Neurological development of kittens.

The neurological development of the kitten was studied from birth to 120 days of age. Three motor features present at birth disappeared within the 1st 45 days of life. The labyrinthine head and body righting reactions were present at birth; the latter matured only by 25 days of age when the air righting reaction (mature by 35 days) started to appear. Limb placing reactions developed progressively with proprioceptive components being present at birth whereas tactile components evolved slowly from early contact lifting to forepaws contact placing (60 days) and narrow plank walking (75 days). Standing and walking were well developed by 45 days. Eye opening occurred at 9.5 days and several eyeblink reactions (including blink to light) were present at birth. Adequate binocular coordination was seen by 47 days. Vision progressed parallel to the clearing of the ocular media which were fairly transparent by 32 days. Visually guided paw placing and the visuopalpebral blink reflex matured later (by 37 and 59 days, respectively). The external auditory canal and pinna were fully developed by 12 and 31 days, respectively; spontaneous and tactile pinna movements were present at birth; orienting to animal and nonanimal sounds was well developed by 6.5 and 18 days, respectively; spatial sound localization was developed by 16 days and differential responding to animal sounds matured by 24.5 days. Somatic responses and olfaction were present at birth but matured further thereafter. Playful interactions between kittens started by 10--15 days and well developed play behavior was seen by 36--40 days. In brief, all neurological functions mature progressively during the 1st 3 postnatal months.