The impact of hypomagnetic conditions and light deprivation on mitosis of germ cells and body length of prelarvae in roach (Rutilus rutilus L.)

AbstractThis study investigated the positioning behaviour of individual fish in small shoals of 2 and 10 roach, Rutilus rutilus. In pairs consisting of one small and one large fish with an average length difference of 10 mm, no difference was observed in the number of initiations of shoal movement between small and large fish. However, once both fish were moving, large fish took up the front position more frequently than small ones. A subsequent experiment showed that body length was positively correlated with swimming speed which could explain the leading position of large fish. In a second experiment, using pairs of size-matched fish we found that in moving shoals fish which had been deprived of food for 7 days were more likely to take up front positions than well-fed conspecifics. No difference, however, was observed in the frequency of initiations of shoal movement. A final experiment with pairs and shoals of 10 fish showed that fish in the front position (and in the front half of the shoal for shoals of 10 fish) were much more likely to obtain food particles than fish in other shoal positions when resources were limited. This could provide a functional explanation for the occurrence of food-deprived fish in front positions. Our results suggest that the initiation of new swimming directions in stationary shoals does not follow the same principles as positioning behaviour in shoals that are already on the move.

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SEASONAL CHANGES IN THE MICROSTRUCTURE OF EARLY STAGES OF OOGENESIS IN THE COMMON CARP (CYPRINUS CARPIO LINNAEUS, 1758) AND THE CASPIAN ROACH (RUTILUS RUTILUS CASPICUS JAKOWLEW, 1870) IN THE WEST COAST OF THE CASPIAN SEA

Herald of Daghestan Scientific Center of Russian Academy of Science ◽

10.31029/vestdnc74/3 ◽

2019 ◽

pp. 19-27

Author(s):

Ziyatdin Magomedzagirovich KURBANOV ◽

Umshanat Dzhamaldinovna ZURKHAEVA ◽

Ruslan Magomedovich BARKHALOV

Keyword(s):

Common Carp ◽

Germ Cells ◽

Seasonal Changes ◽

Microstructural Analysis ◽

Rutilus Rutilus ◽

Early Spring ◽

The Caspian Sea ◽

Roach Rutilus Rutilus ◽

The Common ◽

Caspian Roach

The work presents microstructural analysis of the oocytes of the common carp and the caspian roach that are on the stages of the protoplasmic and trophoplasmic (large) growth of the germ cells. Seasonal changes of quantitative and qualitative transformations of structural components of oocytes are also given. It is shown that from the early spring to the late autumn in the ovaries of the caspian roach and the common carp found are the oocytes of different generations, which are both at the generative and vegetative stages of growth of germ cells and along with this can occur, with varying intensity, resorption of whole oocytes and their individual structures. It has been established that spawning is common in the common carp, generative and regenerative processes occur simultaneously, while in the wobble spawning is simultaneous, the generative processes begin only after the regeneration of the sexual gland.

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The linear growth of roach infected with Ligula Intestinalis plerocercoids in the Chivyrkuysky Bay of the lake Baikal

Russian Journal of Parasitology ◽

10.12737/21654 ◽

2016 ◽

Vol 3 (3) ◽

pp. 312-318

Author(s):

Дугаров ◽

Zh. Dugarov ◽

Ринчинов ◽

Z. Rinchinov

Keyword(s):

Body Length ◽

Lake Baikal ◽

Linear Growth ◽

Age Groups ◽

Rutilus Rutilus ◽

Time Interval ◽

Age Classes ◽

Infection Level ◽

Roach Rutilus Rutilus ◽

Ligula Intestinalis

Objective of research: The purpose of the study is to investigate the influence of Ligula intestinalis plerocercoids on linear growth of roach Rutilus rutilus in the Chivyrkuysky bay of the lake Baikal. Materials and methods. Roach was caught on a permanent station in the Monakhovo creek of Chivyrkuysky bay of the lake Baikal at the same time interval (June 25-July 5) in 1997-2005. The analysis of roach infection with L. intestinalis plerocercoids was performed based on incomplete parasitological dissections of 807 host specimens at the age of 0+ to 10+. Standard body length (the distance from the tip of the snout to the anterior end of the caudal fin) was used to characterize the linear growth of roach. Results and discussion. L. intestinalis plerocercoids wasn’t found out in underyearlings (0+) of roach. The host began to be infected with this tapeworm at the age of 1+. The maximum infection level with L. intestinalis plerocercoids was observed in roach at the age of 3+. That one was significantly reduced in the age of 4+. The infection level of roach with L. intestinalis continued to decrease in the next age groups, going down to a minimum at the age of 7+. The roach wasn’t infected with this tapeworm at the age of 8+–10+. A significant reduction of the infection level in the roach in the age classes 4+ and older after the maximum at the age of 3+ was probably associated with parasite-induced mortality of the host during the growth of the age group 3+ to 4+. A standard body length of roach specimens infected with L. intestinalis at the age of 1+ and 2+ was greater than that of uninfected ones. In contrast, the standard body length of the roach specimens infected with this tapeworm was less than that of uninfected ones in subsequent age classes (3 + -6 +). Differences of standard body length between roach specimens infected with L. intestinalis and uninfected ones were statistically significant in the above-mentioned age groups (1 + 6 +). The effect of L. intestinalis plerocercoids on the linear growth of the roach in Chivyrkuysky Bay of the lake Baikal was manifested in an increase of body length of infected host specimens compared to uninfected ones in young age groups (1+ and 2+) and, vice versa, in one’s decrease in age groups 3+–6 +. We proposed to call this effect “reversive”.

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On the impact of low concentrations of chlorophos in the period of early ontogenesis on digestive carbohydrases of underyearlings of roach Rutilus rutilus

Journal of Ichthyology ◽

10.1134/s0032945206050079 ◽

2006 ◽

Vol 46 (5) ◽

pp. 404-408 ◽

Cited By ~ 9

Author(s):

I. L. Golovanova ◽

M. G. Talikina

Keyword(s):

Rutilus Rutilus ◽

Early Ontogenesis ◽

Roach Rutilus Rutilus ◽

Low Concentrations ◽

The Impact

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Influence of an extreme climatic event on bilateral asymmetry and occurrence of eye flukes in perch (Perca fluviatilis) and roach (Rutilus rutilus) from a lake in southeast England

Journal of Helminthology ◽

10.1017/s0022149x19000506 ◽

2019 ◽

Vol 94 ◽

Author(s):

N.J. Morley ◽

J.W. Lewis

Keyword(s):

Perca Fluviatilis ◽

Rutilus Rutilus ◽

Trematode Species ◽

Roach Rutilus Rutilus ◽

Bilateral Asymmetry ◽

Drought Period ◽

Extreme Climatic Event ◽

Climatic Event ◽

The Impact ◽

Eye Fluke

Abstract Eye flukes are common infections of freshwater fish and their occurrence as metacercarial stages may occur non-randomly resulting in an asymmetrical distribution within the host eyes. However, from previous studies the presentation of bias by these trematodes lacks consistency suggesting that congenital asymmetrical effects are unlikely to be the cause and exogenous factors, such as environmental stress, may be more influential. The present study, undertaken over a 4-year period, investigates the impact of an extreme heatwave and drought on the annual bilateral asymmetry and occurrence of two eye fluke species (Diplostomum sp. in the lens and Tylodelphys sp. in the vitreous humour) from perch (Perca fluviatilis) and roach (Rutilus rutilus). The onset of the extreme climatic event resulted in a significant negative effect on the occurrence of the eye flukes. Bilateral asymmetry, which was present within both trematode species and hosts, appeared to be highly variable between eye fluke and fish species and also year of study. However, during the pre-drought period both host species demonstrated significant asymmetry for Tylodelphys sp. but not for Diplostomum sp. while during the drought this bias was reversed. The potential role of fluctuating asymmetry of fish hosts in structuring the bilateral asymmetry of eye flukes is discussed.

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