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PubMedDate not supplied

Ruminant alphaherpesviruses related to bovine herpesvirus 1.

Herpesviruses have mainly co-evolved with their hosts for millions of years. Consequently, different related host species may have been infected by various genetically related herpesviruses. Illustrating this concept, several ruminant alphaherpesviruses have been shown to form a cluster of viruses closely related to bovine herpesvirus 1 (BoHV-1): namely bovine herpesvirus 5, bubaline herpesvirus 1, caprine herpesvirus 1, cervid herpesviruses 1 and 2 and elk herpesvirus 1. These viruses share common antigenic properties and the serological relationships between them can be considered as a threat to BoHV-1 eradication programmes. BoHV-1 is a herpesvirus responsible for infectious bovine rhinotracheitis, which is a disease of major economic concern. In this article, the genetic properties of these ruminant alphaherpesviruses are reviewed on a comparative basis and the issue of interspecific recombination is assessed. The pathogenesis of these infections is described with emphasis on the host range and crossing of the host species barrier. Indeed, the non bovine ruminant species susceptible to these ruminant alphaherpesviruses may be potential BoHV-1 reservoirs. The differential diagnosis of these related infections is also discussed. In addition, available epidemiological data are used to assess the potential of cross-infection in ruminant populations. A better knowledge of these ruminant alphaherpesvirus infections is essential to successfully control infectious bovine rhinotracheitis.

Alphaherpesvirinae↗
PubMed1992

Determining optimal heat treatment of soybeans by measuring available lysine chemically and biologically with rats to maximize protein utilization by ruminants.

Soybeans were heated in a forced air oven at 120 and 130 degrees C for 60 and 180 min, and at 140, 150 and 160 degrees C for 10, 30, 60, 90 and 120 min. Two types of measurements were used to determine optimal heat treatment of soybeans to maximize protein utilization by ruminants. One was to estimate the rate and extent of protein degradation in the rumen using an in vitro ruminal system. The second was to determine the nutritional availability of lysine. Methods used to determine available lysine were an indirect fluorodinitro-benzene chemical method and a rat growth assay. The product of undegraded intake protein and available lysine content was used to estimate the amount of lysine that would escape ruminal degradation and be available for intestinal absorption. As heat input increased, ruminal undegraded intake protein increased, and protein degradation rates and total and available lysine decreased. As temperature increased, the time required to maximize post-ruminal available lysine decreased. The optimal heat treatment for soybeans heated in a forced air oven was: 140 degrees C for 120 min or greater, 150 degrees C for 60 min or 160 degrees C for 30 min. A loss of 15-22% of chemically determined available lysine was necessary to achieve the heat treatment that resulted in maximal post-ruminal available lysine.

Animals↗
PubMedDate not supplied

Influence of diet on the rumen protozoal fauna of indigenous African wild ruminants.

A study was carried out to determine if the protozoal fauna of indigenous African wild ruminants was different from that found in their domestic counterparts and if the animal's diet influenced the number and types of protozoa. Samples of rumen contents were collected in 1997 and 2001 from various indigenous African wild ruminants in Kenya. All three ruminant feeding types were sampled: browsers or concentrate selectors (giraffe and Guenther's dik-dik); intermediate or adaptable mixed feeders (impala, Thomson's gazelle, Grant's gazelle and eland); grass or roughage eaters (hartebeest and wildebeest). Total concentration of ciliate protozoa and percentage generic distribution were determined. In general, protozoal concentrations were higher in concentrate selectors, followed by the intermediate or opportunistic mixed feeders and lowest in the grass and roughage eaters. Both Thomson's and Grant's gazelle were protozoa-free in the 2001 samples. Entodinium percentages were considerably higher in concentrate selectors and intermediate mixed feeders, compared to roughage eaters. Two genera of protozoa previously found in only a few African ruminants, Epiplastron and Opisthotrichum, were observed in several additional animal species and represent new host records. A difference was noted in the protozoal species composition of the indigenous wild ruminants from that previously observed in African domestic ruminants.

Africa↗
PubMed1994

Treatment of ruminal indigestion according to popular belief in Sweden.

For hundreds of years, the Swedish peasantry were able to cure diseases of animals by using various popular remedies. In this context, ruminal indigestion is a disease of special interest to veterinary history. Long before research had demonstrated the importance for rumination of the ruminal microflora and microfauna, the Swedish peasantry used to administer living ruminal microorganisms from a healthy cow or sheep to an animal suffering from ruminal indigestion. This was performed by giving the diseased animal a cud obtained from the healthy animal. According to some beliefs, the cud was a living being. Those cherishing this belief therefore thought it wise to take only part of the cud so as not to harm the involuntary donor. Another common treatment of ruminal indigestion was based on the thought that the cow had lost the ability to chew. The authors describe the frequent use of chewing of various substances as a remedy. In the available literature, some forty different remedies have been described either alone or used in combination with the above principles.

Animals↗
PubMed1998

Manipulation of ruminal fermentation with organic acids: a review.

The dicarboxylic acids aspartate, fumarate, and malate stimulate lactate utilization by the predominant ruminal bacterium, Selenomonas ruminantium. Malate stimulates lactate uptake by S. ruminantium more than does aspartate or fumarate, and it seems that malate and sodium are involved in stimulating lactate utilization by this bacterium. Based on the ability of S. ruminantium to grow on malate in the presence of extracellular hydrogen and produce succinate, malate may be acting as an electron sink for hydrogen in the succinate-propionate pathway used by S. ruminantium. Incorporation of DL-malate into soluble starch and cracked corn fermentations with mixed ruminal microorganisms changed final pH, CH4, and VFA in a manner analogous to ionophore effects. When compared with either dicarboxylic acids or monensin alone, dicarboxylic acid plus monensin addition to cracked corn incubations stimulated the mixed ruminal microorganism fermentation to produce more propionate, less lactate, and increased final pH. Reduced lactate concentrations in dicarboxylic acid- and monensin-treated incubations most likely represents an additive effect of decreased lactate production by monensin-sensitive bacteria (i.e., Streptococcus bovis) and increased lactate utilization by the monensin-resistant S. ruminantium. The inclusion of malate as a feed additive into the diets of ruminants is currently not economically feasible; however, forages rich in organic acids might serve as vehicles for providing malate to ruminants. When five alfalfa varieties and three bermudagrass hay varieties were surveyed for malate content, the concentration of malate in both plant species declined as maturity increased. However, after 42 d of maturity, the concentration of malate in both forages ranged between 1.9 and 4.5% of the DM. These results suggest that the incorporation of forage varieties that are high in malate may include malate economically into the diet and reduce losses associated with ruminal acidosis.

Animals↗
PubMed1998

Demonstration of a carrier state for Cowdria ruminantium in wild ruminants from Africa.

Four wild African ruminants, eland (Taurotragus oryx), giraffe (Giraffa camelopardalis), kudu (Tragephalus strepsiceros strepsiceros), and blue wildebeest (Connochaetes taurinus), were experimentally infected with the rickettsia Cowdria ruminantium, the tickborne agent causing heartwater in domestic ruminants. The infections were established, and C. ruminantium was transmitted to naive small ruminants by the vector Amblyomma hebraeum when transmission attempts were made at days 128 (eland and wildebeest), 85 (giraffe), and 24 (kudu) post infection. These wild ruminants, which are natural hosts for the tick vector, and which commonly occur within heartwater-endemic areas of Africa, are likely to play important roles in the epidemiology of heartwater as reservoirs of C. ruminantium infection. These findings also demonstrate that considerable risks are associated with the translocation of wild ruminants from heartwater-endemic areas to heartwater-free areas such as the northern and southern American mainlands, which have large populations of susceptible domestic and wild ruminant hosts and tick species that are capable of transmitting the disease.

Animals↗
PubMed1985

Alleviation of excessive gas accumulation in the ruminant stomach by ritanserin.

The relationships between forestomach motility and eructation rate were studied in sheep and cattle. Three ewes and 2 heifers were implanted with strain gauges on the reticulo-rumen and fitted with a cannula in the dorsal sac of the rumen. Studies were performed in sheep after induction of hypocalcemia by Na2EDTA infusion and cattle were studied after ruminal distension. Experiments were performed by measuring the rate and volume of eructated ruminal gases, using a technique by which the trachea is transected. The frequency of reticulo-ruminal contractions decreased 40% within 30 minutes of Na2EDTA infusion to the sheep. The volume of eructated gas (for 30-minute periods) decreased from 10.7 L to 5.5 L at the end of the 60-minute infusion period. Pretreatment with ritanserin (0.1 mg/kg, subcutaneously) not only prevented bloating during the ruminal stasis induced by hypocalcemia, but also significantly increased the eructated volume of gas. In cattle, ritanserin given at the same dose level (0.1 mg/kg, subcutaneously) significantly increased the volume of eructated gas after ruminal distension. This study supports the hypothesis that the caudal esophageal sphincter has a role in the rate of ruminal gas eructation and indicates that its relaxation may be due to a 5-hydroxytryptamine antagonist.

Animals↗
PubMed2007

Ruminative coping among patients with dysthymia before and after pharmacotherapy.

The pivotal role of rumination in relation to other coping strategies was assessed in chronically depressed (dysthymic disorder) individuals versus nondepressed controls. Individuals with dysthymia demonstrated elevated use of rumination and other emotion-focused strategies (emotional expression, emotional containment, self- and other-blame). Among patients with dysthymia, rumination was linked to this limited array of emotion-focused efforts and diminished use of cognitive disengagement, whereas among controls, rumination was correlated with a broad constellation of problem- and emotion-focused strategies. Following 12 weeks of pharmacotherapy (sertraline), despite attenuation of depressed mood and reduced rumination, the limited relations between rumination and emotion-focused efforts persisted. Inflexibility in the ability to combine various coping efforts effectively may be characteristic of individuals with dysthymia, potentially increasing risk for recurrence.

Adaptation, Psychological↗
PubMed1996

Pretreatment of sugar cane bagasse for enhanced ruminal digestion.

Crop residues, such as sugar cane bagasse (SCB), have been largely used for cattle feeding. However, the close association that exists among the three major plant cell-wall components, cellulose, hemicellulose, and lignin, limits the efficiency by which ruminants can degrade these materials. Previously, we have shown that pretreatment with 3% (w/w) phosphoric acid, under relatively mild conditions, increased considerably the nutritional value for SCB. However, in this preliminary study, pretreated residues were not washed prior to in situ degradability assays because we wanted to explore the high initial solvability of lowmol-wt substances that were produced during pretreatment. We have now studied the suitability of water-and/or alkali-washed residues to in situ ruminal digestion. Alkali washing increased substrate cellulose content by removing most of the lignin and other residual soluble substances. As a result the ruminal degradability of these cleaner materials had first-order rate constants five times higher than those substrates with higher lignin content (e.g., stem-exploded bagasse). However, alkali washing also increased the time of ruminal lag phase of the cellulosic residue, probably because of hemicellulose and/or lignin removal and to the development of substrates with higher degree of crystallinity. Therefore, longer lag phases appear to be related to low microbial adherence after extensive water and alkali extraction, as Novell as to the slower process of cellulase induction during ruminal growth. The kinetic data on ruminal digestion were shown to be very well adjusted by a nonlinear model. Although pretreatment enhances substrate accessibility, the occurrence of an exceedingly high amount of lignin byproducts within the pretreated material reduces considerably its potential degradability.

Alkalies↗
PubMed2006

Rumination in eating disorders: literature review.

Rumination is defined as regurgitation of partially digested food that is subsequently re-chewed and then swallowed or ejected by mouth. We report a case of rumination and a review of selected literature to emphasize: 1. Risk factors for rumination in eating disorders are unknown, 2. A history of rumination must be taken routinely because shame prevents patients from volunteering this history, 3. Rumination usually lessens with improvement of the eating disorder, but other methods including behavior modification, breathing techniques, and gum chewing have shown success in individual cases or small case series. There have been no controlled trials published of any treatment for rumination in eating disorders.

Adolescent↗
PubMed1993

The use of thermostable Vero cell-adapted rinderpest vaccine as a heterologous vaccine against peste des petits ruminants.

The thermostable Vero cell-adapted rinderpest vaccine was evaluated in terms of immunogenicity as a heterologous vaccine against peste des petits ruminants. A titration to establish the minimum immunising dose was performed in American mixed breed goats by vaccinating test subjects with dilutions of Vero cell-adapted rinderpest vaccine and then challenging 26 days later with virulent peste des petits ruminants virus. All animals were followed for virus neutralising antibodies against both rinderpest and peste des petits ruminants virus after vaccination and challenge. The antibody response to vaccination was primarily against rinderpest virus with very low levels of cross-reactivity to peste des petits ruminants virus. Following challenge, animals which possessed anti-rinderpest neutralising antibodies remained clinically normal but mounted strong anti-peste des petits ruminants virus neutralising antibody responses indicating that replication of challenge virus took place without the induction of illness. The 50 per cent minimum goat immunising dose was 3 tissue culture infectious doses 50 per cent (TCID50) as established by serological response and protection against challenge. The thermostable Vero cell-adapted rinderpest vaccine is a suitable immunogen for the protection of goats against peste des petits ruminants.

Animals↗
PubMed1992

Glucose and insulin metabolism in ruminating and veal calves fed high and low fat diets.

Holstein male calves were maintained on conventional (milk to 6 wk of age, fed grain and hay after weaning) and veal (milk replacer only) diets to 16 wk of age. Within each of these 2 physiological states (ruminating or non-ruminating), calves were fed low or high fat diets (ruminating: 3 and 10%; veal: 10 and 18%). Glucose tolerance tests were undertaken at 8 and 16 wk of age in each group. Basal concentrations (4 hr postfeeding) and areas under the response curves for plasma glucose and insulin were higher in veal calves (P < .0001). Ruminating calves fed higher fat utilized glucose more readily (smaller areas under the curves for both glucose and insulin, P < .10) than those fed lower fat. Age did not influence basal glucose concentrations (P > .10), but older calves had higher basal insulin (P < .0001) and greater areas under the curves (P < .0005) for both glucose and insulin after a glucose challenge. Rate of clearance (k) was greater in ruminating calves (P < .001). Though rate of clearance in veal calves was slower, larger plasma pool size caused veal calves on average to utilize glucose at a 15% greater rate per kg body weight than ruminating calves. Whereas fat concentration in the diets did not influence glucose metabolism in veal calves, the high lactose content (> 50% of diet dry matter) of veal diets induced severe insulin resistance in these calves.

Animals↗
PubMed2005

Comparisons between rumination and worry in a non-clinical population.

Major depression is characterised by ruminative thinking whilst worry is considered central in generalised anxiety disorder (GAD). However, not only do these two forms of repetitive negative thinking regularly co-occur in the same individual but similarities between worry and rumination are apparent. Adapting a methodology developed by Langlois et al. (Behav. Res. Therapy 38 (2000) 157-173), this study directly compared worry and rumination in a non-clinical population across a series of variables drawn from current models (appraisal, general descriptors and emotional reactions). Each of 149 female volunteers, with a wide range of age and backgrounds, identified a ruminative thought and a different worry and subsequently evaluated them using the Cognitive Intrusion Questionnaire. Significant within-subject differences were revealed on seven variables: chronicity, unpleasantness, reality of problem, future orientation, past orientation, feelings of worry and insecurity. There were no differences found between worry and rumination on appraisals and strategies, consistent with accounts that propose that worry and rumination share the same processes but involve different content (Cognitive Ther. Res. 24 (2000) 671-688).

Adult↗
PubMed2006

Social anxiety, depressive symptoms, and post-event rumination: affective consequences and social contextual influences.

Using a self-presentation perspective, we hypothesized that during social interactions in which social attractiveness could be easily appraised by others, more socially anxious individuals would be more prone to ruminate and rumination would have more adverse emotional consequences. After assessing social anxiety and depressive symptoms, unacquainted college students participated in 45-min structured social interactions manipulated to induce personal self-disclosure or mimic superficial, small-talk. Affective experiences were assessed immediately after and 24h after social interactions. Results found that social anxiety was associated with negative post-event rumination more strongly among those with elevated depressive symptoms. Further, at higher levels of social anxiety, post-event rumination was associated with increases in NA following personal disclosure interactions and decreases in NA following small-talk interactions. Individuals with more depressive symptoms experienced increases in NA following small-talk interactions, but not personal disclosure interactions. Contrary to expectation, positive relations between social anxiety and rumination were not mediated by self-presentation concerns during interactions. Fitting with relevant theory, findings implicated symptom and social contextual variables that moderate the affective consequences of rumination.

Adult↗
PubMed1997

Ruminative thinking in older inpatients with major depression.

Ruminative thinking, the tendency to dwell on particular ideas or themes, can be a prominent part of the phenomenology of major depression, but it rarely has been the focus of empirical research. We attempted to replicate (in adult psychiatric inpatients age > or = 50 years with DSM-III-R major depression) the previously published finding that ruminative thinking was associated with melancholia and with psychosis. In our sample, these associations were not present. In addition, we explored the relationships of ruminative thinking to specific areas of thought content (e.g., suicidal ideation, somatic worry), cognitive function and overall functional status; ruminative thinking was not associated with suicidal ideation, but was associated with greater somatic worry and with poorer functional status, although these associations were not independent of overall depressive severity. A substantial proportion of subjects were unable to complete the cognitive measures; ruminative thinking was independently associated with inability to complete these tasks. We conclude that ruminative thinking is a meaningful and common clinical phenomenon among severely depressed older inpatients. Further investigations in inpatients and other populations examining its relationships to other phenomenology, to course and outcome, and to putative underlying mechanisms of depression are warranted.

Adult↗
PubMed1999

Rumination and distraction in major depression: assessing response to pharmacological treatment.

BACKGROUND: Response style theory of depression (RST) predicts that individuals who ruminate in response to their depressed mood will suffer an amplification and prolongation of that mood, whereas individuals who engage in distraction responses will alleviate and attenuate their depressed mood. RST has been shown to predict prolonged depression in samples of non-clinical, untreated individuals with mild to moderate depression but has not been tested in samples of depressed patients undergoing treatment. OBJECTIVE: In this preliminary investigation we examined: (1) whether RST predicts non-response to pharmacotherapy with outpatients suffering from major depression, and (2) whether distractive and ruminative responses are associated with clinical variables hypothesized to be associated with them. METHODS: Eighty-nine depressed outpatients being treated with standard antidepressant pharmacotherapy were administered the Response Style Questionnaire, a scale designed to measure rumination and distraction, prior to treatment. RESULTS: Distraction, but not rumination, predicted change in depression severity over the course of treatment and overall treatment outcome. Neither rumination nor distraction was associated with previous number of depressive episodes or duration of current depressive episode. DISCUSSION: These results provide only partial support for RST as a predictor of treatment response. Future investigations are needed to determine if rumination and distraction are predictive of recurrent depressive episodes in recovered depressed patients. LIMITATIONS: As the data in this study was retrieved from a clinical database, the conclusions of this report must be viewed tentatively. Replication with other clinical samples is needed.

Adult↗
PubMed2004

Determination of methylglyoxal in ruminal fluid by high-performance liquid chromatography using fluorometric detection.

There is no reported method for the quantification of methylglyoxal in ruminal fluid. The method reported here is based on the conversion of methylglyoxal to 6-methylpterin, followed by quantification of the resulting pteridinic compound by fluormetric detection using liquid chromatography. Ruminal fluid was collected and preserved with 1 M HCl at -20 degrees C. Cation exchange prior to derivatization was used to eliminate possible interfering peaks. The detection limit of 0.125 microg/mL was calculated. The recoveries were >80%, and the coefficients of variation were <15%. This method has proven to be rugged and accurate for the detection of methylglyoxal concentration in ruminal fluid collected from cows fed diets deficient in degradable intake protein as a marker. Methylglyoxal is produced by ruminal bacteria in response to low nitrogen levels in the rumen. The ruminal methylglyoxal concentration has the potential to be a useful marker to assess ruminal nitrogen status to aid in more accurate diet formulation.

Animals↗
PubMed2004

High intake of magnesium in relation to the ruminal transmural potential difference and magnesium absorption in wethers.

High potassium (K) intakes are known to decrease magnesium (Mg) absorption in ruminants by increasing the transmural potential difference (PDt, serosal side = positive). High Mg intakes are known to increase the amount of Mg absorbed, which may be explained by increasing the ruminal Mg concentration, but an effect on the PDt cannot be excluded. The objective of this study was to determine whether or not Mg intake affects the PDt. In a 3 x 3 Latin square design, six ruminally fistulated wethers were fed a low-Mg, low-K ration (3.88 g Mg/kg dry matter (DM); 30.7 g K/kg DM), a high-Mg, low K-ration (16.79 g Mg/kg DM; 30.7 g K/kg DM), and a low-Mg ration high-K (3.88 g Mg/kg DM or 62.1 g K/kg DM). When compared with the low-Mg, low-K ration, the high-Mg, low-K ration raised the absolute apparent Mg absorption (g/day) by 421% and the low-Mg, high-K ration decreased it by 20%. The intake of extra K produced a significant increase in the PDt. The intake of extra Mg did not change the PDt across the rumen wall but produced a significant increase of the ruminal Mg concentrations. On the basis of the individual values for three rations, the mean post feeding ruminal Mg concentrations were found to be unrelated to the PDt (Pearson's r = -0.329, p = 0.183, n = 18). Thus, it is concluded that the observed increase in Mg absorption after a high Mg intake can be explained by an increase in the ruminal Mg concentration rather than by a change in PDt.

Absorption↗