TABLE 3.
Body weight gain and lesion scores of chickens immunized with RASV strainsa
| Group | Primary immunization (wk 1) | Secondary immunization (wk 2) | Oocyst challengeb (wk 5) | Weight gain (g)c,d (wk 6) | Lesion scored,e (wk 6) |
|---|---|---|---|---|---|
| 1 | BSG | BSG | No | 157 A | 0 D |
| 2 | BSG | BSG | Yes | 129 C | 2.1 A |
| 3 | pYA3653 | pYA3653 | Yes | 130 C | 1.7 ABC |
| 4 | pYA3657 (EASZ240) | pYA3731 (EASZ240) | Yes | 135 BC | 1.4 C |
| 5 | pYA3658 (EAMZ250) | pYA3658 (EAMZ250) | Yes | 147 AB | 1.5 C |
| 6 | pYA3657 (EASZ240) pYA3658 (EAMZ250) | pYA3731 (EASZ240) pYA3658 (EAMZ250) | Yes | 142 BC | 2.0 AB |
a
Chickens were immunized with RASV strain χ8879 (ΔsptP1033::xylE ΔasdA16 ΔphoP233) harboring plasmid pYA3653, pYA3657, or pYA3658 or with RASV strain χ8916 (ΔphoP233 ΔasdA16) harboring plasmid pYA3731.
b
Chickens in groups 2 to 6 were inoculated with 105 E. acervulina oocysts.
c
Right before the oocyst challenge and on day 6 after challenge infection, body weights were recorded and weight gain was calculated.
d
Values followed by the same capital letter are not significantly different (P < 0.05).
e
Intestinal lesion scores were obtained using standard procedures.