首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 15 毫秒
1.
In 2 two-factorial experiments, each conducted on 80 growing male rats, the effects of substituting 10% raw potato starch (PS), pectins (PEC), or cellulose (CEL) for wheat starch (WS) and the addition of tannic acid to WS (WSTA) were studied using diets differing in protein quality. Casein unsupplemented or supplemented with DL-methionine and gluten unsupplemented or supplemented with lysine, methionine and tryptophan were used as protein sources in Experiment 1 and 2, respectively. Parameters indicative of caecal fermentation intensity (pH, acetic, propionic and butyric acid contents, digesta and tissue weight) and of protein metabolism (urea blood concentration, faecal and urinary nitrogen excretion) were determined. Ten-day balance experiments were preceded by a 10-day adaption period to respective carbohydrates given in a diet containing balanced protein. In both experiments the type of carbohydrates affected the caecal concentration of individual and total SCFA and other parameters of fermentation intensity. Pectins and potato starch were fermented more intensively than cellulose. Faecal N excretion was increased by all carbohydrates substituted for cereal starch, and by tannic acid. Urinary excretion was greater on CEL than on PEC and WSTA containing casein and on other diets containing gluten. In both experiments urinary N excretion was the lowest on PEC diets. Protein quality had the greatest effect on apparent biological value and net protein utilization but all indices of protein utilization were also affected by carbohydrates. It is concluded that not only the amount of N excreted in faeces but also in urine is affected by the type and fermentability of carbohydrates.  相似文献   

2.
1. The effect of washing out the caecal contents on nitrogen utilisation and nitrogen excretion were examined in Single Comb White Leghorn cockerels fed on a 50 g/kg protein diet supplemented with urea. 2. Flushing out the caecal contents with saline in caecally ligated chickens produced a significantly increased nitrogen balance and increased nitrogen utilisation (P<0.05). 3. Washing out the caecal contents significantly decreased uric acid excretion but the treatment had no effect on urea and ammonia excretion. 4. Caecal bacterial contents were significantly decreased by caecal ligation and decreased further by washing out the caecal contents. 5. It is concluded that nitrogen metabolism in chickens is affected by possible changes in caecal fermentation produced by preventing substances from urine and digesta from entering the caeca.  相似文献   

3.
The aim of the study was to determine and compare the endogenous ileal excretions of nitrogen and amino acids under protein-free and peptide alimentation by the dog and rat. Two diets were prepared, one that was devoid of protein and the other containing 23% enzyme hydrolysed casein. Chromic oxide was included in the diets as an indigestible marker. A total of 10 mixed breed dogs were fed hourly either a protein-free or enzymatically hydrolysed casein diet for a total of 10 days. A faecal sample was obtained from each dog on day 9 while digesta was obtained from the terminal 20 cm of the ileum directly after euthanasia on day 10. A total of 12 8-week-old Sprague-Dawley rats received the same diets as the dogs. A faecal sample from each rat was obtained on day 7 while ileal digesta samples were obtained on day 8. The endogenous ileal excretions of most amino acids were greater in the dogs and rats that received the enzymatically hydrolysed casein diet compared with those receiving the protein free diet. Whereas the pattern of endogenous amino acid excretion was similar in the rats and dogs, the dogs excreted a significantly greater amount of nitrogen (1.91 vs. 2.27 and 1.63 vs. 4.12 g/kg dry matter intake for the protein-free and peptide alimentation method, respectively) and all amino acids except for glycine, isoleucine and leucine. Endogenous ileal amino acid excretions are higher in dogs compared to omnivorous animals such as rats and pigs but similar to the carnivorous cat.  相似文献   

4.
Nine barrows with an average initial weight of 60 kg were fitted with simple T-cannulas at the distal ileum. The animals were fed four different protein-free diets according to an incomplete latin square design. Diet 1 (control diet) consisted of 79.7% cornstarch, 10% sucrose, 3% Alphafloc (a source of cellulose), 3% canola oil and a vitamin-mineral premix. Diets 2, 3 and 4 contained, respectively, 4% pectin, an additional 7% cellulose and an additional 10% canola oil, each included at the expense of cornstarch. Feces were collected during 3 d following a 7-d adaptation period. Thereafter, digesta were collected during two 24-h periods with a 24-interval between periods. The pigs were fed 800 g of feed twice at 0800 and 2000. Added pectin increased (P less than .05) the recovery of endogenous protein in ileal digesta from 19.8 diet (diet 1) to 24.0 g per kg dry matter intake. This increment was largely due to increases (P less than .05) in glycine and proline from 1.9 to 2.4 and from 6.2 to 8.4 g per kg dry matter intake, respectively. In feces, only added cellulose increased (P less than .05) excretion of endogenous protein (8.4 vs 11.1 g/kg DM intake) and of most amino acids. Including additional fat did not affect the quantity of endogenous protein and amino acids recovered in ileal digesta or feces. Small but significant differences (P less than .05) were observed in the amino acid composition of endogenous protein recovered in ileal digesta when the different protein-free diets were fed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Three bulls with an average live weight of 228 kg were fitted with ileo-caecal reentrant cannulas for the experiment. The rations were composed of 3 kg maize silage and 3 kg wheat straw pellets per animal and day. In a previous period 50% of the digesta was collected over 12 hours and stored deep-frozen. In the main period the digesta flow was interrupted for 30 hours. The digesta flow was collected quantitatively. In the caecal part of the re-entrant cannula previously collected digesta and starch (over 30 hours) as well as 15N urea (over 24 hours) were supplemented. The amount of starch corresponded to about 10% of the DM of the digesta. Analyses of the urine, faeces, ileum digesta and blood plasma were carried out. The quota of starch clearly stimulates bacterial processing in the large intestine so that 20.5% of the supplemented 15N was excreted in faeces within 24 hours. 91.2% of the 15N in the faeces was localised in the bacteria fraction. Individual differences of the animals distinctly show the connection between the excretion of the 15N in faeces and urine. A decreased isotope excretion in faeces of 17.2% for animal 3 in contrast to the 23% for animals 1 and 2 showed an increased elimination of the 15N through the kidney with 32.7% instead of 25.2%. The largest proportion of the ileum digesta, i.e. 46%, can be localised in the 15N urea fraction; the NH3-fraction is also distinctly labelled. With time progressing, the 15N quota flowing from the rumen to the small intestine increases.  相似文献   

6.
Fermentation pattern and yields of microbial protein were investigated in cultures of the rabbit caecal contents supplied with glucose, xylose, starch, pectin and xylan. Rabbits at the age of 4 weeks (before weaning) and 3 months were slaughtered, their caecal contents added at 1.1% to growth media and incubated anaerobically at 39 degrees C for 18 h. Caecal microorganisms of 4-week-old rabbits produced no methane and caproate, less butyrate, but more propionate than microorganisms of 3-month-old rabbits. In both groups of rabbits, fermentation of xylose produced significantly more propionate and less butyrate than fermentation of glucose. More propionate and less acetate was formed from starch than from pectin. In caecal cultures from 4-week-old rabbits with pectin, the molar percentages of acetate was significantly higher and percentages of other short-chain fatty acids (SCFA) lower than in cultures with starch or xylan. In cultures from 3-month-old rabbits, fermentation of pectin and xylan produced similar SCFA profiles, different from SCFA molar composition in cultures with starch. Average production of microbial protein was 129 mg per 1 g of carbohydrate digested (range 110 to 141 mg/g). Protein yields were the same on glucose and xylose, but nonsignificantly higher on starch than on pectin and xylan. It can be concluded that the characteristics of substrate affected fermentation pattern in mixed cultures of rabbit caecal microorganisms. Substrate effects on protein yields were not statistically significant, due to high variation.  相似文献   

7.
The objective of the present study was to evaluate the effects of dietary inulin and sucrose on the fermentation profile of the gastrointestinal microflora in chicken. Day-old broilers (n = 80) were assigned to four dietary treatments, either fed a basal diet or the same diet supplemented with sucrose (4%), inulin (1%) or sucrose and inulin. At day 35, birds were killed and pH, lactate, ammonia, short chain fatty acids (SCFA) and biogenic amines were determined in different parts of the digestive tract. Final body weights and the relative weights of liver, pancreas, crop, gizzard and small intestine were not influenced by treatment. The relative weights of the empty caeca and of the caecal digesta were higher with the diets containing inulin while caecal pH and ammonia were reduced. Lactate concentration was reduced in the crop (p < or = 0.01) and gizzard (p < or = 0.001) of sucrose-fed groups, while it was increased (p < or = 0.01) in the jejunum of inulin-fed group. Ammonia in the crop (p = 0.089) and gizzard (p = 0.067) tended to be lower in the group receiving inulin plus sucrose. Amongst SCFA, only acetate was detected in the crop and gizzard contents that tended to be lower (p = 0.09) in the crop digesta of sucrose plus inulin-fed group. N-butyrate (mol %) was higher (p < or = 0.001) in the caecal digesta of inulin-supplemented groups without affecting total SCFA. Dietary inulin elevated the concentration of putrescine in the jejunal and caecal contents. In the caecal digesta, total biogenic amines were increased (p < or = 0.001) in sucrose plus inulin-fed group without affecting production of biogenic amines in the jejunum. In conclusion, inulin could reduce the pH in the lower gastrointestinal tract of broilers, while sucrose had no acidifying influence in the upper digestive tract. Inulin enhanced the concentration or metabolic activity of butyrate-producing bacteria in the caecum. Further studies are needed to investigate the potential effect of inulin on the intestinal microbial composition.  相似文献   

8.
A 4-week experiment carried out on rats addressed the analysis of physiological properties of model casein diets supplemented with 5% cellulose or different preparations of chicory roots: flour, pulp, high- and low-molecular inulin (IN(HM) and IN(LM) respectively). Of all preparations, only pulp did not induce the hypertrophy of caecum walls or an increase in the bulk of caecal digesta. Chicory preparations lowered caecal pH and ammonia concentration (except IN(LM) preparation), evoked increased hydration of caecal digesta and protein content. The highest concentration of volatile fatty acids (VFA) was observed in rats fed a diet containing chicory pulp and IN(HM), whereas the lowest VFA concentration was reported after the administration of an IN(LM)-containing diet. The VFA pool was the highest in rats receiving a diet supplemented with chicory flour. All preparations examined diminished the coefficient of protein digestibility but not decrease nitrogen retention. The lowest levels of glucose and total cholesterol, at concurrently the highest level of HDL fraction, were recorded in serum of rats fed IN(LM). A distinct increase in intestinal wall and intestinal digesta, as well as the highest production of VFA and the lowest pH of caecal digesta indicate that chicory flour ingested to a semi-synthetic diet had the most profitable effect on the functioning of rat caecum, compared with other chicory products. Compared with the IN(HM), the preparation of IN(LM) increased caecal wall hypertrophy without increasing VFA production, still simultaneously increasing ammonia content and pH of caecal digesta, decreasing the total cholesterol concentration and increasing HDL content in serum.  相似文献   

9.
The experiment was carried out on 96 female broilers, allocated to eight groups of 12 birds kept in individual cages. Two basal wheat‐ and soyabean meal‐based diets containing 150 g/kg of rapeseed expeller cake were formulated, differing in the level of P: 7.1 g/kg in diet H or 5.9 g/kg in diet L. Rapeseed cake supplied 3.15 μmol alkenyl glucosinolates per gram of diet. The eight treatments were: basal diets only, basal diets + phytase (1000 U/kg), basal diets + organic acid blend (OA, 6 g/kg), or basal diets + both additives. Diets were fed from day 8 to 28 of life. The results showed that the lower dietary P content and OA supplementation did not significantly affect feed intake or BWG, while both increased (p < 0.001) after phytase supplementation. Tibia ash content as well as tibia ultimate strength were lower (p < 0.001) in birds fed diets L compared with diets H, and increased (p < 0.01) with phytase supplementation of diet L, while OA had no influence on either parameter. Dietary P levels and OA supplementation had no influence on the pH of gut digesta, but the pH of jejunal digesta increased following phytase supplementation (p < 0.01). Morphological measurements of the small intestinal mucosa of chicks indicated that OA added to diet L depressed villi height (p < 0.001) and crypt depth (p < 0.001); both parameters increased after phytase supplementation (p < 0.01). The lower total SCFA as well as acetic, propionic and butyric acid concentrations in caecal digesta indicated lower activity of caecal microflora in birds fed diets L compared with H. OA supplementation had no influence, while phytase supplementation increased the concentration of acetic acid in caecal digesta. Supplementation of diets with either phytase or OA increased thyroid weight by 16% (p < 0.01) and 11% (p < 0.05) respectively. The increase in thyroid weight because of phytase supplementation was greater at the lower dietary P level, and the greatest when both phytase and OA were added to the diet.  相似文献   

10.
Barrows with an average initial weight of 55 kg were fitted with simple T-cannulas at the distal ileum. The animals were fed a protein-free diet that consisted of 79.7% cornstarch, 10% sucrose, 3% Alphafloc (a source of cellulose), 3% canola oil and a vitamin-mineral premix. The pigs were fed 700 g of diet twice each day, at 0800 and 2000. A balanced amino acid mixture or a saline solution was administered intravenously while the protein-free diet was fed. Ileal digesta were collected for 24 h following a 7-d adaptation period. The administration of amino acids reduced (P less than .05) the recovery of endogenous protein from 18.5 to 12.7 g per kg dry matter intake. For the amino acids, the reduction was only significant (P less than .05) for proline, from 3.6 to .6 g per kg dry matter intake. If the total endogenous protein losses are assumed to be constant and the differences in the amino acid composition of non-reabsorbed endogenous protein, as observed in this study, are used to calculate true ileal digestibilities, differences in the digestibilities of the indispensable amino acids are large (up to 7.4 percentage units for threonine). The amino acid composition of endogenous protein determined in pigs fed a protein-free diet and parenterally administered with amino acids should provide a better estimate for the calculation of true amino acid digestibilities when based on the determination of true protein digestibility by the 15N-isotope dilution technique.  相似文献   

11.
1. The effect of caecal ligation and colostomy on water intake and excretion were examined in chickens fed a low-protein diet or a low-protein diet supplemented with urea. 2. When fed a low-protein diet, the water intake and the ratio of water intake to food intake were increased by colostomy (P < 0.05) but not changed further by caecal ligation of colostomised chickens. 3. When fed a low-protein diet supplemented with urea, the amount of water intake and the ratio of water intake to food intake were not changed by either treatment. 4. Total water excretion was much higher in the colostomised plus caeca-ligated chickens than in other 3 groups fed both types of diet (P < 0.05). 5. The amount of faecal water excretion was increased by cecal ligation in colostomised chickens fed either diet (P < 0.01). 6. No effect of any treatment on water balance was observed in chickens fed either diet. 7. It is concluded that the lower intestine plays a useful role in the water economy of chickens fed a low-protein diet or a low-protein diet supplemented with urea.  相似文献   

12.
Adult sows fed a constant amount of a basal diet received purified cellulose either orally at levels of 0 and 475 g/animal.d (Experiment 1) or intracecally at levels of 0, 285, 570 and 855 g/animal.d (Experiment 2). Each experiment consisted of subsequent periods of faeces and urine collection with the animals re-allocated to the treatments each time. With that, a total of 36 observations on each parameter was achieved. The faecal samples were analyzed for the contents of organic matter, cell wall carbohydrates and various nitrogen fractions such as bacterial N and undigested dietary N. Furthermore, N balance, urinary allantoin excretion and plasma urea concentrations were determined. In a preliminary study, the effects of freeze-drying and of shaking of the faecal samples as suspensions with water (in order to release bacteria from fibre) on content and composition of faecal nitrogen had turned out to be reproducible. Cellulose significantly enhanced faecal nitrogen loss whereas N retention was not affected due to the counteraction of urinary N loss. Plasma urea concentration reflected the situation with urinary N. The proportion of undigested dietary N and of water-soluble protein in total faecal N was somewhat increased by cellulose at cost of the bacterial N proportion which accounted for about 72% of total N on average. Urinary allantoin did not respond to the higher bacterial activity in the hindgut in the presence of supplementary cellulose. Cellulose significantly decreased the apparent N digestibility by on average about 3 percentage units per 100 g of supplementary cellulose. True N digestibility was also reduced by cellulose but did not go below 95%. The supplementary cellulose was fermented in the hindgut at similar rates of on average about 60% regardless of the route of administration. The almost 100 g of native cellulose incorporated in the basal diets were lignified by about 20%, and that is why they were fermented at a rate of only about 30%. The rate of fermentation was only slightly decreasing with increasing amounts of supplementary cellulose, and a daily quantity of 564 g (11 g/W0.75) cellulose was fermented on average if the highest level of cellulose was provided. This was within a range exclusively reported for easily-fermentable carbohydrates but was achieved in the case of cellulose only at a consistently higher level of supply. The true efficiency of bacterial protein synthesis was 5.2 g bacterial protein/100 g supplementary cellulose on average. The apparent efficiency was 60% higher averaging 8.4 g bacterial protein/100 g further apparently fermented organic matter.  相似文献   

13.
In a cross-over trial, five healthy dogs were fed a dry food without or with 1% (w/w) oligofructose to assess any oligofructose-induced effects on the faecal bacterial profile, nitrogen excretion and mineral absorption. The diets were given for a period of 3 weeks. Oligofructose feeding significantly raised the number of Bifidobacteria, Streptococci and Clostridia in faeces. The numbers of faecal anaerobic and aerobic bacteria were raised after ingestion of oligofructose. The faecal pH was unchanged. There was no effect of oligofructose feeding on the route of nitrogen excretion which was associated with a lack of effect on faecal ammonium and urinary urea excretion. It is suggested that the absence or presence of an effect of oligofructose on urinary and faecal nitrogen excretion depends on the background composition of the diet, in particular the content of non-digestible, fermentable carbohydrates. In the diets used, the content of non-digestible, fermentable carbohydrates was not measured. Both apparent magnesium and calcium absorption were significantly raised by oligofructose feeding, but phosphorus absorption was unaffected. The data presented may contribute to the qualification of the use of oligofructose in dog foods.  相似文献   

14.
Six pigs of initial weight 40 +/- 1.7 kg with a T-piece cannula fitted at the terminal ileum were given diets composed of 96.3% of rye, barley or triticum grains ground to pass the 2.6 mm mesh, 3.3% mineral and vitamin mixture and 0.4% Cr2O3. Each diet was given to all pigs in a Latin square design, and faeces and ileal digesta were collected on 7, 8, 9 and 10, 11 and 12 day of feeding each diet, respectively. The grains varied widely in the content of pentosans, polyuroids, beta-glucan and monosaccharides. The antitrypsin activities were 0.84, 2.73 and 1.62 TUI/g in barley, rye and triticum, respectively. Ileal and faecal apparent digestibilities of nitrogen and amino acids were higher (P less than or equal to 0.01) in Triticum than in barley and rye. The digestibility of carbohydrates (pentosans, beta-glucan, polyuroids and non-structural carbohydrates) were lower in pigs fed a rye diet than of those fed a Triticum diet. The results are discussed with respect of the role to non starch polysaccharides, especially pentosans in digestibility of nitrogen and energy in animals receiving a rye diet.  相似文献   

15.
The objective was to determine the effects of fermentable carbohydrates on phosphorus (P) metabolism, the chemical composition of the faecal mixed bacterial mass (MBM) and the microbial activity in the large intestine (LI) of pigs. Eight barrows (mean BW 35.9 ± 0.9 kg), fitted with simple T‐cannulas at the terminal ileum, were either fed a low‐P corn–soybean meal‐based control diet or 75% of the control diet supplemented with 25% cellulose, starch or pectin according to a 4 × 3 Latin Square design. Both pectin and cellulose caused higher faecal than ileal P recoveries. Ileal volatile fatty acids (VFA) levels were more pronounced for the starch (p < 0.05) rather than the cellulose and pectin treatments, whereas pectin resulted in a higher faecal VFA concentration in comparison to starch and cellulose (p < 0.05). The differences in faecal VFA concentrations corresponded to the pH values obtained in faeces. The N content of MBM was higher (p < 0.05) when cellulose was supplemented. Pectin caused a decrease in the P content of the MBM compared to the control (p < 0.05). As a result, the N:P ratio was significantly higher for the pectin (N:P = 4.33) than for the control treatment (N:P = 2.63), while the Ca:P ratio remained constant for all treatments, suggesting changes in the accumulation of N, P and Ca in MBM, probably due to changes in the species composition and activity of the microflora.  相似文献   

16.
The effect of different types of fibre on the intestinal digesta and microbial diversity was evaluated in growing pigs. The animals were fed during forty-two days with one of four experimental diets including a control group, a diet enriched with resistant starch type I, by coarse ground corn, and other two diets containing sugar beet pulp (8%) and wheat bran (10%) (as sources of soluble and insoluble non-starch polysaccharides respectively). Body weight (BW) and average daily feed intake (ADFI) were assessed at day 7, 21 and 42. Luminal samples of digesta from proximal colon were collected to analyse water retention capacity (WRC), concentration of short-chain fatty acids (SCFA) and the microbial diversity. Overall, animals fed with higher amounts of non-digestible carbohydrates had lower ADFI and BW. Sugar beet pulp provoked an increase of WRC, a higher concentration of SCFA, and a more stable microbial diversity throughout the experimental period. On the other hand, animals fed with wheat bran presented a lower bacterial diversity.  相似文献   

17.
为了评价棉子糖、水苏糖、果寡糖、甘露寡糖等4种非消化寡糖的发酵特性,以采食无抗生素日粮的肉仔鸡盲肠微生物为菌源,通过体外发酵试验比较短链脂肪酸(SCFA)的产量及产生速率。结果表明:棉子糖发酵6 h后,SCFA产量即迅速增加,显著高于其他发酵底物(P<0.05),而且在各发酵底物产生SCFA中乙酸比例最大、丁酸比例最小(P<0.05);24 h,SCFA产量达到最大,丁酸比例在各发酵组中也增至最大。水苏糖和果寡糖的发酵速率紧随棉子糖之后,但6 h和12 h的SCFA产量仅为棉子糖的一半左右,24 h的SCFA总产量分别达到棉子糖的83.81%和75.84%。甘露寡糖的发酵速率最慢,6、12、24 h的SCFA总产量仅为棉子糖的23.81%、18.90%、40.94%。  相似文献   

18.
Giant anteaters (Myrmecophaga tridactyla) are specialized insectivores and consume mainly ants and termites in the wild. In captivity, giant anteaters are either fed a complete diet, or a combination of a domestic carnivore diet with leaf eater pellets, or a traditional gruel‐type diet. Soft faeces are a frequently encountered problem with this type of feeding. In the present study, we analysed diet and faeces composition, calculated digestibility and measured mean retention time on various diets in eight giant anteaters (total of n = 64 experiments). The results suggest that the digestive physiology of giant anteaters is similar to that of domestic dogs and cats in terms of nutrient digestibility and digesta retention. When testing correlations between faecal dry matter content and other variables, no relationship with dietary crude fibre content or mean digesta retention time could be detected. However, acid insoluble ash intake was significantly and positively correlated with faecal dry matter content. The amount of acid insoluble ash excreted with the faeces was higher than that ingested with the diet offered, indicating that the giant anteaters ingested soil from their enclosure of up to 93 g per day. This finding is consistent with observation of faeces of wild giant anteaters that contain soil or sand most likely due to indiscriminate feeding. It also corresponds to reports that indigestible materials such as peat, soil, chitin or cellulose contribute to a firmer faecal consistency in various carnivore species. Therefore, offering giant anteaters the opportunity to voluntarily ingest soil from their enclosure might be beneficial.  相似文献   

19.
The objective of this study was to evaluate dietary galactooligosaccharide (Gal OS) addition on swine nutrient digestibility, ileal and fecal bacterial populations, and ileal short-chain fatty acid (SCFA) production, and to determine their impact on ileal fermentative characteristics in vitro. Twelve T-cannulated pigs (BW = 25 kg) were fed a diet free of Gal OS for 21 d. On d 22, ileal digesta samples were collected for an in vitro fermentation experiment (Exp. 1). Substrates included: raffinose/stachyose combination (R + S), soy solubles (SS), and transgalactooligosaccharides (TOS). Also included were the non-OS components of SS and TOS. Nine pigs (three donors per treatment) served as ileal effluent donors. Each substrate was fermented in vitro for 6 h, and pH and SCFA and gas production were determined. Pigs then were allotted to three treatments: a Gal OS-free control diet and the control diet with either 3.5% added Gal OS from SS or TOS. Diets, feces, and digesta samples collected weekly for 6 wk on d 6 (feces) and 7 (digesta) were analyzed for DM, OM, CP, and chromic oxide concentrations. Feces and ileal digesta were analyzed for bifidobacteria and lactobacilli populations. Ileal digesta samples were analyzed for SCFA. On d 64, a second in vitro fermentation experiment (Exp. 2) was conducted using ileal effluent from three pigs per treatment and the same substrates used in Exp. 1. In vivo results showed that ileal and total tract DM and OM digestion were decreased (P < 0.05) by addition of both SS and TOS to the diet. Ileal and total-tract N digestibilities were decreased (P < 0.05) by dietary addition of SS. Fecal bifidobacteria and lactobacilli were increased (P < 0.05) by addition of SS and TOS to the diet. Ileal propionate and butyrate concentrations were greater (P < 0.05) for pigs fed diets containing both sources of Gal OS. In vitro results showed that fermentation data were not affected by donor animal adaptation to treatment. For both in vitro experiments, gas and SCFA production were higher (P < 0.05) for R + S than for SS or TOS. Fermentation of R + S resulted in a higher pH (P < 0.05) than did SS or TOS. Fermentation of non-OS components of SS and TOS resulted in more (P < 0.05) gas and SCFA production, and pH values that did not differ (P > 0.05) compared to SS and TOS. The Gal OS used in this study were prebiotics, increasing beneficial bacteria in vivo and SCFA concentrations both in vivo and in vitro.  相似文献   

20.
Two experiments were performed on sheep, receiving on maintenance level a pelleted straw ration high in crude fibre (straw, 70.5%; dried sugar beet pulp, 12%; cereals, 10%; urea, 2%; ammonium hydrogen carbonate, 3%; minerals 2,5%). The animals were fitted with ileo-caecal re-entrant cannulas. The effects of the introduction of HC1-partly hydrolysed straw meal into the digesta of the large intestine on the digestion processes in that segment were studied. Under these conditions the metabolism of 14C and 15N labelled urea, which was given into the caecum, was estimated. In experiment 1 (E 1; 2 animals) unlabelled, precollected digesta were hourly reintroduced together with 14C and 15N labelled urea via the caecal cannula. In experiment 2 (E 2; 3 animals) the digesta were supplemented with partly hydrolysed straw meal (10% of the mean daily DM-intake with the ration). The supplement of partly hydrolysed straw meal caused an increase of the 15N excretion with faeces from 13.4% (E 1) to 19.8% (E 2) of the dose. The 15N was mainly incorporated in the bacterial fraction (98% E 1; 96% E 2). As a reason for the increased 15N incorporation into the bacterial fraction of 106.4 mg15N' in E 2 vs. 67.3 mg15N' in the experiment without straw meal supplement the higher supply of energy as fermentable carbohydrates was assumed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号