Pathological effects of pine needle ingestion in pregnant mice.

Consumption of Ponderosa pine (Pinus ponderosa) needles causes reproductive dysfunction in mice during early and late gestation. Consumption during early gestation results in considerable embryotoxicity which is not a result of starvation. Temporary loss of coordination and lethargy are observed in the females. Consumption of the pine needle diet results in a weight loss which persists throughout gestation. Feeding the pine needle diet from the tenth day of gestation results in spleen atrophy observable by day twelve and adrenal hypertrophy by day thirteen. The adrenal hypertrophy is characterized by an increase in the medullary component of the gland from the normal 12% medulla present on day ten to approximately 35% medulla present in the glands of those females surviving past day fourteen. Few fetal deaths are observed prior to day fifteen but the incidence of fetal death reaches 80% by day sixteen of gestation. If the dead fetuses are not aborted, maternal death follows fetal death by approximately two days; however, if the dead fetuses are aborted the females survive.