Progress 06/01/02 to 05/31/08
Outputs
Red snapper brooders were fed a control or enriched diet. The control diet group gave 63 spawns while the enriched diet group gave 22 spawns. Mean egg production was 4.2 and 0.4 million eggs for the control and the enriched diet groups respectively. The mean fertilization rate, the hatch rate and the survival at 36-40 hph were 90.5%, 83% and 49% respectively for the control treatment. The above parameters for the one fertilized spawn of the enriched diet group were 99%, 87% and 70. Administration of free amino acids (FAA) as part of the hormone-induced spawning process increased concentrations in the eggs and larvae. Fish given a free amino acid (FAA) cocktail containing 250 mM valine, lysine, leucine, and isoleucine respectively at a rate of 20mg FAA/kg of fish body weight. showed a significant increase of lysine in the plasma. Newly spawned eggs from control females had a mean total FAA content of 22.1 nanomoles/egg, while eggs from FAA-injected females had a mean
total FAA content of 28.3 nanomoles/egg. Valine, lysine, leucine, and isoleucine FAA content in eggs from treated fish increased by 27.0%, 28.7%, 28.3%, and 28.7% respectively compared to the control eggs Acclimation and enrichment of copepod nauplii with FAA was evaluated using a combination of four FAA (lysine, leucine, isoleucine and valine). Nauplii sampled immediately after trapping from the ponds (control) contained 28.25 pmol of total FAA/individual. Enrichment in FAA resulted in 40.41 pmol total FAA/individual, Movement and survival of age-0 red snapper (n=2000) on 32 artificial reefs in the northern Gulf of Mexico was studies. All fish were tagged with a visible of red, orange, green, or yellow implant fluorescent elastomer (VIE) tag under the external edge of the eye membrane and marked with either Alizarin red S or Oxytetracycline dihydrate (OTC) dye. One week after stocking, survival was 27% for green fish, 47% for yellow, 57% for red, and 100% for orange. A month later,
survival was 17% for green, 18% for yellow, 30% for red, and 32% for orange tagged fish. Tag retention by fish in a laboratory setting 48 days after tagging was 85% for orange fish, 67% for green, 91% for yellow, 82% for red, and 67% for control fish. The growth and survival of first-feeding larval red snapper was evaluated offering the ciliated protozoan Fabrea salinas. The addition of Fabrea along with copepod nauplii improved snapper survival relative to using only nauplii or only Fabrea. Survival of red snapper larvae in saltwater (32 ppt) primary nursery ponds prepared using varying organic fertilizer concentrations and different time intervals prior to stocking was studies. Survival was highly variable with the best pond having a survival of 1%. Attempts to control cannibalism among recently metamorphosed snapper using water velocity was evaluated. The tanks had a water flow of 3.5, 7 or 14 L/minute with four replicates per flow rate. There was a trend towards greater survival
the greater the flow rate. Survival was strongly correlated to mean initial and final length (R2=0.74, P=0.0001; and R2=0.84, P=0.0003) and to a lesser degree the CV of length at harvest (R2=0.66, P=0.008).
Impacts
Red snapper is one of the most important fish in the commercial and sport fisheries of the Gulf of Mexico. Improved management of the fisheries can be gained by an improved understanding of red snapper life history. Techniques have been developed to provide fingerlings for tagging programs, and aquaculture have been developed. Controlled spawning can be achieved in a hatchery setting. Advances in understanding factors affecting egg and larval quality will lead to improved availability of fish. Larval quality can be improved by providing additional free amino acids needed for development by injection of brooders prior to ovulation or by enrichment of the food quality given the larvae. Alternative live foods such as Fabrea salina improve larval survival. Such techniques have application not only for red snapper but many other marine species. Hatchery produced red snapper can be tagged and released in the wild and their use of artificial reefs, and their growth and
survival be determined
Publications
- Papanikos, N., R.P. Phelps, K. Williams, A. Ferry and D. Maus. 2003. Egg and larval quality of natural and induced spawns of red snapper, Lutjanus campechnaus. Fish Physiology and Biochemistry 28:487-488.
- Williams, K; Papanikos, N; Phelps, RP; Shardo, JD. 2004. Development, growth, and yolk utilization of hatchery-reared red snapper Lutjanus campechanus larvae. Marine Ecology Progress Series. 275, 231-239.
- Ross, Michael. 2003. Lipid and fatty acid composition of red snapper, Lutjanus campechnaus, ovaries and eggs. MS thesis, Auburn University.
- Sumiarsa, Gede Suwarthama. 2003. Production and fatty acid profiles of cyclopoid copepod nauplii Apocyclops panamensis. Doctoral dissertation, Auburn University.
- Papanikos, Nikolas. 2004. Egg quality of red snapper Lutjanus campechanus, significance of spawning method and broodfish nutrition. Doctoral dissertation, Auburn University.
- Hastey, Ryan P. 2005. Supplementing free amino acids to maternal red snapper, Lutjanus campechanus, brood stoock and measuring the effects on eggs and larvae. MS thesis, Auburn University.
- Lindley, Laban C. 2005. Collection and free amino acid enhancement of copepod nauplii for first-feeding larval red snapper, Lutjanus campechanus. MS thesis, Auburn University.
- Rhodes, Melanie A. 2005. Evaluation of Fabrea salina and other ciliates as alternative first foods for first-feeding red snapper, Lutjanus campechanus, larvae. MS thesis, Auburn University.
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Progress 01/01/04 to 12/31/04
Outputs
The growth and survival of first-feeding larval red snapper, Lutjanus campechanus, was evaluated offering the ciliated protozoan Fabrea salinas as a first food in a production setting using 1m3 tanks. Red snapper larvae were stocked at 10 L-1, 36 hrs post hatch, prior to functioning mouthparts. Three treatments: 1) mixed zooplankton 20-75microm (primarily copepod nauplii and rotifers) only from days 1 to 10; 2) copepod nauplii from days 1 to 10 plus ciliates from days 1 to 5; and 3) ciliates only from days 1 to 3 plus copepod nauplii from days 4 to 10. Survival after 28 days was 0.28% and 2.39% in treatment 1 and 2, respectively. Treatment 3 did not have any survival after day 4 of functional mouthparts. At harvest, the average lengths of larvae were 11.45 mm and 13.45 mm respectively for tanks given only copepods or those given Fabrea and copepods. Larvae were more active feeders in the tanks given Fabrea and copepods as a first food. The average daily reduction in
copepod nauplii density was 45.4% in such tanks, while averaging 15.7 % when only nauplii were given as a first food. Survival was positively related to the percent daily reduction in nauplii abundance (R2= 0.81, P= 0.002). A study was conducted to examine the survival of red snapper larvae in saltwater (32 ppt) primary nursery ponds when prepared using varying organic fertilizer concentrations and different time interval prior to stocking. Brooders were caught from the wild and induced to spawn using HCG. Larvae were stocked into marine ponds at different time schedules (5, 7, and 10 d) following initial pond filling at a density of 250,000/ha. After 30 d all ponds were harvested and survival determined. Survival was highly variable with the best pond having a survival of 1%. No survival was found in ponds fertilized with 250 kg/ha rice bran and prepared either 5 or 7 days prior to stocking or in ponds fertilized with 500 kg/ha rice bran and prepared 10 days prior to stocking.
Cannibalism is an issue with recently metamorphosed snapper (30-40 d post-hatch ). One method to control cannibalism is to create a current of water forcing the fish to maintain itself oriented into the current reducing the opportunity for cannibalism. Thirty five day old snapper were stocked into 1 m3 tanks at 100/m3 and cultured for 18 d. The tanks had a water flow of 3.5, 7 or 14 L/minute with four replicates per flow rate. There was a trend towards greater survival the greater the flow rate, but not statistically so due to variation among replicates. Survival was strongly correlated to mean initial and final length (R2=0.74, P=0.0001; and R2=0.84, P=0.0003) and to a lesser degree the CV of length at harvest (R2=0.66, P=0.008). The smaller the fish the lower the survival rate.
Impacts
Ciliated protozoans such as Fabrea salina may help provide the missing link for the first feeding of red snapper larvae. Previous work with copepod nauplii as a first food showed that other food items might be important in the first day of exogenous feeding. Fabrea has proven to be reliable to culture and its use can improve snapper survival. Use of primary nursery ponds for red snapper larvae will require addition study before their appropriateness for larval culture can be determined. Survival rates obtained in open ponds were similar to that obtained in some of the initial trials of intensive larval production. Zooplankton production in ponds proved to be highly variable and may be a major factor affecting snapper survival. Careful grading of snapper juveniles during the period from 30 to 60 day and the use of a flow rate of 14L/min can help improve snapper survival.
Publications
- Williams, K; Papanikos, N; Phelps, RP; Shardo, JD, 2004. Development, growth, and yolk utilization of hatchery-reared red snapper Lutjanus campechanus larvae. Marine Ecology Progress Series 275: 231-239.
- Papanikos, N; Phelps, R P; Williams, K; Ferry, A; Maus, D, 2003. Egg and larval quality of natural and induced spawns of red snapper, Lutjanus campechanus. Fish Physiology and Biochemistry 28: 487-488.
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Progress 01/01/03 to 12/31/03
Outputs
Administration of free amino acids (FAA) as part of the hormone-induced spawning process increased concentrations in the eggs and larvae. Half the fish were injected with only HCG. The other half of the fish were injected with HCG and also immediately injected with a free amino acid (FAA) cocktail containing 250 mM valine, lysine, leucine, and isoleucine respectively at a rate of 20mg FAA/kg of fish body weight. Plasma samples showed a significant increase of lysine from the FAA-injected snapper compared to the controls at 30 hours post-injection. Newly spawned eggs from control females had a mean total FAA content of 22.1 nanomoles/egg, while eggs from FAA-injected females had a mean total FAA content of 28.3 nanomoles/egg. Valine, lysine, leucine, and isoleucine FAA content in eggs from treated fish increased by 27.0%, 28.7%, 28.3%, and 28.7% respectively compared to the control eggs. At 24 hrs post-hatch the mean total FAA content of the hatched larvae had
decreased by 79.6% and 84.8% since fertilization for the control and FAA-injected fish. No significant differences between treatments were found for % fertilization, % hatch, or for % survival of larvae right before first feeding. Acclimation and enrichment of copepod nauplii with FAA was evaluated. Several different enrichment protocol treatments were compared using a combination of four FAA (lysine, leucine, isoleucine and valine) at various concentrations. Fatty acid (FA) enrichment (Super Selco) was also added to two treatments in addition to FAA to measure the effect of FA on the absorption of FAA. Acclimated and enriched nauplii increased their level of FAA above that of the control. Nauplii sampled immediately after trapping from the ponds (control) contained 28.25 pmol of total FAA/individual. This level declined by 11% over the 3 h experimental period.. The acclimation/enrichment of nauplii with FAA/FA at the highest concentration tested resulted in 40.41 pmol total
FAA/individual, a 43% increase over control nauplii. The acclimation/enrichment with FAA at the lowest concentration and without any FA enrichment showed an 84% increase in total FAA. Movement and survival of age-0 red snapper (n=2000) on 32 artificial reefs in the northern Gulf of Mexico was studies. All fish were tagged with a visible implant fluorescent elastomer (VIE) tag under the external edge of the eye membrane. There were four groups of fish each marked with a single color of red, orange, green, or yellow. All fish were also marked with either Alizarin red S or Oxytetracycline dihydrate (OTC) dye. One week after stocking, survival was 27% for green fish, 47% for yellow, 57% for red, and 100% for orange. A month later, survival was 17% for green, 18% for yellow, 30% for red, and 32% for orange tagged fish. Marked fish were present on 91% of all 32 experimental reefs. Tagged and non-tagged fish were held in a closed seawater system to compare mortality rates, VIE tag and
fluorescent mark retention. Tag retention 48 days after tagging was 85% for orange fish, 67% for green, 91% for yellow, 82% for red, and 67% for control fish.
Impacts
Larval quality can be improved by providing additional free amino acids needed for development by injection of brooders prior to ovulation or by enrichment of the food quality given the larvae. Such techniques have application not only for red snapper but many other marine species. Hatchery produced red snapper can be tagged and released in the wild and their use of artificial reefs, and their growth and survival be determined.
Publications
- No publications reported this period
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Progress 01/01/02 to 12/31/02
Outputs
Red snapper brooders were fed a control diet consisted of the raw ingredients that were ground and mixed with hot water and gelatin as a binder. The enriched diet was similar to control plus menhaden oil and a vitamin and mineral premix.. The control diet group had better reproductive performance. The control diet group gave 63 spawns while the enriched diet group gave 22 spawns. Mean egg production was 4.2 and 0.4 million eggs for the control and the enriched diet groups respectively. Fertilized spawns, larger than 50,000 eggs, were received from both treatments, 22 from the control and just one from the enriched treatment. The mean fertilization rate, the hatch rate and the survival at 36-40 hph were 90.5%, 83% and 49% respectively for the control treatment. The above parameters for the one fertilized spawn of the enriched diet group were 99%, 87% and 70. Eggs from natural and induced spawns were compared. Natural spawns were found to have significantly higher
fertilization rate, hatch rate, and survival at 36 hours post hatch. Also, eggs from natural spawns were significantly larger and had significantly larger oil globules relative to eggs from induced spawns. Natural spawns had significantly less eggs per ml (2,135, n=19) relative to induced spawns (2,217 , n=14). Measurements of diameter of eggs and oil globules showed that red snapper eggs do not change significantly in size throughout time, during the first few hours after fertilization. Snapper eggs incubated at 24, 26 and 28 C differed in time to hatch, size of larvae produced and larval survival. Optimum temperature for incubation and larval rearing was 26 C. Red snapper juveniles were produced, marked and released on to artifical reefs.
Impacts
The combination of first feeds and larval rearing conditions is essential to establishing protocols that will lead to the reliable, repeatable production of red snapper
Publications
- No publications reported this period
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