First report of infection with Ligula intestinalis in Aphanius persicus in Barme-e-Shoor Spring- Stream System, Maharlu basin, Shiraz, Iran

Objective: Aphanius persicus is an endemic species found in streams and springs drain to Maharlu Lake, Shiraz, Iran. It has an important role in biological control of carrier insects in the region. In this study on the biology of A. persicus, occurrence of Ligula intestinalis is described. Method & Materials: A total of 357 fish specimens were collected and examined for parasitic infection accordingly. Results & Conclusion: 173 specimens (48.5 %) were infected with L. intestinalis plerocercoids, a pseudophyllidean cestode which in its plerocercoid stage may infect a wide range of freshwater fish species. These plerocercoids were coiled around the viscera and occluded the body cavity of infected fish. The highest infection rate was in May and April resembling 141 and 112 parasites respectively followed by 78 parasites in October. Maximum number of observed parasites in an individual fish was 18 in April. In December, infected fish did not have more than one plerocercoid and 4 fish out of 30 showed infection. The prevalence of the plerocercoid infestation decreased with increasing fish size. The parasite is distributed over the whole months with the highest abundance and intensity in May while the prevalence was highest in February. Ligula intestinalis plerocercoids may normally be expected to have a negative impact on A. persicus population by damaging the viscera specially by affecting the somatic gonadal growth. In this study the parasite-host relationships between the fish length, body weight and time of the year to infestation with L. intestinalis were investigated.

کلیدواژه ها:

Aphanius persicus ، Ligula intestinalis ، plerocercoid ، population ، Maharlu Lake