الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 210 |  |  |
| | | from | 210 | | |
Abstract
this thesis presents studies on isolation and production of
pure cultures of precocious and relaxed lines of ~. tenella. these
lines induced an immunity in day old male hy-line chicks. seven
hundreds and sixty one male hy-line chicks were used for this aim
(pm-p ose). the parameters used for differentiation between the
precocious, relaxed lines and m2-e.tenella parent strain were
measurement of width and length of sporulated occysts, body
weight and body gain, feed conversion ratio, oocyst production
and lesion scoring. the chicks used in this experiment were
inoculated with 250 sporulated oocysts of precocious, relaxed lines
and m2-e.tenella parent strain and challenged with 2 x io~
sporulated oocysts of m2-e.tenella parent strain at 28 days of age.
faecal material were collected daily from 4.5 days postchallenge
till the end of prepatent period of the parasite and the oocysts were
counted. the birds also were weighed weekly till 6 weeks of age to
determine the body weight and body gain. from this experiment,
the studies of reproduction and immunization of precocious and
relaxed lines detected. the oocyst output from immunized birds
with precocious and relaxed lines of e.tenella were lower than that
which were inoculated with m2-e.tenella parent strain.