Abstract
The aim of this research was to study the dynamics of metabolism in the body of bream Abramis brama (L.) at different periods of the annual cycle: pre-spawning, spawning, post-spawning and feeding. The object of the study was 55 male and 53 female bream aged 9–13 years, to reduce the effect of age on the studied parameters. Individuals were measured, weighed, gender was determined, gonad maturity stage, age; the condition factor and organ indices were calculated. The content of moisture, dry matter, lipids, proteins, ash and nitrogen-free extracts (NFE) in the muscles, liver and gonads of male and female bream have been analyzed. The lowest coefficients of condition factor were found in bream during the autumn feeding season, the highest in males during spawning, in females before and after spawning. In the muscle tissue of male and female bream the content of metabolic products in the feeding period and before spawning differed slightly. In the spawning period, the muscles of males exceeded the muscle tissue of females in lipid content by more than two times. In the annual cycle of the bream, the ovaries contain more protein than the testes. The bream of different sex revealed differences in the intensity of metabolic processes during the maturation of gonads: in males, energy costs are more pronounced after wintering before spawning, while in females, during spawning. The main energy reserve in the form of lipids in the annual cycle changes more significantly in the body of male bream than in females. Ovarian maturation requires more metabolite reserves than maturation of the testes, however, males have increased expenditure associated with reproductive behaviour during spawning. Therefore, the total energy contribution to reproduction may be the same for female and for male bream. Bream’s liver and muscle tissue can serve as a source of energy during food shortages and during spawning. In the annual cycle, the condition factor of bream increases due to an increase in the moisture content in the muscles.
Highlights
IntroductionOver the course of a year, populations of animals, including fish, undergo qualitatively different specific stable states called the periods of the annual cycle, which start depending on the environmental factors (length of daylight hours, temperature, dry or wet season) (Shulman & Love, 1999; Wootton & Smith, 2015; Marenkov, 2018; Soyano & Mushirobira, 2018)
Over the course of a year, populations of animals, including fish, undergo qualitatively different specific stable states called the periods of the annual cycle, which start depending on the environmental factors (Shulman & Love, 1999; Wootton & Smith, 2015; Marenkov, 2018; Soyano & Mushirobira, 2018)
The lowest fatness coefficients were observed in bream during the autumn feeding, the highest in males – during spawning, in females – before the spawning according to Fulton, and in the post-spawning period according to Clark (Table 2)
Summary
Over the course of a year, populations of animals, including fish, undergo qualitatively different specific stable states called the periods of the annual cycle, which start depending on the environmental factors (length of daylight hours, temperature, dry or wet season) (Shulman & Love, 1999; Wootton & Smith, 2015; Marenkov, 2018; Soyano & Mushirobira, 2018). In the process of distribution of the energy in the body of fish in different periods of the annual cycle, fats, proteins, mineral substances and other components perform various functions (Bilokon et al, 2013; Zarubin et al, 2013; do Carmo Silva et al, 2019). During the evaluation of physiological condition of fish in different periods of the annual cycle, it is important to have data on the dynamics of the content of the metabolism products in the muscles and the organs. The study of the biochemical changes in the organism of hydrobionts in the pre-spawning and spawning periods allows more complete revelation of the process of reproduction and prediction of the terms and duration of the spawning, and the productivity of individuals (Krivobok & Tarkovskaya, 1960; Rajasilta, 1992). The dynamics of accumulation of products of metabolism in the organism of common bream in different periods of annual cycle require separate and comprehensive analysis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
