Resumen:
Enteric methane production from ruminants contributes to current global warming challenges faced by
mankind. Supplements that improve nutritive value of diets are potential mitigating strategies that may
reduce enteric methane emissions. This study was, therefore, designed to evaluate the potential of
duckweed (Lemna gibba) supplement to reduce enteric methane emissions using an in vitro ruminal gas
production technique. In the first of two experiments, Lemna gibba from two water bodies (LG1 and LG2),
lucerne and ryegrass samples were analyzed for chemical composition and in vitro ruminal fermentation
parameters. In the second experiment, the two Lemna gibba samples were each included in a basal diet at
5, 10, 15, 20 and 25% to create ten dietary treatments. The dietary treatments were also analyzed for
chemical composition and in vitro ruminal fermentation characteristics as in the first experiment. Lemna
gibba and lucerne fermentation resulted in similar propionate levels. The inclusion of 15% L. gibba had no
effect on the ruminal fermentation patterns (volatile fatty acids, acetate:propionate ratio, acetate, propionate
and butyrate) and the dry matter and organic matter degradability. These results indicate that
L. gibba could be used in ruminant diets as an alternative to grains or concentrates with the added
advantage of possibly reducing ruminal methane emissions. Dietary supplementation with L. gibba in
ruminant diets could be an environmentally friendly strategy to reduce feed costs and ensure sustainable
production