Fig. 6.

Changes in body mass for up to 60 days following feeding on blood or on an arginine–saline solution. (A) Mass gains, and subsequent losses, of the seven blood-fed leeches, expressed as the average percentage of mass for each leech relative to its pre-feeding mass for the 60 days after feeding to satiation. Leeches were fed on day 0. (B) Mass gains, and subsequent losses, of the 11 arginine-fed leeches, expressed as the average percentage of mass for each leech relative to its pre-feeding mass for the 8 days after feeding to satiation. Error bars represent s.e.m. The letters above the data points represent classes of points that are statistically different from one another according to t-tests (P<0.01).