| Abstrakt: |
A 44-acre field of alfalfa hay was laid off in 16 one-acre plots with intervening buffer strips. The 16 plots were divided into 4 blocks of 4 plots each. DDT was applied to the plots at the following levels per acre: (1) none; (2) 1 pound; (3) 2 pounds; (4) 4 pounds. In addition another lot of alfalfa hay was procured to feed to lambs along with DDT in capsules at the following amounts in parts per million of hay: 0, 50, 100, and 200. Thirty-two Rambouillet and 32 Rambouillet × Columbia lambs were segregated according to breed and weight and allotted to the eight treatments at random. They were fed individually for 112 days. Digestion coefficients, total digestible nutrients, nitrogen balance and metabolizable energy were determined on 4 of the field treated plots of alfalfa hay using 4 lambs in a Latin square design. The collection period lasted 7 days.The average DDT residue on the alfalfa hay was 0.0, 15, 22, and 42 parts per million when 0, 1, 2, and 4 pounds of DDT was applied per acre of alfalfa.The DDT dusted alfalfa hay had a greater ether extract content, carotene content, and yield of dry matter per acre.There were no apparent differences among the alfalfa hays in content of protein, ash, crude fiber, nitrogen free extract, phosphorus, or calcium.There were no apparent differences among the alfalfa hays in the digestibility of protein, ether extract, crude fiber, and nitrogen free extract or in the amount of total digestible nutrients.The DDT dusted alfalfa hays had an increased metabolizable energy content when compared to the non-dusted alfalfa hay.There was an increase in nitrogen balance as the amount of DDT residue decreased on the alfalfa hay.There were no apparent differences among the DDT-treated field hays or the laboratory hays in rate of gain, total gain, and feed consumption of the lambs.The average amount of DDT present in the mesenteric and kidney fat was 1.9, 15.8, 18.2 and 44.2 ppm in the lambs consuming alfalfa hay dusted with 0, 1, 2, and 4 pounds of active DDT per acre, respectively. The average amount present in the mesenteric and kidney fat of lambs receiving DDT in capsules was 0, 19.6, 32.1, and 73.4 ppm when 0, 50, 100 and 200 ppm DDT, respectively, were fed.The average amount of DDT in muscle, liver, kidney, and brain varied from 0 to 1.7 ppm. |
