Analysis of Several Indicators of Infection from Gyrodactylus spp. in one Year Rainbow Trout (Oncorhynchus Mykiss)

In this study are analyzed the dynamics of infection of rainbow trout from Gyrodactylus spp. one of most important fish parasite. We have proven the gradual increase of infection values from the first week of infection until the fourth week (the week with the highest number of parasites). The values of week five and six presented a reduction of parasites number. Comparing the values of parasites number (F%) in 12 areas of fish we can conclude that the most affected areas in the beginning of the infection were pectoral fins (F% = 46.2) and the abdominal fins (F% = 22.7%). Caudal fin showed a number of parasites value F = 9.6%. In the end of the period of the study (week six), compared with the beginning of the infection, the number of the parasites localized in the fins was reduced by 3.7 times, in the anal fin 3:09 times and abdominal fins for about 1.79 times. A different situation resulted for caudal fin and the cornea that after the six week showed a increase of the parasite number respectively 2.28 and 21.1 times. In this study is proved a negative correlation between the density of mucosal cells (Dcell / 0.6mm²) in a specific area of the tail.