Biomedical subjects

P Y Hester

Publications and source records attributed to P Y Hester.

60 records · Page 4Linked to original sources

PubMed1981

The effect of caponization and dietary 17 alpha-methyltestosterone on the incidence of leg abnormalities in turkeys.

Six hundred and seventy-two male turkeys were raised according to standard management procedures from 1 day to 3.5 weeks of age. At 3.5 weeks of age, the poults were equally distributed among four treatment groups. One group was subjected to surgical caponization and a second to sham operations. Of the two remaining groups, one served as a control while the other received feed containing 110 ppm of 17 alpha-methyltestosterone. All birds were maintained under identical environmental conditions until 20 weeks of age. Capons demonstrated a significantly higher incidence of leg abnormalities than controls or testosterone fed birds but did not differ significantly from the shams. These data correlated well with the levels of plasma androgen in that capons had significantly lower levels of plasma androgen than controls or testosterone fed turkeys, but concentrations did not differ significantly from shams. Plasma androgen concentrations or percentages of leg abnormalities were not different among shams, controls, or testosterone fed birds. Body weights, feed/gain ratios, mortality, and plasma corticosterone were similar for all four treatment groups.

Androgens↗

PubMed1980

Effect of mercury toxicity on serum osmolality, plasma sodium and potassium, and serum proteins in the chicken.

Juvenile male chickens were exposed continuously to 300 micrograms/ml of mercury (Hg) in the form of mercuric chloride (HgCl2), via the drinking water, from hatching through six weeks of age. Serum osmolality and plasma potassium were increased significantly as a result of the Hg treatment. Plasma sodium was increased numerically in two of the three trials. Of the serum proteins, only albumin and the transferrins exhibited a consistent significant increase. It is concluded that alterations in serum ions and proteins account for the significant increase in plasma osmolality. The increase in transferrins may represent a mechanism to bind and detoxify Hg.

Animals↗

PubMed1978

The excretory system of young chickens experiencing mercury toxicity--effects on kidney development, morphology, and function.

Four trials were conducted to determine if toxic levels of mercury affect kidney development, morphology, and renal function. Mercury, administered via the drinking water as mercuric chloride caused a reduction in gross kidney weight, an increase in relative kidney weight and a slight but significant increase in the percentage water retained by left kidney of 6-week-old cockerels. Mercury had no effect on renal function of 6-week-old birds as indicated by the clearance of phenol red from circulation. Histological discontinuity of the kidney was extensive and evidenced by foamy cell degeneration and nuclear pyknosis. Although mercury caused gross alterations in the morphology of the kidney, normal excretory function was maintained.

Animals↗

PubMed1977

Mercury induced cardiovascular abnormalities in the chicken.

Juvenile chickens were either chronically exposed to 300 microgram/ml of Hg in the drinking water (chronic dosage--CD) or acutely exposed to either 3 mg of Hg/kg body wt (acute low dosage--ALD) or 12 mg of Hg/kg body wt (acute high dosage--AHD) administered intramuscularly for five consecutive days. Only the CD and AHD treatments retarded normal growth. Relative heart weights were increased by the CD treatment, decreased by the AHD treatment, and remained unchanged during the ALD treatment. Relative aorta weights were increased by the CD treatment but decreased by the AHD treatment. ECG analyses revealed a consistent decrease in the amplitude of the R-S and T waves with the greatest effects present in the acute (ALD and AHD) treatments. Histological examination revealed that Hg caused myocardial histopathological changes characterized as a myocarditis with polymorphonuclear and lymphocytic infiltration and fatty degeneration. It is concluded tha Hg causes cardiovascular disturbances in chickens even when administered at levels which do not inhibit normal growth.

Animals↗

PubMed1977

Immunosuppression in chickens by passive transfer of preparations of specific immunoglobulins.

The immunosuppressive effects of passive transfers of specific immunoglobulin preparations obtained from immune or hyperimmune sera were evaluated in chickens which were challenged with sheep red blood cells. The data indicate that IgY, fractionated from immune sera, and IgY and IgM, fractionated from hyperimmune sera, when passively administered at the doses employed in this study resulted in antibody-mediated suppression.

Animals↗

PubMedDate not supplied

Effect of spectinomycin on Escherichia coli infection in 1-day-old ducklings.

Two challenge trials and one confirmation trial were conducted to evaluate the efficacy of spectinomycin in the treatment of 1-day-old ducklings infected with Escherichia coli. In the challenge trials, ducklings were injected in the right posterior thoracic air sac with 0.2 cm3 of broth containing 10(8) colony-forming units E. coli (strain O78, E38)/ml. Spectinomycin at dosage levels of 2.5 mg, 5.0 mg, and 10.0 mg of activity was injected subcutaneously 6 hours following infection. The confirmation trial was conducted to confirm the challenge trials; procedures were similar to those used in the challenge trials, except that only the 5.0 mg of activity dosage of spectinomycin was used. In both types of trials, spectinomycin-treated ducklings had significantly lower mortality and higher average weight gain, average daily gain, and feed consumption than infected unmedicated controls. These results indicate that spectinomycin is effective in treating ducks for experimentally induced colibacillosis caused by E. coli (strain O78, E38).

Animals↗