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This is the second in a series of reports on the growth, feed intake and digestibility responses of growing swine (50 to 110 pounds) involved in a 2 × 2 × 2 × 2 factorial test of the effects of wheat bran, pelleting, antibiotics and type of protein in the ration. Discussion in this paper was restricted to those factors affecting the responses to the inclusion of wheat bran.With approximately isocaloric diets the inclusion of 10 per cent bran resulted in a general increase of 6 per cent in feed intake (P =

Two experiments were carried out with Hereford and Aberdeen Angus steer calves to study the influence of feeding concentrate and hay in the ratios of 1:2, 1:1, 2:1; of feeding the concentrate in the pelleted and the ground form; of pelleting the entire ration; and of feeding the ration ad libitum and according to the body weight of the animal. All comparisons were not made in each experiment. Each lot in each experiment was made up of four Aberdeen Angus and seven Hereford calves. All animals were fed individually. Only the data obtained between 500 and 900 lb. body weight were considered in this paper. The animals were slaughtered as they reached 900 lb. and certain carcass data obtained.The steers fed concentrate to hay in the ratio of 1:2 made smaller daily gains, required more feed (T.D.N.) per unit of gain, had lower dressing percentages, and had less fat in their 9-10-11 rib sections than those fed rations with ratios of concentrate to hay of 1:1 and 2:1. The steers fed the 1:1 ratio made significantly smaller daily gains and required more feed per unit of gain than those fed the 2:1 ratio of concentrate to hay, but were not different in dressing percentage or percentage fat in the 9-10-11 rib sections.There were no significant differences between those steers fed their concentrate in the pelleted or ground forms. In one experiment, pelleting the entire ration resulted in significantly lower daily gains than pelleting only the concentrate and feeding the hay chopped, but in the other experiment there were no differences. Pelleting the entire ration resulted in no significant differences in feed efficiency, dressing percentage, or carcass grade. Limiting the daily consumption of feed to predetermined amounts dependent upon body weight did not influence efficiency of feed utilization or carcass characteristics as compared to ad libitum feeding.The Hereford steers that were fed in these two experiments made greater body gains per unit of feed consumed but had less body fat and in one experiment had lower grading carcasses than the Aberdeen Angus steers.

A swine feeding trial, of 2 × 2 × 2 × 2 factorial design, involving 64 pigs (32 gilts and 32 barrows) weighing initially 50 ± 2 pounds and fed to a final weight of 110 ± 2 pounds was carried out. The dietary variables were meal vs. pellets, 0 vs. 10 per cent wheat bran, mixed animal-plant vs. all-plant origin protein supplement and 0 vs. 33 p.p.m. of an antibiotic mixture (penicillin, streptomycin and chlortetracycline). Weight gains and feed intakes were recorded bi-weekly and a Cr2O3-marker digestion trial was imposed on 32 pigs during the feeding test.The results revealed distinct interrelationships among all four experimental variables that prevailed through to the highest order statistical interaction. Consequently discussion in this paper was restricted to those factors affecting the responses to pelleting.On the whole there was no advantage due to pelleting. However, in the absence of bran and antibiotics, and particularly when no animal protein was involved, pigs fed pelleted feed gained faster and had better feed efficiency. Pelleting was found to increase dry matter and energy digestibility when no bran or antibiotics were included in the diet. Conversely, the inclusion of either bran or antibiotics was as effective as pelleting. It is postulated that bran and antibiotics were effective by reason of their effects on the physical nature of the ingesta and on the microbial population of the gastrointestinal tract.