HISTOLOGICAL CHANGES IN THE STRUCTURE OF THE REPRODUCTIVE SYSTEM OF DRONES UNDER THE CONDITIONS OF CONTAMINATION WITH THE AMERICAN ROT (PAENIBACILLUS LARVAE)

Abstract

The developmental anatomy and histological studies of the reproductive system of both insects in general and honey bee drones in particular have been fairly well documented by earlier scientists. It is known that the reproductive system was described by the scientist Jan Swammerdam in his own posthumous publication back in the 18th century, where it was written that the reproductive organs consist of paired gonads, conducting ducts and tubules, some additional gonads and the endophallus itself. Scientists such as Zander, Bishop, and Snodgress described the anatomical feature of the development of drone testes at the larval stage and their histological structure, and in 2020, the scientist Lago described a more detailed atlas according to the process of spermatogenesis and the actual development of drone testes before they emerge from cells It should be noted that the functional units of the testes of drones are actually the tubules of the testicles, they are also called testicular follicles or even spermatozoa. It is known that actually hundreds of tubules enter the vas deferens through anatomically located individual seminiferous tubules, which in turn pass together with the basilar tubule and pass to the apical tubule, actually to the periphery of the testicle. But the study of normal histology does not give a complete picture of the development of the drone's reproductive system. As a rule, they are not sufficiently well described in literary sources. It should be noted that the influence of various types of bee diseases on the development of the reproductive system of the drone is not described in the literature. The article describes the main phases of changes in tissues during puberty under conditions of contamination with American rot. Histological changes of the testicle during maturation are characterized by the following main consecutive phases: the first phase is characterized by the completion of spermiogenesis, the second phase is the exit of spermatozoa into the lumen of the tubes, the next third phase shows the corresponding progressive atrophy of follicular cells and the last phase itself – complete atrophy and, accordingly, collapse. Tubular changes occur in a basilar to apical direction, with segments closer to the vas deferens being histologically more mature than the corresponding apical segments. In addition, it should be noted that the peculiar rate of development of maturation of reproductive organs can change with seasonal progression. This study of the progressive atrophy of the reproductive system of the drone can be useful for future breeders, as the histological study shows the result of contamination with the causative agent of rotting disease, which actually has negative results and can affect the breeding performance of the bee colony.