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چکیده
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The reproduction cycle of the cattle leech Limnatis paluda (Tennent, 1859) was studied under laboratory conditions, in two different tempratures (18±2 °C and 26±2 °C) and three different cocoon laying substrates (tile, moss, and stone). Reproductive parameters of the cocoons (i.e., number, size, weight, average hatching number, hatching rate) and hatchlings (i.e., Mean±SE numbers per cocoon and weight) were measured. To determine the effects of parameters on each other, correlation tests were conducted. No reproductive activity was occurred in the first thermal treatment (18±2 °C) for three months. After transferring all gravid adults to the second treatment (26±2 °C), the mean number and weight of the deposited cocoons were recorded as 4.00±0.35 and 0.1784±0.003 g, respectively. The mean length and width of the cocoons were 10.60±0.11 mm and 7.11±0.09 mm, respectively. The number of cocoons were not significantly different among deposition months (2 = 7.701, p = 0.173). Mean number and weight of offsprings per cocoon were recorded as 5.28±0.14 and 0.0188±0.01 g, respectively. No significant correlation was found between the length and width of cocoons with the number of offsprings. Correlation of the weight of cocoons with the mean number and weight of offsprings were significantly positive (r = 0.237, p = 0.005 and r = 0.340, p < 0.0005, separately). However, there was significant negative correlation between the number and weight of the hatchlings (r = - 0.395, p < 0.0005). Cocoon deposition was observed only on the wet moss medium and cocoon hatching occurred 26±2 days after deposition. The significant difference of cocoon weight in different months, increasing the number of cocoons per leech in 6th month of the study period, and fluctuation in the mortality and hatching rate of cocoons are assumed to be related to the feeding.
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