EIMERIA SPP OF THE DOMESTIC-FOWL - ANALYSIS OF GENETIC-VARIABILITY BETWEEN SPECIES AND STRAINS USING DNA POLYMORPHISMS AMPLIFIED BY ARBITRARY PRIMERS AND DENATURING GRADIENT-GEL ELECTROPHORESIS

The genetic relatedness of 5 Eimeria spp. of the domestic fowl, includ ing II strains of E. acervulina, 2 strains of E. tenella and 1 precoci ous line of E. acervulina, was assayed by means of random amplified po lymorphic DNA (RAPD) and denaturing gradient-gel electrophoresis (DGGE ). Seven different oligonucleotides were used to generate similarity c oefficients for the species and strains of Eimeria infecting chickens. Between 1 and 13 DNA segments, depending on the species/strain-primer combination, were amplified with the Various primers. Amplification p roducts ranged in size from 0.16 to 3.8 kb. E. acervulina strains demo nstrated two to four major common bands unique to the species. These s trains also exhibited major and minor differences in their DNA pattern s. Band-match analyses from both polyacrylamide and denaturing gradien t gels were used to calculate similarity coefficients for the Eimeria spp. and strains tested. Species differences, readily detected upon ex amination of DNA banding patterns, gave similarity coefficients of 4%- 38% and 3%-18% when analyzed by polyacrylamide- and denaturing gradien t-gel electrophoresis, respectively. A similar analysis of E. acervuli na strains yielded similarity coefficients of 55%-95% and 51%-85%, res pectively. The differences observed between both species and strains w ere greater when the RAPD-assay products were analyzed via DGGE, indic ating that a combination of these two techniques may provide a more st ringent analysis of the genetic relatedness of these coccidia.