Authors : I.O. Adam , B.J. Rude , P.L. Ryan , D.L. Christiansen , N.M. Filipov , Veysel Akay , N.S. Hill and B.P. Fitzgerald
Abstract: Glucomannan modified for greater ergot alkaloid affinity was fed to mares to evaluate its efficacy as a dietary ergot alkaloid adsorbent. Mares were fed bermudagrass hay along with one of four feed mixtures containing either endophyte-free (E-) or toxic endophyte-infected tall fescue seed. All rations based on toxic endophyte-infected tall fescue seed contained 1.69 ppm ergot alkaloids on a dry matter (DM) basis. Modified GLMN was provided at 0 (E+), 5 (E+5), or 10 g (E+10) twice daily. Efficacy of ergot alkaloid adsorption by GLMN was evaluated by measuring alkaloid consumption vs. fecal and urine excretion. Blood metabolites and hormones were evaluated as physiological indicators of ergot elimination. Hay and total DM intake (DMI) was not affected (p = 0.59) and ranged from 1.17 to 1.33 and 2.0 to 2.15% BW/d, respectively. Ergot alkaloid concentrations in feces (p = 0.02; 31.02 to 225.53 ng g-1) and urine (p < 0.01; 0.96 to 37.12 ng mg-1 creatinine) were greater for mares receiving E+, E+5, or E+10 than E- and supplemental GLMN did not alter urinary ergot alkaloid excretion. No differences were found within treatment phase for plasma 3,4-dihydroxyphenylacetic acid (DOPAC; p = 0.24; 4.94 to 8.68 ng mL-1), serum cortisol (p = 0.14; 4.48 to 5.69 μg dL-1), or PRL (p = 0.40; 2.89 to 3.85 ng mL-1). Findings are inconclusive and further investigation is needed to determine the efficacy of feeding modified GLMN to mares grazing toxic endophyte-infected tall fescue pastures.
I.O. Adam , B.J. Rude , P.L. Ryan , D.L. Christiansen , N.M. Filipov , Veysel Akay , N.S. Hill and B.P. Fitzgerald , 2006. Glucomannan as a Dietary Ergot Alkaloid Adsorbent for Mares. Journal of Animal and Veterinary Advances, 5: 1242-1250.