The disposition and absorption kinetics of gentamicin were studied in healthy, mature male and female turkeys (n = 10). Single doses of gentamicin (5 mg/kg) were injected either i.v. or i.m. with a 30-day rest period between each treatment. Baseline and serial venous blood samples (n = 17) were collected from each turkey. Serum concentrations of gentamicin were determined in duplicate for 24 h after each treatment, using radio-immunoassay. Using nonlinear least-square regression methods, the combined data of the i.v. and i.m. treatments were best described by a two-compartment open model. Kinetic analysis of the data after a single i.v. dose provided the following mean values: t1/2 alpha = 0.170 +/- 0.093 h, t1/2 beta = 2.57 +/- 0.79 h, MRT = 3.62 +/- 0.96 h, Vc = 0.090 +/- 0.017 l/kg, Vd(ss) = 0.172 +/- 0.024 l/kg, Vd(area) = 0.190 +/- 0.030 l/kg, and Clt = 49.8 +/- 9.8 ml/h/kg. After a single i.m. dose, the following mean values were determined: MRT = 5.10 +/- 1.73 h, t1/2abs = 0.74 +/- 0.66 h, tlag = 0.07 +/- 0.19 h, Clt/F = 50.7 +/- 12.5 ml/h/kg, Vd(area)/F = 0.193 +/- 0.044 l/kg, and F = 102 +/- 21%. Kinetic calculations made with the single i.m. data predicted that an i.m. injection of gentamicin at the dosage rate of 3 mg/kg q. every 12 h would provide average steady state serum concentrations of 4.93 micrograms/ml.

fat by chicks. J. Agr. Sci. 40: 39^3. Duncan, D. B., 195S. Multiple range and multiple F tests. Biometrics, 11: 1-42. Essary, E. 0., 1961. The influence of added fat and protein in broiler rations on growth rate, dressing percentage, and other carcass characteristics. Thesis, unpublished. Michigan State University. Essary, E. O., L. E. Dawson, E. L. Wisman and C. E. Holmes, 1965. Influence of different levels of fat and protein in broiler rations on live weight, dressing percentage and specific gravity of carcasses. Poultry Sci 44: 304-305. Fraps, G. S., 1943. Relation of the protein, fat and energy of the ration to the composition of chickens. Poultry Sci. 22: 421-424. Harshaw, H. M., 1936. Effect of diet, range, and fattening on the physical and chemical composi-

METHODSThree strains of Broad White turkeys (strains A, B, and C) were used to develop the hypertensive and hypotensive blood 405 at

Venous blood samples were collected at 3-day intervals for a total of six samples from each of five adult male pekin ducks and five adult Ross roosters. Twenty biochemical, six hematologic, and three endocrine determinations were performed on each blood or serum sample collected. The data obtained provide reference values for future studies of avian species and illustrate the utility of an automated clinical chemistry analyzer in assessing multiple serum biochemistry values in small sample volumes obtained from birds.

Deficiencies in over-heated soybean oil meal. Poultry Sci. 26: 150-156. Fraenkel-Conrat, H., and M. Cooper, 1944. The use of dyes for the determination of acid and basic groups in proteins.