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| | ===Example of a Protozoal Life Cycle=== | | ===Example of a Protozoal Life Cycle=== |
| | ''The following refers specifically to the life cycle of Coccidia spp.'' | | ''The following refers specifically to the life cycle of Coccidia spp.'' |
| | + | *The '''oocyst''' is the resistant stage in the environment |
| | + | |
| | + | *The infective '''sporozoite''' is released from the oocyst |
| | + | |
| | + | *Inside the host, the sporozoites invade the intestinal epithelial tissue |
| | + | **Sporozoites feed and grow |
| | + | |
| | + | *As the sporozoites grow the nucleus divides forming a '''schizont''' |
| | + | |
| | + | *The schizont contains numerous elongated '''merozoites''' |
| | + | |
| | + | *The formation of merozoites is the first asexual reproductive stage called '''schizogony''' |
| | + | |
| | + | *The schozont ruptures releasing the merozoites which also invade the epithelial cells |
| | + | |
| | + | *Another generation of schizonts form which is the beginning of the sexual phase of reproduction called '''gametogeny''' |
| | + | |
| | + | *The merozoites form male '''microgamonts''' or female '''macrogamonts''' |
| | + | **Collectively known as gamonts or gametocytes |
| | + | |
| | + | *The microgamonts released from the microgametocyte penetrate and fertilise the macrogamete (which is contained within the macrogametocyte) |
| | + | |
| | + | *Gametogeny forms the '''zygote''' |
| | + | **Surrounded by a cyst wall |
| | + | **Forms the '''oocyst''' |
| | + | |
| | + | *The oocyst is passed in the faeces as unsporulated |
| | + | |
| | + | *The oocyst becomes sporulated in the second asexula reproductive phase called '''sporogeny''' |
| | + | |
| | + | *Once the oocyst is sporulated it is infective |
| | | | |
| | ==Protozoa of Veterinary Importance== | | ==Protozoa of Veterinary Importance== |