Acute oral ochratoxicosis in day-old White Leghorns, turkeys and Japanese Quail.

The comparative acute, oral toxicity of ochratoxin A for three day-old avian species is presented. The seven-day LD50 value for White Leghorns was calculated to be 3.4 +/-0.19 mgm./kg., for turkeys to be 5.9 +/- 0.72 mgm./kg., and for Japanese quail to be 16.5 +/- 0.56 mgm./kg., body weight. The dose-response curves are linear and parallel through one standard deviation on either side of the LD50 when log-dose is plotted against probit for survivors. It is suggested that the mechanism of action of ochratoxin A is similar in the three species, though the potency differs. The reduction in weight gain of Leghorn survivors was proportional to dose, and was observed in two separate traials over an overall dosage range from 0.2 mgm./kg. to 5 mgm./kg. The turkeys showed only a slight reduction in weight gain at doses less than 4mgm./kg., a more marked reduction being observed at higher dose levels. The quail did not show reduction of weight gain at dose levels below 10.9 mgm./kg., though the reduction was proportional to dose at higher levels. All birds dying of acute ochratoxicosis revealed a progression of symptoms from listlessness, huddling, occassionally diarrhoea, ataxia, prostration and death. Viscereal gout was observed at necropsy of the Leghorns.