1921 Archives of Pediatrics & Adolescent Medicine  
New-born calves excrete feces during the first week of life which show distinct variations in the gross appearance. A study was made, therefore, of the amount of fat present in the feces, from birth to the time when the calves were approximately a week old. It is during this time that the calf readjusts its metabolic activities from that of an intra-uterine existence to one in which it subsists by absorption from its gastro-intestinal tract. It was found in general that the fat content of feces
more » ... at content of feces increases from birth to approximately the third day, after which it decreases and assumes an approximately normal level. At the time of the high fat content, there is present in the feces a greater proportion of fatty acids in the form of soap, indicating a lack of absorption on the part of the young animal. METHOD The method used for the determination of fat was a modification of the method developed by Saxon,1 which is in itself a development of the method of Meigs, for the determination of fat in feces. It seemed advisable to estimate the quantity of soap present in feces, as well as the total fat and fatty acids present as free fatty acids and soap. To do this we first extracted moist feces with ether and alcohol, according to the Saxon procedure, and then to the residue added hydrochloric acid to liberate the fatty acids from the soaps. The ether layer when removed contains a small amount of alcohol and acid; it was, therefore, collected in a separatory funnel and washed with distilled water until free from chlorids. This precaution is neces¬ sary to prevent the formation of ethyl esters of the fatty acids present. Comparative analyses showed this procedure to give, with suitable precautions, the same results as in the Saxon procedure. After we had commenced our analyses, the modification of the Röse-Gottlieb method by Holt, Courtney and Fales 2 appeared. These investigators applied a somewhat similar procedure to dried feces, by extracting with combined ether and petroleum ether. They derived their value for soaps by subtracting the results obtained by a nonacid
doi:10.1001/archpedi.1921.01910310062005 fatcat:m7d2snb6i5gqznpx5ax34w45hy