• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.471-477
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• 2008

Development of egg, larvae and juveniles for the Pacific mackerel, Scomber japonicus are described following natural fertilization in the indoor tank of $25^{\circ}C$ water temperature. Following a routine hormone treatment technique for the brood stock, male and female mackerels were artificially matured by intramuscular injections of LHRHa at a dosage of $400{\mu}g/kg$ body weight (BW)+Domperidone at a dosage of $4{\mu}g/kg$ body weight (BW) to induce maturation in a separate aquarium and induced natural spawning. Fertilized eggs were ca. 1.0 mm in diameter; spherical in shape with a single oil globule; pelagic and non-adhesive. Hatching occurs 41 hours after fertilization at $23-24^{\circ}C$. The newly hatched larvae was 3.03 mm in average total length (ATL), the mouth and anus were not open, oil globule located in posterior end of yolk sac, and preanal length was 42.8% of TL. The larvae measuring 2.89 mm ATL, almost absorbed yolk sac and oil globule material in 2 days after hatching, in which the mouth and anus were open. Melanophores, branch or star in shape were observed on the top of head, peritoneal region and along the ventral contour. In 13 days after hatching, the larvae was 6.88 mm ATL, its posterior end of notochord began to flex upward, finfold of caudal fin appeared, jaw teeth were already formed. In 19 days after hatching, the larvae was 7.71 mm ATL completed only caudal fin rays (9+8), and preanal length was 49.4% of TL. In 37 days after hatching, the larvae was 27.4 mm ATL already completed all the fins, and preanal length was 59.9% of TL.

• Journal of Aquaculture
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• v.17 no.1
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• pp.30-38
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• 2004

To estimate the spawning period the annual change of gonadosomatic index (GSI) were examined from January 2000 to December 2001. Fecundity, spawning frequency and egg diameter were measured by ocular observation. Germ cell differentiation during gametogenesis, the reproductive cycle and the first sexual maturity of greenling Hexagrammos otakii were observed under light microscopy from January to December, 2000. GSI began to increase in August and reached the maximum in November when ovary was getting mature. The reproductive cycle of H. otakii can be divided into five successive stages in females: early growing stage (July), late growing stage (July to August), mature stage (September to October), ripe and spent stage (September to December), and recovery and resting stage (December to June). Males showed four successive stages : growing (June to August), mature (August to October), ripe and spent (September to December), and recovery and resting stage (December to May). According to the frequency distributions of egg diameter in spawning season, H. otakii could be one of polycyclic species spawning 2 times or more during one spawning season. Number of total eggs and mature eggs in the absolute fecundity were related to the standard length and body weight, respectively. Number of total eggs and mature eggs in relative fecundity were also proportional to the standard length, but rather these numbers decreased with body weight. Percentages of first sexual maturity of females and males in greenling were over 50% from 19.1 to 21.1cm in length, and 100% for fish over 25.1cm in length. Therefore, both sexes are ready to reproduce after one year old.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1553-1561
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• 2004

Two feeding trials were conducted with 128 pullets from 4 to 20 weeks of age and 96 laying hens from 23 to 63 weeks of age to evaluate the effects of scavenging and type of protein supplement on the feed intake and performance of improved pullets and laying hens. The experiments had a completely randomized design with four dietary treatments and four replicates. Treatments were: Control (Cont), scavenging but with access to a balanced concentrate at night; confinement (CF) and given the control feed ad libitum; scavenging and supplemented at night with the control feed, but with soybean meal replaced by cassava leaf meal (CLM); scavenging and supplemented at night with the control feed, but with fishmeal replaced y soybean meal (SBM). The mean daily dry matter (DMI), metabolizable energy (MEI) and crude protein intakes (CPI) of the pullets and laying hens, respectively, were 28%, and 18% higher for the confinement treatment (CF) compared to the scavenging treatments (p<0.001). The DMI, MEI and CPI of the pullets were not significantly different among scavenging treatments (p>0.05), but for the layers DMI, MEI and CPI were significantly higher for the CLM and SBM treatments compared to the Cont treatment (p<0.001). In the growing period, the average daily weight gain (ADG), supplement feed conversion ratio (FCR) and supplement feed cost/kg eggs (FCS) were not significantly different for CF compared to Cont, and among scavenging treatments (p>0.05). In the laying period, the hen-day production was significantly lower, and supplement FCR and FCS significantly higher for the CF compared to the scavenging treatments (p<0.001). Egg weight, and yolk, albumen and shell percentage and shape index were not significantly different among the scavenging treatments (p>0.05). However, shell and yolk percentages were significantly lower for the CF compared to the Cont treatment (p<0.01). Mortality was significantly higher for the CF compared to the scavenging treatments for pullets, and was significantly lower for the CF compared to scavenging treatments for laying hens (p<0.001). It was concluded that scavenging pullets and layers were getting around 28% and 18%, respectively, of their nutrient requirements from scavenging activities, resulting in correspondingly lower supplement feed conversion ratios and feed costs. Daily gains of the pullets were not affected by scavenging or protein supplement, but egg production and mortality were lower for the confined hens.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.11-14
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• 1975

This work was carried out to determine that ginseng cake (meal) could be substituted for 10% level of chicken feed. The feeding experiment was held with 180 laying hens for 8 weeks. And the results were as tin the followings, 1. Protein content of the ginseng cake was lower (4.25%) than that of the control feed (18.72%: commertial chicken feed), and crude fiber of the ginseng cake was higher (14.73%) than that of the control (9.39%). 2. Slight increasings of body weight were observed in the group of the control feed (10 g) and the group of the feed containing 10% of the ginseng meal (24 g), significant increasing (50 g) was seen in the group of the feed containing 5% of the ginseng meal (p<0.05). 3. The feed efficiency of the ginseng group was slightly higher than that of the control group, but significant defferences were not recognized. 4. Egg laying ratio of the 5% ginseng group was somewhat higher than that of the other groups, and egg weight of each group was almost same. With all the results of this experiments, it was identified that ginseng cake is able to be substituted for the feed of laying hen within 10% level.

• Journal of Korean Society of Forest Science
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• v.96 no.4
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• pp.414-418
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• 2007

The average number of oviposion scars in lower (facing the Land) and upper part (facing the Sun) of P. koraiensis logs were $16.3{\pm}13.9$ and $3.3{\pm}3.6$, respectively. Oviposition preference of Monochamus saltuarius adults was lower part of Pinus koraiensis. Estimated average number of larvae and egg from oviposition scars ($64.7{\pm}23.8$) in P. koraiensis logs was $18.8{\pm}10.0$ in the laboratory condition. However, oviposition scars were $63.6{\pm}31.1$ and average number of larvae and egg was $2.0{\pm}2.6$ in field condition. When we fed with inner bark (phloem) and xylem of P. koraiensis, body weight of M. saltuarius larvae was normal. However, when we only fed xylem of P. koraiensis, body weight and size were reduced but they were recovered after feeding inner bark (phloem). Esterase isozymes were assessed from larvae fat body of M. saltuarius and Est1 were specifically activated when we fed with inner bark (phloem) and xylem.

• Korean Journal of Ichthyology
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• v.28 no.4
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• pp.260-266
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• 2016

We determined the morphologic characteristics (body weight and abdomen inflation degree) of the mother fish of sevenband grouper, Epinephelus septemfasciatus producing the healthy eggs. Experimental fish were chosen from the reared fish in the sea cage for 6 years. The fish were divided into four size groups by body weight: 4.0~5.0, 5.0~6.0, and 6.0~7.0 kg and four stages (I~IV) by the abdomen inflation degree. After hormone treatment, we observed the ovulation amount of induced eggs, rate of buoyant, fertilization, embryonic survival, and hatching. Egg and oil globule diameter was measured. In order to observe gonadal development, we calculated gonadosomatic index (GSI) and conducted its historical analysis. The ovulation occurred from all experimental fishes over 5.0 kg. The rate of buoyant, fertilization, and embryonic survival was the highest in 6.0~7.0 kg. Hatching rate was the highest in 5.0~6.0 kg. Stage I and II did not induce ovulation. GSI was $0.31{\pm}0.10%$ in stage I, $0.74{\pm}0.25%$ in stage II, $4.68{\pm}0.40%$ in stage III and $6.86{\pm}0.12%$ in stage IV. The rate of buoyant, fertilization, embryonic survival and hatching was the highest in stage III.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.219-224
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• 2019

The super mealworm, Zophobas morio, is mainly used as food for pets, fish, reptiles, amphibians, birds, and as snacks. An experiment was conducted to investigate the effects of temperature, supplementary feeding, and spawning interval on super mealworm rearing. To efficiently rear this species, the insects were bred at a temperature of $27^{\circ}C$ or higher and reached a weight of over 0.6 g at 80 days after hatching. Supplementary feed (with high protein content: 10% of soybean meal and 10% of fish meal) enabled larvae to reach a weight of over 0.7 g at 80 days after hatching. Mass rearing of super mealworm requires increase in egg production (i.e., high yield) and uniformity of larvae. Adults were transferred to spawning bases every 5, 10, or 15 days (three treatments), which resulted in a total of 7,256, 5,439, 2,060 hatched larvae, respectively. It is possible to obtain more than 7,000 larvae by transferring the egg-laying frame to the spawning base at intervals of 5 days and with nine spawning operations; this procedure generates larvae weighing over 0.68 g each.

• Korean Journal of Poultry Science
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• v.43 no.1
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• pp.15-20
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• 2016

This research was carried out to determine the effect of Cudrania tricuspidata fruit (CTF) on the performance of laying hens, egg quality, yolk fatty acid composition, Immunoglobulin G (IgG) and blood composition. A total 288 Brown Nick laying hens of 48 weeks old replaced into 4 groups with 4 replicates of 18 birds in each. Treatments were added with 0, 0.25, 0.5, 1.0% CTF containing dried seed and pulp. Metabolizable energy (ME) and crude protein (CP) were 2,800 kcal/kg and 16.0% in basal diets, respectively. Egg production and daily eggmass were significantly increased in 1.0% CTF addition treatment compared to those of other treatments (P<0.05). Egg weight and feed intake were not different among treatments. Feed conversion ratio showed the lower result in 1.0% CTF treatment than other treatments (P<0.05). Eggshell color was not influenced by the addition of CTF. Albumin height, Haugh unit and eggshell breaking strength was not statistically different, but seemed to be higher as dietary CTF addition increased. Yolk color was increased as dietary CTF increased and was the highest in 1.0% CTF group (P<0.05). Fatty acids were not shown the consistency in yolk. Blood cholesterol and triglyceride (TG) of birds fed CTF were significantly low compared to those of control. IgG was also statistically higher in CTF treatments than control (P<0.05). As the results of this experiment, the addition of 1% CTF would be the most effective on performance and egg quality, whereas the 0.25% CTF addition in basal diets seemed to be optimum to improve the blood cholesterol, TG,high density lipoprotein cholesterol (HDL-CHOL), IgG in laying hens.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.540-545
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• 1982

An energy metabolism study was conducted with two commercial strains of meat-type chickens, Hubbard and Cobb, and two egg strains, Hy Line and Korean-bred Hanhyup 325. The heat production of growing chickens from each strain were measured by the use of an open-circuit gravimetric respiration calorimeter. The data obtained from this study were summarized as fallows. 1. The average body weight of 9-wk-old Hubbard broilers reared in battery cages was 2,570g/bird. The average body weights of 9-wk-old Hy Line chicks and Hanhyup 325 were 777 and 748g/bird, respectively. 2. At 3 weeks of age, the Hubbard broiler chicks consumed two times the feed consumed by Hy Line chicks (54.6g VS. 26.7g/bird/day). These values increased to 151g and 57.2g/bird/day, respectively, at 8 weeks of age, indicating that the difference in feed intake between meat and egg-type chicks tends to increase as they grow older. In terms of water consumption, the 5-wk-old Hubbard broiler chicks drank $226m{\ell}/bird/day$ as compared with $58m{\ell}$ by Hy Line chicks. These values increased to 282 and $70m{\ell}$, respectively, at 8 weeks of age. 3. The excreta outputs of Hubbard broilers and Hy Line chicks were 18.7 and 6.1g DM/bird/day at 4 weeks of age, and 41.5 and 10.0g DM/bird/day at 8 weeks of age, respectively. 4. The energy metabolizability of broiler chicks were 75.4~77.1% compared to 75.0~83.5% by egg-type chicks. 5. The respiratory quotient (RQ) was between 0.78 and 0.97. There seems to be no difference in RQ between meat and egg-type chicks. The RQ tended to decrease when feed intake was low and vice versa. 6. Both meat and egg-type chicks produced $83.1{\sim}123.1Kcal/kg^{\frac{3}{4}}B.W./day$. The considerably low value of $83Kcal/kg^{\frac{3}{4}}B.W./day$ was obtained when the chicks were off the feed under the stressful conditions. The high value of 123.1Kcal was obtained when the chicken chamber temperature rose to $27{\sim}34^{\circ}C$.

• Korean Journal of Poultry Science
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• v.34 no.1
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• pp.37-42
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• 2007

This study was conducted to investigate the effects of graded levels of a herbal recipe(Herb Mix $Gold^{(R)}$, Herb BIO Co.) supplemented to a commercial layer diet. The Herb Mix $Gold^{(R)}$ is an improved recipe of Herb $Mix^{(R)}$, fortified with Angelica gigas, Discorea japonica and Ligusticum jeholense. A total of 720 layers (Hy-Line Brown) of 45 wks old were assigned to one of six treatments; control, 0.2% Herb $Mix^{(R)}$, 0.1%, 0.2%, and 0.3% Herb Mix $Gold^{(R)}$, and 6 ppm Avilamycin. Each treatment had 6 replicates of 20 birds each housed in 2 birds cages. Birds were fed diets and water ad libitum for 5 weeks. Hen-day egg production was significantly (P<0.05) different among treatments. Herb Mix $Gold^{(R)}$ 0.2% treatment showed the highest egg production followed by Herb Mix $Gold^{(R)}$ 0.3%, Herb $Mix^{(R)}$ 0.2%, Herb Mix $Gold^{(R)}$ 0.1%, Avilamycin 6 ppm and the control. Hen-housed egg production, egg weight, soft and broken egg ration, feed intake, feed conversion ratio, shell strength, shell thickness, shell color index, Haugh unit and yolk color index were not significantly different among treatments. Nor was cfu of Cl. perfringens and E. coli and Lactobacilli in the small intestinal content significantly different among treatments. The number of white and red blood cells, hemoglobin, heterophil, lymphocyte, thus heterophil to lymphocyte ratio were not significantly modified. It was concluded that Herb Mix $Gold^{(R)}$ at the level of 0.2% in the layer diet improves laying performance.