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At least 37 records · Page 2Linked to original sources
PubMed1977

Acute myopathy in outwintered cattle.

An outbreak of acute myopathy occurred in a group of 23 Hereford cross and Aberdeen Angus cross 18-month-old heifers, running outside with a bull in February. One morning two were found recumbent, five were ataxic and one had fallen into a river and drowned. Subsequently two of the ataxic ones became recumbent. Serum creatine phosphokinase values were found to be directly proportional to the severity of the clinical manifestations. Myoglobinuria was not observed. Serum calcium, magnesium and inorganic phosphate levels were all within the normal ranges. Treatment of affected animals with selenium and/or alpha-tocopherol had no clear effect; from biochemical estimations carried out, the selenium and alpha-tocopherol status of both affected and unaffected animals was considered adequate. Five recovered, two spontaneously without treatment, but the two most severely affected did not improve with therapy and had to be slaughtered 13 and 25 days respectively after the onset of symptoms.

Animal Feed↗
PubMed1978

Kinetics of in vitro bovine lymphocyte immunostimulation with a Brucella abortus antigen.

A Brucella abortus-soluble antigen was investigated, using in vitro assay of lymphocyte immunostimulation, to determine which concentration of this antigen and which period of incubation of the lymphocyte cultures would induce maximum specific lymphocyte immunostimulation as an additional method for further study of B abortus infection in cattle. Soluble antigen was prepared from autoclaved cells of B abortus strain 1119-3. Peripheral blood lymphocytes were obtained from cattle infected with B abortus and from healthy control cattle not infected with B abortus. The lymphocytes were prepared by the Ficoll-Hypaque density gradient technique, suspended in RPMI 1640 medium (1.5 X 10(6)/ml), cultured with several dilutions of soluble antigen, and incubated. Prior to termination of incubation, cultures were labeled with 1 muCi of [3H]thymidine and, after harvesting, assayed for [3H]thymidine incorporation in DNA by a liquid scintillation spectrometer. Maximum specific immunostimulation of lymphocytes from B abortus-infected cattle was induced in this assay system with 6 days' incubation and 22 microgram of protein/ml/1.5 X 10(6) lymphocytes, using protein content to express concentration of soluble antigen in this system.

Animals↗
PubMed1978

Specific lymphocyte stimulation in cattle naturally infected with strains of Brucella abortus and cattle vaccinated with Brucella abortus strain 19.

Cell-mediated immune responses in cattle naturally infected with strains of Brucella abortus and in cattle vaccinated with B abortus strain 19 during calfhood were studied by an in vitro lymphocyte-stimulation procedure. Lymphocytes were prepared from peripheral bovine blood by the Ficoll-diatrizoate technique, suspended in RPMI-1640 medium (1.5 X 10(6) lymphocytes/ml), cultured with B abortus-soluble antigen or phytohemagglutinin, and incubated for 6 days. Sixteen hours prior to termination of incubation, cultures were labeled with 1 muCi of [3H]thymidine (3HdT) and, after harvesting, assayed for 3HdT incorporation into DNA by liquid scintillation spectrometry. Lymphocytes from cattle with bacteriologically confirmed isolation of B abortus underwent a significantly higher lymphocyte stimulation with B abortus-soluble antigen than did cattle vaccinated with B abortus strain 19 during calfhood (P less than 0.005). Standard seroagglutination tests were conducted simultaneously with lymphocyte-stimulation tests, but there was no apparent correlation between levels of humoral antibodies and the cell-mediated immune responses as measured by in vitro specific lymphocyte stimulation.

Agglutination Tests↗
PubMed1978

Whole-blood lymphocyte stimulation assay for measurement of cell-mediated immune responses in bovine brucellosis.

A study was conducted to develop an in vitro whole-blood lymphocyte stimulation assay for measurement of cell-mediated immune response in bovine brucellosis. A soluble antigen (BASA) prepared from killed cells of Brucella abortus 1119-3 was used. Cattle infected with B. abortus field strains, B. abortus 19 calfhood- and adult-vaccinated cattle, and nonexposed cattle were tested. Blood was diluted 10-fold in RPMI-1640 medium (without added serum) and cultured with BASA (at a concentration of 2.2 microgram per culture) at varying times of incubation. Results were assayed for [3H]thymidine incorporation into deoxyribonucleic acid. A 6-day period was found to be optimal for incubating blood cultures to achieve maximum specific lymphocyte stimulation. Serological tests and bacteriological isolation attempts were conducted simultaneously with lymphocyte stimulation tests, and there was a significant correlation between cell-mediated immune response and bacteriological findings. There was a significant correlation between cell-mediated immune response and the level of serum antibodies on a group basis, but there was little correlation between the two systems on individual infected animals. Among vaccinated animals there was little or no correlation between cell-mediated immune and humoral responses. The whole-blood assay was found to be simple, fast, sensitive, and reproducible.

Animals↗
PubMed1977

Physiological and endrocine parameters in beef cattle: breed, sex and year differences.

Plasma corticoids, potassium and sodium, thyroid activity and hemoglobin and hematocrit values were determined at slaughter over a period of four years in 1612 animals representing the following sire groups: Short-horn, Charolais, Simmental, Limousin, Red Angus, Beefmaster, Brown Swiss, Chianina and Jersey. Differences among years and among breeds of sire were significant for all the parameters studied. Hematocrit values were the highest in females and the lowest for entire males, while hemoglobin levels were the lowest in females and the highest for bulls. Plasma corticoid levels were lower for entire males as compared to steers and heifers. Plasma sodium and potassium levels were the highest for females and the lowest entire males. The values reported in this study for several blood components, based on a large number of animals, could serve as clinical guides and as a basis for further research.

Animals↗
PubMed1977

Characterization and substrate specificity of fumarylacetoacetate fumarylhydrolase.

The molecular weight of fumarylacetoacetate fumarylhydrolase (EC 3.7.1.2) is 86 000 +/- 10 000, as determined by gel filtration. The enzyme appears to be a dimer with a monomer molecular weight of 38 000 - 43 000, as determined by gel electrophoresis, gel filtration in guanidine-hydrochloride, and ultracentrifugation. The subunits appear to be identical, as only one band is seen in gel electrophoresis, only one protein peak is detected in gel filtration in guanidine-hydrochloride, and only one amino-terminal amino acid (proline) is detected. Three free sulfhydryl groups per denatured monomer are detected by reaction with 5,5'-dithiobis(2-nitrobenzoic acid), while for the active enzyme only two sulfhydryl groups react with this reagent, The extinction coefficients at 260 and 280 nm, the amino acid composition, and the isoelectric point (6.7) of the enzyme are also reported. The enzyme catalyzes the hydrolysis of six 2,4-diketo acids and three 3,5-diketo acids tested. The Km of the substrates is similar but V varies by a factor of 120. The pH optimum is 7.3. The enzyme did not catalyze the hydrolysis of a number of esters tested.

Acetoacetates↗
PubMed1979

Temporal cell-mediated immune responses of cattle following experimental and natural exposure to living Brucella abortus.

A study on cell-mediated immune responses in cattle with different exposure experiences to Brucella abortus was conducted by an in vitro lymphocyte stimulation assay. The purpose of this study was to determine how soon the cell-mediated immune responses would be detected following experimental exposure to B. abortus and to study the cell-mediated immune trend following experimental and natural exposure of cattle to B. abortus. The first positive cell-mediated immune responses occurred one to two weeks after experimental inoculation with living B. abortus strain 2308. The cell-mediated immune responses in these animals appeared at least one week before the appearance of of B. abortus serum agglutinating antibodies. Animals which were naturally infected with B. abortus biotypes 1 and 2 demonstrated positive cell-mediated immune responses throughout the study.

Animals↗
PubMed1976

The nature of the residual alpha-mannosidase in plasma in bovine mannosidosis.

Acidic alpha-mannosidase (EC 3.2.1.24), optimum pH 4.25, is absent from the plasma of Angus calves with mannosidosis, and the residual alpha-mannosidase activity has an optimum pH of 5.5, intermediate between that of the acidic and neutral alpha-mannosidases. This 'intermediate' alpha-mannosidase differs from the acidic form in its kinetic properties, its lack of marked inhibition by EDTA and its thermolability at 55 degrees C and physiological pH. Isoelectric focusing and ion-exchange chromatography show that it exists in at least two forms. The presence of a secondary peak at pH 5.5 in the pH/activity profile of normal plasma and the effect of heating at 55 degrees C indicate that such a form is present in normal plasma. The residual activity in the plasma of a calf with mannosidosis is therefore probably not the product of the defective gene. A differential assay, based on their different stabilities at 55 degrees C, has been developed for measuring the acidic and intermediate alpha-mannosidases in plasma. There was no correlation between the concentrations of the two enzymes in the plasma of Angus cows heterozygous for mannosidosis or in the plasma of normal animals. This precludes the use of the intermediate form as a reference enzyme for the acidic activity in a test for heterozygosity for mannosidosis based on the gene-dosage phenomenon. The concentrations of the intermediate activity were comparable in normal animals and animals homozygous or heterozygous for mannosidosis.

Animals↗