Effects of exogenous enzyme preparations on protozoan population and cellulolytic activity in the rumen of yearling rams

I. Varlyakov, P. Todorova, N. Grigorova, V. Radev, T. Slavov

Abstract: The effects of supplementing diets for yearling rams with exogenous enzyme preparations Hostazym C 100 and Hostazym X 100 on the total number of infusoria, their genetic composition and cellulolytic activity in the rumen were investigated. Nine ruminally fistulated yearling rams, divided into three groups of three animals each, were fed diets containing 1kg meadow hay and 1 kg barley-based concentrate, the concentrate of first group consisting of 1kg barley (ration I), the second – 0.8 kg barley and 0.2 kg sunflower meal and the third - 0,8kg barley (ration II) and 0,2kg sunflower expeller (ration III). The study was conducted in three periods - a control and two experimental ones. Hostazym C 100, respectively Hostazym X 100, was added to the rations during the experimental periods at a dose of 1g.kg-1 concentrated feed. Hostazym C 100 is a multienzyme product and has a predominant endo-1,4-β-glucanase and secondary cellulose, α-amylase, protease and hemicellulase activity. Hostazym X 100 has a predominant endo-1,4- β-xylanase activity and the same secondary activities. It has been found that: Hostazym C 100 and Hostazym X 100 did not affect the studied parameters in the ration with 93.2g.kg-1 crude protein and 18 g.kg-1 crude fats content (ration I). Hostazym X 100 increased the total number of infusoria, protozoa count from genus Dyplodinium and reduced the rate of Holotricha population in the diets with a 115g.kg-1 crude protein and 18,0g.kg-1 crude fats content (ration II) (p<0.05-0.001). The observed effects were lower by adding Hostazym X 100 in the same ration and at a higher level of crude fat in the diet (ration III) (p>0.05 – p<0.001). Hostazym C 100 reduced the degradation of cellulose in ration II (p<0.001). Hostazym X 100 increased the studied indicator in ration II (p<0.01) and in ration III (p<0.05).

Keywords: cellulolytic activity; exogenous enzymes; protozoa; rumen

Date published: 2019-06-14