بررسي تاثير تزريق داخل صفاقي ترونت / يكتيوفتريوس مولتي فيليس بر آنتي بادي‌هاي سرمي ماهي قزل‌آلاي رنگين كمان‌

The effect of intraperitoneal injection of Ichthyophthirius multifiliis theront on serum antibodies in rainbow trout

Vaccination of rainbow trout against ciliate, Ichthyophthirius multifiliis, using live theront through intraperitoneal route (800 theront per fish) influenced humoral immunity against this parasite. Higher antibody titer in immobilisation assay and higher optical density in ELISA test were measured in vaccinated groups compared to controls. Although significant increase was reported in antibody level by immobilization assay or ELISA test 14 and 28 days post vaccination(DPV), there was no significant increase until 7 DPV. Temperature dependent antibody production against this parasite after vaccination was observed, so the mean and standard deviation (SD) of antibody levels measured with immobilization assay on 14 and 28 DPV in 12°C and 20°C were 36+32.32 , 34.67+22.46 and 46.67+42.17 , 46+42.86 respectively, whereas mean and SD of optical densities in 14 and 28 DPV were 0.168+0.085 , 0.1480.052 and 0.206+0.080, 0.205+0.096, respectively. Meanwhile, results showed that ELISA is more sensitive test than immobilization test to measure the antibody level against Ichthyophthirius multifiliis after vaccination. It may be due to the nonspecific humoral response which affected immobolisation test.