Comparative effectiveness of coproovoscopic methods for the diagnosis of mono- and mixed invasions of the digestive tract in dogs

The most accurate methods for intravital diagnosis of gastrointestinal helminthiases in dogs are laboratory examinations, which include various flotation, combined, qualitative, and quantitative coproovoscopic techniques that differ in diagnostic effectiveness depending on the parasitic disease. The aim of the study was to determine the sensitivity of coproovoscopic methods for diagnosing trichurosis monoinvasion and mixed invasions in dogs, involving Trichuris, Dipylidium, and Cystoisospora as co-members. The studies were conducted at the private veterinary clinic “Dovira” in Kharkiv and at the Laboratory of Parasitology of Poltava State Agrarian University in Poltava. The flotation methods of Kotelnikov–Khrenov, using an ammonium nitrate solution; Sorokova, using a combined solution of calcium and ammonium nitrate; Petrenko, using a combined solution of calcium nitrate, sugar, and sodium chloride; and Melnychuk, using a combined solution of calcium nitrate and sodium chloride, were tested in the diagnosis of mono- and mixed invasions. It was established that the sensitivity of the tested methods for detecting Trichuris eggs and Cystoisospora oocysts was 100 %. In detecting Dipylidium egg capsules as components of mixed invasions, the Melnychuk method showed the highest results, with sensitivity ranging from 86.7 to 100 %. The Petrenko, Sorokova, and Kotelnikov–Khrenov methods demonstrated lower sensitivity, namely 73.3–93.3 %, 53.3–80 %, and 46.7–73.1 %, respectively. The diagnostic effectiveness of the methods varied depending on the invasion intensity indicators. In cases of trichurosis monoinvasion and mixed invasions in dogs, the highest number of exogenous developmental stages of parasites was detected using the Melnychuk method. Its effectiveness exceeded that of the commonly used Kotelnikov–Khrenov method in detecting Trichuris vulpis eggs by 1.9–2.0 times, Dipylidium caninum egg capsules by 1.4–1.7 times, and Cystoisospora spp. oocysts by 1.8–2.3 times. The obtained results allow recommending the Melnychuk flotation method, using a combined solution of calcium nitrate and sodium chloride, for effective coproovoscopic diagnosis of trichurosis monoinvasion and mixed invasions in dogs involving the nematode T. vulpis, the cestode D. caninum, and coccidia of the genus Cystoisospora spp.