Drug Resistance in Eimeria tenella. IV. The Experimental Development of a Nitrofurazone-Resistant Strain

Publisher Website
Google Scholar
Abstract
A strain of Eimeria tenella not previously exposed to drugs was propagated serially in chicks fed nitrofurazone-medicated marsh. For the first five passages, a suboptimal level of nitrofurazone (0.0028%) was used; for the following seven passages the concentration was increased to the manufacturer''s recommended level of 0.0055%. Although deaths occurred in all passages among birds fed suboptimal levels of the drug, in those fed the higher concentration there was no mortality until the fifth passage. As tolerance developed, the growth rate of the chicks progressively decreased and pathologic changes became more evident. Nitrofurazone-resistant oocytes from the seventh passage at the recommended level were resistant to zoalene, but not to arsenosobenzene, glycarbylamide, nicarbazin, Trithiadol, or Unistat.

This publication has 2 references indexed in Scilit: