STUDIES ON THE GROWTH AND REPRODUCTION OF TUBIFEX TUBIFEX MLLER

The growth and reproduction of Tubifex tubifex have been studied in laboratory cultures at different water temperatures(15℃,20℃,25℃). The life cycle of T. tubifex, takes 100 to 123 days in experimental culture at 15℃,70 to 90 days at 20℃ and 48 to 64 days at 25℃. During the experimental period(165 days as maximum observed), the regression formula describing the growth of weight of animals at 15℃ is :W=6 87/1+136.48·exp(-0.0612t),at 20℃: W=5.99/1+118.8·exp(-0.0918t) and at 25℃: W=6 82/1+135.28·exp(-0.1389t). The regression formula describing the growth of length of animals at 15℃ is: L=58.3/1+13.58·exp(-0.0384t), at 20℃: L=51.3/1+ 11.83·exp(-0.0566t) and at 25℃: L=54.4/1+12.6·exp(-0.0872t). The regression formula describing the relationship between weight and length of animals at 15℃ is: W= 3.1072L1.9486, at 20℃: W=2.9228L1.9781 and at 25℃: W=2.6725L1.9875. In addition, the relationship between growth of animals and water temperature was discussed.