-

Objective: To compare the skin responses of infected and non-infected sheep with Linguatula serrate nymph.
Design: Experimental study.
Animals: Thirty native sheep.
Procedure: The nymphs of Linguatula were collected from mesenteric lymph nodes of slaughtered animals and the protein of nymphs was extracted. The extracted protein was injected at the dose of 0.2 ml intra-dermopalpebrally
into the skin of lower eyelid of sheep. A placebo was injected into the skin of contra lateral eyelid. The skin reaction was evaluated 1 hour after injection. Infection status of injected sheep was determined by demonstration
of Linguatula serrate nymphs in the mesenteric lymph
nodes after slaughter as gold standard.
Statistical analysis: Compute sensitivity, specificity, accuracy, positive and negative predictive values, likelihood ratio and kappa statistic of the intradermal skin test al a different cut off values.
Results: Our calculated measures of diagnostic performance of intradermal skin test of Linguatula serrate were lower than anticipated and those previously reported. Conclusion: Intradermal skin test can be used for detection
of non-infected sheep.