Relationship of Particle Size to Coccidiostatic Efficacy of Buquinolate

Two trials comparing buquinolate of 2 average particle sizes (1.6 and 6.1 μ) indicate the smaller particle size to be more effective in controlling the incidence and severity of bloody droppings, cecal lesions and numbers of oocysts passed by chickens with Eimeria tenella coccidiosis. This difference is particularly striking at levels below the use level of 0.00825% recommended for buquinolate. No chicks died that received either milled or micronized buquinolate at levels of 0.0055% and above. Micronized buquinolate protected against death better than did milled buquinolate at the 0.00275% level. Further comparisons of buquinolate of 2 average particle sizes (1.8 and 6.1 μ) against mixed infections of Eimeria acervulina and E. tenella, each from 2 different strains, under battery conditions indicated that micronized buquinolate (1.8 μ) had superior anticoccidial activity over milled buquinolate (6.1 μ) against both species.