THE EFFECT OF AGE, BODY WEIGHT, FEED INTAKE AND ADAPTABILITY OF PIGS ON THE DIGESTIBILITY AND NUTRITIVE VALUE OF CELLULOSE

Abstract
A total of 88 metabolism trials were conducted with eight 65-kilogram pigs. Four pigs received a control ration and four received the same amount of control ration plus 40 per cent wood cellulose (solka-floc). A 4-week early growing, a 6-week maintenance and a 3-week late growing period were followed by a 2-week changeover period in which all pigs received solka-floc. The reduction of feed intake to a maintenance level caused an increase in the apparent digestibility of crude fiber and crude protein in both groups. This resulted in a higher digestible energy intake, carbon retention and body weight gain in the solka-floc group. The digestibility of crude fiber and crude protein of the solka-floc ration decreased in the late growing period but still remained higher than in the early growing period. The data indicated that digestibility was influenced more by the level of feeding and changes in body weight than by age. Pigs fed solka-floc for 15 weeks were no better adapted to digest it than those which received it for 1 week. Fecal protein was doubled by the addition of solka-floc. The solka-floc was 5.0, 29.1, and 18.3 per cent digested during the early-growing, maintenance and late-growing periods respectively, while the extra fecal protein resulting from feeding the supplemental cellulose was equivalent to 9.0, 6.7 and 8.1 per cent of the solka-floc intake. The relationship of dry matter content of the feces to digestibility and rate of passage is discussed.