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Biomedical subjects

W B Buck

Publications and source records attributed to W B Buck.

At least 91 records · Page 5Linked to original sources
PubMed1980

Increased susceptibility of lead-exposed swine to Salmonella choleraesuis var kunzendorf.

The effect of oral subclinical lead exposure on the susceptibility of swine to Salmonella choleraesuis var kunzendorf was studied in two experiments. In experiment 1, 18 pigs were exposed to lead acetate and 18 pigs were exposed to sodium acetate for 1, 2, or 3 weeks and then challenge exposed intraperitoneally. In experiment 2, 8 pigs were exposed to lead chloride for 2 weeks, 8 pigs were exposed to lead chloride for 1 week, and 8 pigs were exposed to sodium chloride for 2 weeks. These pigs were then challenge exposed orally. Only one pig (sodium acetate-exposed) died during experiment 1, but clinical signs were more severe in sodium acetate-exposed than in lead acetate-exposed animals. In experiment 2, 93.6% of the lead-exposed pigs died, whereas control pigs had 50.0% mortality. In experiment 2, clinical signs were more severe in lead-exposed pigs, and bacteria were more widespread in the tissues of these animals. Significant reductions of beta- or gamma-globulin concentrations or of agglutinating antibody titers were not observed in lead-exposed pigs in either of the trials. Possible mechanisms of the increased susceptibility in lead-exposed pigs of experiment 2 are discussed.

Animals↗
PubMed1979

Equine leucoencephalomalacia (ELEM): a study of Fusarium moniliforme as an etiologic agent.

Signs and lesions characteristic of equine leucoencephalomalacia were produced in one of two donkeys given corn cultured with Fusarium moniliforme Sheldon. Gross and histopathologic lesions of the cerebrum included an extensive necrotic cavitation within one cerebral hemisphere, disruption and rarefication of the subcortical white matter, prominent perivascular hemorrhage, and some mononuclear cell perivascular cuffing. Another donkey and three rabbits fed the cultured corn did not develop characteristic signs or lesions of the toxicosis. Chick bioassay studies indicated that the cultured corn which produced the disease did not contain a monovalent salt of moniliformin.

Animals↗
PubMed1979

Experimental lead toxicosis in swine.

Thirty pigs, weighing 17 to 24 kg, were exposed to lead or sodium acetate orally or intraperitoneally (IP) 6 days each week for 13 weeks. These pigs were extremely tolerant of lead. Only mild clinical signs of lead toxicosis were observed in orally lead-exposed pigs despite blood lead concentrations of up to 290 micrograms/dl. Four IP lead-exposed pigs died, but eight other IP lead-exposed pigs survived the exposure period despite blood lead concentrations up to 14,300 micrograms/dl. Lead exposure caused marked decreases in blood delta-aminolevulinic acid dehydratase activities of all pigs and moderate decreases of blood hemoglobin concentrations, hematocrit percentages, mean corpuscular volumes, mean corpuscular hemoglobin concentrations, and mean corpuscular hemoglobins in IP lead-exposed, but not in orally lead-exposed pigs. Basophilic stippling was observed in erythrocytes of lead-exposed pigs, but not in those of control pigs.

Administration, Oral↗
PubMed1979

Animals as monitors of environmental quality.

The various species of domesticated and wild animals can be excellent monitors of environmental quality. Although analyses of industrial air and water effluents and tests for toxicants in soils, plants, foods and feeds may provide some degree of predictability of environmental quality, the ultimate monitors are those organisms having metabolic activities that are comparable to man. If we closely observe animals that share our environment, like the coal miner's canary, they will alert us to unseen and perhaps devastating environmental hazards.

Animal Diseases↗
PubMed1975

Clinical infectious bovine rhinotracheitis in cattle fed organic iodine and urea.

The feeding of ethylenediamine dihydriodide (EDDI) at the dose levels of 50 and 500 mg/animal/day and urea at the dose level of 45 g/animal/day did not affect duration of clinical signs, body weight gain, magnitude or duration of fever, serum concentration of glutamic oxalacetic transaminase, packed cell volume, and differential white blood cell counts in feeder cattle experimentally infected with infectious bovine rhinotracheitis (IBR) virus. However, coughing and abundance of nasal discharge were significantly greater in calves fed EDDI before and during primary IBR virus infection. Those calves fed 500 mg of EDDI/day coughed more, had greater nasal discharge, and exhibited greater lacrimation than did those given the smaller dose. These 3 clinical signs were considered to reflect both the expectorant action of EDDI and the pathogenic effects of IBR virus. In all calves, including controls, the coughing, nasal discharge, and lacrimation were most prominent during the period of peak infection (7 to 14 days after the calves were given intranasal inoculation) of the IBR virus. Total serum iodine concentration became maximal (mean of 1,400 ng/ml) in 8 calves after they had been fed the larger dose of EDDI for 2 weeks. This value was maximal (about 300 ng/ml) in another 8 calves after 3 weeks' feeding of the smaller dose (50 mg/day). When EDDI exposure was maintained at the dose level of 50 mg/day for 5 weeks longer, mean serum iodine values remained at about 275 ng/ml, and those of control calves averaged 140 ng/ml.

Ammonia↗
PubMed1974

Development of behavioral tests for the assessment of neurologic effects of lead in sheep.

Reports of neurologic impairment of children following recovery from acute lead encephalopathy have raised questions concerning the effects of chronic low-level lead exposure on the central nervous system. Behavioral toxicologic techniques have been employed to assess the effects of lead on the central nervous system in sheep. Mature sheep receiving daily doses of 100 mg lead/kg showed a significant decrease in performance on an auditory signal detection task. Daily oral doses of 120 and 230 mg lead/sheep for 27 weeks did not alter the performance of mature sheep on a fixed-interval schedule of reinforcement behavioral task. Prenatal exposure to maternal blood lead levels of 16 or 34 mug/100 ml during gestation and postnatal daily ingestion of 16, 8, 4, or 2 mg lead/kg did not alter performance of lambs on a closed-field maze task. Slowed learning was demonstrated in lambs prenatally exposed to maternal blood lead levels of 34 mug/100 ml during gestation when tested on nonspatial, two-choice visual discrimination problems at 10-15 months of age.

Administration, Oral↗