J. of Aquaculture Vol. 19(3) : 178-182, 2006 µ Journal of Aquaculture Korean Aquaculture Society 해산어류자어의초기먹이생물인로티퍼의최초섭이일령과포식수분석을위한새로운관찰및계수방법 *, y 1, 2, Ÿ 3 w, 1 2 w q l 3 w ûw q l Studies about New Observation and Counting Method for Analysis of First Feeding Day and Daily Feeding Numbers of Rotifer by Marine Fish Larvae Min-min Jung*, Chong-hwan Wi 1, Young-ju Ji 2 and Kwang-sik Min 3 *National Fisheries Research and Development Institute (NFRDI), Jeju Fisheries Research Institute, Jeju-do 690-192, Korea 1 Gyeongsangbukdo Fishery Resources Development Institute, Gyeongsangbuk-do 766-850, Korea 2 National Fisheries Research and Development Institute (NFRDI), Jeju Fisheries Research Institute, Shellfish genetics and Breeding Research Center, Jeju-do 695-835, Korea 3 National Fisheries Research and Development Institute (NFRDI), South Sea Fisheries Research Institute, Shellfish Research Center, Gyeongsangnam-do 668-820, Korea We studied new observation method about take process of rotifer by marine fish larvae. Till now, we can not accurate observation and count of first rotifer feeding day and/or feeding numbers of rotifer by marine fish larvae. Because take rotifer is ingested and disappeared in the digestive system of fish larvae. However we suggest possible observation method for these problems. The trophi is mastication organ of rotifer, and has only one in each rotifer individual. The trophi is left in the mastication organ because sole indigestible organ of rotifer. Therefore we can accurate observation and count of first rotifer feeding day and/or feeding rotifer numbers of marine fish larvae by trophi observation method (RTCM; Rotifer Trophi Counting Method). Keywords: First feeding, Live food organism, Marine fish larvae, Rotifer, RTCM, Rotifer trophi counting method, Trophi ú e w šƒƒe», e y», e š œ» y x ƒw». z» wg œ ƒw w» w y» ƒ pr(rotifer)ƒ ƒw» (Fujita, 1973). w» prƒ ú ƒw. ¾ w pr *Corresponding author: jungminmin@hanmail.net 178 pr (Hirayama, 1985; Yamasaki et al., 1987),» (Kitajima, 1983), pr y (Watanabe et al., 1979) š pr kw (Jung et al., 1997) w, 20,000 /ml š ƒw (Yoshimura et al., 1996). ù x w pr ƒw, ƒ ƒ pr? ù? š l ¾ pr w? w ƒ. ÿ w pr yw yw». w ƒ š e» w pr w
pr s yw w wš w. pr»(trophi) y e w w Brachionus pr x ü w ü» w. pr 50 ml f(z 40 ml) wš» Ÿwx (Olympus, SZH) w. 25 o C z, 30 ppt š Ÿ» 12L:12D w 16 e w. pr 2 w. pr 20 ind./40 ml š 2 x q w 3z w z ƒ 7 10 5 cells/mlƒ qš Nannochloropsis oculata ƒw. pr» xk w x š pr SS (super small) type pr p t š k pr p(brachionus rotundiformis, Thai rotifer strain) m» xk w. y»ü» pr ƒwš ƒ w z y» ü» yw. y»ü»ƒ yz w ¾ x k w» w w w» yw. z pr ƒw z 7~10 w. e» y»ü» w t e» prƒ ƒš» w pr w pr ƒw m w. e z pr ƒw z 24 w. pr» y x 20 ind./40 ml w pr 16 pr» (RTCM) 179 Fig. 1. Culture of rotifer for the trophi observation. Fig. 2. Remained cell numbers of N. oculata in the rotifer culture tank.» š w š ùkü, 16¾ ƒw 3,674 ind./ 40 ml ƒw(fig. 1). wr ƒw N. oculata z 2 š wù z 6l N. oculata zero (0) k(fig. 2). pr ü» y w xü pr Ÿwx w» w, x (n=100 ) pr 1 1» ƒš (Fig. 3). pr» xk k pr p(b. rotundiformis, Thai rotifer strain) l w» xk x Brahionus xk p ƒš.» incus x w yw xk w»ƒ ù malleus w xk w. p malleus
180, y,, Ÿ Fig. 3. Confirmed trophi (oval circles) existence in the each rotifer bodies. A; existed trophi in the rotifer body ( 100 magnification), B; location of rotifer trophi ( 400 magnification). Fig. 4. The malleus of rotifer, B. rotundiformis trophi. A; uncus, B; manubrium in malleus ( 1,000 magnification). w manubrium uncus xkƒ k. w x» š k pr p uncus (Fig. 4-A) w manubrium (Fig. 4-B) y. y»ü» w() ƒ pr w z yü w» ywš w yw. wš w š ƒw w w. w evvr vr w w wš wš w û¼. š f. f ƒ w w ü. f ƒ k(fig. 5-A). Ÿwx ƒw Fig. 5 B Ÿw x w w y» yw w Fig. 5 C y»ü w pr» Fig. 5. Development of trophi observation method in the gut of marine fish larvae. A; compression of marine fish larvae. B; observation of gut ( 40 magnification). C; counting of trophi in the gut ( 100 magnification). Fig. 6. Confirmed rotifer trophi (oval circle) in the excretion of marine fish larvae ( 100 magnification). w., pr m y ƒ ù» w ƒ ƒw., w w yw» x w (Fig. 6). e» y»ü» pr w e» y»ü»» w w z 24 e pr
Fig. 7. Confirmed rotifer trophi in the gut of early flat fish larvae. A; opened mouse flat fish larvae ( 40 magnification). B; gut of flat fish larvae ( 100 magnification). C; confirmed rotifer trophi in the gut ( 400 magnification). D; rotifer trophi ( 1,000 magnification). w y»ü»ƒ y. w w pr» mw yw (Fig. 7). š w œ w» pr l vjm w. pr ƒ yw z w úl 15, l y z w ú» 15 zw pr wì wƒ pr š l wš. š w l w 20 l w» w (Eda et al., 1990; Han et al., 1998). w» ƒ w pr œ w w» v ƒ¾ ü sw. ƒ ú z»» pr wš. š y 5 ü» 1 ml» 5 ü ƒwƒ ƒw pr ƒjš. w wš w ü» ƒw pr ƒ š ù yw w ¾. y»ü w pr m w pr» (RTCM) 181 š. ù y»ü pr yw. pr 2,500 w w x š Brachionus pr» w e w (Ito, 1958a; 1958b; 1960). pr 2~20 µm j» ù z š ³ xk y w z w»š w» w y» ü(fulks and Main, 1991). pr y w w w» pr ü 1 xk wš pr»» w (Wallace and Snell, 1991). w» ƒ pr w? š pr w w» w. ÿw w pr kùl ü 1» ƒš w y»ü w» w w pr w w pr yw y w». w pr y» mw m y w y» wì yw. w w x mw w pr w pr ƒ w. mw y»ü w pr w» yw pr» (RTCM; Rotifer Trophi Counting Method) w w pr pr yw w w. w» ƒ w pr w. ¾ w w l pr ƒw? š w p r w? yw w. ÿw ƒ w pr(m) y»ü y ƒ w». ù w w w pr»
182, y,, Ÿ (trophi) w w. pr ƒ w» ƒ» w y»ü y š xk w. w y»ü» w w (RTCM; Rotifer Trophi Counting Method) w pr w w s pr yw w. w( l,, RP-2006-AQ-013) w. šx Eda, H., R, Murashige, Y. Oozeki and A. Hagiwara, 1990. Factors affecting intensive larval rearing of striped mullet, Mugil cephalus. Aquaculture, 91, 281 294. Fujita, S., 1973. Importance of zooplankton mass culture in producing marine fish seed for fish farming. Bull. Plank. Soc. Japan, 20, 49 53. Fulks, W. and K. L. Main, 1991. Rotifer and microalgae culture systems. Proceedings of a U. S.-Asia workshop. Honolulu, Hawaii, 355 pp. Han, H.-K., H.-W., Kang and K.-H., Ryee, 1998. A study on early growth in seedling production of the greenling, Hexagrammos otakii. Bull. Nat. Fish. Res. Dev. Inst., 54, 69 77. Hirayama, K., 1985. Biological aspects of the rotifer Brachionus plicatilis as a food organism for mass culture of seedling. Coll. Fr.-Japon. Oceanogr., 8, 41 50. Ito, T., 1958a. Studies on the Mizukawari in eel-culture ponds. X. The density of dormant eggs of rotifer on bottom deposite in eel-culture ponds. Report Fac. Fish. Pref. Univ. Mie., 3, 170 177. Ito, T., 1958b. Studies on the "Mizukawari" in eel-culture ponds. XI. The hatching activity of dormant eggs of Brachionus plicatilis O. F. Muller. Report Fac. Fish. Pref. Univ. Mie., 3, 178 192. Ito, T., 1960. On the culture of mixohaline rotifer Brachionus plicatilis O. F. Muller in the seawater. Rep. Fac. Fish. Mie Pref. Univ., 3, 708 740. Jung, M.-M., A. Hagiwara and K. Hirayama, 1997. Interspecific interactions in the rotifer microcosm. Hydrobiologia, 358, 121 126. Kitajima, C., 1983. Mass culture-actual examples. (in) Japan Soc. Sci. Fish. (ed.), The Rotifer Brachionus plicatilis Biology and Mass Culture. Koseisha Koseikaku, Tokyo, pp. 102 128. Wallace, R. L. and T. W. Snell, 1991. Rotifera. Ecology and Classification of North American Freshwater Invertebrates. Academic Press, Inc. pp. 187 248. Watanabe, T., F. Oowa, C. Kitajima, S. Fujita and Y. Yone, 1979. Relationship between the dietary value of rotifers Brachionus plicatilis and their content of 3 highly unsaturated fatty acids. Bull. Japanese Soc. Sci. Fish., 45, 883 889. Yamasaki, S., D. H. Secor and H. Hirata, 1987. Population growth of two types of rotifer (L and S) Brachionus plicatilis at different dissolved oxygen levels. Nippon Suisan Gakkaishi, 53, 1303. Yoshimura, K., A. Hagiwara, T. Yoshimatsu and C. Kitajima, 1996. Culture technology of marine rotifers and the implications for intensive culture of marine fish in Japan. Mar. Freshwater Res., 47, 217 222. š : 2006 5 24 : 2006 8 11