Experimental Influenza in Sheep. ∗

Abstract

Summary and conclusions

Of 9 lambs given viable Type A influenza virus via the intratracheal route, only the first 2 inoculated suffered clinical illness. Their illness was not respiratory in nature. Infectious virus was not recovered from 4 animals using nasal swab materials or lung and tracheal tissues. All lambs responded immunologically to primary intratracheal inoculation of virus, and second inoculations resulted in significant rises in homologous HI antibody titer. Further inoculations of virus served to broaden the antibody response without increasing the peak homologous antibody titer. The antibody titers reached suggest the feasibility of using lambs for large-volume production of anti-influenza typing sera.