Taste differentiation in the context of suckling and independent, adultlike ingestive behavior.
The present study compared intake of sweet (saccharin), bitter (quinine), and neutral (water) tastants available either in the context of suckling behavior through a surrogate nipple or independent adultlike feeding through an intraoral cheek cannula in 3-hr-old newborn rats lacking any suckling experience and 24-hr-old rats with regular experience with the dam's nipple. The new technique of online monitoring of fluid flow was applied for assessment of the temporal patterns of ingestion. Newborn and 1-day-old rats tested in the context of suckling behavior showed extremely low intake of quinine, moderate intake of water, and high intake of saccharin. In the same way, they demonstrated low intake of quinine and high intake of saccharin in the context of independent feeding, but intake of water was also high and comparable to that of saccharin. Suckling rats attained higher efficacy of fluid extraction from nipple than pups drinking from cannula. The differential responsiveness to quinine, saccharin, and water in suckling rats was also manifested through attachment behavior, with pups spending less time on the nipple providing quinine and more time on the nipple with saccharin than on the nipple providing water. These results suggest that neonates show taste differentiation as early as 3 hr after birth, and that this taste differentiation is more pronounced in the context of suckling behavior than in the context of adultlike, independent ingestion.
Department of Psychology, Center for Developmental Psychobiology, Binghamton University-SUNY, Binghamton, New York, USA.
Andrey P
AP
Kozlov
Evgeniy S
ES
Petrov
Elena I
EI
Varlinskaya
Norman E
NE
Spear
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D004193:Discrimination Learning; D005247:Feeding Behavior; D005260:Female; D008297:Male; D009042:Motivation; D011247:Pregnancy; D051381:Rats; D012684:Sensory Thresholds; D013391:Sucking Behavior; D013649:Taste