• Applied Microscopy
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• v.42 no.1
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• pp.17-26
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• 2012

Histologic and microstructural changes during the postembryonic development of the wolf spider Arctosa kwangreungensis were studied using light and scanning electron microscopy to examine the relationship between a morphological differentiation and behavioral properties. The postembryo with abdominal yolk sac was stayed inactive in the egg case because its muscular and visual systems were not fully developed to a functional level. The first instar spiderlings, developed from the postembryo by a first molting process, started to exhibit its pigmentation on their body cuticles. In particular, undifferentiated cell clusters of central nervous system (CNS) were densely distributed within the cephalothorax, and highly differentiated abdominal ganglion was observed. They had a characteristic visual system looks more like its adult counterpart, and had segmented appendages looks more like the tiny spiders containing well oriented muscular system. After 3rd instar, spiderlings grew more rapidly with accordance to their consistent growth and periodical molting processes. Thus, the relative area of CNS with respect to cephalothorax was gradually decreased, instead a pair of venom glands, musculature, and connectives occupied the residual area. It has been revealed that the early development of spider can be controled by the feeding condition of larval period, since histologic and microstructural differentiations in both appendages and optic system were completed at the second instar. In particular, behavioral properties of the wandering spiders that depend on vision and their running ability were deeply related to physiological differentiation of the microstructural development.

• Journal of Life Science
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• v.11 no.5
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• pp.447-456
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• 2001

We have recently demonstrated that the fluoroquinolone antibacterial DW-116 caused a significant developmental toxicity in rats. The present study was conducted to determine whether the development toxicity induced by DW-116 treatment was the result of malnutrition fro reduced food intake or the direct effects of test chemical on conceptuses. The test chemical was administered by gavage to pregnant rats from gestational days 6 through 16 at dose levels of 0 and 500 mg/kg/day. A pair-feeding study was also performed in which the pregnant rats received the same amount of diet consumed by the DW-116-treated pregnant rats. All dams were subjected to caesarean section on day 20 of gestation and their fetuses were examined for examined for external, visceral, and skeletal abnormalities. In this treatment group, the maternal toxicities included increased abnormal clinical signs, decreased maternal body weight, suppressed body weight gain during treatment and posttreatment periods, and reduced food intake. The significant developmental toxicities included increased fetal deaths, decreased live fetuses, reduced fetal body weight and placental weight, increased incidence of fetal abnormalities, and increased fetal ossification delay. In this pair-fed group, however, slight maternal toxicities including decreased body weight and suppressed body weight gain during treatment period were observed in comparison with the control group, and minimal development toxicities including reduced fetal and placental weights and increased fetal ossification delay were found. The number of fetal deaths and live fetuses, and the incidences of malformed fetuses and litters with affected fetuses were comparable to the control values. Based on the results, it could be concluded that the development toxicity observed in the treatment group is attributable to the direct effects of Dw-116 treatment, but not to the maternal malnutrition from reduced food consumption during pregnancy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.55-60
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• 1971

There are a lot of kinds of shrimps for fishing baits, but Palaemon modestus is dominant species in the Karak River. The ecology in the natural environments was reported by the author (1970) and this work is an elemental task for the larval stage in shrimp farms. Shrimps were collected from the Karak River and carried to the laboratory. Hatched larvae were reared from June 6 to June 24, 1970 for pre-experiment, and main experiment was provided from August 10 to August 24, 1970. The following is a summary of the results: 1. Hatching period in the laboratory water tank was eight hours ($20^{\circ}C\~20.9^{\circ}C$). 2. The larvae died off from the sixth day after hatch without food. 3. Feeding begins on the third day after hatch. 4. The relationship between the density of food and the consumption was not concerned when the number of Artemia nauplii was 2 to 6 per ml of water. 5. The relationship between the day (X) and the food (Y) is: $$Y=6.49824X^{1.8384}$$ 6. The carapace growth curve is: $Y=1.1608X^{0.10024}$ 7. The relationship between the food (X) and the body length (Y) is: $$Y=2.8114X^{0.12767}$$ 8. The relationship between the carapace length and the body length(Y) is : Y= 3.7564X-0.4601

• Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.10.1-10.8
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• 2018

Substitution effect of white radish' by-product (WRB) and tunic of sea squirt (TSS) for Undaria in feed on growth and carcass composition of abalone was determined. Eight-hundred forty juveniles were distributed into 12 containers. Three formulated diets were prepared in triplicate. A 15% Undaria was included in the control diet. The 15% Undaria was substituted with a same amount of WRB and TSS, referred to as the DRG and TSS diets, respectively. Finally, dry Undaria was also prepared to compare effect of the formulated diets on performance of abalone. The experimental diets were fed to abalone once a day at a satiation level with a little leftover. The feeding trial lasted for 16 weeks. Crude protein, crude lipid, and ash content of the experimental diets changed over all period of time. Higher crude protein and lipid and ash contents retained in all formulated diets compared to the Undaria were observed at 24 and 48 h after seawater immersion. Survival of abalone was not affected by the experimental diets. Weight gain and specific growth rate (SGR) of abalone fed the TSS diet was greater than all other diets. Weight gain and SGR of abalone fed the control diet was not different from those of abalone fed the WRB diet. Proximates of the soft body of abalone was affected by the diets. In conclusion, WRB and TSS are the promising feed ingredients to replace Undaria in abalone feed; especially, TSS is superior to either Undaria or WRB. The formulated diets produced improved growth performance of abalone over the single Undaria.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1284-1291
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• 2020

Objective: To evaluate the effects of the carmine cochineal-resistant spineless cactus genotypes cv. Orelha de Elefante Mexicana (Opuntia) and Miúda (Nopalea) on the intake and digestibility of nutrients, ingestive behavior, performance, and ultrasound measurements of growing lambs. Methods: Thirty-six male (non-castrated) Santa Inês lambs were used, with an average age of 6 months and an initial average weight of 22.0±2.9 kg. They were distributed in a completely randomized design with 3 treatments (Tifton hay, Nopalea and Opuntia) and 12 replications, using initial weight as a covariate. The experimental period was 86 days, with the first 30 days used for the adaptation of the animals to the facilities, diets and management, and the remaining 56 days used for evaluation and data collection. Results: The intake and apparent digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), total carbohydrates (TC), non-fibrous carbohydrates (NFC), and total digestible nutrients (TDN) showed a significant difference (p<0.05) as a function of the diets, with the Nopalea treatment (p<0.05) increasing DM intake (g/kg and % body weight [BW]), CP, TDN, and TC digestibility, whereas the Tifton hay diet led to a high (p<0.001) neutral detergent fiber corrected for ash and protein (NDFap) g/d intake, NDFap (BW %) and digestibility of said nutrient. There was no effect of treatments (p>0.05) on feeding time, however, rumination time and total chewing time were higher (p<0.05) for animals fed Tifton hay. The performance of the animals was similar (p>0.05). For the ultrasound measurements, Nopalea promoted an increase in the final loin eye area, compared to Tifton hay. Conclusion: The use of spineless cactus variety Miúda leads to the greater intake and digestibility of nutrients. The evaluated carmine cochineal-resistant spineless cactus genotypes are alternatives for semi-arid regions as they do not negatively affect the performance of growing lambs.

• Journal of Veterinary Clinics
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• v.27 no.1
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• pp.17-22
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• 2010

The natural herbal antimicrobial additive, Flavo-$SK^{TM}$, was developed by Zoonosis Research Center of Wonkwang University. The purpose of this study was to evaluate the effects of Flavo-$SK^{TM}$ on the health status and performance of growing chickens. This study was conducted on the growing chickens (n=20,000) for 31 days in a growing chickens husbandry. The animals were divided with two groups; Flavo-$SK^{TM}$ treated group (n=10,000) and commercial diet feeding group (n=10,000). The Flavo-$SK^{TM}$ treated animals had provided with commercial diet adding the Flavo-$SK^{TM}$ as 0.29%. During the study period, we compared clinical signs, weight increase rate, diet consumption amount, gross finding, necropsy findings and histopathological findings between the treated group and non treated group. As the results of this clinical trial, the natural herbal antimicrobial additive, Flavo-$SK^{TM}$, showed the effects on disease reduction. It is suggested that Flavo-$SK^{TM}$ has the antimicrobial effects.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.308-314
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• 2010

This study was conducted to investigate the characteristics and concentrations of ammonia produced from the livestock swine nightsoil treated with or without the livestock - environment improving agents. Odor generating device made of acryl was made by volume of 96 L to sample the ammonia odor. When swine night soil was placed in the device, concentration of ammonia averaged out at about 23.4 ppmv and ranged from 16 ppmv to 40 ppmv. Removal efficiencies of them showed 50% to 90% as compared to initial level before spraying, when the spray type agents were used immediately after they purchased. The persistence of the efficiency was retained for first two days. Among the agents, the natural deodorant showed the best efficiency of 87 to 99%. To evaluate the effects of 5 kinds of dietary probiotic powders, the experiments were conducted and based dietary treatments without antibiotics on growing piglets. In experiments, 60 piglets ($6.3{\pm}0.2\;kg$) were subjected to a 35-day feeding trial in which the effects of the dietary probiotic powder on the ammonia emission were compared. The ammonia gas emission was measured for every week. Ammonia emission from the swine nightsoil obtained from piglets supplemented with the probiotics power was lower than that of the nightsoil obtained from pigs in the control treatment (without probiotics). In ammonia removal efficiencies of the experimental groups, some products showed from 71% to 99% removal efficiencies throughout the entire period as compared to the control group. On the other hand, initial reduction of ammonia in some product was effective temporarily. After then, it did not show any reduction efficiency of ammonia.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.1-6
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• 1970

A series of experiments have been made on the mass culture of Phaeodactylum tricornutum, Platymonas sp. and Chlorella sp. in the laboratory. The shortest lag phase was found In the culture of Ph. tricornutum followed by Platymonas sp. and Chlorella sp. As compared to the aeration culture, the stagnant culture, in general, showed long duration of the lag phase, short period of the exponential phase and extremely small daily increment. The relative growth constants of Ph. tricornutum, Chlorella sp. and Platymonas sp. were $0.302{\pm}0.028$, $0.226{\pm}0.013$, and $0.151{\pm}0.008$, respectively The maximum daily increment of the three species and then daily ages are as follows: Ph. tricornutum Maximum daily increment : 47.5, Daily age : 10, Platymonas sp. Maximum daily increment : 5.6, Daily age : 14, Chlorella sp. Maximum daily increment : 21.1, Daily age : 14 Comparing the packed cell volume with a certain number of cells, the largest value was found in the population of Ph. tricornutum followed by Platymenas sp. and Chlorella sp. A straight line relationship exists between the two values, and the magnitude of the relationship coincides well with the size of the cells. The culture of Ph. tricornutum was proved satisfactory for feeding the larvae of bivalves at about 12 days after innoculation and both of Platymenas sp. and Chlorella sp. were about 16 days respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.753-758
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• 2011

The seawater adaptability of land-locked masu salmon Oncorhynchus masou masou via acclimation was examined for aquaculture purposes. The survival, blood chemistry, and histological changes of masu salmon (150 g) were measured after 7-, 15-, and 30-day acclimation periods. After a total of 60 days in seawater cultures that incorporated the various acclimation periods, survival was 83.5, 87.2, and 91.0% for the 7-, 15-, and 30-day periods, respectively; thus, survival increased with longer periods of acclimation. Feeding efficiencies were 32.1, 52.0, and 40.6% for the 7-, 15-, and 30-day periods, and specific growth rates were 0.14, 0.26, and 0.23%, respectively. Generally, masu salmon appeared to exhibit better growth performance after an acclimation period of 15 days. Cortisol concentrations [mean ${\pm}$ SD] for 7, 15, and 30 days of acclimation were $21.0{\pm}6.5$, $17.8{\pm}4.8$, and $21.2{\pm}5.4\;{\mu}g/dl$, with the lowest values occurring with 15 days of acclimation. Osmolarities were $359.2{\pm}26.1$, $350.4{\pm}29.2$, and $354.6{\pm}29.3$ mOsm/kg, and glucose concentrations were $60.7{\pm}20.7$, $72.9{\pm}17.3$, and $76.6{\pm}14.1$ mg/dl for the 7-, 15-, and 30-day acclimation periods, respectively (P < 0.05). The histological study revealed that both gills and both kidneys of the masu salmon exhibited middle- to end-stage and middle-stage lesions in the 7- and 15-day groups, respectively, whereas these organs only had early-stage lesions in the 30-day group in the final experiment. Therefore, the seawater acclimation of masu salmon should involve more than 30 days in seawater.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.212-218
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• 1983

The effect of dietary calcium and magnesium on the 3-Hydroxy-3-methyl-glutaryl coenzyme A reductase (E.C. 1.1.1.34) in rabbit's liver microsomal protein was studied for a period of 4 weeks using isocalories and isonitro-genous as a basal diet. The experimental rabbits fed the following basal diets, such as crude protein 68.45%, carbohydrates 13.38%, fats 16.17% and added some sorts of calcium and magnesium, according to experimental plan making. The subject rabbits were divided into 9 feeding groups. The results are summarized as follows. Body weight gains per week of the groups fed magnesium and basal diet showed a little bit increase, but the groups fed calcium and basal diet showed a little bit decrease compare with control group. In case of serum magnesium, control group was 9.5mg% groups fed basal diet and magnesium were 8.27mg% in average, groups fed basal diet and calcium were 4.45mg% in average. In case of serum calcium, control group was 15.3mg%, groups fed basal diet and magnesium were 14.6mg% in average, groups fed basal diet and calcium were 14.1mg% in average. There was no great difference between magnesium fed groups in serum calcium. In serum triglyceride, control group was 82.8mg%, groups fed magnesium and basal diet were 60.3mg% in average, groups fed calcium and basal diet were 69.5mg% in average. The calcium fed groups were higher than the magnesium fed groups in serum triglyceride. In serum cholesterol, control group was 80mg%, groups fed magnesium and basal diet were 64.3mg% in average, groups fed calcium and basal diet were 56.3mg% in average. The calcium fed groups were lower than the magnesium fed groups in serum cholesterol. In case of the 3-Hydroxy-3-methylglutaryl coenzyme A reductase activity, control group was 0.998nmol/min/mg protein, groups fed magnesium and basal diet of HMG-CoA were 0.849nmol/min/mg in average.