Effects of mammalian blood with different glucose levels on reproduction, growth and survival of the southern medicinal leech, Hirudo verbana Carena, 1820.

Medicinal leeches are generally fed using pure mammalian blood. In the present study reproduction, growth and survival of medicinal leeches (Hirudo spp.) fed by mammalian blood with modified glucose level were investigated for the first time. Leeches were fed by cattle blood in a final glucose level of 152 mg/dL (control group; Glucose-free), 200 mg/dL (G200 group), 300 mg/dL (G300 group), 500 mg/dL (G500 group), 750 mg/dL (G750 group), 1000 mg/dL (G1000 group), 2500 mg/dL (G2500 group) and 5000 mg/dL (G5000 group) with the addition of D-Glucose Monohydrate. Greatest growth performance was determined in the G2500 group with a specific growth rate of 2.34% (final body weight: 10.37 ± 3.86 g) (P < 0.05). A quadratic increase was observed in the body weight values of the leeches depending on the glucose dose (P and P < 0.05). The greatest survival and gravidity rates were 89% and 38%, respectively, in the G750 group (P < 0.05). The increased glucose level caused a sharp decrease in the survival and gravidity rates of leeches. The glucose level did not significantly effected the cocoon and offspring productivity (P > 0.05). According to the broken line model, optimum glucose levels based on growth, survival rate and gravidity rate were 2461 mg/dL, 750.0 mg/dL and 749.9 mg/dL, respectively. The study showed that, although the optimum growth performance was obtained in the G2500 group, blood with glucose level of 750 mg/dL should be used for profitable medicinal leech culture considering survival and gravidity rates.