Histopathological Findings in Testes from Apparently Healthy Drones of Apis mellifera ligustica

Abstract

It is well known that factors acting on the decrease of population of honeybees, can act on the male and female reproductive system, compromising the fertility of queens and drones. While there are many studies on female fertility, only a few studies have focused on male fertility and the possible alterations of the reproductive system. The testes of 25 samples of adult drones of Apis mellifera ligustica were analyzed by histopathology using an innovative histological processing technique and the alterations that were found are here described. Most of the samples showed unaltered testes but, in some cases, samples showed degenerated seminiferous tubules, while others appeared immature. Although a limited number of samples were analyzed, the results obtained displayed that histopathological alterations of the testes exist also in honeybees and that more interest should be put to the matter, as honeybees could be considered as bioindicators for endocrine disruptors. Future studies on a larger number of samples are necessary to analyze how different environmental factors can act and induce alterations in the honeybee reproductive system.

Testicular Changes of Honey Bee Drones,Apis mellifera(Hymenoptera: Apidae), During Sexual Maturation

“…Power et al ( Power et al 2020 ) recently published an investigation of histopathological changes in testes of 25 free-flying healthy drones, the age of which was estimated according to whole-body mass ( Metz and Tarpy 2019 ). Based on microscopic evaluation, 17/25 drones had normal testicular parenchyma with germ cells within follicular cells and spermatodesms in tubular lumens which correspond to histological Stages I and II, respectively, described in the current study.…”

“…They also observed degeneration and necrosis of follicular and germ cells within seminiferous (testicular) tubule of 5/25 drones and delayed or incomplete maturation of germ cells in 2/25 drones. Interestingly, Power et al ( Power et al 2020 ) also indicated that an experimental histopathological study describing testicular changes during sexual maturation of drones was lacking. The current study fills this gap, and the detailed histological description of testicular changes will enable differentiation of normal atrophic processes occurring during sexual maturation from pathological processes described by Power et al ( Power et al 2020 ).…”

“…Individual testicular tubules are surrounded by an inner peritoneal sheath ( Lago et al 2020 ) that contains follicular cells ( Da Cruz-Landim et al 1980 , Power et al 2020 ) [also called nutritive ( Moors et al 2009 ), or cyst cells ( Snodgrass and Morse 1956 , Cruz-Landim 2001 ]), which house and support the developing gametes in specialized intracellular cavities ( Snodgrass 1935 ). The entire testis is also surrounded by a peritoneal sheath ( Snodgrass 1935 ) [or testicular capsule ( Forbes 1954 , Kapil 1962 )].…”

Honey Bee Health

“…Power et al found an innovative histological processing technique to analyse healthy drones of A. mellifera ligustica. The new approach can detect testes alterations, such as degenerated seminiferous tubules [ 21 ].…”

Histopathological Features of Symptomatic and Asymptomatic Honeybees Naturally Infected by Deformed Wing Virus

“…Samples were processed as previously described [ 69 ]. Briefly, honeybees were individually injected with 10 μL of 10% buffered formalin and then stored for 24 h in 50 mL tubes containing the same fixative.…”