AN EXPERIMENTAL-STUDY OF THE RATE AND DYN AMICS OF MOVEMENT OF VARIOUS FOODS OVER THE GREAT GERBIL DIGESTIVE-TRACT

The rate and dynamics of food movement over the digestive tract was st udied with the use of solid markers and small fragments of colored pla stic film, in five experimental groups of great gerbils kept on differ ent diets (various combinations of concentrated and cellulose food). T he concentrated food moves relatively uniformly over the digestive tra ct and is fully evacuated within 24-25 h. Addition of various plant ob jects rich in cellulose to the grain food and feeding of the gerbil on the cellulose food alone lengthened the period of food evacuation up to 50 h. This is due to food differentiation into rapidly and slowly m oving portions (the latter are delayed in the prostomach and caecum).