Defining and comparison of biodiversity components of hard ticks on domestic hosts at Highland, Woodland and Plain in Northern Iran

@#The aim of the present study was to compare the biodiversity patterns of tick species in the Northern Iran between June 2007 and June 2008. 41 villages within three locations, viz. highland, woodland and plain, were selected using cluster randomized sampling method. A total of 504 sheep and 162 cattle visited monthly for a period of 12 months for the presence of ticks. Estimated richness was calculated using rarefaction curves and richness estimators. Defining the contribution of biodiversity components was adjusted using SHE analysis. A total of 1,231 hard ticks (consisting of 6 genera and 6 species) were collected. Rhipicephalus bursa (in highland and plain) and Boophilus annulatus (in woodland) were identified as eudominant species with the most abundance. Seasonal activity of the ticks varied among species. Rarefaction curves showed that summer and spring had the highest species diversity and richness in different locations. SHE analysis revealed that evenness had the greatest effect on the changes of species diversity and also showed that all regions are mainly occupied by common species. The study demonstrated that the seasonal fluctuations of R. bursa have a significant impact on the changes of species diversity.

Laboratory colonization of Lucilia sericata Meigen (Diptera: Caliphoridae) strain from Hashtgerd, Iran.

Background & objectives: The treatment of wounds with live green bottle fly larvae is receiving considerable attention in many countries. Laboratory rearing of Lucilia sericata is crucially important for the treatment of wounds. Study design: The study was carried out for mass rearing of green bottle flies from April to November 2010. Hand catch and net trap baited with beef and cattle liver were used to collect adult flies from the field. The collected samples were placed in appropriately labeled tubes and sent to the laboratory. Adult stage flies reared in the insectary were used for species identification using specific keys. Results: A total of 89 flies (55 females and 34 males) were collected from Hashtgerd area. In the first generation, 299 flies were produced in the laboratory including 105 (35.12%) males, and 194 (64.88%) females. The female/ male sex ratio was 1.61 for parents, whereas it was 1.84, 1.30 for F1 and F2 generations respectively. In total, 432 flies were reared in F3 generation including 173 (40.04%) males, and 259 (59.96%) females, and the sex ratio was 1.49. Conclusion: Setting up the mass rearing of sheep blowfly at the School of Public Health, Tehran University of Medical Sciences is an important step in producing candidate flies for the treatment of myiasis by maggot therapy in future.

Application of predictive degree day model for field development of sandfly vectors of visceral leishmaniasis in northwest of Iran.

Background & objectives: Temperature plays a significant role in insect’s development where a rise in temperature, accelerates the insect’s metabolic rates, increases egg production and makes blood feeding more frequent. It also shortens the time period required for the development of pathogens within insects. Visceral leishmaniasis (VL) is one of the most important vector-borne diseases transmitted by different sandfly species. In this study, a phenological model was used to estimate the number of generations, peak activity and temporal variability of sandflies in the main VL foci in northwest Iran. Methods: Development requirements of different life stages of a Phlebotomus papatasi laboratory colony were measured and were subjected to the formula for calculation of accumulated degree day (ADD) for field sandflies using the online soft (UC IPM), using horizontal cut-off method and single triangle model. Sandflies population dynamics was monitored in the field during the seasonal activity in the region and its association with the ADD was tested using SAS software. Results: Populations of sandflies accommodated well with the amount of accumulated degree days (ADD) in the region. During the seasonal activity, a total of 639 ADD were produced which was enough to support one complete life cycle and growth of the next generation up to late larval instar. Larvae of the second generation hibernate through winter and the first adult population appears in the mid to late June of the next year when they receive at least 182 ADD from the beginning of the spring. The highest population density of sandflies was observed in early August, followed by a rapid decrease in early September, with the adult population disappearing completely in late September. This is the first degree day model related to sandflies in the most important VL foci of Iran. Interpretation & conclusion: Further studies in various regions with variable climate are recommended in order to better estimate and understand the development time, population dynamics and activities of the vectors which in turn could be used in proper implementation of effective vector control programmes.