LARVAL CULTURE OF PENAEID SHRIMP AT THE GALVESTON 



BIOLOGICAL LABORATORY' 



CORNELIUS R. MOCK' 



PRELIMINARY EXPERIMENTATION 



The first larval culture experiments at the Na- 

 tional Marine Fisheries Service Galveston Labora- 

 tory were conducted to aid the identification and 

 description of the larval stages of penaeids found in 

 the Gulf of Mexico. By 1966 the three commercially 

 important penaeid shrimp (white shrimp. Peiiaciis 

 setiferus; brown shrimp, P. aztecus; and pink 

 shrimp, P. dtiorariim) had been reared to the post- 

 larval stage. The basic techniques used to culture 

 larval shrimp were similar to those described by 

 Hudinaga (1942) and Hudinaga and Miyamura 

 (1962). 



During this period the following organisms were 

 tested individually as foods for the larval shrimp: 

 Skclctoiieina costatiim, Eiicampi sp., Gym- 

 nodinhim splendcns. Tetraselmis sp., Tliiilassiosira 

 sp., a euglenoid protozoan, and Artemia sp. As a 

 result of this work, two suitable food organisms were 

 selected for use in subsequent experiments. These 

 were Skelctonemu costatiim, because it could be 

 cultured easily, and Artemia sp., because it was 

 readily available (Cook and Murphy, 1966; Cook, 

 1967). 



Following the initial phase of this work, research 

 was directed toward developing methods of rearing 

 penaeid larvae en masse in order to supply shrimp 

 grown under known conditions for physiological 

 studies and forexperimental pond culture. A variety 

 of specialized equipment was designed and tested in 

 an attempt to perfect larval culture techniques. 



PROGRESS BETWEEN 1966-1969 



From 1966 to 1969, considerable effort was di- 



rected toward growing mass cultures of algal foods in 

 natural seawater. Although samples of seawater 

 were tested prior to each experiment with several 

 types of fertilizers to determine which combinations 

 of nutrients should be used with that batch of seawa- 

 ter for best algal growth, satisfactory growth did not 

 always occur. It soon became apparent that a more 

 reliable medium than seawater was needed. A 

 number of media made with synthetic sea salts and 

 tap water were tested. "'Instant Ocean"^ was cho- 

 sen from those tested for use at the Galveston 

 Laboratory along with a complement of nutrients, 

 trace elements, and vitamins (Mock and Murphy, 

 1971). With this medium dense unialgal cultures can 

 be grown and maintained. For example, 300 liters of 

 Skeletonema costatiim can be cultured from an 

 8-liter starter culture to a density of 4-5 x 10" cells 

 per milliliter in 4 days. 



Additional algal foods fed experimentally in- 

 cluded Cyclotella nana. Isochiysis galbana, and 

 Cerataiilina sp. 



Based on observations made during this ex- 

 perimentation the following conclusions were made: 

 1 ) the responses of Penaeiis aztecus larvae to differ- 

 ent light intensities were inconsistent; 2) a tempera- 

 ture range of 28°-30°C (82°-86°F) and a salinity range 

 of 27-35"/i]o were most satisfactory for penaeid larval 

 culture; 3) addition of several algal foods gave better 

 survival than additions of only a single species when 

 comparable concentrations were used; 4) the omis- 

 sion of antibiotics from the larval culture media was 

 possible when the chelator EDTA (ethylene- 

 diaminetetraacetic acid) was substituted at 

 concentrations of 0.01 g per liter of seawater; and 5) 

 postlarvae could be shipped successfully either by 

 motor vehicle or air when placed in plastic bags filled 

 with oxygen and seawater (Cook, 1965, 1966, 1968, 

 1969). 



' Contribution No. .144 from the National Marine Fisheries 

 ,Ser\ice. Galveston Laboratory. Galveston. Texas. 



- Gulf Coastal Fisheries Center. National Marine Fisheries 

 Service. NOAA. Fon Crockett. Galveston. TX 77550. 



' Reference to trade names does not imply endorsement hy the 

 National Marine Fisheries Service. NOAA. 



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