THE OPTIMIZATION AND APPLIED ADAPTATION OF THE HISTOLOGICAL TECHNIQUE FOR SPECIES IDENTIFICATION OF TREMATODES OF THE FAMILY PARAMPHISTOMIDAE FISCHOEDER, 1901

We studied 200 samples of histological microslides of paramphistomid species Paramphistomum ichikawai Fukui, 1922 from cattle and sheep, from the Parasite Collection of the VNIIP – FSC VIEV. Of these, only 15 slides (7.7%) had morphologically informative medial sagittal histological sections ("M.S.H.S.") in their series. One hundred and eighty-five P. ichikawai slides (92.3%) did not have morphological informative value which is formalized by the regulations for the histological species diagnosis of parasites. Only 49 specimens (1.28%) out of 3,815 specimens from the total number of histological sections of the P. ichikawai body placed on 200 sample slides fully corresponded to the trematode M.S.H.S. status. The reasons for the low information quality of histological P. ichikawai sections were errors in the equipment selection and configuration for specialized histological work with paramphistomids, and the lack of applied methodological techniques that consider natural morphology of trematodes. An optimized technology has been developed which, as a priority condition, solves the problem of organizing visual control, both direct and with light microscopic optics, over the coordinated spatial location of the trematode in the paraffin embedding and in the production of histological MS-2 microtome sections. The main objective of optimization and applied adaptation of histological technology is to ensure practical possibility of obtaining morphologically informative M.S.H.S. from each specimen of paramphistomids that are necessary for species diagnosis of taxon representatives.