Impact of Sodium Chloride and Heat on Survival Time of Linguatula Serrata Nymphs in vitro: An Experimental Study

Linguatula serrata is a zoonotic parasite, belonging to the class Pentastomida. The major aim of this study was to evaluate the impact of sodium chloride (NaCl) and heat on survival time of Linguatula serrata nymphs. Thirty nymphs (10 in triplicate) were separately transferred to plastic tubes, containing different concentrations of NaCl solution (2%, 5% and 10%). Meanwhile, 30 nymphs in tubes containing Phosphate Buffer Saline (PBS) were separately treated by +50°C, +60°C and +72°C. As control group, thirty nymphs were stored in PBS at +4°C. The effects of different conditions on survival time of the nymphs were evaluated by observing their motility in different periods of time. The survival time of the nymphs stored in 10% NaCl solution was too short and all of them were dead after 3 hours. But the other ones maintained in 2% NaCl solution were significantly more resistant (p<0.05) and were survived for 2 days. All the nymphs pertaining to each +60°C and +72°C treatments were found dead after first 5-minute storage interval; the nymphs stored at +50°C died totally after 20 minutes. The nymphs maintained in PBS at +4°C (control group) showed the longest survival time (p<0.05); all of them were alive until day 4 and the last ones died on day 34. It is concluded that salting and heating have significant parasiticidal effects on L. serrata nymphs and could be used as disinfecting methods in processing of meat products especially liver. However, refrigeration at +4°C increases the resistance of the nymphs in meat products and therefore might endanger the food safety.