The Length of the Intestine of Calves and its Bearing on the Absorption of the Nutrients from the Chyme

Abstract

In his recent book (1) Alvarez states, "Meat-eating animals have a simple stomach and colon and a short bowel, whereas grass-eating animals usually have a complicated stomach and colon, a large cecal pouch, and a long, small bowel. In carnivorous animals the small bowel is said to be only from four to eight times the body length, while in herbivorous animals it is from twenty-five to seventy-five times the body length." According to Swett and Graves (15) the length of the small intestine of mature beef cows (eight animals) varies from 93 to 140 feet and that of dairy cows (two animals) from 144 to 172 feet. From these data one finds that the post-mortem length of the small intestine of beef and dairy cattle is 28 and 33 times, respectively, the length from withers to pin bones, or within the lower limit suggested by Alvarez. The length of the large intestine of the same animals varies from 23 to 41 feet for beef animals and from 43 to 46 feet for dairy animals. Black, Semple and Lush (2) found that the average length of the small intestine of 20 seven-months old range steers was. 98 feet. One hundred and twenty days later the average length of the small intestine from a similarly bred group (32 animals) had increased to 110 feet. The average length of the large intestine for both groups was 21 feet. Such figures, of course, are only approximate in that the changing tone of the musculature of the intestine makes an exact figure impossible. Data concerning the length of the intestine of a live calf has only been reported on one animal (6). In this instance the length of the small in- testine of a six months old calf was found to be 21 feet two inches in the living animal and 68 feet nine inches on removal from the body. Since that time the following data shown in table 1 have been accumulated : From these data it is apparent that the length of the small intestine of the living calf is about seven times its body length, a figure somewhat out of line with that suggested by Alvarez. What influence this greater length of the small bowel has on digestion can be better understood by studying the movement of chmye in the gas- trointestinal tracts of carnivora and herbivora. Helle (I0) states that in dogs on a mixed meal, material began to appear at the lower end of the