Effects of casein blood substitute feed on growth, survival and reproduction of native Iranian medical leech, Hirudo orientalis

Abstract

This study aimed to investigate the effects of casein blood substitute feed on the growth, survival and reproduction of Hirudo orientalis. At first, 100 leeches with an average weight of 3 g were reproduced. The growth indices of 200 leeches (with an initial weight of 0.038 ± 0.012 g) were measured during 10 months and also reproductive characteristics of 50 leeches during the 8th to 10th months. Leeches were fed at 30-day intervals under two treatments: using fresh blood (T1) or blood substitute feed (T2). During the rearing period, the growth of blood-fed leeches (T1) was significantly (p<0.05) faster than the blood substitutes-fed group (T2). In the 10th month, the two groups exhibited an 18% weight difference with each other. Although the amount of weight, length, diameter and number of cocoons produced in T1 were higher than T2, however the differences were not statistically significant (p<0.05). Survival rate was higher in T1 during growth and reproduction. Fertility was diagnosed in almost all adults in T1 (98%) and in most leeches of T2 (91%). The number of infants in T1 was significantly (p<0.05) higher than T2. It can be concluded that casein blood substitute feed causes less growth, reproduction and survival rate compared to fresh blood (p<0.05) in H. orientalis. However, due to health and breeding problems, using fresh blood in the reproduction and breeding time intervals of the leeches on the one hand, and the proximity of the results of the two treatments on the other hand, it can be concluded that the blood substitute feed reduces production costs, facilitates feeding of leeches and producing hygienic leeches, hence.

Keywords

• medicinal leech
• nutrition
• casein
• growth factors
• hirudo orientalis