Probability description of regulation on the level of population and individual in the host-parasite system using Oestrus ovis (Diptera: Oestridae) as an example.

A scheme of a mixture of normal laws of weight distribution in Oestrus ovis L. larvae of various stages was used for the determination of their mortality and for the evaluation of basic distribution parameters. No mortality was observed in 2nd- and 3rd-stage larvae. The distribution of the number of 1st-stage larvae corresponds to the negative binomial law. The weight distribution correlates with the quantitative distribution of the 1st-stage larvae. The present studies are based on the results obtained during the investigations of ovine oestrosis in Stavropol Territory of the RSFSR and the Kalmyk ASSR performed by K.A. Breev and his coworkers in 1976-77.