Kankakee Valley Post, Volume 1, Number 11, DeMotte, Jasper County, 6 October 1932 — POULTRY [ARTICLE]

POULTRY

BREED FLOCK ABLE TO RESIST TYPHOID Possibility Demonstrated by Experiments. Six year’s selection and breeding of chickens that are resistant to fowl typhoid has reduced the percentage of dead chicks, inoculated with the disease germs, from 39.8 per cent in the first generation down to 9.4 per cent in the fifth generation, while the losses in nonresistant flocks used for comparison ranged from 93.2 per cent down to 85 per cent in the same number of years and generations, W. V. Lambert of Iowa State college reported to the international genetics conference at Cornell university. In the experiment, Doctor Lambert inoculated seven-day-old chicks with the fowl typhoid germ and selected breeding stock from the chicks whose families gave the highest resistance. Some inbreeding was done. Records of mortality, kept until the chicks were twenty-one days old, showed that most of the chicks which failed to survive from the selected strains died on the eighth day after inoculation, and most of the chicks from the unselected flock died on the fifth day after inoculation. Observations of 1,568 chicks of four different breeds, and from two strains of a single breed, showed these mortality percentages: White Leghorn, 87.7; White Plymouth Rock, 79.7; White Wyandotte, 93.4, and Rhode Island Red, 94.4. The differences, according to Doctor Lambert, probably represent strain resistance rather than breed resistance. Crosses between the selected and unselected stock show that the male as well as -the female transmits resistance to the disease. Back-crosses, he says, indicate that more than one factor is responsible for developing resistance and that continued investigation is necessary to establish the genetic behavior of these disease-re-sistant factors.