Differential effects of upper gastrointestinal fill on milk ingestion and nipple attachment in the suckling XXXX .

@entity35 @entity1347 @entity7298 @entity146
Milk intake and nipple @entity146 were studied in the natural suckling situation after gastrointestinal preloading. @entity35 pups, deprived of their dam for 9 hr at 1, 10, or 20 days of age, were preloaded by gavage with volumes ranging from 2 to 16% of their body weight and returned to suckle. Preloads of artificial bitch's milk decreased the intake of mother's milk in a volume-related manner at all ages. At 1 and 10 days 4% preloads decreased milk intake without affecting @entity146 ; larger preloads of 8 and 16% decreased intake and reduced the incidence of attachment. At 20 days of age small and large preloads decreased both incidence of attachment and milk intake. Preloads up to 8% of body weight had no effect on latency to attach at any age. Complete subdiaphragmatic bilateral vagotomy increased milk intake of 7-9 day-old pups fed automatically through an @entity1347 in a nonsuckling situation. Vagotomy combined with spinal cordotomy (T2-T3) resulted in a synergistic @entity7298 and massive distension of the upper GI tract. The results indicate that suckling @entity35 can control their intake of mother's milk while remaining attached to a nipple as early as 1 day of age. The suppression of ingestion in response to GI filling appears to be mediated by visceral afferent activity. Conversely, @entity146 are less affected by GI fill. This suggests that @entity146 and @entity146 have different controls during the 1st 10 days of postnatal development.
