The effectiveness of four commercial disinfectants including ammonium hydroxide, phenol, Eco.Bio (combination of QACs and gluteraldehyde) and Virox (combination of peracetic acid and hydrogen peroxide) was evaluated against unsporulated E. tenella oocysts which were obtained from naturally infected birds with ceccal coccidiosis then propagated in broiler chicks reared on wire cage and fed anticoccidial free starter ration from day one of rearing till the end of experiment. The oocysts were exposed to the disinfectants at different concentrations and different contact times. In addition, the effect of some environmental factors including temperature, pH and presence of organic matter on the efficiency of these disinfectants was also studied. Based on obtained results of the current study, it was observed that the most effective disinfectants against unsporulated E. tenella oocysts were ammonium hydroxide 5% and 10%, Phenol 10%, while Eco. Bio and Virox were less effective. Also, the results proved that the inhibitory activity greatly increased by increasing concentration or contact time or both for all tested disinfectants. While increasing the temperature factor, increased the efficacy of all tested disinfectants except Virox. In addition, for the factor of presence of organic, the results revealed that organic matter (10% chicken faeces) reduced the efficacy of both Virox and Eco.Bio disinfectants by 52.9% and 47%, respectively. While Ammonium hydroxide and Phenol disinfectants not affected by this factor. Finally, the highest efficacies of both Ammonium hydroxide and Eco.Bio disinfectants were obtained at alkaline pH, while for Phenol and Virox were active at acidic pH.
Key words: Disinfectants, E. tenella oocysts , coccidiosis.