Abstract
The ricefield eel (Monopterus albus) is an economic fish species in China. To improve its artificial reproduction, we studied the compositions and functions of the hatching froth secreted by ricefield eels. The froth showed a viscosity of 2.72 mPaS, composed of glycoproteins with a sugar content of 0.156 mg/ml and a protein content of 0.250 mg/ml at a ratio of 1.60. The froth proteins were identified by SDS-PAGE as four proteins with the molecular weights of 42.5, 58.6, 65.3, and 98.2 kDa respectively. Their total amino acid content was 201.88 mg/100 ml, consisting of 16 kinds of amino acids. Filed observation revealed three beneficial effects of the froth on the hatching of the eel eggs. First, the froth increased the hatching rates of fertilized eggs at a range of water temperatures. Second, the froth decreased the rates of infection of the fertilized eggs by the water mold. Finally, the froth accelerated velum breakage in the fertilized eggs. Of the different hatching methods, froth incubation achieved the highest hatching rate and larvae survival rate. These results demonstrate the indispensable function of the froth of ricefield eels, and offer practical reasons for protecting the froth during the breeding season.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Chan STH (1996) Biopsy studies on the natural sex reversal in Monopterus albus. J Zool (Lond) 167:415–421
Guan RZ, Zhou LH, Gui GH et al (1996) Studies on the artificial propagation of Monopterus albus. Aquac Res 27(28):587–596. doi:10.1111/j.1365-2109.1996.tb01291.x
Han MZH, Bai LP, Shi YB et al (1988) Study on artificial propagation of Monopterus albus. J Aquac 1:1–4 (in Chinese)
Liem KE (1963) Sex reversal as a natural process in the synbranchiform fish Monopterus albus. Copeia 2:303–312. doi:10.2307/1441348
Li JW (2000) The experiment elements and methods of biochemistry. Beijing University Press, Beijing (in Chinese)
Liu CK, Ku KY (1951) Histological changes in the gonad of Monopterus during sex transformation. Acta Hydrobiol Sin 2(1–2):85–109 (in Chinese)
Tao YX, Lin HR (1991) Studies on the natural sex reversal of paddyfield eel (Monopterus albus). Acta Hydrobiol Sin 15(3):274–278 (in Chinese)
Xiao YM (1993) Study on the reproductive biology of Monopterus albus. I. Early gonadogenesis and structure change Monopterus albus. Acta Sci Nat Univ Norm Hunan 16(4):346–349 (in Chinese)
Xiao YM, Liu Y (1995) Study on the histology in sex changing from intersex to male of Monopterus albus. J Fish China 19(4):297–301 (in Chinese)
Yeung WSB, Chen H, Chan STH (1993) The in vitro metabolism of radioactive androstenedione and testosterone by the gonads of the protogynous Monopterus albus different sexual phases: a time-course and seasonal study. Gen Comp Endocrinol 89(3):313–322. doi:10.1006/gcen.1993.1039
Zhang WJ (1999) The biochemical research technology of glycoconjugates. Zhejiang University Press, Hangzhou (in Chinese)
Zhou GJ (1994) The breeding of special aquaculture. Hunan Science and Technology Press, Changsha (in Chinese)
Zou JX (1996) Artificial propagation and embryonic development of Monopterus albus. Technol Inf 23(1):27–30 (in Chinese)
Acknowledgements
We wish to thank Professor H.R. Lin of Sun Yat-Sen University of Guangdong, China, for his helpful comments.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Yin, S., Liu, Y. Compositions and functions of the hatching froth from ricefield eel (Monopterus albus Zuiew). Fish Physiol Biochem 36, 195–200 (2010). https://doi.org/10.1007/s10695-008-9274-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10695-008-9274-6