Atmospheric ammonia (NH3) has been shown to be detrimental to poultry health and performance (Carlile, 1984; Kristensen and Wathes, 2000) and is cited as an environmentalconcernaswell(NRC,2003;USDA,2005). ExposuretohighconcentrationsofNH3(>50ppm)causes keratoconjunctivitis, with symptoms including watery eyes, closed eyelids, rubbing of eyes with the wings, and blindness(Bullisetal.,1950;FaddoulandRingrose,1950). Our recent study indicated that eye damage induced by the interaction of NH3 and light intensity decreased sig- nificantlybeginning1wkaftercessationofNH3 exposure (Olanrewaju et al., 2007a). In addition, from the same