The use of polymerase chain reaction for determination of virulence factors of Escherichia coli strains isolated from pigs in Poland

antigene antigens cell structure cerdo diarrea diarrhoea edema escherichia coli estructura celular fenotipos gene genes genotipos genotypes oedema pathogenicity patogenicidad pcr phenotypes polymerase chain reaction porcin structure cellulaire swine toxinas toxine toxins virulence