Filicidal behavior: behavioral correlates and role of sensory systems

The administration of para-chloro-D,L-phenylalanine (PCPA) produces a high incidence of filicidal (pup-killing) behavior in female rodents. The present series of experiments determined the major behavioral, sensory, and temporal correlates of filicidal behavior in nulliparous adult Sprague-Dawley female rats. In Experiment 1, behavioral episodes involving the interaction of test pups and PCPA-induced filicidal females were videotaped, and subsequent analyses of behaviors related to locating, carrying, mauling, attacking, gnawing, and consuming the prey object were performed. Analysis indicated that the primary behavioral correlates in the PCPA animals included location, initiation of the attack (mauling), and killing of the pup (filicide). Only location was observed in control animals. Experiment 2 evaluated the effects of sensory impairments on location, mauling, and filicide. Sensory impairment occurred at 24 days of age for enucleation and 62 days of age for olfactory bulbectomies and/or auditory destruction. Animals were injected either at 110 or 130 days of age with PCPA for three consecutive days and tested for filicide for five additional days. Locating of the test pup was not affected by sensory impairment. Mauling was reduced significantly in the enucleation/auditory destructed animals. Filicide was significantly lower in animals with visual/auditory destruction, and, compared to controls, was reduced in all sensory impaired groups.