Thrombus formation on indwelling venous cannulae in sheep : effects of time, size and materials.

Three experiments were performed to measure thrombus formation on plastic cannulae inserted by cut-down into veins of sheep. On polyethylene tubing, considerable thrombus was present after one day and the amount increased in the subsequent 13 days. When different sized polyethylene tubings were tested, thrombus tended to form in relation to the surface area.

Rates of passage of digesta and water absorption along the larg intestines of sheep, cows and pigs.

In 5 cows, the mean length of the large intestine was only slightly greater than that of 21 sheep and 3 pigs. At about one-fifth of the way along the large intestine of the sheep and cows, corresponding to the end of the proximal colon and start of the spiral colon, there were marked reductions in the amount of digesta present and in the lumen diameter. In pigs these parameters decreased gradually along the large intestine.