BACTERIUM PULLORUM INFECTION IN FOWL. 69 



Change of Reaction in Carbohydrate Media by the 112 Strains of Bacterium 



Pnllorum. 



Tlic cultures of Bact. pvUorum were gro\\Ti in test tubes of uniform 



length and caliber and in standard beef extract bouillon containing 1 per 



cent of the carbohj^drate. These results were somewhat lower than those 



obtained by Goldberg (8), who found bj^ using infusion broth that the 



percentage was higher. According to Hadley (10), on an average 0.7 per 



cent more acid is produced in sugar-infusion broth than in sugar-extract 



broth. Two drops of a bouillon suspension of each strain were used as the 



inoculum for a test, tripHcate titrations made, and the average percentage 



acidity noted at the end of the fifth daj'. It appeared from our work in 



relation to time of acid production that the maximum occurred between 



the fifth and tenth day. Therefore the tables and curves represent the 



amount of acid at the end of a five-day period, at 37.5° C, expressed in 



percentage normal acid. All titrations were made in the cold, using 



N N 



— NaOH and — HCl and phenolphthalein as the indicator. Gas produc- 



20 20 



tion was determined in dextrose, galactose, mannite, levulose, arabinose, 

 salicin, mannose, xylose, adonite, erythrol, saccharose, dulcite, dextrine, 

 lactose, raffinose, inuhn, maltose and glycerine. Durham double-barreled 

 fermentation tubes were employed, and the percentage of gas in the inner 

 tube read off on the Frost gasometer chart at the end of five days' incuba- 

 tion at 37.5° C. 



Dextrose. — This sugar was fermented by all the 112 strains. The lowest amount 

 of acidity was 0.6 per cent and the highest 1.8 per cent, the mean of 108 determina- 

 tions being 1.4 per cent acid. Gas was produced in this carbohydrate by all strains, 

 ranging in quantity from a bubble to 55 per cent, the average for all the 112 strains 

 being 20 per cent. 



Mannite. — The acid production in mannite was greater than in dextrose and 

 much more variable. After five days' growth the 112 strains had produced an 

 average of 1.0 per cent acidity. The exceptions to this average were strains 23, 

 46 and 72 which produced 2.0 per cent, 2.2 per cent, and 1.7 per cent, respectively. 

 Gas was produced by all strains, ranging in quantity from 20 to 50 per cent, with 

 an average for the 112 strains of 30 per cent. 



Galactose. — This sugar was fermented by all strains, being very much like 

 mannite and dextrose. The acidity ranged from 0.1 to 2.1 per cent, the average 

 for all cultures being 0.9 per cent. There were four exceptions which make a wide 

 variation in the curve, — strains 29, 33, 42 and 49, which produced 0.1, 1.9, 2.0 

 and 2.1 per cent, respectively. 



Levvlose. — This sugar was fermented easily by all strains of Bact. pullorum, 

 and the changes in reaction here correspond with those in dextrose, mannite and 

 galactose, the acidity ranging from 0.2 to 2.0 per cent, the average for the 112 

 strains being 0.9 per cent. The exceptions were strains 63, 72 and 73, which pro- 

 duced 2.0, 1.9 and 1.5 per cent acidity, respectively. 



Arabinose. — All strains fermented this carbohydrate, the acidity ranging from 

 0.5 to 1.0 per cent, with an average for the 112 strains of 0.7 per cent. This carbo- 

 hydrate was fermented in a very variable manner. 



Salicin. — None of the 112 strains fermented salicin. On the fifth day there was 

 marked alkaline reaction in some strains. The average acidity for the 112 strains 

 was 0.1 per cent. 



