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PubMedDate not supplied

Real-time polymerase chain reaction approach for quantitation of ruminant-specific DNA to indicate a correlation between DNA amount and meat and bone meal heat treatments.

The use of ruminant-derived proteins in ruminant feeds has been banned in both the European Union and the United States to prevent further spread of bovine spongiform encephalopathy. Enforcement of these regulations relies on the ability to identify the presence of prohibited proteins in feed. We developed a quantitative real-time polymerase chain reaction assay for the quantification of ruminant-specific DNA as index of protein content. The assay is based on the amplification of a 117 base pair mitochondrial 16S rRNA DNA gene fragment and an internal positive control (IPC). The use of an IPC permits compensation for differences in DNA extraction efficiency and avoids the occurrence of false-negative results. We demonstrated a decrease in target DNA amount with a difference of 2 logs between meat and bone meal (MBM) treated at 133 degrees and 145 degrees C. Such a difference indicates that bias could occur when DNA-based methods are used for quantitation purposes. Risk management could benefit from future efforts concerning validation of the method for MBM detection in feedstuff and safety evaluation of the use of animal-derived proteins in animal nutrition.

Animal Feed↗
PubMed1989

Prevalence of antibodies to alcelaphine herpesvirus-1 and nucleic acid hybridization analysis of viruses isolated from captive exotic ruminants.

A serologic survey was conducted to determine the prevalence of antibodies to alcelaphine herpesvirus-1 (AHV-1) in captive exotic ruminants within the United States. Forty-six percent of the members of the subfamily Alcelaphinae (wildebeest, topi, hartebeest) in the family Bovidae had virus-neutralizing antibody to AHV-1. Other subfamilies of Bovidae with high prevalence of virus-neutralizing antibodies to AHV-1 included Hippotraginae (oryx and addax) and Caprinae (sheep and goats), with prevalence of 45% and 29%, respectively. Herpesviruses that have been isolated from captive exotic ruminant species, including healthy animals and those with clinical malignant catarrhal fever at the Oklahoma City Zoo and the San Diego Zoo/Wild Animal Park, were analyzed by DNA restriction enzyme analysis and blot hybridization. Variation has been detected among the genomes of several malignant catarrhal fever virus isolates obtained from various exotic species of ruminants, using the DNA restriction enzymes BamHI and HindIII. The DNA of these virus isolates is distinct from that of bovine herpesviruses 1, 2, and 4, as demonstrated by restriction enzyme analysis and nucleic acid hybridization. On the basis of restriction enzyme analysis and nucleic acid hybridization data, the DNA from each of the putative alcelaphine herpesvirus isolates examined, except for the topi virus isolate, had a high degree of DNA sequence similarity with the original AHV-1 isolate, WC-11, from a blue wildebeest.

Animals↗
PubMed1988

[Findings and hormonal coordination of protein metabolism in ruminants].

Protein metabolism roughly exhibits the same characteristics in ruminants and non-ruminant species. Changes in whole-body protein mass are the result of the balance between the simultaneous protein synthesis and breakdown. Essential amino acids are either incorporated into protein or degraded. Insulin, growth hormone and glucagon have been shown to regulate those metabolic pathways in ruminants. Alteration of food intake both decreases protein synthesis and protein breakdown. Protein synthesis is affected to a greater extent than protein breakdown. So protein synthesis is the main factor controlling N balance in response to alteration of food intake. The decrease in protein synthesis may be related to an impairment of plasma insulin. Protein synthesis and breakdown both decrease throughout development. Protein deposition decreases throughout development because protein synthesis declines more rapidly than protein breakdown. The hormonal coordination of those changes depends on the age of the animals. For example the decrease in protein synthesis in the postnatal growth period may be due to either the decrease in plasma growth hormone or to the impairment in cellular insulin receptors. Due to milk protein synthesis in the mammary gland, lactating animals exhibit a large increase in whole-body protein synthesis. Surprisingly, protein synthesis decreases in some non-mammary tissues. This represents a mechanism for a greater partitioning of amino acids towards milk at the expense of body proteins. We recently demonstrated that insulin could be involved in that adaptative process.

Amino Acids↗
PubMed1995

Investigating local regulation of the testes of ruminants.

In addition to endocrine regulation by the gonadotrophic hormones, the functions of the testes are regulated locally by paracrine and autocrine factors. Some attempts have been made to isolate cells from the testes of immature bulls and rams for investigation of cell function in vitro. However, most studies have used in vitro cultures of cells isolated from the testes of rats and a large variety of factors have been identified as potential local regulators. This review examines the importance of Sertoli cell-germ cell interactions, Leydig cells and steroidogenesis, blood flow and vascular permeability, and cytokines and immune cells as local regulators of the testes. The small amount of work undertaken on the testes of ruminants is reviewed together with approaches such as the transilluminated dissection of staged seminiferous tubules and in vivo cell depletion models used with rats. The suitability and limitation of these approaches for ruminants are considered, and immunological and molecular probes are raised as options for future investigations of the local regulation of the testes of ruminants.

Androgens↗
PubMed1997

Phosphoprotein profile analysis of ruminant respiratory syncytial virus isolates.

OBJECTIVE: To determine the apparent molecular weight for 24 ruminant respiratory syncytial viruses (RSV) on the basis of differences in the electrophoretic mobility of the phosphoprotein (P protein). PROCEDURE: 29 bovine RSV (BRSV), 20 of which were not previously tested, 3 ovine RSV, and 1 caprine RSV isolates were selected for determination of electrophoretic mobility of the P protein. Virus radiolabeled with [35S]methionine was immunoprecipitated with polyclonal antiserum to BRSV and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. RESULTS: On the basis of apparent molecular size of the P protein, all isolates could be categorized into 2 electropherotypes, low molecular size of 36 kd and high molecular size of 38 kd. Twenty-three BRSV, the 3 ovine RSV, and 1 caprine RSV isolates had a high molecular size P protein; 6 BRSV isolates had a low molecular size P protein. CONCLUSIONS: The apparent molecular size of the P protein of the ruminant RSV strains is greater than that of the human RSV subgroups, providing further evidence of their distinctiveness. Whether categorization of electrophoretic mobility of the P protein of BRSV underlies distinct antigenic subgroups, as it does in human RSV, requires further antigenic and genetic analysis. CLINICAL RELEVANCE: Antigenic subgroups of ruminant RSV may have relevance in the development of new vaccines for control of the disease.

Animals↗
PubMed1998

A diet supplement for captive wild ruminants.

Nutritional husbandry of captive wild ruminants often requires feeding these animals a supplemental diet to enhance their health, reproductive performance, and productivity. Although supplemental diets for wild ruminants are commercially available, few have been evaluated in controlled intake and digestion trials. Voluntary intake, digestive efficiency, nitrogen retention, and gross energy utilization of pronghorn (Antilocapra americana), mule deer (Odocoileus hemionus), mountain sheep (Ovis canadensis), mountain goats (Oreamnos americanus), and wapiti (Cervus elaphus) consuming a high-energy, high-protein pelleted supplement were compared. Voluntary intake of dry matter, energy, and nitrogen were similar (P > 0.34) between mountain goats and mountain sheep and consistently lower (P < 0.03) for these species than for pronghorn, mule deer, and wapiti. Differences in digestive efficiency among species were inversely related to dry matter intake rates. Apparent digestibility of dry matter, organic matter, and neutral-detergent fiber was 10-20% higher for mountain goats and mountain sheep than for the other species (P < 0.04). Although these findings suggest a superior digestive efficiency for mountain goats and mountain sheep, species comparisons are inconclusive because of the confounding effects of season and ambient temperature on voluntary intake and digestion. Under the conditions of this experiment, the diet tested was safe, nutritious, and highly palatable. Protein and energy concentrations appear to be sufficient to meet or exceed known nutritional requirements of captive wild ruminants.

Animal Feed↗
PubMed2004

Production and characterization of monoclonal antibodies to peste des petits ruminants (PPR) virus.

Peste des petits ruminants (PPR) is an acute, febrile viral disease of small ruminants, caused by a virus of the genus Morbillivirus. PPR and rinderpest viruses are antigenically related and need to be differentiated serologically. In the present study, 23 mouse monoclonal antibodies were produced by polyethyleneglycol (PEG)-mediated fusion of sensitized lymphocytes and myeloma cells. Among these, two belong to the IgM class and the remaining 21 to various subclasses of IgG. The MAbs from the IgG class designated 4B6 and 4B11 neutralized PPR virus in vitro. In radioimmunoprecipitation assay, 10 MAbs recognized nucleoprotein, 4 recognized the matrix protein and one each haemagglutinin and phosphoprotein. The remaining 7 MAbs failed to precipitate any defined viral protein. The reactivity pattern of the monoclonal antibodies in indirect ELISA indicated a close antigenic relationship within three Indian PPR (lineage 4) virus isolates and also within two rinderpest vaccine strains. All PPR virus isolates could be distinguished from rinderpest vaccine viruses on the basis of the reactivity pattern of all MAbs and anti-N protein MAbs. A set of six monoclonal antibodies specific to PPR virus could also be identified from the panel. From the panel of MAbs available, two MAbs were selected for diagnostic applications, one each for the detection of antigens and antibodies to PPR virus.

Animals↗
PubMedDate not supplied

Structure and function in the ruminant synepitheliochorial placenta: central role of the trophoblast binucleate cell in deer.

The ruminant placenta has a very uniform gross structure based on localised areas of fetomaternal membrane apposition and proliferation to form placentomes. There is no consistency, however, in the number or size of these placentomes (6-150), nor in the villus architecture of the individual placentome. The one consistent feature is the binucleate cell (BNC) population in the trophoblast. These BNC form 15-20% of the epithelium in all ruminants examined so far. They synthesise the placental lactogen hormone and other glycoproteins and migrate through tight junctions to fuse with a uterine epithelial cell to form initially fetomaternal hybrid trinucleate cells (TNC) and subsequently syncytial plaques (SP). Such SP may be transient or persist throughout pregnancy depending on the species. The wide range of deer species examined confirms the uniformity of the BNC hormone production, migration, and fusion pattern described for other ruminants. BNC migration produces predominantly transient TNC, but there are areas of SP largely restricted to the apex of the maternal crypts. Maternal large granule lymphocytes (LGL) are uniquely found in deer placentomal uterine epithelium; they are usually closely associated with TNC and SP sites, but the significance of the interactions remains to be established.

Animals↗
PubMed1999

Evolution of ruminant Sarcocystis (Sporozoa) parasites based on small subunit rDNA sequences.

We present an evolutionary analysis of 13 species of Sarcocystis, including 4 newly sequenced species with ruminants as their intermediate host, based on complete small subunit rDNA sequences. Those species with ruminants as their intermediate host form a well-supported clade, and there are at least two major clades within this group, one containing those species forming microcysts and with dogs as their definitive host and the other containing those species forming macrocysts and with cats as their definitive host. Those species with nonruminants as their intermediate host form the paraphyletic sister group to these clades. Most of the species have considerable genotypic differences (differing in more than 100 nucleotide positions), except for S. buffalonis and S. hirsuta. There is a large suite of genotypic differences indicating that those species infecting ruminant and nonruminant hosts have had very different evolutionary histories, and similarly for the felid- and canid-infecting species. Furthermore, the rDNA sequences that represent the different structural regions of the rRNA molecule have very different genotypic behavior within Sarcocystis. The evolution of these regions should be functionally constrained, and their differences can be explained in terms of the importance of the nucleotide sequences to their functions.

Animals↗
PubMed2002

Differential receptor usage of small ruminant lentiviruses in ovine and caprine cells: host range but not cytopathic phenotype is determined by receptor usage.

The ovine maedi-visna (MVV) and caprine arthritis-encephalitis (CAEV) small ruminant lentiviruses (SRLV) exhibit differential species tropism and cytopathic effects in vitro. Icelandic MVV-K1514 is a lytic SRLV which can infect cells from many species in addition to ruminants, whereas a lytic North American MVV strain (85/34) as well as nonlytic MVV strain S93 and CAEV can infect only ruminant cells. In the present study, we determined if differential receptor usage in sheep and goat cells is the basis of differential species tropism or cytopathic phenotype of SRLV. Infection interference assays in sheep and goat synovial membrane cells using pseudotyped CAEV vectors showed that North American MVV strains 85/34 and S93 and CAEV use a common receptor (SRLV receptor A), whereas MVV-K1514 uses a different receptor (SRLV receptor B). In addition, human 293T cells expressing CAEV but not MVV-K1514 envelope glycoproteins fused with a goat cell line persistently infected with MVV-K1514, indicating that MVV-K1514 does not use SRLV receptor A for cell-to-cell fusion. Therefore, our results indicate that the differential species tropism of SRLV is determined by receptor usage. However, receptor usage is unrelated to cytopathic phenotype.

Animals↗
PubMed1977

Protected proteins in ruminant nutrition. In vitro evaluation of casein derivatives.

Chemical treatment of proteins in feeds can, by crosslinking protein chains or other chemical effects, decrease their solubility and microbial degradation in the rumen. A need exists to modify proteins systematically under well-defined conditions with inexpensive reagents and to evaluate the treated products nutritionally for possible beneficial effects on wool growth and quality as well as production of meat and milk. As a first step toward this goal we evaluated many derivatives of casein treated at pH 9-10 with various acylating and alkylating agents. Initial tests indicate that all treatments decreased protein digestion by rumen microorganisms. Potentially crosslinking reagents are usually more effective than similar ones that cannot crosslink. A few treatments gave ruminal protection that approached or exceeded that obtained with formaldehyde. This result shows that systematic evaluation of ruminal in vitro digestibility of protein derivatives may disclose new products deserving tests of post-ruminal digestibility and practical nutritive value.

Amino Acids↗
PubMed1996

Absorption of short-chain fatty acids across ruminal epithelium of sheep.

Investigations on the absorption of shortchain fatty acids across ruminal epithelium of sheep were performed both in vitro (Ussing chamber technique, using propionic acid representatively for short-chain fatty acids) and in vivo (washed, isolated reticulorumen). A pH-induced, nearly tenfold increase in the concentration of undissociated propionate led to an only twofold increase in mucosal-to-serosal flux of propionate (in vitro). Neither amiloride (1 mmol.l-1, in vitro) nor theophylline (10 mmol.l-1, in vivo), inhibitors of the ruminal Na+/H+ exchanger, exerted any significant influence on propionate fluxes or short-chain fatty acids absorption, respectively. Total replacement of luminal Na+ (by choline) did not alter short-chain fatty acids absorption (in vivo). Mucosal 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (0.1 mmol.l-1) or mucosal nitrate (40 mmol.l-1) markedly reduced propionate net flux (in vitro). Increasing mucosal Cl- concentration brought about a significant drop in mucosal-to-serosal flux of propionate (in vitro) and in short-chain fatty acids net absorption (in vivo), respectively. The results obtained suggest that short-chain fatty acids are absorbed both as anions and as undissociated acids across ruminal epithelium of sheep. It is concluded that short-chain fatty acids anions either compete with Cl- for binding sites at a common anion-exchange mechanism or that they are absorbed by an short-chain fatty acids anion/ HCO3- exchanger indirectly coupled to a Cl-/HCO3- exchanger via intracellular bicarbonate.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1990

Effects of Pasteurella haemolytica leukotoxin on neutrophils from white-tailed deer and several exotic ruminant species.

Pasteurella haemolytica leukotoxin is a pore-forming cytolysin which acts as a virulence factor in pasteurellosis of domestic ruminants. Leukocytes from cattle, sheep and goats are susceptible to leukotoxin-induced lysis; however, leukocytes from non-ruminant species so far tested are resistant to leukotoxin-induced lysis. Neutrophils obtained from three white-tailed deer, four Saiga antelope, an Addra gazelle, a Grant's gazelle and a Sable antelope were tested for susceptibility to the lytic effects of P. haemolytica leukotoxin using lactate dehydrogenase release. Results were compared to those obtained using neutrophils from a steer and cultured bovine lymphoma cells. Neutrophils obtained from all these ruminants, except the Addra gazelle, were susceptible to P. haemolytica leukotoxin. Individual variation among the Saiga and the deer did not appear to be due to the percentages of neutrophils or the percentage of contaminating erythrocytes in the cell preparations.

Animals↗
PubMed1990

Factors influencing the adherence of strains of Streptococcus bovis and Escherichia coli isolated from ruminal epithelium.

Two strains of Streptococcus bovis (A1 and A5) and one strain of Escherichia coli (0141:H28) isolated from the surface of bovine ruminal mucous epithelium were examined for adherence to isolated and cultured ruminal epithelial cells. The E. coli adhered to the target cell by means of fimbriae, which had several common properties with type 1 common fimbriae and caused mannose-sensitive haemagglutination. The A1 strain of S. bovis was devoid of fimbriae and its adherence to the epithelial surface was not inhibited by treatment with sugars or phenol-treated bacterial membrane from the same organism. It was therefore postulated that the bacterial glycocalyx of the S. bovis organisms acted as ligand. The extent of bacterial adherence depended on the state of differentiation of the target cell in both the isolated and the cultured ruminal cell systems. The receptors for both adherent bacterial species were in all probability associated with the glycocalyx of the target cells.

Animals↗
PubMed1976

Effect of oxygen saturation on H+ and Cl- distribution across the red cell membrane in human and ruminant blood.

Alterations of red cell pH (pHc) and distribution ratios of H+ (gammaH+) and Cl (gammaCl-) between plasma and red blood cells with oxygenation of blood were studied in human blood (audult and fetal) and ruminant blood (bovine, goat and sheep). The experiments were carried out at a plasma pH of 7.0 to 7.7 and at 37 degrees C. In human blood pHc of fully oxygenated blood was 0.035 pH lower than that of fully deoxygenated blood in all ranges of plasma pH studied. In ruminant blood, however, the differences in pHc between oxygenated and deoxygenated blood were 0.011 in ox, and 0.003 in goat and sheep, all of them not being significant. The decreases in gammaH+ accompanying oxygenation were in fairly good agreement with those in gammaCl- in human blood and amounted to about 0.05. In ruminant blood, in spite of virtually zero changes in gammaH+ with oxygenation, the decreases in gammaCl- were slightly greater than those in human blood. There might be a species difference in the mechanisms of distribution of Cl- and H+ across the red cell membrane.

Animals↗
PubMed1984

An automated micro-method for the enzymatic determination of D-B-hydroxybutyrate in ruminant plasma.

An enzymatic 'reaction rate' micro-method for the rapid routine estimation of D-B-hydroxybutyrate (D-B- HOB ) in ruminant plasma, using an I.L. Multistat III centrifugal analyzer, is described. Reaction conditions were optimized to give a linear response for plasma D-B- HOB concentrations between 100 and 2500 mumoles per litre, at 30 degrees C and pH 9.0. For the standardized method the within-run and between-run coefficients of variation for deproteinised ovine plasma were consistently less than 3.5%. There was good agreement between plasma concentrations obtained by the present method and both original U.V. end-point technique (r = 0. 927b = 0.950) and a colorimetric end-point procedure (r = 0.937. b = 0.879). Untreated ovine and bovine plasma consistently exhibited high 'blank' activity and this was directly correlated with plasma lactate dehydrogenase (LDH) activity in both species (r = 0.971; p less than 0.001 and r = 0.949; p less than 0.001 respectively). The distribution of LDH activity in man was similar to sheep but, contrastingly , non-specific interference was extremely low in human plasma and unrelated to LDH. Horse, chicken and rat had negligible 'blank' activity and comparatively low LDH levels. In both cattle and sheep non-specific interference was abolished by perchloric acid precipitation. In the sheep subtraction of 'blank' activity gave D-B- HOB concentrations for untreated plasma comparable to those in deproteinised samples. However, in the bovine, D-B- HOB levels remained significantly (t = 6.44; p less than 0.001) higher even after 'blank' correction. In contrast to man and other non-ruminants, perchloric acid precipitation is essential in ruminants to avoid false overestimation of plasma D-B- HOB levels. Plasma with EDTA as anticoagulant and serum gave concentrations of D-B- HOB approximately 60% lower, than samples containing heparin or oxalate/fluoride. However, heparin was associated with much higher (up to 50%) non-specific NAD reduction than oxalate/fluoride. High levels of acetoacetate (400-1000 mumoles per litre) reduced the recovery of D-B- HOB from ovine plasma by less than 10%. This effect was negated by the inclusion of hydrazine hydrate in the reaction mixture. Perchlorate ion concentrations above 25 mumoles per litre per test dramatically inhibited the assay in ovine plasma, and therefore precipitation conditions must be carefully controlled. Plasma with oxalate/fluoride as anticoagulant showed the greatest stability in storage; 24 hours at room temperature, one week at +4 degrees C and at least one month at -20 degrees C.

3-Hydroxybutyric Acid↗
PubMed1993

Rumination: the eating disorder of infancy.

Rumination is a relatively rare, potentially fatal syndrome in infants. This article reviews the historical and current treatment of rumination. Two cases are presented: a six-month-old who narrowly escaped surgery when the disorder was not recognized, and a complicated case from the neonatology intensive care unit. Environmental changes and enhanced mothering are described as being critical to correction of rumination and appropriate weight gain.

Developmental Disabilities↗
PubMed2004

GATC-specific restriction--modification systems in ruminal bacteria.

The GATC-specific restriction and modification activities were analyzed in 11 major bacterial representatives of ruminal microflora. Modification phenotype was observed in 13 out of 40 ruminal strains. MboI isoschizomeric restriction endonucleases were detected in 10 bacterial strains tested; three strains lacked any detectable corresponding endonuclease activity. The only examined strain of Mitsuokella multi-acida was found to possess a different type of endonuclease activity. This is the first report on restriction activity in ruminal treponemes M. multiacida and Megasphaera elsdenii.

Animals↗