[Biochemical characteristics of the causative agent of fowl typhoid]

Studied were the biochemical properties of a total of 563 Salmonella strains divided into two biotypes--S. gallinarum (542) and S. pullorum (21). The first ones were isolated from typhoid foci of chickens, poults, turkeys, pheasants, guinea fowls, pigeons, and starlings that had died of septicaemia. One strain was isolated from a 4-month-old pig. The S. pullorum strains originated from epizootiologically linked foci of pullorosis, being isolated from live chicken carriers, dead embryos, and down from hatcheries as well as from young chickens that had died in them up to the age of 20 days. The link is discussed between the biochemical properties of the isolated strains and their origin, and the importance of some biochemical tests employed to distinguished them. Attention is paid to the likeliness of isolating aberant strains of S. gallinarum with deviations from the morphology of colonies and their antigenic and biochemical characteristic typical of the species. Suggested is the employment of the tests for motility, dulcit, maltosa, ramnosa, sorbit, and ornithine for the rapid differentiation of Salmonella gallinarum from the closely related Salmonella species of D serologic group. In order to avoid the occurrence of confusion with other microbial species the tests for the demonstration of lactose, sodium malonate, phenylalanine, indole, hydrogen sulfide, and lysine-decarboxylase.