Effect of artificial diets on the growth and survival of rotifers

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1 BIOLOGIA (PAKISTAN) 2010, 56 (1&2), PK ISSN Effect of artificial diets on the growth and survival of rotifers ABDUL QAYYUM KHAN SULEHRIA, IFFAT YOUNUS & ALTAF HUSSAIN Department of Zoology, GC University, Kachery Road, Lahore, Pakistan. ABSTRACT The aim of present study was to culture the rotifers in laboratory on different combinations of artificial diet media i.e., Baker s yeast, starch and albumen. Rotifers were collected from Manawa ponds and cultured on six different combinations of diet media. Experiment was carried out at room temperature and continued for six days. Different parameters were determined and maintained during experiment and these were ph, Temperature, Count of rotifers and in biomass. Results showed that, among these six diet media, the rotifer number increased in those media which contained either starch or a combination of starch with other media. Statistical analysis showed the significant difference in rotifer count among these diet media. Keywords: rotifers, yeast, rotifer diets, rotifer culture INTRODUCTION Zooplanktons plays important function in the food chain as animal food, which is a source of amino acids, fatty acids, vitamins, minerals, etc. (Watanabe et al., 1983). It has been attempted to substitute live food by commercial diets, to rear fry and juvenile of fishes in hatcheries, however, it still depends on the adequate supply of zooplanktons (Habib et al., 1988). The use of the proper food for fry and juvenile stages is essential for proficient and economical hatchery techniques. Generally, rotifers have ample nutrient content and a high rate of reproduction (Lubzens, 1987). The rotifers serve as the first food to fish fry and other organisms during first few days after hatching (Lubzens et al., 2001). Rotifers provide essential nutrients, vitamins and even antibodies to fish fry (Gastesoupe, 1982). The amount of fatty acid in rotifer is thought to control both survival and growth rate of fish larvae (Koven et al., 1990). The culture of freshwater fish fry requires a suitable food source, such as living rotifers. In freshwater aquaculture, Brachionus calyciflorus. B. patulus and B. rubens have been used as food for fish fry (Groeneweg & Schluter, 1981; Mookerji & Rao 1994). To improve larval rearing techniques, a good understanding of larval morphology, behaviour, live food and artificial diet requirements, and environmental conditions is fundamental (Liao et al., 2001). Rotifers are cultured by feeding them microalgae. Rotifers can also be fed yeast, but are more nutritious when fed algae, as they have higher protein and lipid contents. Rotifers also have been shown to be more digestible. (Nadolny, 2003). Apart from fresh Baker s yeast, instant baker s yeast, marine yeast or cake yeast may also be used.

2 32 A. Q. K. SULEHRIA ET AL BIOLOGIA (PAKISTAN) The aim of this work was to study the growth rate of mixed culture of rotifers at room temperature, on various combinations of artificial diets such as starch, yeast and albumen. MATERIALS AND METHODS Sample Collection Water sample containing rotifers was collected using Wisconsin Planktonic net of 37 m. Water sample was taken from the bank of Manawa ponds, just below the water surface (about 15-25cm) (Pennak, 1978). Identification of rotifers was carried out by observing their body shape, morphological features and behavior (Hyman, 1951; Ward & Wipple, 1959; Segers, 2007). Culture Media To culture the rotifers on artificial diet media, six combinations of diet media were used, which were as follows: 1. medium 1: 10 ml Distilled H 2 O gm Yeast gm Starch 2. medium 2: O gm Yeast 3. medium 3: 10 ml Distilled H 2 O gm Starch 4. medium 4: 10 ml Distilled H 2 O gm Yeast gm Albumen 5. medium 5: 10 ml Distilled H 2 O gm Yeast gm Starch gm Albumen 6. medium 6: 10 ml Distilled H 2 O gm Albumen 7. Control medium Pond water and natural algae For the preparation of the above-mentioned media seven sets of petriplates were used, each set containing five petri-plates. After the preparation of culture media, one ml mixed rotifer sample was added to each petri-plate. The mixed culture of rotifers contained Brachionus calyciflorus, Brachionus angularis, Filinia Iongiseta, Philodina roseola, and Keratella valga. The counting of rotifers was carried out by haemocytometer and OLYMPUS microscope (Taylor et al., 1997). Rotifer count of each diet media was compared with other diet media and control media by applying t-test to investigate its significant difference at 0.05 probability. RESULTS I (Yeast + Starch) This medium was found to be effective for the growth of rotifers. Number of rotifers increased during first three days and their maximum number was observed on third day, i.e. 50 increase was observed in their number. But there was a decline in number of organisms in last two days.

3 Vol. 56 (1&2) Effect of artificial diets on rotifers 33 Initially ph was 8, but on last day of experiment it was The decrease in biomass was observed in this diet medium. Comparison of rotifers count in diet medium 1 with other diet media by applying t-test showed that, it had significant difference from diet medium 2, 4 and 6, at 0.05 probability and degree of freedom 8 (Table 1, 2). Some species survived till end of the experiment which were Brachionus calyciflorus, Brachionus angularis, Filinia Iongiseta. No. of Days Table 1: Comparison of change in Bimass of six different Media No. of Petriplates A B C D E Mean change (Yeast) In this diet medium there was no increase in rotifer numbers on first day. 5 increase in number was observed on second day. But there was continuous

4 34 A. Q. K. SULEHRIA ET AL BIOLOGIA (PAKISTAN) decline in their number in last three days of experiment. Decrease in biomass was also observed (Fig., 1). Comparison of rotifer count of diet media 2 with other diet media showed its significant difference from diet media 6 at 0.05 probability & degree of freedom 8 (Table 1, 2). In this diet medium maximum number of rotifers died after second day, but among the surviving rotifers Brachionus calyciflorus & Keratella valga were prominent. Table 2: Comparison of t-test values of Rotifer count in six different Media (DM) 3 (Starch) Starch was also found effective diet component for culture of rotifers. In this diet medium continuous increase in number of rotifers was observed up to fourth day of experiment i.e., about 60, increase in number. But number of rotifers decreased on last day (Fig., 1). A decrease in biomass was also determined. t-test showed that this medium has significant difference from diet media 2, 4 and 6, at 0.05 probability & degree of freedom 8 (Table 1, 2). In this diet medium maximum increase was observed in Brachionus angularis and Brachionus calyciflorus. A few Philodina roseola were also present. 4 (Yeast + Albumen) This diet medium did not support the rotifers to maintain their growth. They died rapidly & their number decreased very quickly. Biomass of the petriplates decreased. Comparison of change in biomass of six different diet media showed that in this diet medium minimum mean change was observed i.e., (Table 1). Comparison of rotifer count of this diet medium with other diet media showed insignificant difference, as the number of rotifers decreased rapidly in this diet medium (Table 2). So there were no particular species which grew better and could be identified. 5 (Yeast + Starch + Albumen) This diet medium proved to be very effective for the growth of rotifers, as maximum growth of rotifers was observed in this diet medium. In first three days

5 Vol. 56 (1&2) Effect of artificial diets on rotifers 35 about 70 increase occurred, but number of rotifers decreased in last two days (Fig., 1). Biomass decreased gradually. Comparison of rotifer count of this diet medium with other diet media showed that it had significant difference with diet media 2, 4 and 6 (Table 1, 2). Rotifer species which grew best in this diet medium were Brachionus calyciflorus, Brachionus angularis, Filinia longiseta and Philodina roseola. 6 (Albumen) No growth of rotifers took place in this diet medium. Most rotifers rapidly died in first two days and the rest were died on day 3 to onward. Biomass of this diet medium also decreased. Comparison of this diet medium with other diet media showed insignificant difference (Fig.,1; Table 1-2). DISCUSSION Rotifers are opportunists which respond very quickly to any change in the food types and levels (Nogrady et al., 1993). Rotifers show almost linear numerical addition with rise in food levels and it has been observed in many rotifer genera of family Brachionidae (Dumont et al., 1995; Lucia-Pavon, 2001; Sarma, et al., 2001; Peredo-Alvarez, et al., 2003). The results of present work showed that, the artificial diet can be used to culture the rotifers or to maintain their growth (Hoff & Snell, 1987; Lubzen, 1987). Out of six diet media, the diet medium which contained starch alone, or in combination with other diet components, was effective for the growth of rotifers. However, maximum growth observed in that medium which contained a mixture of yeast, starch and albumen. On the other hand, the diet medium which contained albumen alone or in combination with yeast didn t support the growth of rotifers. Their number declined rapidly in these media. It was due to the fact that, the albumen was not a suitable food component for rotifers or the rotifers did not have the ability to digest the albumen. In the present study, rotifer could not survive more than 4 or 5 days. Because when rotifers were transferred from natural fresh water medium to the artificial diet media, there was a change in their micro-flora i.e., algae and other organic matter present in pond water. The bacteria and other micro-organic particles are important to maintain rotifer culture and to increase their digestibility. (Liao et al., 1993). Other factors may include rise in ph and NH 3. Experiments conducted in present study were very successful, as it provided guide lines for further research in the field of rotifer culture on artificial media. Algae are normally used to culture rotifers throughout the world. Conclusion Finally the present work had proved that: The rotifers can be grown on artificial diet in laboratory, but their life span is short. The results showed that the rotifers are selective in the choice of medium. it means they may grow on a specific type of diet medium, not on all diet media.

6 36 A. Q. K. SULEHRIA ET AL BIOLOGIA (PAKISTAN) Artificial diet media are easily available and easy to maintain. As an alternate food, the artificial diets should be used on large scale for rotifer culture. Large scale availability of rotifers might be beneficial to rear fish fry. Results also indicated that, the presence of specific type of micro-flora are also essential to digest the food for rotifers. REFERENCES Dumont, H. J., Sarma, S. S. S. & Ali, A. J., Laboratory studies on the population dynamics of Anuraeopsis fissa (Rotifera) in relation to food density. Freshwater Biol. 33: Gastesoupe, F.J., Nutritional and antibacterial treatments of live food organisms: the influence on survival, growth rate and weaning success of turbot (Scophthalmus maximus). Ann. Zootech., 31: Groeneweg, J. & Schluter, M., Mass production of freshwater rotifers on liquid wastes II. Mass production of Brachionus rubens Ehrenberg, 1838 in the effluent of high-rate algal ponds used for the treatment of piggery waste. Aquaculture., 25: Habib, M. A. B., Moshihuzzaman, M. & Rahman, M. S., Combined and linear effect of dominant genera of phytoplankton on the abundance of eleven genera of zooplankton. Bangladesh J. Zool., 16: Hoff, F. H. & Snell, T.W., Plankton culture manual, First edition, Florida Aqua Farms, Inc., Florida. USA. 126 pp. Hyman, L. H., The Invertebrates. Vol. III. Acanthocephala, Aschelminthes and Entoprocta. McGraw-Hill, New York. 55 pp. Koven, W.M., Tandler, A., Kissil, G.V., Friezlander, O. & Harel, M., The effect of dietary (n-3) polyunsaturated fatty acids on growth, survival and swim bladder development in Sparus aurata larvae. Aquaculture., 1: Liao, P. H., Vizcarra, A. T., Chen, A. & Lo, K. V., Composting separated solid swine manure. J. Environ. Sci. Health, A28(9): Liao, I.C., Su, H.M. & Chang, E.Y., Techniques in finfish larviculture in Taiwan. Aquaculture. 200:1-31. Lubzens, E., Raising rotifers for use in aquaculture. Hydrobiologia, 147: Lubzens, E., Zmora, O., & Barr, Y., Biotechnology and aquaculture of rotifers. Hydrobiologia, 446: Lucia-Pavon, E., Sarma, S. S. S. & Nandini, S., Effect of different densities of live and dead Chlorella vulgaris on the population growth of rotifers Brachionus calyciflorus and Brachionus patulus (Rotifera). Rev. Biol. Trop. Dic., 49(3-4): Mookerji, N. & Rao, T. R., Influence of ontogenetic changes in prey selection on the survival and growth of rohu, Labeo rohita and singhi, Heteropneustes fossilis larvae. J. Fish Biol., 44: Nadolny,

7 Vol. 56 (1&2) Effect of artificial diets on rotifers 37 Nogrady, T., Wallace, R.L. and Snell, T.W., (eds) Rotifera-guides to the identification of the microinvertebrates of the continental waters of the world. 4 SPB Academic Publishing. The Hague. pp: 142. Pennak, R. W., Fresh-Water Invertebrates of the United States. 2 nd Ed. Wiley, New York. pp:803. Peredo-Alvarez, M. Víctor, Sarma, S. S. S. & Nandini, S., Combined effect of concentrations of algal food (Chlorella vulgaris) and salt (sodium chloride) on the population growth of Brachionus calyciflorus and Brachionus patulus (Rotifera). Rev. Biol. Trop., 51(2): Sarma, S. S. S., Susana, P., Jurado, L. & Nandini, S Effect of three food types on the population growth of Brachionus calyciflorus and Brachionus patulus (Rotifera: Brachionidae). Rev. Biol. Trop., 49(1): Segers, H Annotated checklist of the rotifers (phylum Rotifera), with notes on nomenclature, taxonomy and distribution. Zootaxa. 1564: Taylor, D. J., Green, N. P. O., & Stout, G. W., (Reprinted 2008). Biological Science (Cambridge low price editions). 3 rd Ed. Printed in India at Replika Press Pvt. Ltd., Kundli pp: Watanabe, T., Kitajima, C., & Fujita, S., Nutritional values of live organisms used in Japan for mass propagation of fish: a review. Aquaculture., 34: Ward, H. B. & Whipple, G. C., Fresh Water Biology.2 nd ed. John Wiley and Sons. New York pp.

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