Investigation of the Toxic Affect of Manganese on Ruminal Microbial Digestion and Growth

Author

Erin Dearing, Utah State University

Date of Award

5-2005

Degree Type

Thesis

Degree Name

Departmental Honors

Department

Animal, Dairy, and Veterinary Sciences

Abstract

This research investigated the toxic effect of manganese, in a reduced chemical state, on rumen microbial metabolism and growth. The reduced form of manganese is the soluble state found in subsurface waters and has a high red-ox potential. In the study, we investigated the effects of reduced manganese at varying concentrations, on rumen microbial ability to replicate and metabolize carbohydrates. The hypotheses that we tested were as follows: (1) reduced manganese decreases the rate of pH drop associated with rumen culture fermentation of a com based diet and (2) reduced manganese decreases the bacterial growth in rumen culture, as measured by bacterial DNA quantification. In this study, rumen culture material was obtained from a rumen canulated cow and dosed with test materials in randomly assigned flasks at 37° C. Cultures were replicated three times on different days. Test materials were dosed to result in the reduced form of manganese at concentrations of 0 ppm, 1.5 ppm, 3 ppm, 6 ppm, 12 ppm, 24 ppm, 48 ppm, and 96 ppm. Samples from each flask were obtained at 0 hr., 3 hr., 6 hr., 9 hr., and 12 hr. for measuring pH and at 0 hr., 3 hr., and 6 hr. for DNA. In these experiments, manganese inhibited the growth of the microbial population at > 3 ppm, but the rate of pH drop was not altered among the treatments used in this study.

Recommended Citation

Dearing, Erin, "Investigation of the Toxic Affect of Manganese on Ruminal Microbial Digestion and Growth" (2005). Undergraduate Honors Capstone Projects. 805.
https://digitalcommons.usu.edu/honors/805