Step 1: Understanding the Concept:
Maternal coccidiosis vaccination in poultry using affinity-purified gametocyte surface antigens (APGA) to confer passive yolk immunoglobulin protection to chicks.
Step 2: Detailed Explanation:
CoxAbic (Poultry Coccidiosis Subunit Vaccine):
- The world's first commercial subunit vaccine developed against avian coccidiosis.
- It contains affinity-purified gametocyte antigens (APGA) extracted from the sexual sexual stage (Gametocytes) of {Eimeria maxima (specifically Gam56 and Gam82 glycoproteins).
- Administered to broiler breeder hens; the maternal IgG (IgY) antibodies produced against wall-forming gametocyte antigens are transferred via egg yolk to newly hatched progeny chicks, blocking oocyst wall formation and conferring broad passive cross-protection against E. tenella, E. maxima, and E. acervulina.
Step 3: Final Answer:
Thus, CoxAbic contains Gametocytes of Eimeria maxima, corresponding to option (D).