The Unique Finding of Rumen Protozoal Degradation of Grass Hay in Culture in the Presence of Anti-nutrient Gossypol

It has been known that rumen protozoa degrade plant cell walls and the removal of the rumen protozoa from rumen liquid decreased the degradation of cellulose and hemicellulose. However, the role of protozoa in the feed degradation in the complexity of the rumen microbial ecosystem remains challenging. The main aim of this experiment was to examine the effects of gossypol on rumen protozoa fermentation of grass hay (GH) with and without gossypol. The volumes of gas production were measured using the method of Menke and Steingass (1988). The results of this experiment show that gas production rate (c=0.081) from GH is higher than that of GH treated with gossypol 1mM (c=0.013), 5mM (0.013), 5mM (0.004). However, the potential gas production (a+b=17.1) and the asymptote (b=19.1) of GH were much lower than gossypol treated substrates suggesting that the presence of gossypol in the culture resulted in more gas from GH. However, the increase in gas production which occurred when gossypol was added to GH conversely correlated with the DM losses of the GH. In the presence of gossypol, there was a change in the molar proportions of VFA (Volatile Fatty Acids) suggesting that the presence of gossypol may have altered the fermentative activity of rumen protozoa in culture.