Influence of Population Density upon Reproduction on Killie-fish

Abstract

I Studyed on the influence of the population density of Killie-fish (Orysias talipes T &S) upon the number of spawn eggs, hatching-rate, and consequentry upon the reproduction. In the present study these fishes were cultured a paii (I 9 and 1) 1, 2 and 4 pairs respectively in 3 glass bowls (diameter 30cm, depth 15 cm) filled with 7 L. of water, and were given food daily into each groups at the ratio of 1,2,. 4, and the rearing water of each bowl were changed 2~3 times in a week at the same ratio as above. Their spawned eggs were counts 3-~4 times every day, and transfered into each 3 glass bottles (capacity 200cc) which filled water at the above ratio also, and disinfected by 0.5% of formalin solution every 4~5 days, and the fry which hatch out were counted every day. These e^perime its were carryed on two times in the same way. © 1949, The Japanese Society of Fisheries Science. All rights reserved.