• Journal of Aquaculture
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• v.15 no.1
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• pp.23-29
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• 2002

To develop techniques for the production of artificial seedling of Corbicula japonica, protocols for induction of spawning and larval development were developed. During the assumed spawning period of August to mid-September, attempts were first made to induce spawning by gonadal incision and UV-irradiation but all in vain. At the end of August, elevated thermal induction evoked 90 % positive response in animals maintained at $3\textperthousand$ salinity. Immersion in (1/1000~3/1000 N) ammonium hydroxide ($NH_4$OH) also induced spawning in 15~45%) of the treated animals at $3\textperthousand$ salinity. Fertilized eggs measured 86$\mum. At 23.0~24.5$^{\circ}C$, the fertilized egos developed into 4-cell stage embryos within 2 hours, trochophores 15 hours, D-shaped larvae 2 days, umbo 9 days and fully grown veligers, ready to infiltrate into the sediment, within 16 days.

• Journal of Aquaculture
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• v.9 no.2
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• pp.109-115
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• 1996

Tagging method, recapture frequencies and mortalities were investigated to obtain the basic data for the effective release technique of abalone, Haliotis discus hannai. Tagged and untagged H. discus hannai were reared for 90 days in the laboratory. Attachment of plastic piece by Alteco was used as tag material. The growth, mortality and falling rate of tags were examined. Data from stock in natural condition showed that fishing rate, fishing mortality and natural mortality of tagged group were 0.04, 0.0195 and 0.4652, respectively.

• Journal of Aquaculture
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• v.9 no.1
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• pp.11-18
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• 1996

We described morphological characteristics of embryonic, larval, and juvenile period of the yellow puffer, Takifugu obscurus. We defined seven periods of embryogenesis the zygote, cleavage, blastula, gastrula, segmentation, pharygula, and hatching periods. The eggs were adhesive and spherical in shape. The egg yolk had numerous tiny oil globules. Hatching began about 280 hours after insemination at $17.0{\pm}1.0^{\circ}C$ water temperature. Melanopores of star shape were seen on yolk, head and trunk during the pharygula and hatching period. The hatched larvae haying large yolk were $3.00\~3.54$ mm in size with $25\~26$ myomeres. The larvae completely absorbed the yolk materials and oil globules within 7 days after hatching and became post-larvae. Laval fish became juveniles within 60 days after hatching, and they reached $23.54\~30.12$ mm in total length and had fin-rays.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.161-168
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• 2016

In this study, growth enhancing effect of hatchery waste egg decomposed liquid fertilizer in pepper plant cultivation through chlorophyll fluorescence (O-J-I-P) analysis. In a whole growth period, egg decomposed fertilizer treated pepper grew well than non treated plant, though it was not statistically significantly different. Amount of chlorophyll fluorescence of non treated plant was higher thant that of fertilizer treated plant. It is determined that eventually lead to increased photosynthesis. In this study, six parameters, Fo, ABS/RC, RC/ABS, TRo/RC, DI0/RC, and DF Total ABS were the important factors represent efficiency of photochemical responses of pepper plant treated with hatchery waste egg decomposed fertilizer.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.82-87
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• 2008

Marine fisheries are important natural resources and must be maintained, especially fish species that are important sources of food. Despite the increase in stocking programs to maintain fisheries with artificially raised fish, the genetic impact stocking has on the wild fry population has not been addressed. Genetic variation in rock bream, Oplegnathus fasciatus, within and between wild-caught parents and the $F_1$ generation produced by them in 1 day was assayed using nine highly variable micro satellite markers. The nine micro satellite loci used in this study displayed diverse polymorphisms, and in total, 98 different alleles were observed over all loci. Differences in genetic variability of the $F_1$ offspring compared to their wild-caught parents (brood stock) were observed in terms of allele frequency, gene diversity, and heterozygosity. Although the $F_1$ generation of rock bream was missing 16% of the micro satellite alleles, no significant reduction was found in mean heterozygosity of the $F_1$ population compared to the brood stock. Eight of nine loci showed significant Hardy-Weinberg equilibrium (HWE) deviations in the $F_1$ population, while the brood stock deviated from HWE at three micro satellite loci (KOF85, KOF360 and KOF374). These deviations showed mostly a deficit of heterozygotes. Our results provide evidence for genetic differences in the $F_1$ hatchery offspring compared to their wild-caught parents and reinforce the need for a series of consecutive egg collections to avoid the loss of genetic variability. This also further underscores the importance of monitoring genetic variability of hatchery populations for the conservation of natural rock bream resources.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1109-1115
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• 2011

A highly sensitive and specific TaqMan real-time PCR was used to quantify hepatopancreatic parvovirus (HPV) type III infections in wild broodstocks and hatchery-reared postlarvae (PL) of Fenneropenaeus chinensis. Totals of 159 and 162 wild brooders from three locations were captured, and 140 and 180 PL were obtained from seven and six commercial hatcheries in 2007 and 2008, respectively. Among the three wild broodstock groups from 2007, only 1 group showed HPV infection and 3.2% of 159 brooders were positive for HPV infection. In 2008, HPV infections were observed from all three wild broodstock groups with $1.93{\times}10^4$ copies/mg tissue of pleopods. Of 162 brooders, 26.6% were positive for HPV infection. No PL from the two hatcheries collected in 2007 showed HPV infection, and PL from the rest of the five hatcheries had up to $1.74{\times}10^6$ copies/ng of DNA, and PL from three hatcheries showed HPV infections with over 1,000 copies/ng of DNA. The PL from all seven hatcheries collected in 2008 showed up to $2.10{\times}10^5$ HPV copies/ng of DNA. PL from two hatcheries showed less than 100 copies/ng of DNA, but PL from the rest of the hatcheries showed HPV infections with over 1,000 copies/ng of DNA. These results show that HPV type III is widely distributed in Korea in addition to previously reported HPV type I, and they can be effectively detected by type-specific realtime PCR.

• The Korean Journal of Malacology
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• v.29 no.3
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• pp.197-205
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• 2013

Even though seedling production of Haliotis discus hannai has fully developed, the culture of benthic diatom as a live food for larvae is still a barrier to solve in commercial hatchery. The farmer depends on mixed microalgae which are non-selectively attached on the plate by flowing of natural seawater. The adequate diatom on the plate for the larvae in terms of quality and quantity is always significant bottleneck in the hatchery. In this study, two benthic diatom species, Caloneis schroederi and Rhaphoneis sp. were separately cultured in mass and inoculated to four tons' settlement tank of the larvae. And the larvae and the spats were cultured for nineteen and nine weeks, respectively. The result on seedling production of H. discus hannai with this method was compared to that of the farmer's traditional method as a control. With regard to variation of species composition of benthic diatom on the plate, C. schroederi and Rhaphoneis sp. were dominant for first three weeks after inoculation. But the diverse diatoms mainly, Navicula, Amphora, Cylindrotheca, Licmophora, Pleurosigma began to attache on the plate from the 4th week. The larvae attached 2.5 times more in C. schroederi tank than in the control tank. The final total biomass of the seeds in Rhaphoneis sp. tank was 3.2 times more than that of the control tank. The retared-spats in the seedling production also showed significantly higher growth and survival in the spat fed Rhaphoneis sp. or C. schroederi than those in the control group. We suggest that C. schroederi is proper for settlement of the larvae and Rhaphoneis sp. is appropriate for the growth of the larvae and spats in the commercial hatchery of H. discus hannai.

• Korean Journal of Agricultural Science
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• v.46 no.2
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• pp.361-368
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• 2019

The objective of the current study was to determine calcium (Ca) and phosphorus (P) utilization in 4 different hatchery by-products (HBPs) for broiler chickens. The four different HBPs included infertile eggs (IFE), unhatched eggs (UHE), low grade and dead chicks (LDC), and a mixture (MIX) of 55% IFE, 10% UHE, and 10% LDC with 25% hatched eggshells. A total of sixty four 50-day-old Ross 308 broiler chickens were randomly allotted to 1 of 4 dietary treatments with 8 replicates per treatment. Two birds were placed together in one metabolic cage. Additional 16 birds were used to measure the endogenous losses of Ca and P. A forcefeeding procedure (i.e., crop intubation) was used to measure the apparent and true total tract retention (ATTR and TTTR, respectively) of Ca and P in the 4 HBPs. The results showed that the TTTR of Ca in the UHE was less (p < 0.05) than that in the IFE, LDC, and MIX. The amounts of available Ca in the MIX were greater (p < 0.05) than those in the IFE and UHE, which were greater (p < 0.05) than those in the LDC. The TTTR of P was not different among the 4 HBPs. However, the amounts of available P in the LDC were greater (p < 0.05) than those in the IFE and UHE, which were greater (p < 0.05) than those in the MIX. In conclusion, HBPs contain high amounts of available Ca and P because of high concentrations of total Ca and P with a high utilization rate. Therefore, the use of HBPs in broiler diets can reduce costs on Ca and P supplements.

• Animal Bioscience
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• v.34 no.7
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• pp.1181-1192
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• 2021

Objective: The objective of the current study was to investigate the effects of dietary hatchery by-products (HBPs) as a replacement of fish meal (FM) on growth performance, relative organ weight, plasma measurements, immune organ index, meat quality, and tibia characteristics of broiler chickens. Methods: A total of 720 broiler chickens (3 d of age) were randomly allotted to 1 of 9 treatments with 8 replicates. Each replicate consisted of 5 male and 5 female birds. The basal diet was formulated to contain 5.0% commercial FM, whereas eight treatment diets were prepared by replacing 25%, 50%, 75%, or 100% of FM in the basal diet with infertile eggs (IFE) or a mixture of various HBPs (MIX); therefore, the inclusion levels of IFE or MIX in the experimental diets were 1.25%, 2.50%, 3.75%, or 5.00%. The diets and water were provided on an ad libitum basis for 32 d. Results: Increasing inclusion levels of IFE as a replacement of FM in diets had no effects on growth performance, plasma measurements, immune organ index, and tibia characteristics of broiler chickens. Increasing inclusion levels of IFE in diets increased (linear, p<0.05) meat lightness (L^*) but decreased (linear, p<0.05) meat redness (a^*). The breast meat pH at 1-h postmortem was increased (linear, p<0.05) by increasing inclusion levels of IFE in diets. Likewise, increasing inclusion levels of MIX in diets had no effects on growth performance, relative organ weight, plasma measurements, immune organ index, and tibia characteristics. However, increasing inclusion levels of MIX in diets increased (linear, p<0.05) 1-h postmortem pH but decreased (linear, p<0.05) 24-h postmortem pH of breast meat. Increasing inclusion levels of MIX in diets decreased (linear, p<0.05) thiobarbituric acid reactive substances values of breast meat. Conclusion: Both IFE and MIX are suitable alternatives to FM as protein ingredients in broiler diets.

• Korean Journal of Poultry Science
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• v.24 no.4
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• pp.193-198
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• 1997

This study was conducted to obtain the basic information for hatchery by-products as feed resources. Four kinds of by-products from a commercial hatchery, i. e., autoclaved day-old broiler or egg type chicks, dead embryos ＆ infertile eggs of both chicks were used for chemical composition and bioavailability test. Chemical compositions were obtained by AOAC (1990) method, and amino acid and energy bioavailabilities were determined by the method of Sibbald (1976). The crude protein contents of day-old chicks (60.27∼62.59) were higher than those of dead embryos ＆ infertile eggs (39.24∼40.09) , whereas the crude fat contents of all by-products were not different. The crude ash contents were higher in dead embryos ＆ infertile eggs (29.18∼34.49％) than in day-old chicks (6.50∼6.71％). The Ca contents of dead embryos ＆ infertile eggs (8.79∼10.82％) were higher than those of day-old chicks (1.29∼l.30％). The total amino acid contents, overall amino acid availabilities and ME contents were higher in day-old chicks than in dead embryos ＆ infertile eggs. It seems that the day-old chicks of egg strain can be used as a high protein - high energy feed resources and the dead embryos ＆ infertile eggs of broiler or egg type as a high protein-high calcium feed ingredients.