Caecal Metabolism Research Articles

Increasing dietary crude protein levels attenuates the effects of caecotrope deprivation in growing rabbits

The effect of caecotrope deprivation on growth, caecal metabolism and Volatile Fatty acid (VFA) production was studied in rabbits fed varying levels of dietary protein during a 42-days feeding trial. Fourty-eight mixed breed rabbits (average initial weight = 875±25 g) were divided into two groups viz; caecotrope consuming (CC) and caecotrope-deprived (CD) groups. Rabbits in the 2 groups were divided equally and assigned to 3 diets containing different crude protein (CP) levels (12, 15 and 18%) in a 2 × 3 factorial arrangement. The result revealed that increasing dietary CP improved (P<0.05) the proximate composition of the caecotrope. The live weight, weight gain, feed conversion ratio, nitrogen utilization and VFA production in CD rabbits fed diets containing 18% CP were comparable (P<0.05) with those of CC fed diets with 15% CP. Nitrogen utilization increased (P<0.05) following increasing dietary crude protein level. Molar proportions of acetate, butyrate, and propionate were higher (P<0.05) in CC rabbit compared to CD. Lactobaccilus acidophilus was isolated from the caecum of CC rabbits. It was concluded that caecotrope deprivation has detrimental effect on growth, nitrogen metabolism, VFA production and caecal bacteria and this effect can be attenuated by increasing the dietary protein level in growing rabbits.

Effects of dietary addition of Macleaya cordata alkaloid extract on growth performance, caecal indices and breast meat fatty acids profile in male broilers

The aim of this experiment was to investigate whether a low-dietary application (15 mg/kg) of an alkaloid preparation containing quaternary benzo[c]phenanthridine alkaloids and obtained from Macleaya cordata (Sangrovit) influenced caecal metabolism, growth performance and long-chain fatty acid composition of breast meat. One-day-old broiler chicks (Cobb 500) were fed a diet without supplement or with a 15 mg/kg dose of Sangrovit (C and A groups respectively) for 5 weeks. Although the A treatment was not accompanied by an enhanced final body weight of broilers, the intake of a diet with Sangrovit influenced the caecal microflora activity. The addition of Sangrovit to a diet decreased potentially harmful β-glucuronidase and β-glucosidase activities (p<0.05 and p=0.075 respectively), and at the same time led to a significant increase in activities of bacterial glycolytic enzymes α-glucosidase, α-galactosidase, β-galactosidase in comparison to the control group. The concentration of total short-chain fatty acids in the caecal digesta was increased in the A treatment contributing to the tendency towards lower caecal pH (p=0.078). The analysis of breast meat fatty acids showed that the dietary application of Sangrovit evoked some changes in contents of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) contents. The applied dosage of Sangrovit caused an increase in the sum of MUFA and the tendency towards lower PUFA sum (p<0.05 and p=0.062 respectively) as in relation with the C group. Although the nutritionally relevant n-6/n-3 PUFA and the (PUFA+MUFA)/saturated fatty acids ratios remained similar in both groups, further research is postulated to establish the effect of this preparation on meat quality. To sum up, despite of a lack of the improvement in final body weight, a low dose of dietary Sangrovit was found to exert positive effects on the caecal metabolism of the broilers.

ORIGINAL ARTICLE: Application of soybean meal, soy protein concentrate and isolate differing in α-galactosides content to low- and high-fibre diets in growing turkeys

The aim of this experiment was to investigate the physiological and growth response of young turkeys (up to 8 weeks of age) to dietary replacement of soybean meal (SBM) by soy protein concentrate (PC) or protein isolate (PI). This replacement resulted in a differentiated dietary concentration of α-galactosides of over 2.5% in the SBM diet, approximately 2% with a mixture SBM and PC, 1% with a PC diet and 0.1% with a PI diet. Each treatment was applied in two ways: with lower (3.5%) or higher (5.3%) dietary crude fibre content, made by supplementation with soybean hulls. The highest and lowest body weight of turkeys was recorded both after the first and second 4-week half of the study in the PC and PI-type diets respectively. A gradual withdrawal of α-galactosides from a diet was accompanied by a decline in ileal tissue mass, ileal viscosity and activity of endogenous maltase (the latter was found to be significant at 4 weeks of age). At the same time, two-way anova revealed that an elevated level of crude fibre (HF treatment) caused an increase in ileal tissue mass (p < 0.05 after 4 weeks of feeding) as well as a decrease in activity level of intestinal sucrase and maltase. The presence of raffinose family oligosaccharides in a diet, in contrast to dietary crude fibre level, significantly affected the caecal metabolism. The rate of bacterial production of short-chain fatty acids in the caeca was distinctly diminished by dietary withdrawal of α-galactosides. In conclusion, the soy protein concentrate, in contrast to the protein isolate preparation, exerted positive effects on the turkeys' growth and gastrointestinal tract physiology and should be considered as an effective SBM substitute.

Gastrointestinal tract metabolism of young turkeys fed diets supplemented with pure nystose or a fructooligosaccharide mixture

In a four-week experiment on 60 7-day-old BUT-9 male turkeys the effects of dietary fructooligosaccharides (pure nystose and a fructooligosaccharide mixture) supplemented at 1 and 2%, were studied on ileal and caecal metabolism. The control carbohydrate was cellulose, added also at 1 or 2%. Each dietary treatment consists of 10 birds kept individually. The average degree of polymerisation of the nystose and oligofructose preparation amounted to 2.9 and 4.1, respectively. The addition of nystose significantly decreased the pH value and viscosity in the ileal contents compared with the cellulose treatment. On the other hand, the oligofructose preparation increased the activity of sucrase and lactase in the ileal mucosal by 30–60% and 33–47%, respectively. Both fructan preparations similarly acidified the caecal and colonic digesta (by 0.2–0.4 pH units) as well as diminished the activity of bacterial harmful β-glucuronidase (by 24–40%), but only nystose caused an enlargement of the caeca and effectively reduced caecal ammonia concentration, especially at a higher dose. Oligofructose supplementation at 2% caused a 3.5-fold increase of bacterial activity of α- and β-galactosidase, while 2% nystose resulted in 1.7 and 3 times higher α- and β-glucosidases activities, respectively. Compared to oligofructose, dietary nystose increased propionic and decreased butyric fermentation in caeca. Nystose and oligofructose preparations added at 2% reduced the triacylglycerol concentration in the serum in comparison to the addition of 2% cellulose by 46 and 25%, respectively. Beside the fact that dietary levels of supplementation were of great importance, the results indicated that even small difference in the length of carbohydrate chain may cause different physiological responses.

Effect of a starter diet supplementation with mannan-oligosaccharide or inulin on health status, caecal metabolism, digestibility of nutrients and growth of early weaned rabbits

The effect of a dietary supplementation with mannan-oligosaccharide (MOS, Bio-Mos, Alltech Inc.) and inulin (Frutafit® IQ) on growth, health, and caecal traits was studied on 348 rabbits (Hyplus®), weaned at 25 days of age. Three hundred and thirty rabbits (110 per group) were used for the health status and growth performance trial, while 18 rabbits (six per group) were used for caecal metabolism evaluation at the age of 42 days of age. Three diets were formulated: C (control), M (0.3% MOS) and I diet (4% inulin). Digestibility of the diets was measured in 10 rabbits per group between 36 and 40 days of age. The control diet was fed to rabbits of the C group from weaning to 74 days of age (slaughter). Diets M and I were fed to rabbits of the respective group from weaning to 46 days of age, then were fed with control diet till slaughter. From 25 to 46 days of age, the weight gain was slightly higher in control rabbits ( P = 0.11), while no differences were recorded for the whole period. No differences among groups in the mortality, which was high due to an enteropathy-infected environment, were significant. The lowest morbidity ( P = 0.05) as well as the health risk index were recorded in rabbits fed the diet with inulin ( P = 0.03). After change of diet, the health risk index increased in the rabbits previously fed the diet with additives, thereby no significant differences in the health status were recorded for the whole period. Total caecal volatile fatty acids concentration was higher ( P < 0.01) and the pH ( P < 0.01) and ammonia concentration ( P = 0.01) lower in rabbits fed the inulin diet than in other rabbits. In these animals, acetate molar proportion was higher ( P = 0.01) and that of propionate as well as the propionate/butyrate ratio significantly lower than in other rabbits. Butyrate molar proportion was higher in rabbits fed the diet with MOS ( P < 0.01). In rabbits fed the inulin diet a higher activity of inulinase was recorded ( P < 0.001) than in other rabbits. A significantly lower digestibility of cellulose was observed in rabbits fed the diet with MOS. The results of our study suggest the importance of using inulin-type fructans in the nutrition of young rabbits. The higher health risk index of rabbits after change of diets indicates that prebiotics should be given for a longer time during the fattening period.

Growth performance and metabolic response of the gastrointestinal tract of turkeys to diets with different levels of mannan-oligosaccharide

In four studies, we evaluated the influence of dietary MOS on the performance of turkeys and their intestinal health status at various stages of the production. Turkey growth, feed efficiency and large intestine parameters were examined after 4-, 8- and 16-week administration of diets with different levels (0.1 to 1.0%) of a MOS. The experimental 4- and 8-week feeding with various levels of MOS (up to 0.5%) did not affect the productivity of the birds, yet medium (0.4 and 0.2% in the first and second 8-wk periods, respectively) and high (1.0 and 0.4% in the first and second 8-wk periods, respectively) levels of dietary MOS were found to significantly increase live body weight after feeding for 16 weeks. At the age of 8 weeks, we observed a similar effect of MOS and inulin on the productivity parameters. The caecal metabolism was affected by dietary mannan variously depending on the dose of MOS and the age of birds. Generally, the dietary mannan-oligosaccharides more considerably changed caecal metabolism at early ages. At 4 weeks of age, we found some positive effects of adding MOS to the diet, such as lowering ammonia concentration and decreasing β-glucuronidase activity in the caeca, as well as some negative effects, including decreased bacterial glycolytic activity and raised pH of digesta. In our 8-week experiment, non-linear changes were observed in the parameters of caecal digesta at different doses of MOS. It seems that dietary supplementation with 0.25% MOS, compared to other doses, exerted a specific effect on gut-colonizing microflora enhancing its proliferation and activity, which has been reflected in a higher concentration of Lowry's protein and an increased glycolytic activity. After feeding the turkeys for 16 weeks, their caecal metabolism was affected by dietary MOS to some extent. Although MOS did not change the caecal pH or the bacterial enzyme activity, when applied at medium and higher doses it decreased ammonia as well as SCFA concentration (mainly acetate) in the caecal digesta. Dietary MOS had no significant effect on the caecal populations of Bifidobacterium and Lactobacillus, whereas the populations of caecal E. coli were observed to decrease, especially upon medium and high experimental concentrations.

Growth performance and metabolic response of the gastrointestinal tract of turkeys to diets with different levels of mannan-oligosaccharide

In four studies, we evaluated the influence of dietary MOS on the performance of turkeys and their intestinal health status at various stages of the production. Turkey growth, feed efficiency and large intestine parameters were examined after 4-, 8- and 16-week administration of diets with different levels (0.1 to 1.0%) of a MOS. The experimental 4- and 8-week feeding with various levels of MOS (up to 0.5%) did not affect the productivity of the birds, yet medium (0.4 and 0.2% in the first and second 8-wk periods, respectively) and high (1.0 and 0.4% in the first and second 8-wk periods, respectively) levels of dietary MOS were found to significantly increase live body weight after feeding for 16 weeks. At the age of 8 weeks, we observed a similar effect of MOS and inulin on the productivity parameters. The caecal metabolism was affected by dietary mannan variously depending on the dose of MOS and the age of birds. Generally, the dietary mannan-oligosaccharides more considerably changed caecal metabolism at early ages. At 4 weeks of age, we found some positive effects of adding MOS to the diet, such as lowering ammonia concentration and decreasing β-glucuronidase activity in the caeca, as well as some negative effects, including decreased bacterial glycolytic activity and raised pH of digesta. In our 8-week experiment, non-linear changes were observed in the parameters of caecal digesta at different doses of MOS. It seems that dietary supplementation with 0.25% MOS, compared to other doses, exerted a specific effect on gut-colonizing microflora enhancing its proliferation and activity, which has been reflected in a higher concentration of Lowry's protein and an increased glycolytic activity. After feeding the turkeys for 16 weeks, their caecal metabolism was affected by dietary MOS to some extent. Although MOS did not change the caecal pH or the bacterial enzyme activity, when applied at medium and higher doses it decreased ammonia as well as SCFA concentration (mainly acetate) in the caecal digesta. Dietary MOS had no significant effect on the caecal populations of Bifidobacterium and Lactobacillus, whereas the populations of caecal E. coli were observed to decrease, especially upon medium and high experimental concentrations.

Nutritional properties of tubers of conventionally bred and transgenic lines of potato resistant to necrotic strain of Potato virus Y (PVYN).

The potential effect of genetic modification on nutritional properties of potatoes transformed to improve resistance to a necrotic strain of Potato virus Y was determined in a rat experiment. Autoclaved tubers from four transgenic lines were included to a diet in the amount of 40% and compared with the conventional cv. Irga. The experiment lasted 3 weeks and special attention was paid to nutritional properties of diets, caecal metabolism and serum indices. Genetic modification of potato had no negative effect on the chemical composition and nutritional properties of tubers, ecosystem of the caecum, activity of serum enzymes and non-specific defence mechanism of the rats. Obtained results indicate that transgenic potato with improved resistance to PVY(N): line R1F (truncated gene coding for PVY(N) polymerase in sense orientation), R2P (truncated gene coding for PVY(N) polymerase in antisense orientation), and NTR1.16 (non-translated regions of PVY(N) genome in sense orientation) are substantial and nutritional equivalence to the non-transgenic cultivar. Tubers of transgenic line NTR2.27 (non-translated regions of PVY(N) genome in antisense orientation) increased the bulk of caecal digesta and the production of SCFA as compared to tubers of the conventional cultivar and the other transgenic clones. Taking into account some deviations, it seems reasonable to undertake a long-term feeding study to confirm the nutritional properties of tubers of transgenic lines.

Biological response of rat fed diets with high tuber content of conventionally bred and transgenic potato resistant to necrotic strain of potato virus (PVY N). Part II. Caecal metabolism, serum enzymes and indices of non-specific defence of rats

The potential effect of genetic modification on nutritional properties of potatoes was determined in a rat experiment. The potato cultivar Irga was transformed with viral genome sequences in order to improve its resistance to a necrotic strain of potato virus Y (PVY N). Four clones of genetically-modified potato were compared with the conventional variety Irga and non-transgenic somaclone from cv. Irga. Autoclaved and dried potato tubers were introduced in a high amount (40%) to rat diets. The genetic status of the potato had no effect on the mass of the caecum and caecal digesta. The parameters tested were pH, dry matter content and bacterial enzyme activity, comprising α- and β-glucosidase, α- and β-galactosidase, and β-glucuronidase. The results indicate that improvement of potato resistance to PVY N by genetic transformation had no negative effect on the ecosystem of the caecum of the rats, activity of serum enzymes (aspartate and alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase and creatine kinase) and non-specific defence mechanisms (lysozyme and ceruloplasmine level, number of bacteria taken up per cell and the percentage of the phagocytic cells in the serum).

Effect of low and moderate fibre levels on the caecal metabolism of young growing rabbits

Investigations with 15N'-labelled urea were carried out to find out the influence of the amount of fibre on the reflux of 15N' into the caecum to take part in the caecal metabolism. Two pelleted diets, containing 9.7% (group 1 with 23% oat hulls) and 2.2% (Group 2 without oat hulls) crude fibre, with urea with 60 atom% 15N-excess (15N) used as marker were given to three White New Zealand rabbits each group. Group 1 and 2 consumed 109 and 72 g fresh matter per rabbit and day, respectively. Daily 15N'-intake per rabbit was 307 mg in group 1 and 279 mg in group 2. Most of 15N' was eliminated directly via the urine. The daily faecal excretion in group 1 and 2 was 5.3 and 2.3 mg 15N', respectively. Only about 20 to 30% of 15N' and volatile fatty acids in the caecum and higher amounts of 15N' in muscles were found. The animals of this group consumed nearly the total amount of faeces by caecotrophy. Therefore 24 g of group 2 was still satisfying compared to 33 g live weight gain/rabbit and day of group 1. It is concluded that the animals of group 2 could compensate the low fibre level within a period of about 20 days by a more efficient utilization, the consumption of crude protein and starch being 18 and 12% lower than in group 1, respectively. Feed intake and health status were not evidently affected. The results are in contradiction to the common knowledge.

The effects of ispaghula on rat caecal fermentation and stool output

The colonic fermentation of ispaghula, a mucilage from Plantago ovata composed mainly of arabinoxylans, and its effects on stool output and caecal metabolism were investigated. Four groups of eight rats were fed on a basal diet (45 g non-starch polysaccharides/kg) for 28 d. The diet was then supplemented with ispaghula (g/kg; 0, 5, 15 or 50) for 28 d. Ispaghula increased stool dry weight and apparent wet weight but faecal water-holding capacity (amount of water held per g dry faecal material at 0.2 mPa) was unchanged. The extent of faecal drying in the metabolism cages was measured for rats fed on the basal diet and 50 g ispaghula/kg diet. At the faecal output levels encountered, only an 8% loss of wet weight would be predicted over 24 h and this was independent of diet. Faecal short-chain fatty acid (SCFA) concentration did not change but SCFA output increased. The molar proportion of SCFA as propionic acid increased and faecal pH was reduced. Values from pooled faecal samples suggested that approximately 50% of the ingested ispaghula was excreted by the 50 g ispaghula/kg diet group. Diaminopimelic acid (a constituent of bacterial cells) concentrations fell but output was unchanged indicating no change in bacterial mass. Similar changes were seen in the caecal contents but caecal pH and SCFA were unaffected. Ispaghula increased both caecal and colonic tissue wet weight and colonic length. Our results suggest that ispaghula is partly fermented in the rat caecum and colon, and loses its water-holding capacity. However, it is still an effective stool bulker and acts mainly by increasing faecal water by some unknown mechanism.

Dietary modification of potential vitamin K supply from enteric bacterial menaquinones in rats

Rats given a low-fibre diet based on boiled white rice developed symptoms of severe vitamin K deficiency within 23 d. Inclusion of autoclaved black-eye beans (Vigna unguiculata) in the diet prevented the bleeding syndrome. To test the hypothesis that deficiency resulted from low phylloquinone intake exacerbated by inadequate production of menaquinones by the enteric bacteria, a follow-up experiment was carried out in which groups of rats were given an all-rice diet, a rice + beans diet or a stock diet. Rats on the all-rice diet had significantly lower faecal concentrations of the main menaquinone-producing bacterial species (Bacteroides fragilis and Bacteroides vulgatus) than animals on either of the other two diets. This coupled with the much lower faecal output on this diet suggests that total menaquinone production was low for the all-rice diet. The alterations in faecal flora were associated with several significant changes in caecal metabolism. Rats given the stock diet had much shorter caecal transit times and a considerably greater proportion of butyric acid in volatile fatty acid end-products than did rats on either of the other two diets.

The influence of dietary fibre on caecal metabolism in the rat.

The influence of three diets ((1) high-fibre - low-fat, (2) low-fibre - high-fat, (3) commercial breeding diet) on the concentration of short chain fatty acids (SCFA) has been investigated in male and female rats up to 14 weeks of age. Hydrogen was detected in respired gas in all rats with no significant differences between diets or sex. Methane was detected only in control-fed rats at 12 weeks of age and thereafter. Caecal contents contained higher concentrations of SCFA than were found in faeces. There were no significant differences in the total faecal SCFA excreted by rats on the three diets. The proportions of SCFA in the caecum and faeces were influenced by diet. The production and excretion of hydrogen, methane and SCFA in the rat appeared to reflect different aspects of bacterial metabolism. Comparison of caecal and faecal SCFA may indicate differential absorption from the colon or differential metabolism by bacteria or colonic mucosa which may be influenced by diet.

Carbon monoxide and methane production in rats, guinea pigs, and germ-free rats.

ArticleCarbon monoxide and methane production in rats, guinea pigs, and germ-free rats.F L Rodkey, H A Collison, and J D O'NealF L Rodkey, H A Collison, and J D O'NealPublished Online:01 Aug 1972https://doi.org/10.1152/jappl.1972.33.2.256MoreSectionsPDF (1 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByRole of Carbon Monoxide in Host–Gut Microbiome Communication22 October 2020 | Chemical Reviews, Vol. 120, No. 24Gnotobiotics and the MicrobiomeReport on the Relative Affinity Constant (M) of Hemoglobin for Carbon Monoxide in the Animal World: A Comparative Review with a Meta-Analysis Based on a Systematic Review16 December 2019 | Journal of Evolutionary Biochemistry and Physiology, Vol. 55, No. 5Non-invasive continuous real-time in vivo analysis of microbial hydrogen production shows adaptation to fermentable carbohydrates in mice18 October 2018 | Scientific Reports, Vol. 8, No. 1Preliminary Studies Demonstrating Acetoclastic Methanogenesis in a Rat Colonic Ring ModelJournal of Nutrition and Metabolism, Vol. 2013Methane output of rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus) fed a hay-only diet: Implications for the scaling of methane production with body mass in non-ruminant mammalian herbivoresComparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, Vol. 158, No. 1Role of hydrogen and methane breath testing in gastrointestinal diseasesDigestive and Liver Disease Supplements, Vol. 3, No. 2GnotobioticsA rebreathing method for measuring lung volume, diffusing capacity and cardiac output in conscious small animalsRespiratory Physiology & Neurobiology, Vol. 146, No. 2-3Chemistry and Biology of Heme Effect of Metal Salts, Organometals, and Metalloporphyrins on Heme Synthesis and Catabolism, with Special Reference to Clinical Implications and Interactions with Cytochrome P-45022 September 2008 | Drug Metabolism Reviews, Vol. 25, No. 1-2Increase in colonic methanogens and total anaerobes in aging ratsApplied and Environmental Microbiology, Vol. 55, No. 10Fermentation of wheat bran and gum arabic in rats fed on an elemental diet9 March 2007 | British Journal of Nutrition, Vol. 60, No. 2An experimental design to study colonic fibre fermentation in the rat: the duration of feeding9 March 2007 | British Journal of Nutrition, Vol. 55, No. 3The influence of dietary fibre on caecal metabolism in the rat24 July 2007 | British Journal of Nutrition, Vol. 50, No. 3A sensitive analytical apparatus for measuring hydrogen production rates. I. Application to studies in small animals. Evidence of the effects of an α-glucosidehydrolase inhibitor in the ratAnalytical Biochemistry, Vol. 119, No. 2The variability of dietary fibre in laboratory animal diets and its relevance to the control of experimental conditionsFood and Cosmetics Toxicology, Vol. 18, No. 6Biological oxidation of [14C]methylene chloride to carbon monoxide and carbon dioxide by the ratToxicology and Applied Pharmacology, Vol. 40, No. 1Effect of dihalogenated methanes on the in vivo production of carbon monoxide and methane by ratsToxicology and Applied Pharmacology, Vol. 40, No. 1PhysiologyCarbon Monoxide Production as a Measurement of Heme CatabolismFolic acid abnormalities in iron deficiency: the mechanism of decreased serum folate levels in ratsThe American Journal of Clinical Nutrition, Vol. 27, No. 4 More from this issue > Volume 33Issue 2August 1972Pages 256-60 https://doi.org/10.1152/jappl.1972.33.2.256PubMed4559941History Published online 1 August 1972 Published in print 1 August 1972 Metrics

Factors affecting the transport of volatile fatty acids across rumen epithelium.

Factors affecting the transport of volatile fatty acids across rumen epithelium.