A medical retrieval device used to remove objects such as urinary and biliary calculi from the body comprising a handle assembly with an independent rotational means, a sheath, and an object entrapping assembly. The occlusion device includes an occlusion member and may also include a stabilizing member. The strains of Lactobacillus buchneri and Lactobacillus brevis disclosed in the invention have been purified and isolated and have been found to improve aerobic stability of silage allowing earlier aerobic exposure post ensiling than is presently practiced.