Olfactory bulbectomy and play fighting in juvenile rats

To determine the influence on play fighting of inputs to the brain that arise in or course through the olfactory bulbs juvenile male and female rats were bilaterally bulbectomized at 23 or 24 days of age. The frequency of play fighting and play initiation was observed in tests conducted in the home cage. Bulbectomy did not affect the frequency of play fighting or play initiation by males, but slightly increased the frequency of play fighting without altering play initiation in females. Since peripheral anosmia has only modest effects on play fighting, neither the chemosensory nor the modulatory influences of the olfactory bulbs on limbic system activity appear to be especially important in the control of play by juvenile rats.