| Abstrakt: |
Seventy-two Minnesota #1 × Duroc weanling pigs were alloted to 8 groups according to weight, breeding and sex. These animals were fed 4 levels of alfalfa meal (0, 10, 30, and 50 percent of the ration) with and without aureomycin (10 mg. per lb. of feed) in balanced, pelleted rations. All pigs were slaughtered as soon as possible after they reached 200 lb. body weight. Carcass data and organ weights were obtained. As the level of alfalfa in the ration increased, the rate of gain, dressing percentage, depth of back fat, and the percent of bacon belly and fat back in the carcass decreased significantly while the percent of shoulder, ham and loin in the carcass and the weight of the stomach and large intestine increased significantly. The pigs fed aureomycin gained significantly faster with less feed per pound of gain than the controls. None of the treatments had any effect upon the carcass length, number of ascarids, or weight of the spleen, liver, small intestine, lungs or heart. These data indicate that hogs may use up to 50 percent alfalfa in their rations and produce leaner carcasses than control pigs fed a conventional ration. Aureomycin accelerated the growth rate and decreased the feed required per pound of gain even at high levels of alfalfa feedings. Swine apparently adjust to a high level of alfalfa intake by enlarging the size of their digestive tracts where limited transitory feed storage takes place as indicated by the increased weights of the stomach and large intestine. |
