Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2006
Publication Date: 12/3/2006
Citation: Purdy, C.W., Straus, D., Norman, R. 2006. RIA analysis for estradiol, testosterone and cortisol in feedyard playa lakes and non-feedyard playa lakes [abstract]. In: Proceedings of the 87th Annual Meeting of the Conference of Research Workers in Animal Disease, December 3-5, 2006, Chicago, Illinois. p.150.
Technical Abstract: The objective of the study was to compare the levels of 17B-estradiol, testosterone, and cortisol hormones in bottom sediment (muck) and water of seven feedyard (FY) playas and three non-feedyard playas. Four liters of water and 500 grams of muck were collected from 4 equal distant sites from each playa shallow lake. The water was freeze-dried. The water residue and the muck were extracted with ether and analyzed for hormones by specific radioimmunoassays. The hormone mean concentrations are reported in ng/g of muck and ng/100 ml of water. Statistical analysis was done by Proc GLM and Dunnett’s paired t-analysis. Differences were considered significant at P < 0.05. The mean hormone concentrations of the three non-feedyard playas were averaged and compared to each of the seven feedyard playas. The mean concentrations of the three hormones for all seven feedyard playas were larger than the mean concentration of the 3 non-feedyard playas [muck: estradiol, 0.45 (Standard Error 0.04), testosterone, 0.43 (0.01) and cortisol, 0.12 (0.03), water: estradiol, 0.56 (0.13), testosterone, 0.33 (0.18) and cortisol, 0.53 (0.27)]. In the muck: Estradiol was significantly larger in FY3, 8.14 (2.63), & FY11, 10.8 (1.32); cortisol was larger in Fy2, 7.1 (4.09); and testosterone was larger in FY3, 8, & 11, ranged from 3.7 (0.49) to 10.7 (1.43). In the water: Estradiol was significantly larger in FY5, 7, 8, and 11, ranged from 12.65 (3.17) to 60.56 (7.47); cortisol was larger in FY3, 17.25 (1.7) and FY11, 7.25 (0.47); testosterone was significantly larger in FY3, 5, 7, 8, and 11, ranged from 27.8 (7.6) to 48.6 (11.6). The significance of these hormone concentrations in wastewater on wildlife is unknown and their effect on calves sprayed to settle the dust in calf pens is also unknown.