Rumen Bacteria in Cobalt-Deficient Sheep

Abstract

After 8 months on a Co-deficient diet 21 yearling sheep were divided into 3 equal groups; the 1st fed 1 mg./ day of Co, the 2d injd. with an equal amt, and the 3d kept on Co-deficient diet. Co deficiency symptoms were relieved in Co-fed group, but not in others. Comparison of rumen samples after 1 and 2 weeks on the above regime showed large numbers of Gram-positive slender curved rods and coccoid bacteria and largely decomposed cellulose fibers in Co-fed animals, while Co-deficient and injd. animal samples showed complete lack of slender curved rods and greatly reduced numbers of coccoid forms on fibers which were only slightly decomposed.