Richard,
I have cultured almost 2 dozen stool samples over the past few years and with drug susceptibility test preformed have never found one that Albon or oxy-tet would work on.
They are about the weakest drugs you can use. Baytril and Gentamicin have almost always tested at the top of the list with gentamicin never letting me down.
Try the baytril with the fawn paste, I think you will like it. Good Luck
After dealing with ecoli many times I have developed a vaccine that has greatly reduced the prevalence of ecoli on my farm by close to a factor of 10. If you are interested in some info I would be glad to send it over. It also covers Fuso- bacterium ( lumpy jaw, foot rot and pneumonia.) this year is the largest group of people nation wide using it. I have seen tremendous results thus far.