Some Aspects of Development and Histological Structure of the Visual System of Nothobranchius Guentheri

Abstract

In this, work some aspects of the development of the visual system of Nothobranchius guentheri at the main stages of ontogenesis were described for the first time. It was possible to establish that the formation of the visual system occurs similarly to other representatives of the order Cyprinodontiformes, but significantly differs in terms of the individual stages of embryogenesis due to the presence of diapause. In the postembryonic period, there is a further increase in the size of the fish’s eyes and head, to the proportions characteristic of adult fish. The histological structure of the eye in adult N. guentheri practically does not differ from most teleost fish living in the same environmental conditions. The study of the structure of the retina showed the heterogeneity of the thickness of the temporal and nasal areas, which indicates the predominant role of peripheral vision. Morphoanatomical measurements of the body and eyes of N. guentheri showed that their correlation was conservative. This indicates an important role of the visual system for the survival of fish in natural conditions, both for the young and adults. In individuals of the older age group, a decrease in the amount of sodium (Na) and an increase in magnesium (Mg) and calcium (Ca) were found in the eye lens. Such changes in the elemental composition of the lens can be a sign of the initial stage of cataractogenesis and disturbances in the metabolism of lens fibers as a result of aging. This allows us to propose N. guentheri as a model for studying the structure, formation, and aging of the visual and nervous systems.

Neurotrophins and Trk Neurotrophin Receptors in the Retina of Adult Killifish (Nothobranchius guentheri)

“…The visual system of vertebrates supports interaction with the environment and is crucial for vital processes such as reproduction, migration, food search, and physical activity [ 1 ]. In both mammals and fish, visual system performance relies on specialized cells [ 2 ] under the control of neurotrophins (NTs) and their specific receptors.…”

New insights into the retinal microstructure-diurnal activity relationship in the African five-lined skink (Trachylepis quinquetaeniata) (Lichtenstein, 1823)

“…Their retinae are usually devoid of rods and are distinguished by centrally located foveae. Iguanids, chameleonids, agamids, scincids, lacertids, anguids, pygopodids, and varanids appear to have pure-cone retinae [4,23,24]. The morphology of the retinae of most reptilian groups, particularly lizards, is unknown, as it is in other vertebrates, birds, and mammals [25].…”

Evaluation of Age-Dependent Changes in the Coloration of Male Killifish Nothobranchius Guentheri Using New Photoprocessing Methods

“…Nothobranchiidae are short-lived, relatively easy to husbandry, transgenetic methods and genome sequencing have been determined, and they are much cheaper to keep than laboratory mice [ 5 ]. As such, representatives of this family are a convenient object for studying the processes of evolution, development, and aging [ 6 , 7 , 8 , 9 , 10 ].…”

“…Among these species, N. rachovii has the shortest life cycle (5−6 months) but has one of the longest embryonic development durations (8−9 months), which makes its cultivation in laboratory conditions difficult. In contrast, N. guentheri has a longer life span and short embryonic diapause, which means that synchronized cultures can be obtained for research [ 8 ]. Representatives of the genus Nothobranchius are characterized by a high diversity of karyotypes, which, perhaps, plays an important role in their adaptation to unstable environmental conditions [ 16 ].…”