino acids.  相似文献   

14.
The seeds of five different species ofAcacia, twoAlbizzia, twoErythrina and two species ofMucuna were analysed for their protein and amino acid composition. Some of these seeds are comparable to a popular food legume,Cicer arietinum, in protein and amino acid composition.  相似文献   

15.
In an experiment, involving twelve male cattle (initially 235 kg live weight), the effects of applying lactic acid bacteria [Lactobacillus plantarum; 109 colony-forming units (g fresh silage)?1] to grass silage, immediately prior to that silage being fed, on dry-matter (DM) intake of the silage, degradability of nitrogen (N) and fibre in the rumen, total tract digestibility and composition of rumen fluid in the animals were examined. A grass silage, which had been made from the primary growth of a predominantly perennial ryegrass sward, was offered as the sole diet. The inoculant was applied to the silage at the rate of 2 g of freeze-dried powder reconstituted in 12 ml of water (kg fresh silage)?1 immediately prior to that silage being fed and an equivalent amount of water was applied to the silage in the control treatment. The two diets were compared in a change-over design. The silage was well preserved, having a pH and concentrations of ammonia N and butyrate of 3.72, 74 g (kg total N)?1 and 0.11 g (kg DM)?1 respectively. Application of the inoculant significantly increased true protein, acid-insoluble N and water-soluble carbohydrate concentrations (P < 0.001) in the diet. Silage DM intake was not significantly increased (P= 0.072) by this of inoculant treatment, which had no significant effect (P > 0.05) on rumen degradability or total tract digestibility of DM, N, neutral detergent fibre or modified acid detergent fibre. Rumen pH, ammonia concentration or the molar proportions of volatile fatty acids were not altered (P>0.05) by inoculant treatment. It is concluded that application of the inoculant to the silage prior to silage being fed did not significantly affect silage DM intake, total tract digestibility, or degradability or fermentation in the rumen of cattle offered grass silage as the sole diet. It is also concluded that the results of this experiment provide no evidence that the mode of action of L plantarum, applied as an additive to grass at ensiling in previous studies, is through ‘direct’ effects in the rumen.  相似文献   

16.
Russet Burbank, Norchip, Kennebec, White Rose, Red La Soda and Lenape tubers were sampled at harvest, after storage for 2 and 4 mo at 7 C, and after 3 wk at 20 C following each storage treatment. Freeze-dried tissue from the bud-end, stem-end and core was analyzed for total, and free amino acid nitrogen, and for monophenolase, polyphenolase, peroxidase, and catalase activities. Significant differences among cultivars and among different parts of the tuber were found for all nitrogen fractions and all enzyme activities. Storage treatments significantly changed the total and free amino acid nitrogen contents and polyphenolase, peroxidase, and catalase activities. When compared for total nitrogen content and catalase activity, differences among different parts of the tuber which were statistically significant were similar in all cultivars. However, when compared for free amino acid content, and monophenolase, polyphenolase and peroxidase activities, differences among different parts of the tuber which were statistically significant were dependent upon which cultivar was examined. The differences among cultivars which were statistically significant for all nitrogen fractions and all enzyme activities, except peroxidase, were not significantly changed by storage treatment. The differences among different parts of the tuber which were statistically significant for quantity of both nitrogen fractions and for all enzyme activities were not significantly changed by storage.  相似文献   

17.
An experiment was designed to examine the effects of partially replacing extensively fermented grass silage with varying proportions of fresh grass (0, 0–33, 0–67 and 100) on rumen fermentation, degradation of dry matter (DM) and rate of outflow of liquid and particulate phases from the rumen with four mature Limousin steers. The fresh grass had a higher pH and water-soluble carbohydrate and lower ammonia-N and lactic acid concentrations than the silage. Partial replacement of silage with fresh grass resulted in a reduction in rumen ammonia concentration, and in the proportion of rumen propionate, i-butyrate and n -valerate and an increase in the proportion of rumen acetate and in both die particulate and liquid outflow rates from the rumen. These changes in rumen fermentation parameters could account for increases in animal performance in situations in which grass silage is partially replaced with fresh grass.  相似文献   

18.
Forty‐eight high‐yielding dairy cows of the Swedish Red breed were used to examine the effects of providing pea–oat silage (P), grass–clover silage (G) and a 0·50:0·50 mixture of the silages (M) ad libitum in diets with two concentrate levels (7 or 10 kg d?1). A 9‐week experiment, including a 2‐week pre‐experimental period in which the cows were all fed the same diet, and an in vivo apparent digestibility study were conducted comparing the six dietary treatments (M7, M10, P7, P10, G7, G10). Intake and digestibility of the diets and milk production and live weight of the cows were measured. The G silage [11·3 MJ ME kg?1 dry matter (DM)] was first‐cut grass herbage wilted for 24 h prior to addition of an additive, containing formic acid, propionic acid and ammonia, at 4 L t?1 fresh matter (FM). The P forage was cut when the peas were at pod fill and ensiled directly with 6 L t?1 FM of the same additive. The main hypothesis tested, that cows fed the M silage would produce more milk than the cows fed either the P or the G silages, was confirmed. The cows fed the M7 dietary treatment had similar milk yield and milk composition to cows offered the M10, G10 and P10 dietary treatments, and cows offered the G7 and P7 dietary treatments had lower milk and milk protein yields. This suggested that a mixed ration of pea–oat bi‐crop and grass–clover silage has a concentrate‐sparing effect, and that the use of pea–oat bi‐crop and grass–clover silage as a mixed ration for high‐yielding dairy cows can be recommended.  相似文献   

19.
Twenty ley and whole‐crop samples were analysed before and after ensiling to determine the proportion of dry matter (DM) that could be accounted for by the sum of 12 chemical assays for ash, ash‐excluded‐amylase‐treated neutral detergent fibre (aNDFom), starch, water‐soluble carbohydrates (WSC), pectin, crude protein (CP), CP in aNDFom (CPndf), ammonia, crude fat, phenolics, plant organic acids and liquid fermentation products (acids and alcohols). Crop components, utilized during silage fermentation and the possibility of predicting silage composition from that of the crop, were also investigated. Samples consisted of timothy and red and white clover, harvested at early and late maturities in two cuts per maturity and of whole‐crop barley, wheat and maize, harvested at early, intermediate and late stages of maturity. Ley crops were wilted to reach a DM content of approximately 400 g/kg, whereas whole crops (WC) were not wilted (151–757 g DM/kg) before ensiling. The average sum of analytes was 1022 and 981 g/kg DM for crops and silages respectively. An overall closeness to complete recovery indicates that no major plant components were missing from the analyses. Relative proportions of pectin, plant organic acids and phenolics, which are rarely analysed, were approximately 60:40:2 (w/w). Ash, aNDFom, crude fat and CP were almost completely recovered after ensiling, whereas partial metabolism reduced recoveries of starch (81%), CPndf (62%), plant organic acids (65%), pectin (64%) and WSC (29%). Only the four analytes with high silage recoveries could be reasonably well predicted from parent crop levels with mean prediction error from 0.065 for aNDFom to 0.167 for crude fat.  相似文献   

20.
The effects of forage matting on rate of grass drying and silage fermentation, digestibility, and intake were examined using perennial ryegrass swards. Treatments compared were: forage mats, where grass was processed through a laboratory scale macerator prior to matting and wilting to 228 g dry matter (DM) kg?1 (FM treatment); unconditioned grass which was direct ensiled at 163 g DM kg?1 (DE treatment); unconditioned grass which was wilted for the same period as FM to 213 g DM kg?1 (UC treatment); unconditioned grass which was wilted to 234 g DM kg?1 (UC25, treatment). All forages were dried on black plastic sheeting. For each treatment a total of approximately 80 kg grass DM was ensiled in seven 290 I plastic bins for 136 d prior to feeding to wether sheep. A further total of 14 kg grass DM from each treatment was ensiled in twenty-one plastic pipes (152 mm diameter, 762 mm long) to give a total of 84 pipes. Rate of silage fermentation was determined by destructively sampling pipes following 1, 2, 4, 6, 13, 20 and 50 d of ensilage. Over the mean wilting period of 6·9 h, grass from the FM treatment dried significantly faster (P < 0·001) and required less solar energy per unit of moisture loss than unconditioned grass. The rate of grass drying was highly correlated with solar radiation. The FM treatment did not influence the rate or extent of silage fermentation. The intakes and digestibilities of FM, UC and UC25 were not significantly (P < 0·05) different from each other but were higher than for the DE treatment (P < 0·05 for digestibility and NS for intake). In Northern Ireland it is unlikely that there will be sufficient solar radiation to allow forage mats to be made, wilted to a level to prevent effluent production and harvested within one working day. Further work is required to optimize mat-making technology for more rapid drying and to determine the effect of adverse weather on nutrient losses from mats.  相似文献   

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