Effects of dietary protein on teratogenicity of ochratoxin A in rats

The teratogenic effects of a single subcutaneous dose of 1.75 mg/kg ochratoxin A given on day 6 of gestation was compared in weanling rats fed 5% protein diet for 4 weeks followed by normal protein diet (referred to as 5% normal protein diets) for the remainder of the experimental period, rats maintained on 10% protein diet, and rats on a normal protein diet throughout. These different diets are based on total dietary concentration of protein. Of the rats fed 10% protein diet, 22% failed to mate and in 39% failure of fertilization was observed. In rats fed 5% normal protein diets, the fertilization rate was 100%. Ochratoxin A treatment resulted in significant depression of fetal body weight in rats fed 5% normal protein diets and in rats maintained on normal protein diet throughout. Significant numbers of malformations (gross and skeletal) occurred in all the treated groups. Rats on a 5% normal protein diet and rats on the normal diet yielded a significant number of fetuses with internal soft tissue anomalies. The highest incidence of skeletal malformations occurred in ochratoxin A treated rats maintained on 10% protein diet throughout the experiment. Complete rehabilitation took place by replacement of low protein diet with normal protein diet.