Effect of disinfectants on viability of Trichuris skrjabini eggs

Abstract

The nematodoses are considered the most numerous group of cosmopolitan diseases among animal and human parasitoses. The representatives of the genus Trichuris attract special attention as pathogens of nematodoses. Their high fecundity, resistance to the influence of environmental factors and the ability to disperse create a serious ecological hazard and the risk of new outbreaks of infestation. The aim of the research was to establish the ovicidal efficiency of modern disinfectants on the embryogenesis of eggs of Trichuris skrjabini nematodes isolated from sheep. In laboratory conditions, two preparations were tested, DZPT-2 (mixture of glutaraldehyde, sodium dodecyl sulfate, essential oil) and Dixclor (mixture of sodium bisulfate, sodium chlorite, sodium percarbonate) at different concentrations and times of exposure. We established that DZPT-2 disinfectant showed a high level of ovicidal efficiency (97.5–100%) against T. skrjabini eggs at 4.5% concentration during exposure for 6–12 h and 5.0% concentration during exposure for 3–12 h. Dixclor showed a high level of ovicidal efficiency (100%) against Trichuris eggs at a concentration of 0.24% for exposures of 12 and 24 hours. Decreasing the concentration of disinfectants reduced the level of their ovicidal efficiency and led to the development of a greater number of viable eggs of T. skrjabini. Degenerative changes in the test cultures of T. skrjabini eggs caused by the tested disinfectants were characterized by the appearance and accumulation of air bubbles under the egg shell, the cessation of embryonic development at the bean-like embryo stage, loosening and resorption of the embryo inside the eggs, thinning and destruction of their shell, deformation of the eggs, and swelling of the egg plugs. Such destructive changes in eggs in experimental test cultures were also confirmed by the indicators of their morphometric parameters. Under the influence of DZPT-2 and Dixclor on the 54th day of cultivation, the length of the eggs was lower by 3.9%, and their width was greater by 4.8–5.1% compared to similar indicators in the control test culture. The obtained results allow one to recommend the tested disinfectants in defined and effective concentrations and exposures for effective control and prevention of trichurosis on livestock farms.