Medium Without Rumen Fluid for Nonselective Enumeration and Isolation of Rumen Bacteria

Abstract

Beltsville, Md.), AND MARVIN P. BRYANT. Medium without rumen fluid for nonselective enumeration and isolation of rumen bacteria. Appl. Microbiol. 14:794-801. 1966.-Colony counts which approximated those in a habitat-simulating, rumen fluid-agar medium (RFM) were obtained in medium 10, a medium identical to the RFM except for the replacement of rumen fluid with 1.5 X 10-6 M hemin, 0.2% Trypticase, 0.05% yeast extract, and a 6.6 X 10-2 M volatile fatty acid mixture qualitatively and quantitatively similar to that in rumen fluid. Single deletion of Trypticase, yeast extract, or the volatile fatty acid mixture from medium 10 significantly reduced colony counts. Colony counts were also reduced when medium 10 was modified to contain higher concentrations of Trypticase or volatile fatty acids. Significant differences were found between colony counts obtained from diluted rumen contents of animals fed a cracked corn-urea diet, and the colony counts obtained from animals fed either a cracked corn-soyean oil meal or an alfalfa hay-grain diet. Qualitative differences were found between the predominant bacterial strains isolated from rumen contents of animals fed cracked corn diets and strains isolated from animals fed alfalfa haygrain. Regardless of differences in the predominant flora associated with diet, medium 10 and the RFM supported growth of similar bacterial populations. The results show that medium 10 is suitable for enumeration and isolation of many predominant rumen bacteria.

The Microbial Flora of the Rumen of Cows Fed Hay and High Cereal Rations and its Relationship to the Rumen Fermentation

“…Pounden & Hibbs (1948) concluded that with changes in ration there must be considerable adaptation of the 00ra to meet the changed nutritional conditions. Such variations have been reported (Gutierrez, Davis, Lindahl & Warwick, 1959;Bryant, Robinson & Lindahl, 1961;Caldwell & Bryant, 1966; Thorley, Sharpe & Bryant, 1968;Mann, 1970). However, only in a very few experiments have attempts been made to relate changes in rumen fermentation products to the microbial flora.…”

“…The procedure for the preparation of media, isolation and identification were essentially the same as those given by Caldwell & Bryant (1966) modified by Latham & Sharpe (1971). All incubations were a t 39".…”

The genetic diversity of lactic acid producing bacteria in the equine gastrointestinal tract

“…Two mature Standardbred castrate male horses with normal feet were dosed with 12.5 g kg À1 live weight oligofructose (Raftilose P95Ò) 1 by nasogastric intubation and developed laminitis prior to slaughter at 48 h. These two horses were part of a group of eight horses used in an experiment aimed at developing a horse, hind gut acidosis and laminitis induction model using oligofructose (OF). Blood samples were collected from the two horses dosed with OF and from two sham-infected horses at 0, 4,8,12,16,20,24,28,32,36,40,44, and 48 h after dosing for the analysis of D-lactate. Four mature Australian stock horses (2 castrate males and 2 females) were fed medium quality grass hay, two of which were deprived of feed and water for 6 h prior to slaughter while the other two had access to feed and water ad libitum.…”

Housing influences tissue cytokine levels and the fecal bacterial community structure in rats

“…Following the addition of 10 mL anaerobic 0.1% peptone water, the pellets were mixed to obtain homogenous slurries, and subjected to a 10-fold dilution series. Dilutions were plated on L-10 anaerobic medium to obtain the total anaerobic count (Caldwell & Bryant, 1966) and de Man-Rogosa-Sharpe medium (De Man, Rogosa, & Sharpe, 1960) for total lactobacilli. Plates were incubated in an atmosphere of H 2 /CO 2 /N 2 (10:20:70) at 38°C for 48 h, and the dilution plate having 30-300 colonies counted, with final counts expressed in terms of percentage of the total anaerobic count.…”