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PubMed1985

Rumination syndrome in children treated by increased holding.

Rumination syndrome--the frequent regurgitation of previously ingested food into the mouth where it is chewed--is a common, life-threatening disorder of retarded individuals. Four cases are described in which holding a retarded, ruminating child for 10-15 min before, during, and after meals, was associated with remission of rumination. Simple holding was effective in three; in the fourth, it was necessary to punish the child by putting her into a separate room for 3 min immediately after regurgitation. A within-subject reversal experimental design suggested that holding and not simple distraction was the effective component of the treatment. Treatment benefits were well maintained when the child returned to a home environment in which he or she continued to be held periodically. It is proposed that there are two behavioral etiologies for idiopathic rumination syndrome--social deprivation and reward learning through increased attention for regurgitation. Holding is the treatment of choice for the first type, and punishment with time out may be necessary to suppress regurgitation in the second type.

Child Behavior Disorders↗
PubMed2006

Negative bias in the perception of others' facial emotional expressions in major depression: the role of depressive rumination.

Depressed individuals display a negative bias in the perception of others' facial emotional expressions. The extent of this selective processing, moreover, has proven predictive of a poor outcome in depression. However, to date, little is known about the possible mechanisms that may account for this bias. This study examined the hypothesis that rumination--an analytical type of self-focused attention--would be associated with higher levels of perception of negative facial emotions in major depression. Twenty-six depressed patients (17 women) completed the Perception of Facial Expressions Questionnaire, the Ruminative Response Scale, and other measures assessing depression-related constructs. Consistent with prediction, rumination was positively related to a negative bias in the judgment of facial expressions, even when controlling for other depression-related variables. Although the correlational design of the present study limits the extent to which conclusions can be drawn on the directionality of the observed relationship, the present study reveals self-focused rumination as a possibly important causal mechanism in explaining depressed persons' negative bias in the perception of others' facial emotions.

Adult↗
PubMedDate not supplied

The role of rumination in recovery from reactivity: cardiovascular consequences of emotional states.

OBJECTIVE: While most investigations of the link between blood pressure responses and later disease have focused on acute reactivity during stressful tasks, there is some theoretical and empirical reason to believe that examining recovery and later re-creations of BP responses may also be useful. Two experiments explored situational determinants of sustained BP elevations, examining whether the extent of recovery and the ability to later mentally recreate the response are influenced by the magnitude or emotionality of the initial task and also whether preventing rumination after a stressor has ended speeds recovery. METHOD: Experiment 1, with 72 normotensive male and female undergraduates, examined BP and heart rate before, during, and after a task and also before, during, and after the mental re-creation of that task. Four tasks were used, designed to produce high initial reactivity with an emotional component (mental arithmetic with harassment), low reactivity with emotion (shock avoidance), high reactivity without emotion (physical exercise), or low reactivity without emotion (cold pressor). Experiment 2, with 20 normotensive male and female undergraduates, compared the cardiovascular recovery of persons who were either given a distractor task or just sat quietly immediately after a mental arithmetic task. RESULTS: Study 1 revealed that only the emotional tasks were associated with delayed BP recovery and elevations during later rumination. Blood pressure during recovery and later rumination was independent of the original reactivity. Experiment 2 found that participants with the distractor, who presumably could not ruminate, showed better BP recovery. CONCLUSIONS: Situations that put people at risk may include not just those that cause large BP elevations, but also emotion-producing situations that lead to sustained and recurring elevations.

Adult↗
PubMed1998

Synthetic peptide vaccines yield monoclonal antibodies to cellular and pathological prion proteins of ruminants.

Transmissible spongiform encephalopathies are closely linked to the accumulation of a pathological isoform of a host-encoded prion protein (PrP(C)), designated PrP(Sc). In an attempt to generate mono- and polyclonal antibodies to ruminant PrP, 32 mice were vaccinated with peptide vaccines which were synthesized according to the amino acid sequence of ovine PrP. By this approach five PrP-reactive polyclonal antisera directed against four different domains of the protein were stimulated. Splenocytes of mice which had developed PrP-reactive antibodies were used for the generation of monoclonal antibodies (MAbs). Obtained PrP-specific MAbs were directed to three different domains of ruminant PrP which differed from the three previously described major MAb binding sites in rodent PrP. MAbs exhibited reactivity with non-denatured ruminant PrP(C) in ELISA and immunoprecipitation and with denatured ovine and bovine PrP(Sc) in immunoblot. Cross-reactivity was observed with PrP(C) of nine other mammalian species and with pathological PrP preferably of ruminants and weakly with that of hamster and mouse. The generated MAbs will be useful tools for the development of diagnostic tests for BSE and scrapie as well as for pathogenesis studies of these diseases.

Amino Acid Sequence↗
PubMed1980

Pancreatic ribonucleases of mammals with ruminant-like digestion. Amino-acid sequences of hippopotamus and sloth ribonucleases.

High levels of pancreatic ribonucleases are found in ruminants, species that have a ruminant-like digestion and several species with coecal digestion. Pancreatic ribonucleases from several independently evolved species with ruminant-like digestion were investigated to test a hypothesis that glycosylation of ribonucleases may have some function in species with coecal digestion and that glycosylation of the enzyme may not be advantageous for ruminants. Ribonucleases from the hippopotamus, two-toed sloth and three-toed sloth were isolated by extraction with sulfuric acid and affinity chromatography. Complete amino acid sequences were determined for the ribonucleases from the hippopotamus and two-toed sloth and a partial sequence for the enzyme from the three-toed sloth. The amino acids 75-78 of hippopotamus ribonuclease were positioned by homology with other artiodactyl ribonucleases. In hippopotamus ribonuclease a heterogeneity was found at position 37, half of the molecules containing glutamine acid the other half lysine. Hippopotamus ribonuclease differs less from pig and bovine ribonuclease than these differ from each other, because more ancestral characteristics have been retained. Although hippopotamus ribonuclease contains all four Asn-X-Ser/Thr sequences previously found to be glycosylation sites in one or more pancreatic ribonucleases, only the sequence Ans-Met-Thr (34-36) is glycosylated in the variant with glutamine at position 37, while the variant with lysine at this position is carbohydrate-free. Both sloth ribonucleases are completely glycosylated at the sequence Ans-Met-Thr (34-36) with a simple type of carbohydrate chain. The amino acid sequence of two-toed sloth ribonuclease shows some interesting coupled replacements.

Amino Acid Sequence↗
PubMed1994

Is lamina muscularis mucosae present in the ruminal mucosa of cattle? Immunohistochemical and ultrastructural approaches.

The cells in the condensed fibrous layer in the lamina propria of the ruminal mucosa of the calves and cows were studied at the light microscopic level. Abundant actin-immunoreactive cells were detected both in the calves and cows, while desmin-immunoreactive cells were moderate in frequency in the cows and low or absent in the calves. Vimentin-immunoreactive cells were abundant in the cows but moderate to low in frequency in the calves. These cells were distributed to form a condensed layer being more abundant in the ruminal papillae than the interpapillar mucosae in the cows and equal in the papillae and interpapillar mucosae in the calves. At the ultrastructural level, smooth muscle cells and fibroblasts were abundant in the deep core of the ruminal papilla of the cows. The present results suggest that the condensed fibrous layer revealed in the ruminal mucosae contains smooth muscle cell population which could be regarded as the specialized lamina muscularis mucosae.

Animals↗
PubMed2006

Effect of supplemental yeast culture and sodium bicarbonate on ruminal fermentation and blood variables in rams.

A trial was conducted to evaluate the effect of sodium bicarbonate (BC) and Saccharomyces cerevisiae, live yeast culture (yea sacc(1026), YS) on ruminal fermentation and blood variables. Four Kivircik rams with ruminal cannula were used in a Latin square design, during 27-day periods (20 days for adaptation and 7 days for collection). They received 0 (control group), 5 g/day (i.e. 25 x 10(9) CFU) of YS or 10 g/day of sodium BC or 10 g/day of BC and 5 g/day of YS (BC + YS) (treatment groups). The cultures and sodium BC were added to the ration in a grain mix. The ration consisted of 70% grain mix and 30% lucerne hay. Rumen contents were collected before and 3 h and 6 h after morning feeding on days 1 and 7 in each collection period and were analyzed. Blood samples were also collected on the same days. Ruminal pH at 3 h (p < or = 0.1) and 6 h (p < or = 0.05) after feeding were higher when rams were fed BC and BC + YS than when they were fed CG and YS. Addition of YS to the diet did not modify the proportions of the different protozoa types; only Diplodinium at 0 h tended to be lower (p < 0.1) when rams were fed YS, BC and BC + YS than when they were fed CG. Plasma sodium value decreased by YS and BC + YS. Other biochemical and haematological variables were not affected by treatments. Also total volatile fatty acid, NH3-N concentrations and protozoa counts in the ruminal fluid were not affected by treatments.

Animal Nutritional Physiological Phenomena↗
PubMed1990

Rumination may be stimulated by a recording balloon in the reticulum of the sheep.

Rumination activity was recorded by three different methods in five sheep which had been fasted for 12 hours. When a balloon on plastic tubing was passed into the reticulum via a rumen cannula there was significantly more rumination recorded during the subsequent three hours than when rumination was recorded by registering jaw movements alone. The greater part of this stimulation occurred in the first half hour of recording. There was a significantly greater effect when the tubing to the reticulum balloon was stiffened with wire. Care is needed in comparing rumination times determined by different procedures.

Animals↗
PubMed2004

D-Lactic acidosis in calves as a consequence of experimentally induced ruminal acidosis.

In order to test the hypothesis that ruminal drinking in calves can lead to D-lactic metabolic acidosis, ruminal acidosis was induced in nine calves by intraruminal application of untreated whole milk via a stomach tube. The amount of the daily force-fed liquid was 3 x 1 l. The experimental design called for an end of intraruminal applications if two or more of the following signs were observed: severe depression, estimated degree of dehydration >10%, absence of sucking reflex, lack of appetite for two consecutive feedings, severe metabolic acidosis with calculated Actual Base Excess (ABE) <-15 mmol/l. The procedure was scheduled to be discontinued on the 17th day of experiment. The onset of ruminal acidification occurred rapidly, and mean pH value fell from 6.70 (+/-0.48) to 4.90 (+/-0.38) after the first application. The following days the pH values varied between 4 and 5. Rumen acidity was characterized biochemically by a significant increase in both isomers of lactic acid. The effects of the intraruminal administration on the calves were detrimental; eight of nine calves showed an acute disease process. According to the pre-established clinical standard, seven of nine calves were removed from the intraruminal feeding schedule. All but one of the calves developed severe systemic acidosis. The increase in anion gap demonstrated the net acid load. In all the calves D-lactate levels were found to show a significant and rapid increase. On the contrary, L-lactate never deviated from physiological levels. These observations confirm that, in young calves as in adult cattle, ruminal acidosis may lead to a clinically manifested D-lactic metabolic acidosis.

Acidosis, Lactic↗
PubMed1999

Regulatory role of cAMP in transport of Na+, Cl- and short-chain fatty acids across sheep ruminal epithelium.

Sodium is absorbed in considerable amounts across the ruminal epithelium, whilst its transport is strongly interrelated with the permeation of chloride and short-chain fatty acids (SCFAs). However, regulation of ruminal Na+, Cl-, and SCFA absorption is hardly understood. The present study was therefore performed to characterize the influence of cAMP on sodium and sodium-coupled transport mechanisms in short-circuited, stripped ruminal epithelia of sheep. Elevation of intracellular cAMP concentrations by theophylline (10 mM) or theophylline in combination with forskolin (0.1 mM) significantly reduced mucosal-to-serosal sodium transport, leading to a reduction of net transport. The theophylline- or theophylline-forskolin-induced reduction of sodium transport was accompanied by a decrease in chloride net transport but revealed no effect on propionate flux. Short-chain fatty acids stimulated Na+ transport but their stimulatory effect was almost completely blocked by theophylline-forskolin. In solutions with and without SCFAs, the inhibitory effect of 1 mM amiloride on sodium transport was strongly reduced after theophylline-forskolin pretreatment of the tissues. Blocking the production of endogenous prostaglandins by addition of indomethacin (10 microM) led to a theophylline-sensitive stimulation of unidirectional and net fluxes of sodium. The findings indicate that apical, amiloride-sensitive Na+-H+ exchange and/or basolateral Na+-K+-ATPase can effectively be blocked by cAMP, leading to a decrease in sodium and chloride transport. In the ruminal epithelium, cAMP is a second messenger of prostaglandins, which are released spontaneously under in vitro conditions.

Animals↗
PubMedDate not supplied

Radical mastectomy in 20 ruminants.

OBJECTIVE: To describe a surgical technique for radical mastectomy in ruminants and to report experience and outcome in 20 animals. STUDY DESIGN: Retrospective study. ANIMALS: Seventeen goats and 3 cows. METHODS: Medical records of ruminants that had radical mastectomy between June 1, 1987 and June 1, 2003 were reviewed. Follow-up information was obtained by telephone interview of owners. RESULTS: One animal died within 24 hours from complications of gangrenous mastitis and another died from necrotizing cellulitis. Eighteen animals were discharged and follow-up information was available for 15 animals; 12 animals lived at least 1 year postoperatively. CONCLUSIONS: Ruminants with severe but localized diseases of the udder did well after radical mastectomy. The procedure was well tolerated, made the animals more comfortable, and potentially prolonged their lives as pets. CLINICAL RELEVANCE: Radical mastectomy can be a safe and effective procedure for ruminants with udder disease, with few complications.

Animals↗
PubMed1994

Biochemical and biological characterization of ruminal Fusobacterium necrophorum.

Biochemical characteristics, biological activities, and antimicrobial susceptibilities of ruminal Fusobacterium necrophorum (eight subsp. necrophorum and eight subsp. funduliforme) and of isolates (three of each subsp.) obtained from bovine hepatic abscesses were determined. F. necrophorum subsp. necrophorum strains had higher phosphatase and DNase activities, produced more leukotoxin, and were more pathogenic to mice than subsp. funduliforme strains. The leukotoxin titer for culture supernatants of ruminal subsp. necrophorum strains was approximately 15 times lower than that of hepatic subsp. necrophorum strains. Hemagglutination activity was present in all hepatic, but only in some ruminal, strains of subsp. necrophorum. The antimicrobial sensitivity profile of the ruminal isolates was similar to that of hepatic isolates.

Animals↗
PubMed1967

An electrophysiological study of some reticulo-ruminal and abomasal reflexes in sheep.

1. In halothane-anaesthetized sheep in which reticulo-ruminal (gastric) contractions were present, nervous discharges have been recorded electrophysiologically in sixty-four single efferent gastric units (grouped in seven types) dissected from the mid-cervical region of the left vagus. An examination was made of the reflex effects on the efferent discharges of the procedures given in paragraphs 2-5.2. Under isotonic recording conditions the total discharge was reduced but the peak frequency of most types of unit was enhanced compared with the discharge recorded under control isometric conditions.3. Abolition of reticular contractions by the use of preganglionic and post-ganglionic blocking agents resulted in an efferent discharge pattern similar to that recorded under isotonic conditions.4. Sudden deflation or inflation of the reticulum at the start of a reticular contraction had an effect that depended on the initial volume of the reticulum. It could be either excitatory and/or inhibitory.5. Acidification of the abomasal contents reflexly enhanced the discharge in three of ten efferent gastric vagal units. An abomasal pH less than 1.0 appears to be less important in providing an excitatory drive to the ;gastric centres' in halothane-anaesthetized sheep than in decerebrate sheep.6. It is estimated that the total reflex time is > 1.3 sec for reticulo-reticular reflexes and > 2.1 sec for reticulo-ruminal reflexes. The central reflex time is > 370 msec.7. It is concluded that a tonic afferent input from ;in series' reticular tension receptors during the quiescent period of the primary (reticulo-ruminal) cycle provides a reflex drive to the ;gastric centres' and largely determines the rate and amplitude of the reticular and ruminal contractions.8. The enhanced afferent input, during a reticular contraction under isometric recording conditions, modifies the size, form and duration of the later phases in the contraction sequence of the reticulum and rumen. The reflex effects are predominantly excitatory at low and moderate levels of reticular tension and inhibitory at high levels.

Journal Article↗
PubMed1987

Effect of hydrophobicity of utilization of peptides by ruminal bacteria in vitro.

When mixed ruminal bacteria were incubated with a pancreatic casein hydrolysate and free amino acids of a similar composition, rates of ammonia production were much greater for peptides than for amino acids. The pancreatic digest of casein was then fractionated with 90% isopropyl alcohol. Hydrophobic peptides which dissolved in alcohol contained an abundance of phenolic and aliphatic amino acids, while the hydrophilic peptides which were precipitated by alcohol contained a large proportion of the highly charged amino acids. The Km values of the mixed ruminal bacteria for each fraction were similar (0.88 versus 0.98 g/liter), but the Vmax of the hydrophilic peptides was more than twice that of the hydrophobic peptides (18 versus 39 mg of NH3 per g of bacterial protein per h). Pure cultures of ruminal bacteria had a similar preference for hydrophilic peptides and likewise utilized peptides at a faster rate than free amino acids. Since peptide degradation rates differed greatly, hydrophobicity is likely to influence the composition of amino acids passing unfermented to the lower gut of ruminant animals.

Amino Acids↗
PubMed1989

Most-probable-number procedures for enumerating ruminal bacteria, including the simultaneous estimation of total and cellulolytic numbers in one medium.

Based on results from eight experiments, no overall difference was found between roll tube and three- and five-tube most-probable-number (MPN) methods for estimating total numbers of ruminal bacteria. However, standard errors for the replicate means within an experiment were higher with the MPN procedures. Visual growth and pH were the criteria used for scoring the MPN tubes. Total numbers were significantly higher in MPN medium containing 40% ruminal fluid, as compared with a complete medium without ruminal fluid. By using a broth medium containing ball-milled cellulose and soluble carbohydrates as energy sources, it was possible to estimate both total and cellulolytic ruminal bacterial numbers in the same MPN series. Disappearance of cellulose and decrease in pH were used to determine growth. Values did not differ from those obtained in separate MPN assays. By using this method, diurnal changes in total and cellulolytic bacterial numbers were estimated in sheep fed forage or a concentrate-type diet.

Animals↗
PubMed1993

Effect of monensin on the specific activity of ammonia production by ruminal bacteria and disappearance of amino nitrogen from the rumen.

When unadapted mixed ruminal bacteria (312 mg of protein per liter) were treated with monensin (5 mM) in vitro, the rates of ammonia production from enzymatic digests of casein, gelatin, and soy protein (0.5 g of N per liter) were decreased from 46 +/- 2 to 24 +/- 1, 20 +/- 1 to 7 +/- 1, and 40 +/- 2 to 18 +/- 2 nmol/mg of protein per min, respectively. Monensin also caused a decrease in ammonia production in vivo. Nonlactating dairy cows which were fed 0.56 kg of timothy hay 12 times per day had a steady-state ruminal ammonia concentration of 2.7 +/- 0.1 mM, and the ammonia concentration decreased to 1.2 +/- 0.2 mM when monensin (350 mg/day) was added to the diet. The decrease in ammonia production was associated with a 10-fold reduction (4.1 x 10(6) versus 4.2 x 10(5)/ml) in the most probable number of ammonia-producing ruminal bacteria that could use protein hydrolysate as an energy source. Monensin had little effect on the most probable number of carbohydrate-utilizing ruminal bacteria (6.5 versus 7.0 x 10(8)/ml). The addition of protein hydrolysates (560 g) to the rumen caused a rapid increase in the ammonia concentration, but this increase was at least 30% lower when the animals were fed monensin.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1996

Ribotyping to differentiate Fusobacterium necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme isolated from bovine ruminal contents and liver abscesses.

Differences in biological activities (hemagglutination, hemolytic, leukotoxic, and virulence) and ribotypes between the two subspecies of Fusobacterium necrophorum of bovine ruminal and liver abscess origins were investigated. Hemagglutination activity was present in all hepatic, but only some ruminal, strains of Fusobacterium necrophorum subsp. necrophorum. Ruminal F. necrophorum subsp. necrophorum had low leukotoxin titers yet was virulent in mice. Fusobacterium necrophorum subsp. funduliforme of hepatic or ruminal origin had no hemagglutination activity, had low hemolytic and leukotoxic activities, and was less virulent to mice. For ribotyping, chromosomal DNAs of 10 F. necrophorum subsp. necrophorum and 11 F. necrophorum subsp. funduliforme isolates were digested with restriction endonucleases (EcoRI, EcoRV, SalI, PstI, and HaeIII) and examined by restriction fragment length polymorphisms after hybridizing with a digoxigenin-labeled cDNA probe transcribed from a mixture of 16 and 23S rRNAs from Escherichia coli. The most discriminating restriction endonuclease enzyme for ribotyping was EcoRI. The presence or absence of two distinct bands of 2.6 and 4.3 kb differentiated the two subspecies. Regardless of the origin, only F. necrophorum subsp. necrophorum, a virulent subspecies, had a ca. 2.6-kb band, whereas F. necrophorum subsp. funduliforme, a less virulent subspecies, had a ca. 4.3-kb band. Ribotyping appears to be a useful technique to genetically differentiate the two subspecies of F. necrophorum.

Animals↗
PubMed1997

Effect of 2-bromoethanesulfonic acid and Peptostreptococcus productus ATCC 35244 addition on stimulation of reductive acetogenesis in the ruminal ecosystem by selective inhibition of methanogenesis.

Evidence is provided that reductive acetogenesis can be stimulated in ruminal samples during short-term (24-h) incubations when methanogenesis is inhibited selectively. While addition of the reductive acetogen Peptostreptococcus productus ATCC 35244 alone had no significant influence on CH4 and volatile fatty acid (VFA) production in ruminal samples, the addition of this strain together with 2-bromoethanesulfonic acid (BES) (final concentration, 0.01 or 0.03 mM) resulted in stimulation of acetic acid production and H2 consumption. Since acetate production exceeded amounts that could be attributed to reductive acetogenesis, as measured by H2 consumption, it was found that P. productus also fermented C6 units (glucose and fructose) heterotrophically to mainly acetate (> 99% of the total VFA). Using 14CH3COOH, we concluded that addition of BES and BES plus P. productus did not alter the consumption of acetate in ruminal samples. The addition of P. productus to BES-treated ruminal samples caused supplemental inhibition of CH4 production and stimulation of VFA production, representing a possible energy gain of about 13 to 15%.

Acetic Acid↗