Phagocytic acitivity of bovine leukocytes during pregnancy.
(9/174666)
The phagocytic competence, measured as the total number of polymorphonuclear leukocytes per mm3 which phagocytosed Staphylococcus aureus, strain 321, in vitro, was determined in eight cows during complete pregnancies. Such leukocytes are referred to as "Active PMN'S". There was a gradual decline in the number of these cells from conception to a minimum between the 16th and 20th weeks of pregnancy, followed by a steady increase to the cessation of lactation when a marked drop occurred, after which there was an increase to a maximun during the second week prepartum. From this maximum there was a rapid decrease to an absolute minimum during the first week after parturition. From the second week postpartum there was a gradual increase to conception. The correlation coefficient (r) of number of active PMN'S with time before conception was -0.474 )p-0.01). There were significant differences (p=0.01) in numbers of active PMNS Among the eight cows. It was found that the cows fell into two groups, one whose members had, overall, significantly more active PMNs (p=0.001) than those in the second group. The between cow differences may have been due to 1) age, since the cows with the highest numbers of circulating active PMNs were younger than those in the other group of 2) the combined stress of pregnancy and lactation, as those cows which were both pregnant and milking had the lowest numbers of active PMNs. (+info)
Mercury and Mink. II. Experimental methyl mercury intoxication.
(10/174666)
Adult female mink were fed rations containing 1.1, 1.8, 4.8, 8.3 and 15.0 ppm mercury as methyl mercury chloride over a 93 day period. Histopathological evidence of injury was present in all groups. Mink fed rations containing 1.8 to 15.0 ppm mercury developed clinical intoxication within the experimental period. The rapidity of onset of clinical intoxication was directly related to the mercury content of the ration. Mercury concentration in tissue of mink which died were similar, despite differences in mercury content of the diets and time of death. The average mercury concentration in the brain of mink which died was 11.9 ppm. The lesions of methyl mercury poisoning are described and criteria for diagnosis are discussed. (+info)
Effect of trauma on plasma glucagon and insulin concentrations in sheep.
(11/174666)
Portal plasma glucagon and insulin concentrations were measured before and after acute trauma (liver biosy). The trauma was sufficient to increase glucagon concentrations and depress insulin concentrations. These changes were associated with a marked hyperglycemia. Infusion of glucagon was insufficient to prevent stress inhibition of insulin secretion. The stimulation of glucagon secretion and inhibition of insulin secretion were of about one hour duration. These findings indicate that glucagon and insulin in conjunction with the nervous system may play an important role in the development of stress related hyperglycemia. (+info)
Infleuce of dietary levels of vitamin E and selenium on tissue and blood parameters in pigs.
(12/174666)
Eighteen barrows approximately three weeks of age were used in a 3 X 3 factorial arrangement to investigate the effect of level of supplemental vitamin E and selenium on tissue and blood parameters. Tissue selenium concentrations increased in a quadratic manner with increased selenium intake with kidney tissue containing considerably greater concentrations than liver, heart or muscle. Supplementation of the diet caused a three-fold increase in serum selenium within the first week with a slight tendency to further increases in subsequent weeks. Serum vitamin E of unsupplemented pigs declined by fifty percent during the experiment, whereas supplemental vitamin E resulted in increased serum vitamin E. There was a considerable viration in percent peroxide hemolysis. Correlation of -0.63 between percent peroxide hemolysis and vitamin E intake and -0.85 between percent peroxide hemolysis and serum vitamin E were observed. (+info)
The role of colorstrum on the occurrence of immunoglobulin G subclasses and antibody production in neonatal goats.
(13/174666)
Quantitative determinations of IgG1 and IgG2, in one group of colostrum-fed and one group of colostrum-deprived neonatal goats revealed that the occurrence of the IgG1 subclass preceeded that of the IgG2 in both cases. In the colostrum-fed animals the IgG2 appeared, on an average, in the fourth week of life whereas in the colostrum-deprived animals the IgG2 was detected as early as three weeks after birth. At the age of twelve weeks the mean concentrations for IgG, and IgG2 were higher in the animals deprived of colostrum. The immune response to human gamma globulin was studied in colostrum-fed and colostrum-deprived neonatal goats which were immunized at birth and again after four and eight weeks. Following the first two antigen administrations a significantly higher response was obtained in the colostrum-fed neonates. However, the third injection determined a similar response in both groups. A marked suppressive effect on the immune response was observed in colostrum-fed neonatal goats when specific antibodies were present in the colostrum after preimmunization of the mothers with human gamma globulin. (+info)
Strongyle infections in ponies. I. Response to intermittent thiabendazole treatments.
(14/174666)
A group of seven ponies naturally infected with large numbers of small strongyles and raised under conditions to minimize reinfection were treated periodically over a three year span with thiabendazole at the rate of 44 mg/kg body weight. Based on the absence of worm eggs in the feces following each treatment, thiabendazole removed the adult strongyles present with a new population subsequently developing by maturation of inhibited larvae. It took as many as four or five treatments to eliminate or reduce significantly the worm burdens present in the ponies under the conditions of this study. Strongyle eggs started to reappear in the feces about six weeks after treatment and following the first treatment the mean egg counts rose to the pretreatment level. On successive treatments the interval for worm eggs to appear in the feces lengthened and mean egg counts never rose quite as high as immediate pretreatment levels. Hematological changes were not marked, although a small steady increase in the mean hemoglobin values and an equivalent small decrease in the mean eosinophil counts occurred in all ponies following each successive treatment. The study supports the rationale of regular anthelmintic treatment of horses in that even in the absence of reinfection, new burdens of adult worms develop following treatment. (+info)
Strongyle infections in ponies. II. Reinfection of treated animals.
(15/174666)
Five of seven ponies whose strongyle worm burdens had previously been removed or markedly reduced by repeated thiabendazole treatments were reinfected with doses ranging from 100,000 to 500,000 small strongyle infective larvae. Reinfection of ponies resulted in the development of clinical signs characterized by abnormal feces, marked loss of weight and delayed shedding of winter hair coats. An abrupt increase in circulating eosinophils occurred during the first three weeks following reinfection. Patent infections developed in all ponies with worm eggs appearing in the feces from 12 to 15 weeks after receiving infective larvae. Worm egg outputs followed a cyclic pattern with approximately four to five peaks in egg output per year. There was an abrupt drop in the high worm egg counts in two untreated ponies approximately two and a half years after reinfection. No worms were recovered in the feces of these animals when they were subsequently treated, suggesting that a depletion in the number of inhibited larvae present in these ponies might have occurred. (+info)
Serum ampicillin levels in the calf: influence of dosage, route of administration and dosage form.
(16/174666)
Holstein bull calves received ampicillin sodium by the intravenous, intramuscular and subcutaneous routes and ampicillin trihydrate by the intramuscular route, at a dosage of 5 mg/kg. In addition ampicillin sodium and ampicillin trihydrate were given at a 12 mg/kg dosage intramuscularly. The serum ampicillin concentrations were determined at five, 30, 60, 120, 180, 240 and 300 min after drug administration and at 360 min after ampicillin trihydrate injection. Intravenous administration gave a high initial level (16.2 mug/ml) at five min that declined to below 1 mug/ml by 120 min. Subcutaneous administration produced the lowest initial levels of drug but concentrations of drug detected did not differ significantly from the intramuscular administration at any sampling interval. The 12 mg/kg intramuscular ampicillin sodium dosage produced significantly higher levels than the 5 mg/kg dosage only at five min. Ampicillin trihydrate gave higher levels than ampicillin sodium at all times except 30 min (5 mg/kg) and five min (12 mg/kg). The serum ampicillin disappearance study (5 mg/kg intravenous) gave a two component bi-exponential curve. Kinetic analysis of the first component showed a C01 (theoretical initial conc) of 44.8 mug/ml, a ke1 (rate constant of disappearance) of 0.064 mug min and a t1/21 (calculated half-life) of 10.8 min. The Co2, ke2 and t1/22 of the second component were 6.2 mug/ml, 0.0157 mug/min and 46.2 min respectively. (+info)