الفهرس 
Chapter I : IntroductionOnly 14 pages are availabe for public view
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Abstract
In this study we measured the width and the length of Moshtohor 2 E. tenella ( M2 E. tenella ) which was isolated from field outbreak in Kalyoubia province in 1999 by Saqr. It is a virulent strain and it is stored in refrigerator at 4 oC and passed under aseptic conditions every 3 months in one day old chicks. In 2000 we took this isolate and measured the length and the width of M2 E. tenella in our lab and we found that the average length of our reading was 22.40 µm versus 22.46 µm of Saqr while the average width of our reading was 18.36 µm versus 18.33 µm of Saqr which indicates that both readings were nearly similar.
DNA extraction:
DNAs were extracted from sporulated oocysts of M2 E. tenella strain (Saqr,1999), also from Coccivac B vaccine .
The results of PCR of M2 E. tenella and vaccinal strain, is that they were found at 278 bp. For more assurance that the two, (M2 E. tenella and vaccinal strain) are identical and sequenced in AB1 apparatus, we compared them with the results of Gen bank. We found that M2 E. tenella is shared from 96 to 98% in identity with cloned ones obtained from Gen bank and E. tenella vaccinal strain is showing high degree of identity from 94 to100%.
We used CLUSTAL W (1.82) multiple sequence alignment program to demonstrate alignment score as following:
Seq A Seq B Score
Houghton strain M2 E. tenella strain 97
Houghton strain E. tenella vaccinal strain 96
M2 E. tenella strain E. tenella vaccinal strain 96
We used Biological Sequence Alignment Editor Programme to verify points of mutations in M2 E. tenella strain and in E. tenella vaccinal strain from Houghton. We found some mutations in nitrogenous bases and in amino acids, so we carried out a challenge test to check if these changes can affect the efficacy of the vaccine. The challenge test proves the efficacy of the vaccinal strain as judged by the reduction in oocyst output, the increase in weight gain and the reduction of mortality rate .
The moleculobiological work in this study (DNA extraction, PCR, sequencing analysis and alignment in the Gen bank ) is a humble start for the construction of a recombinant vaccine against coccidial infection in Egypt.