Selective Induced Altered Coccidians to Immunize and Prevent Enteritis

Table 3

White Leghorns were immunized with 240 and 2400 normal (N) or altered (A) oocysts of E. tenella with a two-week interval. Infected control group (N) received no previous immunization before final challenge. Remaining birds were challenged each with 24,000 normal oocysts. Controls (C) received (0) sham inoculation. N lost weight the most and developed moderately severe lesions. Body weight gain/g was significantly higher in uninfected animals and those immunized with altered compared with the normal organisms and there was weight loss in unimmunized animals. animals/group. , . ND = not done.

Group	Strain	Oocyst/	Weight gain	Lesion	Ab titer (OD)
7	A	24,000	71 ± 4	0	50.0
8	N	24,000	21 ± 4	0	38.0
9	N	24,000	−50	3.5 ± 0.5	ND
10	C	0	171 ± 4	0	0