Infectivity to hosts of the endogenous stages of chicken and murine Cryptosporidium

Five groups of 4 mice each were inoculated with 10(6) Cryptosporidium muris oocysts. They were necropsied on days 2, 4, 6, 8 and 10. The stomach mucos a from each group were made into 10% suspension in physiological saline and were orally inoculated to 2 mice each. Recipients given suspension from in fected mice on day 6, 8 and 10 shed oocysts from 6, 9 acid 6, respectively. Similarly, White Leghorn received 106 Cryptosporidium sp. oocysts were kil led daily between 1 and 6 days. Recipients given bursa of Fabricius or caec um of donor birds on days 4, 5 and 6 shed oocysts. The endogenous stages of murine and chicken Cryptosporidium were able to infect the appropriate hos t.