Study On Growth Characteristics Of Litopenaeus Vannamei And Penaeus Monodon During Semi-intensive Earthen Pond-culture

The Litopenaeus vannamei is commonly called white leg shrimp,and distributes originally in southern Amerian ocean. It was introduced into China in 1988. The Penaeus monodon is commonly called straw shrimp or tiger shrimp,and was cultured in C hina mainland since 1980's. With aquiculture development so far, Litopenaeus vannami, Penaeus monodon and Feneropenaeus Chinses are three major high yield shrimp species.This paper studies on growth characteristics of Litopenaeus vannamei and Penaeus monodon during semi-intensive earthen pond-culture in China southern. Research contents involved the growth characteristics of Litopenaeus vannamei during semi-intensive earthen pond-culture, effects of microbial preparation on growth characteristics of Litopenaeus vannamei during semi-intensive earthen pond-culture, the physicochemical factor variation in Litopenaeus vannamei in semi-intensive earth pond, the growth characteristics of Penaeus monodon during semi-intensive earthen pond-culture, effects of microbial preparation on growth characteristics of Penaeus monodon during semi-intensive earthen pond-culture.1.The growth characteristics of Litopenaeus vannamei during semi-intensive earthen pond-cultureOn the purpose of scientific basis for the better manage of Litopenaeus vannamei in semi-intensive earth pond-culture, from May to August in 2009,studies were conducted on the growth characteristics of this shrimp cultured in semi-intensive earth pond. In this way of measure and anlysis to growth parameters(body length and body weight) of samples in two earth-pond(â… andâ…¢) during culture, the results show that: The relation between body length and body weight of Litopenaeus vannamei of semi-intensive earth pond-culture could be significantly described by the power function,separately as following: (â… )W= 0.016L2.8935 (R²=0.989,P<0.01), (â…¢)W=0.0127 L3.0292 (R²=0.9911, P<0.01). In selected earth pond, the body weight growth turning point of Litopenaeus vannamei appeared respectively at the 124th days and 128th days. By using von Bertallanffy growth equation, the growth equations of Litopenaeus vannamei were abtained:â… :Lt=17.6955(1-e-0.0095(t-12.2421)),W_t=65.2846(1-e-0.0095(t-12.2421))2.8935;â…¢:Lt=16.8567(1-e^{-0.0104(t-21.1781)}),W_t=66.0607(1-e^{-0.0104(t-21.1781)})3.0292. 2. Effects of microbial preparation on growth characteristics of Litopenaeus van- namei during semi-intensive earthen pond-cultureOn the way of growth characteristics of Litopenaeus vannamei, the paper studied effects of microbial preparation used in semi-intensive earth pond-culture. From May to September in 2009,30 samples were taken from the four ponds every week, in the way of measure and analysis to growth parameters(body length and body weight). The results show that: (1)The relationship of body-length and body-weight of Litopenaeus vannamei of control and experimental group could be significantly described by the power function,separately as following:W_â… =0.016L2.8935(R²=0.989);W_â…¡=0.0122L^3.0366(R²=0.998 5);W_â…¢=0.0127L^3.0292(R²=0.9911);W_â…£=0.008L^3.2098(R²=0.9974). The body weight growth turning point of Litopenaeus vannamei appeared respectively at the 124th,128th,24th,22th day. By using von Bertallanffy growth equation, the growth equations of Litopenaeus vannamei were abtained:â… :L_t=17.6955(1-e-0.0095(t-12.2421)),W_t=65.2846(1-e-0.0095(t-12.2421) )2.8935;â…¡: L_t=15.1734(1-e^{-0.0167(t-23.2096)}),W_t=46.6974(1-e^{-0.0167(t-23.2096)} )3.0336;â…¢:L_t=16.8567(1-e^{-0.0104(t-21.1781)}),W_t=66.0607(1-e^{-0.0104(t-21.1781)})3.0292;â…£:L_t=15.8919(1-e^{-0.0148(t-21.3041)}),W_t=57.362(1-e^{-0.0148(t-21.3041)})3.2098; (4)After application to microbial preparation,shrimps of experimental group were longer and heavier than ones of control group separately at 56th and 55th. There were significant differences on body-longth and body-weight between experimental group and control group in the same of culture(P<0.01). Shrimp of experimental group were plump,and grew to salable size at transitory time.3.The physicochemical factor variation in Litopenaeus vannamei in semi-intensive earth pondFor improvement of manage of Litopenaeus vannamei in semi-intensive earth pond-culture, studies were conducted the growth of Litopenaeus vannamei and physical-chemical factors in the ponds. The results show that:High NH₄-N harmed shrimp growth,many factors influenced the level of NH₄-N,NO₃-N and NO₂-N. Few factors influenced the level of phosphor, acid sediment absorbed phosphor more strongly. With culture time increasing, organic matter accumulated gradually, pond sediment had important influence on decomposition of organic matter in pond system. Microbiological preparation promoted Litopenaeus vannamei growth, increased water pH and DO,relieve NH4-N variation and optimized water envirement of culture.4. The growth characteristics of Penaeus monodonduring semi-intensive earthen pond-cultureOn the purpose of enlarging culture scale and improving manage of Penaeus monodon in semi-intensive earth pond-culture, from May to August in 2009, studies were conducted on the growth characteristics of this shrimp cultured in semi-intensive earth pond. In this way of measure and anlysis to growth parameters(body length and body weight) of samples in two earth-pond(A and C) during culture,the results show that: The relation between body length and body weight of semi-intensive earth pond-culture Penaeus monodon could be significantly described by the power function,separately as following:(A)W=0.0083 L^3.2753 (R²=0.9988),(C)W=0.0165L^2.9235 (R²=0.9956). In pond A,the body weight growth turning point of Penaeus monodon appeared at the 132th days. By using Von Bertallanffy growth equation,the growth equations of Penaeus monodon were abtained: A:L_t=15.329(1-e^{-0.011(t-24.0776)}),W_t=63.3857(1-e^{-0.011(t-24.0776)})3.3753; (4)The Von Bertallanffy growth equation could fit well to growth regularity of Penaeus monodon when shrimps grew stablly. Effected by bad enviroment, datas of body-longth and body-weight fluctuated violently. According to rules, datas couldn't be dealed and grow equation couldn'd fit growth of Penaeus monodon.5. Effects of microbial preparation on growth characteristics of Penaeus monod- on during semi-intensive earthen pond-cultureOn the way of growth characteristics of Penaeus monodon, the paper studied effects of microbial preparation used in semi-intensive earth pond-culture. From May to September in 2009,30 samples were taken from the four ponds every week, in the way of measure and analysis to growth parameters(body length and body weight).The results show that: The relationsip of body-length and body-weight of Penaeus monodoni of control and experimental group could be significantly described by the power function,separately as following:WA=0.0083L^3.2753(R²=0.9982),WB=0.0098L3.167(R²=0.9993),W_C=0.0165L^2.9235(R²=0.9956),WD=0.0161L^2.9359(R²=0.9988). The body weight growth turning point of Litopenaeus vannamei appeared respectively at the 132th,128th,198th day. By using von Bertallanffy growth equation, the growth equations of Penaeus monodoni were abtained: A:L_t=15.329(1-e^{-0.011(t-24.0776)}),W_t=63.3857(1-e^{-0.011(t-24.0776)})^3.3753; B:L_t=13.9616(1-e^{-0.0104(t-18.9231)}),W_t=38.9398(1-e^{-0.0104(t-18.9231)})^3.167; D:L_t=20.4095(1-e^{-0.0055(t-1.2909)}),W_t=113.4397(1-e^{-0.0055(t-1.2909)})^2.9398; (4)After application to microbial preparation, shrimps of experimental group survived longer in bad enviroment. Microbial preparation could help Penaeus monodoni to resist bad influence of cyanobacteria bloom.