Water hardness influenced variations in reproductive potential of two freshwater fish species; Poecilia reticulata and B
- PDF / 1,015,291 Bytes
- 6 Pages / 595.276 x 790.866 pts Page_size
- 42 Downloads / 180 Views
(2020) 13:542 Krishnakumar et al. BMC Res Notes https://doi.org/10.1186/s13104-020-05382-x
Open Access
RESEARCH NOTE
Water hardness influenced variations in reproductive potential of two freshwater fish species; Poecilia reticulata and Betta splendens Abarna Krishnakumar1, E. S. Patrick Anton1 and Uthpala A. Jayawardena2*
Abstract Objective: Hardness of water in the form of CaCO3 affects reproductive potential in various fish species, differently. This study evaluates the effect of water hardness on growth and reproduction of two aquarium fishes, Poecilia reticulata (Ovo-viviparous sp.) and Betta splendens (Oviparous sp.) by growing them under 150 (control), 320, 540 and 900 ppm CaCO3 levels in semi natural aquaria. Results: Growth increased with increasing water hardness, reporting a significant progress of P. reticulata (p = 0.005) at 900 ppm. Similarly, the reproductive potential of P. reticulata was improved significantly, recording the highest fecundity (16.22 ± 3.90) and Gonadosomatic Index (GSI-2.48 ± 0.6) at 900 ppm. However, in B. splendens water hardness adversely affected the reproduction by resulting a significantly low hatchability and disturbed bubble nests at 900 ppm, compared to the largest bubble nest formed at the control condition (108.58 ± 16.19 cm2). Thus, the study revealed differential effects of water hardness on reproductive potential of the test species, by increasing the potential of P. reticulata while decreasing that of B. splendens. Though larval survival was affected in both species, larval growth was improved significantly in P. reticulata at 900 ppm level. Understanding reproductive potential of aquarium fishes in natural waters is crucial for their management purposes. Keywords: Water hardness, Freshwater fish, Fecundity, Gonadosomatic index, Growth performance Introduction Water hardness i.e., a measure of calcium (Ca2+), magnesium (Mg2+) and/or iron ( Fe2+) in water, is crucial for the growth, reproduction and embryo development of fish [1–4]. It affects oviparous and ovoviviparous fishes differently due to variations in their requirement of CaCO3 in the reproduction and growth [1, 5–8]. Considering the importance of hardness in the early life stage processes such as hatchability, larval growth and survival of eggs, it is recommended to maintain the water hardness above 20 ppm CaCO3 [9, 10]. *Correspondence: [email protected] 2 Department of Zoology, Faculty of Natural Sciences, The Open University of Sri Lanka, Colombo, Sri Lanka Full list of author information is available at the end of the article
Water hardness in Vavuniya District, of the Dry Zone of Sri Lanka reports remarkably high values, such as 900–1000 ppm [11]. In Vavuniya, ornamental fish trade is mainly dependent on ground water. Thus, evaluating the effect of higher hardness on fish health is of prime economic and ecological importance. Freshwater species, Poecillia reticulata (Guppy) and Betta splendens (Siamese fighting fish) were popular verities in the aquarium fish trade. P. reticulta produces
Data Loading...
