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PubMed2003

Effects of stage of maturity on ensiling characteristics and ruminal nutrient degradability of oat silage.

A study was conducted to determine the effects of stage of maturity on ensiling characteristics and ruminal nutrient degradability of oat silage. Oat was field grown and forage was harvested at the boot or soft dough stage and ensiled in mini-silos for 0, 2, 4, 8, 16 and 45 days. Two lactating Holstein cows fitted with ruminal fistulas were used determine ruminal nutrient degradability. Regardless of the stage of maturity, ensiled forages went through a rapid fermentation with a sharp decline in pH during the first 2 days of ensiling. Extensive proteolysis took place between 0 and 2 days as indicated by a reduction in true protein and neutral detergent insoluble protein (NDICP) and an increase in non-protein nitrogen (NPN). Chemical analysis of the 45 days silage showed that stage of maturity had no effect on neutral detergent fibre (NDF) and acid detergent fibre (ADF) of oat silage. However, oat harvested at the boot stage contained more crude protein (CP) and less starch than that harvested at the soft dough stage. Distribution of protein fractions showed that oat harvested at the boot stage contained lower NPN, NDICP and acid detergent insoluble protein than oat harvested at the soft dough stage. Results of the in situ incubation experiment indicated that oat harvested at the soft dough stage had lower ruminal dry matter (60.6 vs. 66.4%). CP (81.3 vs. 88.7%) and NDF (35.4 vs. 42.2%) degradabilities than oat harvested at the boot stage. It was concluded that chemical composition and ruminal nutrient degradability of oat silage are significantly influenced by stage of maturity.

Animal Feed↗
PubMed2001

Effect of harvest date and variety on ruminal degradability of ensiled maize grains in dairy cows.

In this study we investigated the influence of harvest date and genotype on the ruminal degradability of the organic matter of ensiled maize grains. Grains of the varieties Avenir, Byzance, CGS 5104 and CGS 5107 from six different harvest dates were available; they are classified as intermediate types between flint and dent corn. The six harvest dates, during which time the dry matter content of the ensiled grains rose from 52% to 66%, extended from 1st September to 19th October. Assuming a passage rate of k = 0.08, the effective ruminal degradability declined in this period on average from 93% to just under 79%; variety-specific deviations also increased markedly during this period. The dry matter content (x, DM in %) of the ensiled grains had a profound influence on ruminal degradation: a highly significant curvilinear decline in ruminal degradability (y) was calculated at increasing DM levels (k = 0.08), which can be described by the equation y = -0.072x2 (+/- 0.010) + 7.417x (+/- 1.186) - 98.71 (+/- 34.58) (B = 0.96; sy.x[%] = 1.36). The ruminal degradability of ensiled maize grains is about 5-10% higher than that of fresh maize grains.

Animal Nutritional Physiological Phenomena↗
PubMed2006

Effects of tea saponins on in vitro ruminal fermentation and growth performance in growing Boer goat.

Two experiments were conducted to investigate the effects of tea saponins (TS) on in vitro ruminal fermentation and growth performance in growing Boer goats. In Experiment 1, the Reading Pressure Technique (RPT) system was used to investigate the effect of addition of TS (0, 0.2, 0.4 and 0.8 mg/ml) on the ruminal fermentation in vitro. The 24h gas production and methane emission were significantly decreased when 0.4 or 0.8mg TS was included, suggesting that the TS could inhibit the release of methane. Compared to the control, the TS had little effect on pH values and the concentration of total volatile fatty acids in the ruminal fluids. However, the fermentation patterns were changed, with lower acetate and higher proportions of propionate when TS was added. Ammonia-N concentration and protozoal counts were significantly reduced, while microbial protein yield was increased by the TS addition, suggesting that the TS could modify the ruminal fermentation. In Experiment 2, 27 growing Boer goats were used to evaluate the effects of the TS addition on growth performance. The animals received the same basal diets, and added TS at levels of 0 (C), 3 g (T1) and 6 g (T2) per day. The experiment lasted for 60 days with the first 15 days for adaptation. Blood samples were obtained by jugular venipuncture before the morning feeding on the final day of the experiment. During the whole periods, dry matter intake, average daily gain and feed efficiency in T1 were higher than in the other two. Serum total protein, albumin, high density lipoprotein cholesterol, Ca and P and alkaline phosphatase levels were higher in group T1 than in C and T2, whereas the blood urea nitrogen, creatinine and total cholesterol were lower in the TS-added groups. The concentrations of glucose, glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase were not affected by the TS. From the results obtained in this study, it is inferred that the TS could modify the ruminal fermentation and that proper doses of TS may have potential in improving the animal growth performance, whereas at high doses, it may have adverse effects on animal production.

Animals↗
PubMed1977

[Isobutylidene-di-urea as a new NPN source for ruminants. 2. Metabolism of 14C-15N-isobutylidene-di-urea in sheep].

2 male sheep (weighing 45 kg and 44 kg) were fitted with a ruminal fistula and a jugular vein catheter and received isobutylidendi-urea for a 42-day period of adjustment. The diet contained 25% starch, 23.8% glucose, 29.0% cellulose, 10.0% straw, 1.7% sunflower seed oil, 4.3% isobutylidendi-urea, 5.6% minerals and vitamins. Each animal received 60 g of isobutylidendi-urea in daily amounts of 1.4 kg of the ration-4.4% of the total dietary N came from the straw. At the begin of the trial each sheep received 30 g of 14C15N isobutylidendi-urea (C1-siobutyl labelling) administered as a suspension. The animals were then placedin respiration cages. The peak of specific 14C activity in the expired air (including ruminal gas) was observed 2 hrs after the beginning of the trial. 18--30 hrs after the beginning of the trial the highest level of 15N incorporation into the TCE (trichloroacetic acid) soluble fraction of the ruminal fluid was noted resulting from the reflow of urea via the rumeno-hepatic circulatory system in the rumen. A high concentration of 15N was shown to be present, for prolonged period, in the TCE soluble fraction of the ruminal fluid (up to the 30 hr of experiment). The 15N concentration in the blood plasma (TCE soluble portion) was found to increase reaching a peak value 23 hrs after administration of the isotope. The highest level of 14C activity in this fraction appeared 1 hr after isotope administration. The 15N incorporation into the protein fraction of blood plasma reached a constant high level between the 29th and 47th hr of experiment. The highest 15N concentrations in urine were noted after 1 day. 3.5% of the administered dose of 14C activity and 23% of the supplied amount of N were excreted in the urine. 20% of the total amount of 15N excreted in the urine could be detected as 14C isobutyl residues. An excess of between 0.05 and 0.17 atom% of the isotopes were found in muscular tissue and in different organs of the sheep when these were slaughtered on the 7th day of experiment (liver: 0.17%, kidneys: 0.14%, muscle: 0.05%, heart: 0.08%). The results obtained in the present trial clearly indicate that ruminants are able to utilize nitrogen from isobutyldi-urea.

Animal Feed↗
PubMed1989

Ruminal degradability of crude protein from different treated soybean meals in lactating cows.

Ruminal crude protein (CP) degradability of four commercially available soybean meal (SBM) types--untoasted (U), toasted (T), heat-treated (H) and formaldehyde-treated (F)--was studied by the use of in sacco and in vivo techniques with lactating German Friesian cows cannulated in the rumen, duodenum and ileum. In two in sacco experiments three cows were fed a diet based either on grass hay plus ear-maize silage or on barley whole plant silage. Ruminal degradation rate of CP was estimated as percent nitrogen (N) disappearance from polyester bags incubated in the rumen for 2, 4, 6, 8, 12 and 24 h. Ruminal degradation rate of CP varied among the four SBM types as well as between the two basal diets. N disappearance from the bags after 12 h of incubation averaged 96, 67, 37, and 23% for the U, T, H, and F SBM types, respectively, in the cows fed the hay/ear-maize silage diet vs 99, 86, 58 and 41% for the four SBM types, respectively, in the cows fed the barley whole plant silage diet. In the in vivo experiment, four cows were fed diets based on meadow hay and ear-maize silage in a 4 x 4 Latin square design. The effect of SBM treatment on the flow rate of non-ammonia N (NAN) into the duodenum, and its relationship with the ruminal degradation rate of CP of the four SBM types, was studied. Formaldehyde treatment increased the amount of NAN entering the duodenum (P less than .05): 485 g cow-1 day-1 compared to 383, 418 and 428 g for U, T and H, respectively. Calculated ruminal CP degradabilities were 93, 75, 71 and 38% for SBM types U, T, H and F, respectively.

Animal Feed↗
PubMed1977

The public health significance of fat-modified ruminant foods.

The apparent consumption of dietary fat in Australia is 115 g/person/day, of which two-thirds is contributed by ruminant-derived foods. Consequently, the polyunsaturated fatty acid/saturated fatty acid ratio of the Australian diet is low, approximately 0.2. Recently a process has been developed which allows modification of the fatty acid composition of ruminant body fat, and a range of foodstuffs (fat-modified foods) which have a substantially higher polyunsaturated fatty acid/saturated fatty acid ratio than their conventional counterparts has been produced and marketed. In the clinical trials in which there was complete substitution of fat-modified ruminant foods for conventional ruminant products the fall in serum cholesterol was approximately 10%. In the trial in which there was only partial substitution the fall in serum cholesterol was insignificant. Using the equation developed by Keys, the predicted fall in serum cholesterol resulting from varying degrees of substitution of fat-modified ruminant meats for their conventional counterparts in the Australian diet is shown to be negligible. The fat-modified products were marketed at approximately twice the price of their conventional counterparts and it is claimed that this will limit the degree of substitution. It is concluded that the public health significance of fat-modified foods is limited.

Animal Feed↗
PubMed1992

Regulation of pancreatic exocrine secretion in ruminants: a review.

Mechanisms regulating ruminant pancreatic exocrine function differ in some respects from those in nonruminants. This may affect the post-ruminal digestion of certain dietary nutrients such as starch. Ruminants do not exhibit clearly defined cephalic and gastric phases of pancreatic regulation, a likely consequence of the continuous nature of digesta flow from the rumen. Local neural reflexes and secretin-mediated exocrine responses may be more important than stimulation by cholecystokinin. Additionally, the ruminant pancreas may be stimulated by short-chain fatty acids produced in the rumen. A "ruminal phase" of pancreatic exocrine regulation has been proposed. The failure of cattle to digest efficiently starch in the small intestine may result from an asynchrony between delivery of starch to the intestines and pancreatic amylase release.

Animals↗
PubMed2002

Glucose uptake via SGLT-1 is stimulated by beta(2)-adrenoceptors in the ruminal epithelium of sheep.

Glucose absorption via the sodium glucose-linked transporter (SGLT)-1, decreases the glucose concentration in the ruminant forestomach and may ameliorate or prevent ruminal lactic acidosis. Because acidotic ruminants show increased sympathetic activity, the possibility of adrenergic modulation of SGLT-1 was investigated. Glucose uptake into ovine ruminal epithelia was measured in Ussing chambers after the addition of 200 micromol/L (14)C-labeled glucose to the mucosal solution. Glucose uptake decreased (P < 0.05) by >50% in comparison with control after mucosal addition of the SGLT-1 inhibitor, phlorizin (100 micromol/L). Serosal preincubation with 100 micromol/L epinephrine increased (P < 0.05) the phlorizin-sensitive glucose uptake in the absence and presence of indomethacin (10 micromol/L). The effect of epinephrine was simulated by beta- (100 micromol/L isoproterenol) and beta(2)-receptor agonists (10 micromol/L terbutaline), as well as by direct stimulation of adenylyl cyclase (10 micromol/L forskolin). The serosal addition of methoxamine, clonidine, dobutamine or BRL 37344 had no effect. Inhibition of protein kinase A with 2 micromol/L H 89 completely abolished the stimulation of glucose uptake by epinephrine. We conclude that ruminal SGLT-1 can be stimulated via beta(2)-dependent generation of cyclic adenosine monophosphate.

Acidosis, Lactic↗
PubMedDate not supplied

The role of angry rumination and distraction in blood pressure recovery from emotional arousal.

OBJECTIVE: Cardiovascular recovery of prestress baseline blood pressure has been implicated as a possible additional determinant of sustained blood pressure elevation. We hypothesize that angry ruminations may slow the recovery process. METHOD: A within-subjects design was used in which resting baseline blood pressure and heart rate measurements were assessed on 60 subjects, who then took part in two anger-recall tasks. After each task, subjects sat quietly and alone during a 12-minute recovery period randomized to with or without distractions. During baseline, task, and recovery, blood pressure was continuously monitored; during recovery, subjects reported their thoughts at five fixed intervals. RESULTS: Fewer angry thoughts were reported in the distraction condition (17%) compared with no distraction (31%; p = .002); an interaction showed that this effect was largely the result of the two intervals immediately after the anger-recall task. Trait rumination interacted with distraction condition such that high ruminators in the no-distraction condition evidenced the poorest blood pressure recovery, assessed as area under the curve (p = .044 [systolic blood pressure] and p = .046 [diastolic pressure]). CONCLUSIONS: People who have a tendency to ruminate about past anger-provoking events may be at greater risk for target organ damage as a result of sustained blood pressure elevations; the effect is exacerbated when distractions are not available to interrupt the ruminative process.

Anger↗
PubMed1987

Depression of reticulo-ruminal motor functions through the stimulation of alpha 2-adrenoceptors.

Inhibition of the cyclical contractions of the reticulum and the rumen by detomidine (10-40 micrograms/kg, i.v.), xylazine (20-80 micrograms/kg, i.v.) and clonidine (2.5-10 micrograms/kg, i.v.) were compared in sheep and cattle housed individually in box stalls. Two alpha 2-adrenergic receptor blocking agents, tolazoline and yohimbine, were administered intravenously for prevention (0.1-0.4 mg/kg) or reversal (0.4-1.2 mg/kg) of these effects. Continuous recording of the reticuloruminal contractions and measurement of the volume of ruminal gas eliminated through the upper respiratory tract indicated that the three alpha 2-agonists inhibited the primary ruminal contractions associated with the reticular contractions. The occurrence of secondary ruminal contractions was also blocked in sheep, but only suppressed in cattle. The inhibition of reticulo-ruminal contractions was prevented or reversed competitively by the two alpha 2-blocking agents, suggesting an alpha 2-adrenoceptor mediation of the inhibition of cyclical motor activity of the reticulo-rumen. In contrast with tolazoline, yohimbine was unable to alleviate the accumulation of gas resulting from inhibition of the secondary ruminal contractions.

Adrenergic alpha-Agonists↗
PubMed1988

Inhibition of rumination in sheep by alpha-adrenoreceptor antagonists.

Rumination activity was recorded in sheep during a period of 3 h. The amount of rumination occurring in 30 min following the intravenous injection of an alpha 1 blocking drug (prazosin, 0.1 mg/kg) and an alpha 2 blocking drug (idazoxan, 0.1 mg/kg) was reduced compared with control days when saline was given. The observation that rumination can be stimulated by a rapid, intravenous dose of adrenalin was confirmed. The induction of rumination by adrenalin was prevented by these alpha-adrenoreceptor antagonists given singly or together at the dose rate mentioned. These findings are discussed in the light of knowledge that normal reticulo-ruminal motility and food intake can be inhibited by stimulation of alpha 2-adrenoreceptors.

Adrenergic alpha-Antagonists↗
PubMed1989

The adrenergic receptors in the control of reticulo-ruminal myoelectrical activity in sheep.

The involvement of adrenoreceptors in the control of reticulo-ruminal (R-R) motility was electromyographically studied in five conscious adult ewes. Intravenous (i.v.) administration of the beta 2-agonist ritodrine (10 or 20 micrograms/kg.min for 15 min) or alpha 1-blocker prazosin (20 micrograms/kg.min for 30 min) or the beta 1- and beta-blocker acebutolol and propranolol, respectively, (30 micrograms/kg.min for 30 min) had no significant effect on R-R phasic myoelectrical grouped discharges (PMGD). Administration of the alpha 1-agonist phenylephrine (4 micrograms/kg.min i.v. for 15 min) significantly increased for 25 min both the frequency of R-R PMGD and the percentage of occurrence of secondary ruminal PMGD and provoked rumination. Pretreatment of animals with prazosin prevented these R-R responses to phenylephrine. Administration of the alpha 2-agonist naphazoline (2.5 micrograms/kg.min i.v. for 15 min) stopped the reticular PMGD for 1 hour, after an initial increase in their frequency, and greatly decreased the frequency of ruminal PMGD. When animals were pretreated with the alpha 2-blocker yohimbine (20 micrograms/kg.min i.v. for 30 min), naphazoline failed to produce any effect on R-R PMGD. Yohimbine, given either alone or followed by naphazoline, abolished secondary ruminal PMGD for about 2 hours. The beta 1-agonist (+)-dobutamine (30 micrograms/kg.min i.v. for 15 min) provoked a pause in R-R PMGD, which reappeared soon after the end of drug administration. Pretreatment of ewes with acebutolol or propranolol prevented dobutamine from producing its effects on R-R PMGD.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

The effects of intracoeliac injections of alpha-adrenergic agonists and veratridine on reticuloruminal motility and the evocation of rumination in sheep.

The ability of alpha-2 adrenoreceptor agonists and veratridine to evoke rumination and to modify reticular motility in adult Suffolk-cross sheep when injected by close-arterial injection into the forestomach was investigated. The specific alpha-2 adrenoreceptor agonists, xylazine and medetomidine, evoked rumination and increased reticular motility. The Na+ channel activator veratridine also evoked rumination and dramatically increased reticular motility. In contrast, injection of the alpha-1 adrenoreceptor agonist, phenylephrine, was ineffectual in evoking rumination and resulted in reduced reticular motility. It is concluded that the evocation of rumination by alpha-2 adrenergic agonists and veratridine is probably due to the activation of sensory nervous receptors (epithelial receptors) located in the reticulorumen.

Adrenergic alpha-Agonists↗
PubMed2006

Factors affecting lysine degradation by ruminal fusobacteria.

Fusobacterium necrophorum can readily be enriched from the rumen with lysine, and its deamination rate is very rapid. The addition of F. necrophorum JB2 to mixed ruminal bacteria significantly increased lysine degradation, but only if the ratio of ruminal fluid to basal medium was less than 25%. If more ruminal fluid (pH 6.1) was added, ammonia production decreased by as much as 80%. Clarified, autoclaved ruminal fluid was also inhibitory. When F. necrophorum JB2 was grown in a lysine-limited continuous culture (0.1 h(-1) dilution rate) and pH was decreased using HCl, optical density decreased linearly, and the culture washed out at pH 5.6. Batch cultures of F. necrophorum JB2 deaminated as much lysine at pH 6.1 as at pH 6.6, but only if fermentation acids were not present. Sodium acetate (100 mM) had little effect at pH 6.6, but the same concentration inhibited ammonia production by 80% at pH 6.1. The idea that fermentation acids could prevent the enrichment of fusobacteria in vivo was supported by the observation that dietary lysine supplementation did not enhance the lysine deamination rate of the mixed ruminal bacteria.

Ammonia↗
PubMed1984

Control of intrinsic reticulo-ruminal motility in the vagotomized sheep.

The intrinsic motility of the reticulo-rumen was studied by electromyography in nineteen sheep subjected to bilateral thoracic vagotomy and maintained by intragastric infusion of a complete liquid diet. The influences of distension, temperature and tactile and chemical stimuli on the intrinsic reticulo-ruminal motility were investigated. The level of electrical discharge in the reticulum and rumen in the first 3 days after vagotomy was increased progressively with distension without giving rise to the large group discharges characteristic of the long-term vagotomized sheep, and was reduced by atropine (0.1-1 mg kg-1) but not by hexamethonium (2 mg kg-1). In the long-term vagotomized animals, the frequency of the large group discharges over the reticulo-rumen varied with the degree of reticulo-ruminal distension. The discharges were absent below a threshold rumen volume; above the threshold they increased progressively with volume until a maximal rate of six to seven regular discharges per minute was established at large ruminal volumes. The discharges were abolished by atropine (0.1-1 mg kg-1) or hexamethonium (2 mg kg-1). With the rumen volume below the threshold, in all areas of the reticulo-rumen localized distension stimulated local discharge only and did not induce large group discharge. Replacement of rumen contents with an equal volume of 0.2 M-acetic, -propionic or -butyric acid buffered to pH 4.0 rapidly abolished the large group discharges over the entire reticulo-rumen. Replacement of rumen contents by an equal volume of 0.9% NaCl at 30 degrees C immediately abolished the large group discharges; at temperatures between 35 and 43 degrees C this had no effect. Gentle tactile stimulation increased local discharge in the reticulum and cranial dorsal sac but not in other areas of the rumen and did not affect large group discharge in any region. It is concluded that the intrinsic reticulo-ruminal motility of chronically vagotomized sheep is principally regulated by the degree of reticulo-ruminal distension. Like the C.N.S.-controlled motility of the vagus-intact sheep it is inhibited by high concentrations of volatile fatty acids. Local control mechanisms therefore may interact with central control in the over-all regulation of motility in vagus-intact sheep.

Animals↗
PubMed1977

Weight increase of cotton fibers during swelling in alkali as a sensitive measure of cellulose degradation in ruminal fluid.

Weight increase of cotton fiber in an 18% NaOH solution, termed "alkali-centrifuge" or "AC" value, was measured after incubation of either 1 g or 100 mg of the fiber in ruminal fluid. The AC response was a sensitive measure of cellulolytic activity. Thus, fiber incubated at 21 and 51 degrees C exhibited major AC increases even when direct weight losses of the unswollen fiber were less than 2%. Similarly, progressive additions of acetic acid to ruminal fluid progressively depressed both AC response and direct weight loss, but the former was still easily measurable when the latter was not. In tightly closed, completely filled vials with high ratio of ruminal fluid to sample, AC increased greatly and rapidly, i.e., in 6 h. This time could be further reduced to 2 h by overnight "preincubation" of the ruminal fluid with cotton fiber before starting the test incubation. Certain surfactants used to aid wetting of the fiber had a low but measurable potency in inhibiting cellulose digestion, but other surfactants were non-inhibitory. The AC response was maintained when ruminal fluid was diluted with an equal amount of McDougall's "artificial saliva" solution.

Journal Article↗
PubMed1988

Sensitivity of ruminal microorganisms to pentachlorophenol.

Pentachlorophenol (PCP) is used extensively as a biocidal agent, and there is considerable concern about the adverse effects of this compound in biological ecosystems. The effects of PCP on the growth and fermentative activity of cultures of mixed ruminal microorganisms and the sensitivity of 14 ruminal bacterial species to PCP in pure culture were examined in this study. Increasing concentrations of PCP (9.4 to 375.4 microM) depressed growth and propionate concentrations in cultures of mixed ruminal microorganisms. Wide differences in the sensitivities of ruminal bacterial strains to various concentrations of PCP were observed. Cellulolytic strains were highly sensitive to PCP, while amylolytic, sugar-utilizing, and intermediate acid-utilizing strains were more resistant. Growth of major succinate-producing strains was depressed by PCP. Strains which depend on substrate level phosphorylation appeared to be more resistant. The data suggest that the adverse effects of PCP on ruminal microorganisms may be the result of its role as both an uncoupler of electron transport and a protonophore.

Animals↗
PubMed1988

Enrichment and isolation of a ruminal bacterium with a very high specific activity of ammonia production.

When mixed ruminal bacteria were inoculated into semicontinuous cultures (25% transfer every other day) containing lactate, dulcitol, pectin, or xylose and Trypticase (1 g/liter) as the sole nitrogen source, the specific activity of ammonia production increased. The greatest enrichment was observed with lactate and xylose, and in these cases the specific rate of ammonia production was eightfold higher than that of the ruminal fluid control (approximately 35 nmol of ammonia per mg of protein per min). Isolates with different morphologies were obtained from each of the enrichments, but in no case did the specific activity of any isolate exceed that of the mixed ruminal bacteria. If Trypticase (15 g/liter) was used as the only energy and nitrogen source, there was an even greater increase in ammonia production, and two monensin-sensitive bacteria, a Peptostreptococcus species and a Clostridium species, were obtained. The Peptostreptococcus species was unable to grow on any of 25 carbohydrate or carbohydrate derivatives tested; but the Clostridium species was able to use glucose, maltose, fructose, cellobiose, trehalose, sorbitol, and salicin as energy sources. Neither organism was able to grow in the absence of an amino acid source, but growth rates on Trypticase were greater than 0.35/h. The specific activities of ammonia production were 346 and 427 nmol/mg of protein per min for strains of Peptostreptococcus and Clostridium, respectively. Megasphaera elsdenii and Bacteroides ruminicola, previously isolated ruminal ammonia producers, had specific activities of only 11 and 19 nmol of ammonia per mg of protein per min, respectively. The most probable number of Clostridium species in ruminal fluid was less than 10(3)/ml, but the Peptostreptococcus species was present at 10(8)/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Ammonia↗