Effect of Temperature on the Survival Rates of the Embryonic States of Development of Trichuris skrjabini Nematodes Parasitizing Sheep

The prevention of the trichurosis of sheep requires understanding the terms of development of pathogens and their survival in the environment under the influence of abiotic factors. This study was conducted to deter-mine the tolerance to a temperature factor of Trichuris skrjabini nematode eggs isolated from sheep. Trichuris eggs were obtained from the gonads of female nematodes in laboratory conditions and cultivated in a thermos-tat until the appearance of motile larvae in the eggs at the temperatures of 20 & DEG;C, 25 & DEG;C, and 30 & DEG;C. It was determined that the time of formation of infectious eggs decreases with increasing temperature. The temperature of 25 & DEG;C was found to be the most favorable for the development of T. skrjabini eggs in laboratory conditions, and 80.3% of eggs with motile larvae formed on the 54th day. Temperatures of 20 & DEG;C and 30 & DEG;C were less advantageous to the process of embryogenesis. The motile larvae develop in eggs in 63 days at 20 & DEG;C and in 45 days at 30 & DEG;C, and their respective survival rates are 77.0% and 75.3%. The obtained data increase the effectiveness of plan-ning measures to prevent the trichurosis of sheep, taking into account the period of development of the pathogen depending on the temperature of the environment.