The best time for colony characterization was 12~15 hours. Colonies are sticky, inoculated with needle hook can be drawn into wire, called "drawing" phenomenon. In the ordinary broth for 18~24 hours, the bottom of the pipe has flocculent precipitation, the growth of sterile membrane, liquid clear. The toxic strains were formed on the sodium bicarbonate plates and cultured in 20%CO2, and the mucoid colonies (capsules) were rough, while the avirulent ones were rough. (three) resistance, propagule resistance is not strong, easy to be killed by general disinfectant, and spore resistance, in a dry room temperature environment can survive for decades, in the fur can survive for several years. Once the pasture is contaminated, the spore can survive for years to decades. Boil 10 minutes or dry hot 140 hours 3 hours, can kill spore. Anthrax spore is particularly sensitive to iodine and is highly sensitive to penicillin, cephalosporin, streptomycin, kanamycin and so on.
Not viruses, anthrax bacillus, anthraci (Bacillus) belongs to aerobic bacillus, can cause sheep, cattle, horses and other animals and human anthrax. Anthrax was as lethal agents of imperialism. Herdsmen, farmers, furs and butchers are susceptible to infection at ordinary times. Skin anthrax is sporadic in our country, so we should not relax our vigilance. Biological characters (1) morphological staining: Bacillus anthracis is thick and ends are flat or sunken. Are like bamboo like, no power, no flagella, gram positive bacteria, the in sufficient oxygen, suitable temperature (25 to 30 DEG C) condition to form spores. No spores can be formed in living or dissected bodies. Spore oval, located in the middle of the bacteria, its width is less than the width of bacteria. Capsules can be formed in humans and animals, and in capsules incubated with CO2 and serum, they can also form capsules. The formation of capsules is a toxic feature. Bacillus anthracis is affected by a low concentration of penicillin, and bacteria can be enlarged to form a bead, called "beaded reaction"". This is also a unique reaction of Bacillus anthracis. (two) the culture characteristic of this bacterium is obligate aerobic, and it is easy to breed in common medium. The optimum temperature was 37 DEG C, and the optimum pH was 7.2 ~ 7.4. After 24 hours on agar plate, the rough colony of 2 ~ 4mm Diameter was developed. The colonies were ground glass like, irregular edge, like curly hair, there are one or several small tail processes, this is the expansion of reproduction in 5 caused by bacteria to 10% sheep blood agar plate, no obvious hemolysis ring around the colony, but a long culture can have mild hemolysis.
