Reproductive response of the penaeid shrimp Penaeus aztecus Ives, Penaeus setiferus (L), Penaeus stylirostris Stimpson, and Penaeus vannamei Boone to temperature with reference to ecological aspects of the northwestern Gulf of Mexico shrimp fishery /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1991.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | Conditions known to produce ovarian maturation and spawning in Penaeus stylirostris were reversed to reduce spawning. Reproductive response of P. stylirostris decreased with reduced temperature. Results indicate that low temperature and high salinity should be further investigated as a means to extend penaeid shrimp reproduction for selective breeding studies. Penaeus setiferus and P. vannamei were induced to mature and spawn out of phase with their normal cycle. Cyclically lowering and raising ambient temperature induced P. setiferus and P. vannamei to increase the number of eggs produced. Higher median salinities of 30.0 and 32.0 ppt and lower temperatures of 27.0°C and 27.0°C for P. setiferus and P. vannamei, respectively, were more effective than lower salinities of 26.0 and 25.0 ppt and higher temperatures of 29.0 and 29.0°C, respectively, for increasing reproductive output. Also, cyclically increasing and decreasing ambient temperature appeared to enhance spermatophore transfer by males. Penaeus aztecus was matured and spawned, producing viable eggs under laboratory conditions. Evidence of spermatophore transfer under laboratory conditions included the presence both of sperm and a soft carapace, plus lack of ovarian development. Multiple regression analysis showed that without substrates, other environmental factors have a direct effect and that the presence of substrates has an indirect effect on maturation and spermatophore transfer. Another observation was that P. aztecus can be mated, and will mature at 20°C. A hypothesis is proposed for the maturation and spawning of P. aztecus in relation to the temperature of the mixed layer and thermocline in the Gulf of Mexico. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Wildlife and Fisheries Sciences." |
| Physical Description: | x, 133 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |