Circadian variation in the apparent digetibility of diets measured at the terminal ileum in pigs

Abstract

SummaryCircadian variation in the apparent digestibility of diets having different physical characteristics was measured in samples taken from the terminal ileum using simple cannulae and marker ratios. Six pigs were used in three latin squares involving three iso-nitrogenous diets (30 g N/kg D.M.). Diet A was based on barley, weatings, soyabean meal and fish meal, diet B included barley, weatings and oats and diet C was purified. The allocation of diet provided 100 g D.M./kg Weg0·75/24 h and in each latin square a different pattern of feed intake was used; diets were given at intervals of either 1 or 12 h, or ad libitum.Differences in the digestibility of the diets were consistently distinguished by the technique. The circadian variation in digestibility was related to the type of diet and could be modified by changing the number and distribution of feeds per day. The results show that an understanding of the variation associated with different diets and feeding methods is necessary for optimizing the strategy for sampling from the terminal ileum.