[Experimental vaccination of SPF chickens against Newcastle disease using the method of coated-millet vaccine from a thermotolerant variant of the LaSota virus].

The thermotolerant variant A300 of LaSota virus was used to vaccinate 4 week old specified pathogen-free (SPF) chickens by feeding them with virus coated-millet. With vaccine doses above 10(6)EID50/bird, HI antibodies developed and protection to challenge was seen 2 months after vaccination, while 100% mortality occurred in the control groups. The PD50 was estimated to 10(6.85) EID50. This lyophilized vaccine intended for African village chickens can be kept at ambient temperature for at last 1 week up to 35 degrees C. Other trials on a large scale are still needed to determine the potential of this vaccine in the field conditions of rural Africa.