Feeding and drinking patterns in young pigs.

Feeding and drinking patterns of six immature female pigs, weighing from 10 to 130 kg, operantly obtaining feed and water at a fixed ratio of 10, were determined. It was found by log survivorship analysis that 10 min was the minimum interbout interval defining separate eating bouts. As the pigs grew through this weight range, daily feed intake increased nearly threefold, while eating bout frequency fell from 14 to 7 per day; consequently both eating bout size and interbout interval increased. However, bout size was increased primarily by an increased rate of eating during bouts without any consistent increase in bout duration. Neither premeal nor postmeal intervals were correlated with meal size. Of the pigs' daily water intake, 75% was closely associated with eating bouts and over 1/3 of this (25%) was preprandial. Sixty-four percent of daily food intake and 68% of water intake was during the 12-hr light period. Nocturnal eating bouts were less frequent, but larger.