Page:Bergey's manual of determinative bacteriology.djvu/214

 Produces a characteristic black-rot in hen eggs. Pathogenic for frogs, salamanders, fish, mice, guinea pigs and rabbits, causing hemorrhagic septicemia. Causes a hemor- rhagic septicemia in snakes. In this case the disease is transmitted by mites (Camin, Jour, of Parasitol., 34, 1948, 345). Source: Isolated from frogs dead of septicemia (red leg). Habitat: Water and infected fresh-water animals.

4. Aeromonas salmonicida (Lehmann and Neumann, 1896) Griffin, 1954. (Bacillus der Forellenseuche, Emmerich and Weibel, Arch. f. Hyg.jBl, 1894, 1; Bacterium salmoni- cida Lehmann and Neumann, Bakt. Diag., 1 Aufl., 2, 1896, 240; see Mackie, Arkwright, Pryce-Tannatt, Mottram, Johnston and Menzies, Final Rept. of the Furunculosis Committee, H. M. Stationery Office, Edin- burgh, 1935; Griffin, Trans. Amer. Fish. Soc, 83, (1953) 1954, 241.) sal.mo.ni'ci.da. L. noun salmo, salmonis salmon; L. v. suffix -cida from L. v. caedo to cut, kill; M.L. fem.n. salmonicida salmon- killer. Description taken from Griffin (Trans. Amer. Fish. Soc, 82 (1952) 1953, 129). Rods, 1.0 by 1.7 to 2.0 microns, with rounded ends, occurring singly, in pairs or in chains. Non-motile. Gram-negative. Gelatin stab: Crateriform to infundibuli- form liquefaction in 1 to 3 days; complete liquefaction in 7 days. Growth filiform, beaded, best at top. Medium turns light brown near the surface of old cultures. Agar colonies : Circular, punctiform in 24 hours and 1 to 2 mm in diameter in 4 to 5 days, convex, entire, semi-translucent. Colonies and medium turn brown in old cultures. Agar slant: Growth abundant, butyrous, glistening, filiform, opaque to transparent, odorless, colorless. A soluble, brown, me- lanin-like pigment forms in 3 to 5 days. A bright salmon-pink color develops when i8-2-thienylalanine is present (Griffin, Snieszko and Friddle, Jour. Bact., 65, 1953, 658). Colonies developed on trypticase agar quickly turn a violet-black color after the addition of 1 per cent aqueous p-phenyl- enediamine (Griffin, Proc. 52nd Gen. Meet- ing, Soc. Ajner. Bact., Boston, 1952, 53; also see Vet. Med., 48, 1953, 280). Broth: Moderate to strong clouding; no ring or pellicle; moderate, flocculent sedi- ment. Medium may clear in the upper layers and some growth may adhere to walls of test tubes of old cultures. Litmus milk: Slight and temporary acidi- fication. Complete peptonization in one week. Rabbit blood agar: Beta-hemolysis in 2 days. Indole not produced. Nitrites produced from nitrates. Ammonia produced in tryptic digest of casein-yeast extract medium. Hydrogen sulfide not produced. Methyl red negative; acetylmethylcarbi- nol not produced; sodium citrate does not serve as a sole source of carbon. Urea not attacked. Acid and gas from glucose, fructose, maltose, galactose, arabinose, mannose, starch, dextrin, glycogen, salicin, esculin and mannitol. Lactose, sucrose, xylose, rhamnose, trehalose, melibiose, cellobiose, raffinose, melizitose, inulin, amygdalin, methyl glucoside, glycerol, erythritol, adonitol, sorbitol and dulcitol not attacked. Starch hydrolyzed. Arginine and methionine are essential for growth; asparagine and leucine are highly stimulative while lysine is only moderately so (unpublished data, Griffin). Temperature relations: Optimum, be- tween 20° and 25° C. Minimum, 6° C. Maxi- mum, 34.5° C. Aerobic, facultative. Pathogenic for most fresh-water fish, particularly those belonging to Salmonidae. Source: From dead fish, of the family Salmonidae, taken from a fish hatchery in Southern Germany. Habitat: Found in fresh-water lakes, streams, rivers and fish ponds throughout Europe and also in the United States and Canada. Causes a furunculosis in infected fish; also occurs in apparently normal fish.