The characteristics of some rumen lactobacilli.

During the past few years several investigators have reported the isolation of lactobacilli or lactobacilli-like organisms from the rumen liquor of cattle and sheep. Gall and Huhtanen (1951) isolated several gram positive, nonsporeforming rods from rumen fluid which produced lactic acid from glucose, but they were not further identified. Some lactobacilli found by Rodwell (1953) in a sheep's rumen were described as resembling Lactobacillus leichmannii or Lactobacillus delbrueckii. Huhtanen and Gall (1953) isolated two types of rods from rumen fluid which they stated were closely related to the genus Lactobacillus. Wasserman et al. (1953) characterized some isolates from a bovine rumen as variants of Lactobacillus bifidus. A rumen lactobacillus was classified into a group containing Lactobacillus brevis, Lactobacillus buchneri, and other heterofermenters by Briggs (1953b). L. brevis, an anaerobic variety of Lactobacillus lactis and an organism similar to the motile lactobacillus of Harrison and Hansen (1950) were discovered by Mann and Oxford (1954) in the rumens of young calves. Mann and Oxford (1955) also found Lactobacillus fermenti and Lactobacillus acidophilus in the rumens and abomasums of calves and kids. The number of lactobacilli in the rumen appears to vary with the diet, according to Briggs (1955), who reported that lactobacilli predominated in the rumen of animals on concentrate diets, but were less numerous in grass-fed animals. This report deals with the isolation and identification of lactobacilli mainly from bovine rumen fluid. A sample of ovine rumen fluid yielded two cultures in some preliminary work which stimulated the investigation leading to this report.