Features of embryo and morphogenesis trichurise eggs of cattle in vitro

Abstract

One of the main factors hampering the development of livestock is the proliferation of a large number of diseases, both contagious and non-contagious etiology. Parasitic diseases of cattle and, in the first place, helminthiasis occupy a significant proportion of the diseases of contagious etiology. The dominant position among the helminthiasis of the digestive organs in ruminants is nematodosis of the gastrointestinal tract, in particular trichyrosis, the economic losses of which consist of a decrease in the productivity of animals due to the development of inflammatory processes in the thick intestine. Trihuris are geoellimits, which are localized predominantly in the blind and colon of the gastrointestinal tract. Females of the parasite lay eggs, which, with fecal animals, are released into the environment, where they are formed and reaches the invasive stage of the larva. Terms of preinvasive development depend on temperature. At a temperature of 30 ° in the eggs of T. ovis, the larva is formed after 17 days, and at 13–17 ° – after 118 days. At 10 º and below, the development of eggs is suspended, but they remain viable for several months. At temperatures above 38 ° the eggs die. According to U. A. Magometbekova (1953), in eggs of T. skrjabini, which parasitized in sheep, at 25–30 ° an invasive larva can be detected in 44–46 days after the eggs enter the environment. Eggs are bad for drying. The results of cultivation of eggs of T. skrjabini, the females of which parasitized in cattle, in vitro at a temperature of 27 ° for 51 days are given. The features of embryo and morphogenesis of eggs of pathogens during cultivation were studied. From the thick intestine of young cattle, by the method of a complete helminthological section by K.I. Scriabin, sexually mature nematodes were isolated, from which female gonads received immature eggs that were cultivated. It was found that at temperatures of 27 °C eggs T. skrjabini, parasitized in the thick intestine of cattle, pass into the stage of invasive larvae from the 27th day and completely stop their development to 51 days. During the period of cultivation, the length of eggs and caps is increased by 2.0 and 20.0%, the width of eggs and caps is reduced by 2.3 and 3.9%, compared to the cultivars. Reduced egg shell thickness by the 27th day of cultivation (by 2.1%) with a subsequent cessation of changes in this index.