Effect of defaunation and refaunation of the rumen on cellulolytic activity in vitro with or without ammonia supplementation

1991 ◽  
Vol 71 (3) ◽  
pp. 913-917 ◽  
Author(s):  
K. Ushida ◽  
Y. Kojima

The effect of defaunation and refaunation of the rumen on cellulose digestion in vitro was examined with special reference to ammonia supply. Digestion of cellulose by DF and RF rumen populations was measured using a simple in vitro batch system with or without ammonia supplementation. Ammonia was supplied to the cultures either as ammonium sulfate or ammonium chloride solution. Cellulose digestion was increased by the presence of either protozoa or ammonia. The protozoal effect was evident in the absence of ammonia supplementation and the ammonia effect was evident in the absence of protozoa. The form of the ammonia supplement did not affect cellulose digestibility. Key words: Protozoa, ammonia, cellulose digestion

2012 ◽  
Author(s):  
Zalilah Sharer Sahir ◽  
John Malcolm Sykes

Degradasi pada besi bersalut cat dari segi gelembung yang terbentuk telah dikaji selepas direndam di dalam larutan 3% natrium klorida dan 3% ammonium klorida. Imbasan probe Kelvin (SKP) telah digunakan untuk menghasilkan peta keupayaan kimia–elektro bagi mengenal pasti kawasan anod dan katod dibawah gelembung dan kawasan persekitarannya. Bagi gelembung yang terhasil pada panel yang direndam dalam larutan 3% sodium klorida, peta upaya SKP menunjukkan gelembung yang terbentuk adalah di kawasan katod yang disebabkan oleh alkali, dimana kawasan anod juga dilihat terbentuk berdekatan. Walhal bagi peta upaya SKP untuk gelembung yang terhasil pada panel yang direndam di dalam larutan 3% ammonium klorida menunjukkan kehadiran kawasan katod dikelilingi oleh kawasan anod. Kata kunci: Cat organik; imbasan probe Kelvin; gelembung The degradation of a coated metal in term of the area underneath a blister has been studied after being immersed in 3% sodium chlorida and 3% ammonium chloride solution. Scanning Kelvin probe (SKP) was used to map electrochemical potentials, identifying anodic and cathodic regions underneath a blister and the surrounding coating. For blisters formed on coated panel immersed in sodium chlorida solution, SKP potential map reveals that the blister has formed at a cathode due to alkali but anodes form nearby (not remote). Meanwhile SKP potential map for blister formed on coated panel in 3% ammonium chloride reveals the presence of cathodic regions within the anodic areas. Key words: Organic coating; scanning Kelvin Probe; blister


1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.


1956 ◽  
Vol 15 (4) ◽  
pp. 1180-1187 ◽  
Author(s):  
C. N. Huhtanen ◽  
R.F. Elliott

1972 ◽  
Vol 78 (3) ◽  
pp. 457-464 ◽  
Author(s):  
R. J. Wilkins

SUMMARYPotential cellulose digestibility, measured by incubation in vitrofor 6 days, decreased during floral development in perennial ryegrass, Wimmera ryegrass, cocksfoot, oat and tall fescue. The rate of decline was slower than for cellulose digestibility measured after incubation in vitro for 2 days only. Morphological fractions ranked in order of descending potential cellulose digestibility – leaf blade, inflorescence, leaf sheath and stem.Lignin content was determined chemically by the method of Van Soest (1963) and lignified tissue was assessed by staining transverse sections of leaf blades and leaf sheaths with safranin and fast green. Both lignin and lignified tissue increased with maturity. Lignified tissue increased mainly through increase in the number of scleren-chyma cells, but was also affected by the formation of lacunae or cavities between the vascular bundles in leaf blades of cocksfoot and in leaf sheaths of all species studied. For 19 samples of leaf blades and leaf sheaths, potential cellulose digestibility had significant negative correlations with both lignin content (r = -0·862) and lignified tissue (r = -0·905). Limitations to the techniques used to assess lignification and further factors which may affect the relationship between lignification and potential cellulose digestibility are discussed.


1982 ◽  
Vol 62 (3) ◽  
pp. 751-757 ◽  
Author(s):  
J. A. BASARAB ◽  
R. T. BERG ◽  
J. R. THOMPSON

The in vitro glucose consumption and lactic acid production by erythrocytes from 20 cattle of a Beef Synthetic (SY) breed group and 25 cattle of a double-muscled (DM) breed group were determined. There were three age groups and two sexes within each breed group. Animals within the DM breed group were categorized as either phenotypically normal- to moderate-muscled (DM carriers) or extreme-muscled (extreme DM) based on the phenotypic expression of the double-muscling trait and on their breeding history. Both DM phenotypes had higher (P < 0.01) erythrocyte glucose consumption and lactic acid production than normal-muscled, noncarrier cattle of the SY breed group. Extreme DM cattle were not different (P > 0.05) in either their erythrocyte glucose consumption or lactic acid production compared with DM carriers. No difference (P > 0.05) due to breed or phenotype was observed in the molar ratio of lactic acid produced to glucose consumed by erythrocytes. These results suggest that carriers of the Double Muscled Syndrome, regardless of phenotypic expression of the double-muscling trait, have a higher rate of erythrocyte glycolysis than normal cattle. Key words: Cattle, double muscled, erythrocyte, glucose, lactic acid


1995 ◽  
Vol 34 (2) ◽  
pp. 85-88 ◽  
Author(s):  
Taeko ITOH ◽  
Hiroshi YAMADA ◽  
Akihiko YAMAGUCHI ◽  
Nakaaki KAWAMATA ◽  
Masafumi KAKEI ◽  
...  

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