Nonparturitional exposure to donor placenta and placentophagia after lateral hypothalamic lesions in rats

Previous research has shown that parturitionally experienced rats with lateral hypothalamic (LH) lesions that rendered them otherwise aphagic, still ate placenta when it was delivered (pregnant subjects) or presented (nonpregnant subjects). Subsequent studies have shown that some virgin rats are spontaneously attracted to donor placenta, whereas the others clearly avoid it. The present study was designed to demonstrate that the sparing of placentophagia after LH lesions observed in the earlier study was not due merely to the previous ingestion of placenta, per se, or to inadvertent selection for spontaneous placentophages. Virgin placento-phages were allowed to consume donor placenta; some were then bred. Prior to parturition or after an equivalent time interval, LH lesions were produced through indwelling electrodes. The next day, not only were the animals with properly placed lesions aphagic to a cookie/milk mash, but none ate delivered or presented placenta.