[Comparative studies on individual growth and development of three Brachionus angularis strains].

The embryonic developmental period (De), pre-reproductive period (Dp), the least generation time (Tg), body size of juveniles and adults, egg volume and relative egg volume of three strain Brachionus angularis from Qingdao, Guangzhou and Wuhu were studied with Scenedesmus obliquus at 2.4 x 10(6) cells.ml-1 as the rotifers' food at 25 degrees C. We found that there were significantly different in De, Dp and Tg of three strains. De of WH strain was the top, and subsequently was GZ strain and QD strain. QD strain had the longest Dp, but GZ strain had the shortest. Tg in GZ strain was the shortest, and QD strain, and WH strain were longer, respectively, but no significantly difference existed in the later two. De tended to decrease as the relative egg volume increased in the three strains. Body size at the same stage in pre-reproductive period of three strains was significantly different. WH strain had the largest body size during all of the stages. The relationships between body size and the age of the juvenile of QD, GZ and WH strain were all curvilinear. The variance of the neonates and the adults was 244.24% in WH strain, and 182.89%, 156.28% in QD and GZ strain, respectively. The adults' body size, egg size, and relative egg size was significantly different in three strains.