Adsa Logo White Adsa Title White

In vitro dry matter digestibility of Typha domingensis using adapted rumen microbes.

S. LeShure Ratiff



Join S. LeShure Ratiff on this page for a live text chat!
6:00 PM - 8:00 PM GMT


In vitro dry matter digestibility of Typha domingensis using adapted rumen microbes.
S. LeShure Ratiff*, R. Kohn. University of Maryland College Park College Park, MD.

There is a shortage of usable firewood for cooking in rural Nigeria. Bio-digesters serve as an eco-friendly, inexpensive cooking fuel by converting common waste into valuable biofuel/biogas, such as methane. Typha domingensis, also known as cattails, has become a nuisance aquatic weed that overpopulates and pollutes Nigerian waterways. Utilizing cattails as substrate for digesters would help rid Nigerian waterways of this weed and relieve the firewood shortage. The source of inocula used to “seed” bio-digesters is also being considered, whether to use rumen fluid from cattle gut harvested at slaughter or microorganisms from already established digesters. Rumen fluid often yields a faster digestion rate than biogas digesters, possibly because of selection caused by faster passage rates in the rumen. We conducted an experiment to evaluate cattail digestion in vitro. The hypotheses were (1) wild-type rumen microorganisms may bring about faster digestion rates over time when compared with substrate-adapted digester microorganisms, and (2) faster organic matter flow rate would increase digestion rate of digesters. We compared the digestion rate and methane production for rumen fluid versus inocula from 2 bench-scale digesters. These digesters were previously conditioned to pre-bloom cattail and fed at 2 organic feeding rates (FR = 0.04 g/d or 0.08 g/d). Each of the 3 sources of inoculate used with 5 differing maturities of Typha domingensis. Forage digestion rate and extent of digestion were greatest for rumen fluid, but the slower FR digester yielded similar digestion rates as the rumen fluid for pre-bloom cattails. The slower FR produced the most methane as a percentage of organic matter, and had higher digestion rate than the faster FR digester. The faster FR did not explain why rumen fluid yielded faster organic matter digestion rates.

Keywords: Typha domingensis, cattails, anaerobic digesters.