Microbial metabolism in the forestomachs and the large intertine of sheep

1965 ◽  
Vol 16 (1) ◽  
pp. 77 ◽  
Author(s):  
VJ Williams

Sheep were fed on either lucerne chaff, high wheat grain, or high maize grain rations. Analyses were made on digesta from the rumen and large intestines of cannulated and slaughtered animals. The results for the large intestine showed that, when equal quantities of dry matter are given, the composition of the ration can affect the pH, the water content, and the total dry matter of the digesta; diet can also affect the total quantities of volatile fatty acid and ammonia in the organ.The proportions of the individual volatile fatty acids in the caecal fluid were not affected by the different diets fed in this experiment. The data did not suggest any consistent pattern in the pH or in the concentrations of ammonia and volatile fatty acid in the caecal fluid during the 24 hr between feeds.

1968 ◽  
Vol 21 (1) ◽  
pp. 89 ◽  
Author(s):  
VJ Williams ◽  
TR Hutchings ◽  
KA Archer

Ten acute experiments were performed on sheep to study the relative rates of absorption of volatile fatty acids in acid solution from the reticulo-rumen and abomasum. When the solutions in the two organs were approximately the same in initial tonicity, pH, and volatile fatty acid concentration, the total volatile fatty acid was absorbed at about equal rates from both the reticulo-rumen and the abomasum. The individual volatile fatty acids were absorbed from the abomasum at different rates; the rate was faster the greater the number of carbon atoms in the molecule. Ammonia in acid solution was not absorbed from the reticulo-rumen or from the abomasum.


1967 ◽  
Vol 18 (4) ◽  
pp. 625 ◽  
Author(s):  
FV Gray ◽  
RA Weller ◽  
AF Pilgrim ◽  
GB Jones

l(a). Volatile fatty acid (VFA) production (moles/12 hr) by two sheep fed at 2-hourly intervals on a constant ration containing equal parts of wheaten hay and lucerne hay, showed no significant difference between the sheep or between day-time and night-time values. The precision with which production could be measured over a series of 12-hr periods is given. The quantities of VFA produced in the rumen on successive days varied considerably; the extent of this variation was similar to that occurring in the quantities of faeces passed. (b) Production remained much the same whether the sheep were fed at intervals of 1, 2, or 12 hr. (c) The energy of the VFA produced in the rumen was equivalent to about 54% of the digestible energy of the diet. 2. Similar amounts of VFA were produced from two different mixtures of wheaten hay and lucerne hay, and from lucerne hay alone. 3. A modification in the procedure for measuring VFA production was tested and found to be satisfactory. The necessary apparatus could be readily carried on the back of a freely moving sheep.


1973 ◽  
Vol 136 (2) ◽  
pp. 311-319 ◽  
Author(s):  
R. Ash ◽  
G. D. Baird

1. The total capacities of homogenates of bovine liver and rumen epithelium to activate acetate, propionate and butyrate were determined. 2. Activating capacities were assayed by measuring the rate of formation of the corresponding CoA esters. The methods used for determining the concentrations of the CoA esters allowed the CoA esters of acetate, propionate and butyrate to be distinguished. It was thus possible to investigate the effect of the presence of a second volatile fatty acid on the rate at which a given volatile fatty acid was activated. 3. The propionate-activating capacity in rumen epithelium was decreased by about 87% in the presence of butyrate, the acetate-activating capacity in liver was decreased by about 55% in the presence of either propionate or butyrate, and the butyrate-activating capacity in liver was decreased by about 40–50% in the presence of propionate. 4. All three activating capacities in liver appeared to be located in the mitochondrial matrix and membrane. The three activating capacities had similar locations to each other in rumen epithelium as well, although in this case activity was more evenly divided between the mitochondria and the cytoplasm. 5. The relative activating capacities towards the volatile fatty acids in the two tissues, together with the ability of one volatile fatty acid to inhibit the activation of another volatile fatty acid, appear to ensure that butyrate is mainly metabolized in the rumen epithelium and that propionate is metabolized in the liver.


1957 ◽  
Vol 49 (2) ◽  
pp. 180-183 ◽  
Author(s):  
A. John ◽  
G. Barnett ◽  
R. L. Reid

1. The findings presented in two previous papers on the yields of volatile fatty acids, obtained by the action of rumen liquor in the artificial rumen, from fresh grass, dried grass and the water-soluble and water-insoluble separates of the latter, have been amplified by a consideration of the acids similarly obtained from specimens of chemically prepared crude fibre and cellulose, from four of the dried grass specimens.2. The proportions of different volatile fatty acids from grass crude fibre and grass cellulose resemble those obtained from cellulose powder, propionic acid being produced in greatest relative yield.3. A general review of these latter findings, in relation to those already presented, has been given.


RSC Advances ◽  
2015 ◽  
Vol 5 (62) ◽  
pp. 50033-50039 ◽  
Author(s):  
Xue Yang ◽  
Lei Wen ◽  
Xiang Liu ◽  
Si Chen ◽  
Yayi Wang ◽  
...  

Although many pretreatment methods are employed to enhance the hydrolysis of waste activated sludge (WAS), the bioconversion of soluble complex substrates needs improvement to produce higher volatile fatty acids (VFAs).


1976 ◽  
Vol 35 (3) ◽  
pp. 365-371 ◽  
Author(s):  
D. S. Parker ◽  
R. T. Mcmillan

1. A method of obtaining dialysed samples from the caecum of the conscious rabbit is described.2. Values for total volatile fatty acid content and for molar proportions of individual volatile fatty acids in dialysate samples were in good agreement with those obtained from caecal material.3. The volatile fatty acid level in the caecum throughout the day was determined using two groups of animals, one group fed ad lib. and the other group on a restricted food intake. These results indicated a marked diurnal fluctuation in volatile fatty acid level in the caecum of rabbits fed once/d which was not evident in those fed ad lib.


1968 ◽  
Vol 22 (2) ◽  
pp. 261-280 ◽  
Author(s):  
J. H. Topps ◽  
R. N. B. Kay ◽  
E. D. Goodall

1. The flow of digesta to the abomasum and through the duodenum and terminal ileum was measured over 24 h periods in sheep. Pelleted diets of concentrates, principally composed of barley, and of poor-quality hay were given. The seven Scottish Blackface ewes studied were all fitted with rumen cannulas, and in addition two had simple abomasal cannulas, one a re-entrant abomasal cannula, two re-entrant duodenal cannulas, and two re-entrant ileal cannulas.2. Paper impregnated with chromium sesquioxide was given twice daily by rumen fistula. The amounts of dry matter, starch, cellulose, total nitrogen and energy passing through the abomasum, duodenum and ileum and the amounts excreted in the faeces were measured. The flows of digesta were adjusted to give 100% recovery of chromium sesquioxide and the extent of digestion in various parts of the alimentary tract was calculated using these adjusted values. Concentrations of glucose in the blood and of volatile fatty acids (VFA) in the rumen were also measured.3. For the concentrate diet, 69% of the digestible dry matter disappeared in the stomach (reticulo-rumen, omasum and abomasum), 17% in the smail intestine and 14% in the large intestine. Values for disappearance of digestible energy were 72% in the stomach, 23% in the small intestine and 5% in the large intestine. Of the 298 g starch fed daily only 6–35 g passed through the abomasum or duodenum and only 1–4 g reached the terminal ileum. The cellulose in the diet was poorly digested.4. For the hay diet, 67% of the digestible dry matter disappeared in the stomach, 22% in the small intestine and 11% in the large intestine. Values for disappearance of digestible energy were 81% in the stomach, 7% in the small intestine and 12% in the large intestine. Of the 33 g of starch consumed daily, from 5 to 13 g passed through the abomasum or duodenum. The cellulose in the hay was 59% digestible and virtually all this digestion took place in the stomach.5. The concentration of VFA and the proportion of propionate in the rumen fluid, 2·5 h after feeding, were considerably greater on the concentrate diet than on the hay diet, but diet had little influence on the concentration of blood glucose.6. The importance of the small amount of starch passing to the sheep's small intestine is discussed.


2019 ◽  
Vol 14 (1) ◽  
pp. 8-17
Author(s):  
João Chrysostomo de Resende ◽  
João Luiz Pratti Daniel ◽  
André Rodrigues da Cunha Barreto-Vianna ◽  
Juliano Vogas Peixoto ◽  
Gregório Correia Guimarães ◽  
...  

Cannulated cows were allocated to a cross-over design to evaluate the technique for determination of volatile fatty acid (VFA) clearance by infusion of marker solution into intact ruminal digesta, and verify the technique sensibility to the variation in the diet. Animals received diet of forage or forage plus concentrate and infusion of valeric acid and Cr-EDTA solution into intact or evacuated ruminal digesta. The total fractional rate of VFA clearance (FRVFAC) was estimated by the exponential decay of valerate over time. The passage FRVFAC to the omasum was assumed as the decay in ruminal Cr concentration and the absorption FRVFAC was estimated by the difference. The total FRVFAC and absorption did not differ between techniques. The passage FRVFAC, however, was lower when the marker solution was added into the evacuated digesta, probably reflecting the destabilization of the rumen environment during the evacuation and the largest volume of fluid observed in animals with evacuated digesta. In conclusion, the infusion of marker solution into intact digesta with homogenization performed by ruminal motility could be usable for the VFA ruminal clearance determination since it seems to cause lesser disturbance in the ruminal environment.


2020 ◽  
Vol 8 (2) ◽  
pp. 66
Author(s):  
Aulia Rahman ◽  
Sunarso Sunarso ◽  
B.I.M. Tampoebolon ◽  
L.K. Nuswantara

Penelitian ini bertujuan untuk mengkaji pengaruh aras starter pada fermentasi sabut kelapa terhadap Kecernaan Bahan Kering (KcBK), Kecernaan Bahan Organik (KcBO) dan Volatile Fatty Acids (VFA) dengan metode in vitro. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL). Percobaan terdiri dari 4 perlakuan aras starter yaitu T0 (fermentasi sabut kelapa + 0% starter), T1 (fermentasi sabut kelapa + 2% starter), T2 (fermentasi sabut kelapa + 4% starter), dan T3 (fermentasi sabut kelapa + 6% starter) dengan 5 ulangan tiap perlakuan dan lama fermentasi 10 hari. Hasil penelitian menunjukkan sabut kelapa yang difermentasi dengan aras starter sampai 6% dapat meningkatkan (P<0,05) KcBK dan KcBO tetapi berpengaruh tidak nyata pada VFA. Rata-rata nilai KcBK dan KcBO pada perlakuan T0, T1, T2 dan T3 berturut-turut adalah KcBK 28,08%; 30,71%; 34,27%; 35,78% dan KcBO 28,73%; 31,81%; 35,21%; 36,88%. Rata-rata nilai produksi VFA pada perlakuan T0, T1, T2 dan T3 berturut-turut adalah 130 mM, 125 mM, 118 mM dan 120 mM. Simpulan penelitian adalah pemberian aras starter mampu meningkatkan KcBK dan KcBO dan produksi VFA memiliki kecenderungan menurun serta pemberian aras starter optimal pada level 4%. Kata kunci : Fermentasi, In vitro, Kecernaan, Sabut kelapa, Volatile fatty acid.


1977 ◽  
Vol 28 (6) ◽  
pp. 1075 ◽  
Author(s):  
GJ Lee

Changes in the composition of digesta along the gastrointestinal tract of scouring sheep fed on wheat grain ad libitum were studied relative to sheep fed on lucerne hay ad libitum. Wheat engorgement significantly (P < 0.005) depressed the pH of the digesta in the reticulorumen and the digestive tract distal to the jejunum. A mean total volatile fatty acids concentration of 10.3mM in the caecum of scouring sheep was significantly lower than the mean of 51.6mM in sheep fed on lucerne hay. Net absorption of water was negligible in the colon of scouring sheep as digesta were only 13.7–14.7% dry matter, whereas in sheep fed on lucerne, the dry matter of digesta increased from 14.7% in the caecum to 27.9% at the rectum.


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