Interference of mycotoxins with prenatal development of the mouse. II. Ochratoxin A induced teratogenic effects in relation to the dose and stage of gestation.

Ochratoxin A was dissolved in corn oil and administered by stomach tube to pregnant CBA mice in varying dosages. On gestation day 8 or 9 the dams were treated with a dose of either 1, 2 or 4 mg/kg body weight and on 1 of various other days (2, 4, 6–7, 10–14, 16) or 2 days prior to conception they were supplied with a dose of 4 mg/kg. The highest amount of the toxin given on day 7, 8 or 9 decreased the prenatal survival and on day 9 diminished the foetal growth. A marked impairment in foetal growth also resulted from treatment before conception. Overt craniofacial anomalies were produced only by exposure on day 8 or 9 and their incidence, multiplicity and severity increased with increasing dosage, the peak effect being on day 9. A study of the anatomical features of the craniofacial skeleton disclosed the failure of closure of neurocranium and an abnormal configuration, position and size of the bones of the base and lateral walls of the skull.